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Sample records for mating sterile male

  1. The Sterile Insect Technique for Controlling Populations of Aedes albopictus (Diptera: Culicidae) on Reunion Island: Mating Vigour of Sterilized Males

    PubMed Central

    Oliva, Clelia F.; Jacquet, Maxime; Gilles, Jeremie; Lemperiere, Guy; Maquart, Pierre-Olivier; Quilici, Serge; Schooneman, François; Vreysen, Marc J. B.; Boyer, Sebastien

    2012-01-01

    Reunion Island suffers from high densities of the chikungunya and dengue vector Aedes albopictus. The sterile insect technique (SIT) offers a promising strategy for mosquito-borne diseases prevention and control. For such a strategy to be effective, sterile males need to be competitive enough to fulfil their intended function by reducing wild mosquito populations in natura. We studied the effect of irradiation on sexual maturation and mating success of males, and compared the sexual competitiveness of sterile versus wild males in the presence of wild females in semi-field conditions. For all untreated or sterile males, sexual maturation was completed within 13 to 20 h post-emergence and some males were able to inseminate females when 15 h old. In the absence of competition, untreated and sterile males were able to inseminate the same number of virgin females during 48 h, in small laboratory cages: an average of 93% of females was inseminated no matter the treatment, the age of males, and the sex ratio. Daily mating success of single sterile males followed the same pattern as for untreated ones, although they inseminated significantly fewer females after the ninth day. The competitiveness index of sterile males in semi-field conditions was only 0.14 when they were released at 1-day old, but improved to 0.53 when the release occurred after a 5-day period in laboratory conditions. In SIT simulation experiments, a 5∶1 sterile to wild male ratio allowed a two-fold reduction of the wild population’s fertility. This suggests that sterile males could be sufficiently competitive to mate with wild females within the framework of an SIT component as part of an AW-IPM programme for suppressing a wild population of Ae. albopictus in Reunion Island. It will be of interest to minimise the pre-release period in controlled conditions to ensure a good competitiveness without increasing mass rearing costs. PMID:23185329

  2. Effects of x-ray irradiation on male navel orangeworm (Lepidoptera: Pyralidae) on mating, fecundity, fertility, and inherited sterility

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Male adult navel orangeworm, Amyelois transitella, were irradiated using a laboratory x-ray emitter to determine the dose needed to achieve complete egg sterility of mated female moths and inherited egg sterility of F1 generation. Adult male A. transitella were irradiated in a series of two experime...

  3. Mass rearing history negatively affects mating success of male Anastrepha ludens (Diptera: Tephritidae) reared for sterile insect technique programs.

    PubMed

    Rull, Juan; Brunel, Odette; Mendez, Maria Elena

    2005-10-01

    Mating competitiveness and sterility induction into cohorts of wild Anastrepha ludens (Loew) (Diptera: Tephritidae) was compared among wild and laboratory flies reared for use in the sterile insect technique Mexican program. Laboratory flies stemming from an 11-yr-old bisexual strain were either not irradiated, irradiated at 3 krad (low dose), or irradiated at 8 krad. In 30 by 30 by 30-cm Plexiglas cages, where a cohort of laboratory flies (male and female) irradiated at different doses (0, 3, and 8 krad) was introduced with a cohort of wild flies, males and females of each type mated randomly among themselves. Compared with nonirradiated laboratory and wild males, irradiated males, irrespective of dose (3 or 8 krad), induced shorter refractory periods and greater mating frequency in wild females. Nevertheless, laboratory flies irradiated at a low dose induced greater sterility into cohorts of wild flies than laboratory flies irradiated at a high dose. In a 3 by 3 by 3-m walk-in cage, wild males gained significantly more matings with wild females than nonirradiated and irradiated laboratory males a finding that revealed a strong effect of strain on mating performance. Mating incompatibility of the laboratory strain might have obscured the effect of reduced irradiation doses on male mating performance in the walk-in cage. Our results highlight an urgent need to replace the A. ludens strain currently used by the Mexican fruit fly eradication campaign and at least suggest that reducing irradiation doses result in an increase in sterility induction in wild populations.

  4. Transient population dynamics of mosquitoes during sterile male releases: modelling mating behaviour and perturbations of life history parameters.

    PubMed

    Stone, Christopher M

    2013-01-01

    The release of genetically-modified or sterile male mosquitoes offers a promising form of mosquito-transmitted pathogen control, but the insights derived from our understanding of male mosquito behaviour have not fully been incorporated into the design of such genetic control or sterile-male release methods. The importance of aspects of male life history and mating behaviour for sterile-male release programmes were investigated by projecting a stage-structured matrix model over time. An elasticity analysis of transient dynamics during sterile-male releases was performed to provide insight on which vector control methods are likely to be most synergistic. The results suggest that high mating competitiveness and mortality costs of released males are required before the sterile-release method becomes ineffective. Additionally, if released males suffer a mortality cost, older males should be released due to their increased mating capacity. If released males are of a homogenous size and size-assortative mating occurs in nature, this can lead to an increase in the abundance of large females and reduce the efficacy of the population-suppression effort. At a high level of size-assortative mating, the disease transmission potential of the vector population increases due to male releases, arguing for the release of a heterogeneously-sized male population. The female population was most sensitive to perturbations of density-dependent components of larval mortality and female survivorship and fecundity. These findings suggest source reduction might be a particularly effective complement to mosquito control based on the sterile insect technique (SIT). In order for SIT to realize its potential as a key component of an integrated vector-management strategy to control mosquito-transmitted pathogens, programme design of sterile-male release programmes must account for the ecology, behaviour and life history of mosquitoes. The model used here takes a step in this direction and can

  5. Wing Morphometry and Acoustic Signals in Sterile and Wild Males: Implications for Mating Success in Ceratitis capitata.

    PubMed

    de Souza, João Maria Gomes Alencar; de Lima-Filho, Paulo Augusto; Molina, Wagner Franco; de Almeida, Lúcia Maria; de Gouveia, Milson Bezerra; de Macêdo, Francisco Pepino; Laumann, Raul Alberto; Paranhos, Beatriz Aguiar Jordão

    2015-01-01

    The sterile insect technique (SIT) is widely utilized in the biological control of fruit flies of the family Tephritidae, particularly against the Mediterranean fruit fly. This study investigated the interaction between mating success and morphometric variation in the wings and the production of acoustic signals among three male groups of Ceratitis capitata (Wiedemann): (1) wild males, (2) irradiated with Co-60 (steriles), and (3) irradiated (steriles) and treated with ginger oil. The canonical variate analysis discriminated two groups (males irradiated and males wild), based on the morphological shape of the wings. Among males that emit buzz signals, wild males obtained copulation more frequently than males in Groups 2 and 3. The individuals of Group 3 achieved more matings than those in Group 2. Wild males displayed lower pulse duration, higher intervals between pulses, and higher dominant frequency. Regarding the reproductive success, the morphological differences in the wings' shape between accepted and nonaccepted males are higher in wild males than in the irradiated ones. The present results can be useful in programs using the sterile insect technique for biological control of C. capitata.

  6. Wing Morphometry and Acoustic Signals in Sterile and Wild Males: Implications for Mating Success in Ceratitis capitata

    PubMed Central

    de Souza, João Maria Gomes Alencar; Molina, Wagner Franco; de Almeida, Lúcia Maria; de Gouveia, Milson Bezerra; de Macêdo, Francisco Pepino; Laumann, Raul Alberto; Paranhos, Beatriz Aguiar Jordão

    2015-01-01

    The sterile insect technique (SIT) is widely utilized in the biological control of fruit flies of the family Tephritidae, particularly against the Mediterranean fruit fly. This study investigated the interaction between mating success and morphometric variation in the wings and the production of acoustic signals among three male groups of Ceratitis capitata (Wiedemann): (1) wild males, (2) irradiated with Co-60 (steriles), and (3) irradiated (steriles) and treated with ginger oil. The canonical variate analysis discriminated two groups (males irradiated and males wild), based on the morphological shape of the wings. Among males that emit buzz signals, wild males obtained copulation more frequently than males in Groups 2 and 3. The individuals of Group 3 achieved more matings than those in Group 2. Wild males displayed lower pulse duration, higher intervals between pulses, and higher dominant frequency. Regarding the reproductive success, the morphological differences in the wings' shape between accepted and nonaccepted males are higher in wild males than in the irradiated ones. The present results can be useful in programs using the sterile insect technique for biological control of C. capitata. PMID:26075293

  7. Precocious sexual signalling and mating in Anastrepha fraterculus (Diptera: Tephritidae) sterile males achieved through juvenile hormone treatment and protein supplements.

    PubMed

    Liendo, M C; Devescovi, F; Bachmann, G E; Utgés, M E; Abraham, S; Vera, M T; Lanzavecchia, S B; Bouvet, J P; Gómez-Cendra, P; Hendrichs, J; Teal, P E A; Cladera, J L; Segura, D F

    2013-02-01

    Sexual maturation of Anastrepha fraterculus is a long process. Methoprene (a mimic of juvenile hormone) considerably reduces the time for sexual maturation in males. However, in other Anastrepha species, this effect depends on protein intake at the adult stage. Here, we evaluated the mating competitiveness of sterile laboratory males and females that were treated with methoprene (either the pupal or adult stage) and were kept under different regimes of adult food, which varied in the protein source and the sugar:protein ratio. Experiments were carried out under semi-natural conditions, where laboratory flies competed over copulations with sexually mature wild flies. Sterile, methoprene-treated males that reached sexual maturity earlier (six days old), displayed the same lekking behaviour, attractiveness to females and mating competitiveness as mature wild males. This effect depended on protein intake. Diets containing sugar and hydrolyzed yeast allowed sterile males to compete with wild males (even at a low concentration of protein), while brewer´s yeast failed to do so even at a higher concentration. Sugar only fed males were unable to achieve significant numbers of copulations. Methoprene did not increase the readiness to mate of six-day-old sterile females. Long pre-copulatory periods create an additional cost to the management of fruit fly pests through the sterile insect technique (SIT). Our findings suggest that methoprene treatment will increase SIT effectiveness against A. fraterculus when coupled with a diet fortified with protein. Additionally, methoprene acts as a physiological sexing method, allowing the release of mature males and immature females and hence increasing SIT efficiency.

  8. Colonization of a hybrid strain to restore male Anastrepha ludens (Diptera: Tephritidae) mating competitiveness for sterile insect technique programs.

    PubMed

    Rull, Juan; Barreda-Landa, Abraham

    2007-06-01

    To restore male mating competitiveness of Mexican fruit flies, Anastrepha ludens (Loew) (Diptera: Tephritidae), reared for sterile insect releases by the Mexican Fruit fly Eradication Campaign, two strain replacement techniques were evaluated. Field cage male competitiveness tests revealed that laboratory males of the Metapa strain mated 3 times less often with wild females than field-collected wild males. A strain developed from the cross of wild males and laboratory females (hybrid strain) was similar to a strain developed from the cross of laboratory males and females (laboratory strain) in that its females produced similar amounts of eggs and the eggs displayed similar levels of hatch and egg-to-pupa transformation in artificial diet. By contrast, a strain developed from the cross of wild males and females (wild strain), forced into artificial rearing, experienced a series of bottlenecks involving reduced egg laying and extremely poor development in diet. The male F1 progeny of the hybrid strain and field-collected wild males outcompeted Fl laboratory males in field cage tests for matings with field-collected wild females. In conclusion, we found that strains developed from the cross of wild males and laboratory females allowed us to restore male mating competitiveness of F1 Mexican fruit flies without compromising mass-rearing production.

  9. Impact of Salivary Gland Hypertrophy Virus Infection on the Mating Success of Male Glossina pallidipes: Consequences for the Sterile Insect Technique

    PubMed Central

    Mutika, Gratian N.; Marin, Carmen; Parker, Andrew G.; Boucias, Drion G.; Vreysen, Marc J. B.; Abd-Alla, Adly M. M.

    2012-01-01

    Many species of tsetse flies are infected by a virus (GpSGHV) that causes salivary gland hypertrophy (SGH). Female Glossina pallidipes (Austen) with SGH symptoms (SGH+) have reduced fecundity and SGH+ male G. pallidipes are unable to inseminate female flies. Consequently, G. pallidipes laboratory colonies with a high prevalence of SGH have been difficult to maintain and have collapsed on several occasions. To assess the potential impact of the release of SGH+ sterile male G. pallidipes on the efficacy of an integrated control programme with a sterile insect technique (SIT) component, we examined the mating efficiency and behaviour of male G. pallidipes in field cages in relation to SGH prevalence. The results showed in a field cage setting a significantly reduced mating frequency of 19% for a male G. pallidipes population with a high prevalence of SGH (83%) compared to 38% for a male population with a low prevalence of SGH (7%). Premating period and mating duration did not vary significantly with SGH status. A high percentage (>80%) of females that had mated with SGH+ males had empty spermathecae. The remating frequency of female G. pallidipes was very low irrespective of the SGH status of the males in the first mating. These results indicate that a high prevalence of SGH+ in G. pallidipes not only affects colony stability and performance but, in view of their reduced mating propensity and competitiveness, releasing SGH+ sterile male G. pallidipes will reduce the efficiency of a sterile male release programme. PMID:22912687

  10. Precocious sexual signalling and mating in Anastrepha fraterculus (Diptera: Tephritidae) sterile males achieved through juvenile hormone treatment and protein supplements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sexual maturation of Anastrepha fraterculus is a long process. Methoprene (a mimic of juvenile hormone) considerably reduces the time for sexual maturation in males. However, in other Anastrepha species, this effect depends on protein intake at the adult stage. Here, we evaluated the mating competit...

  11. Swarming and mating behavior of male Anopheles arabiensis Patton (Diptera: Culicidae) in an area of the Sterile Insect Technique Project in Dongola, northern Sudan.

    PubMed

    Hassan, Mo'awia M; Zain, Hussam M; Basheer, Mohammed A; Elhaj, Hassab-Elrasoul F; El-Sayed, Badria B

    2014-04-01

    The problems facing the conventional mosquito control methods including resistance to insecticides have led to the development of alternative methods such as the Sterile Insect Technique (SIT) to suppress populations of the malaria vector Anopheles arabiensis in northern Sudan. This method entails the release of large numbers of irradiated males to compete against wild conspecifics for mating with virgin females in the field. The swarming and mating behaviors of this species were conducted at two field sites during the period 2009-2012 in Dongola, northern Sudan. Observations were made in the field sites and in a contained semi-field enclosure. In addition, participation of released irradiated-marked males in the swarms of wild mosquito was investigated. Swarms were observed on sunset in the vicinity of larval habitats around irrigation channel and stopped with the onset of the darkness about 21-25 min after the start. Swarms were observed above visual markers such as palm trees, bare ground, and manure. Several couples were observed leaving the swarms in copula in the direction of the sunlight. The majority of copulations were observed within 12-15 min of the start of swarming. Relatively low insemination rates (28%) of females collected from coupling pairs were observed. Irradiated-marked males were observed to join the natural swarms regularly, indicating their probable competitiveness with the other wild males. These findings enhance the feasibility of staging an SIT campaign against malaria vector in Northern State-Sudan.

  12. Puzzles in modern biology. I. Male sterility, failure reveals design.

    PubMed

    Frank, Steven A

    2016-01-01

    Many human males produce dysfunctional sperm. Various plants frequently abort pollen. Hybrid matings often produce sterile males. Widespread male sterility is puzzling. Natural selection prunes reproductive failure. Puzzling failure implies something that we do not understand about how organisms are designed. Solving the puzzle reveals the hidden processes of design.

  13. Puzzles in modern biology. I. Male sterility, failure reveals design

    PubMed Central

    Frank, Steven A.

    2016-01-01

    Many human males produce dysfunctional sperm. Various plants frequently abort pollen. Hybrid matings often produce sterile males. Widespread male sterility is puzzling. Natural selection prunes reproductive failure. Puzzling failure implies something that we do not understand about how organisms are designed. Solving the puzzle reveals the hidden processes of design. PMID:28004842

  14. Combining the Sterile Insect Technique with the Incompatible Insect Technique: III-Robust Mating Competitiveness of Irradiated Triple Wolbachia-Infected Aedes albopictus Males under Semi-Field Conditions

    PubMed Central

    Zhang, Dongjing; Lees, Rosemary Susan; Xi, Zhiyong; Bourtzis, Kostas; Gilles, Jeremie R. L.

    2016-01-01

    Combination of the sterile insect technique with the incompatible insect technique is considered to be a safe approach to control Aedes albopictus populations in the absence of an accurate and scalable sex separation system or genetic sexing strain. Our previous study has shown that the triple Wolbachia-infected Ae. albopictus strain (wAlbA, wAlbB and wPip) was suitable for mass rearing and females could be completely sterilized as pupae with a radiation dose of at least 28 Gy. However, whether this radiation dose can influence the mating competitiveness of the triple infected males was still unknown. In this study we aimed to evaluate the effects of irradiation on the male mating competitiveness of the triple infected strain under laboratory and semi-field conditions. The results herein indicate that irradiation with a lower, female-sterilizing dose has no negative impact on the longevity of triple infected males while a reduced lifespan was observed in the wild type males (wAlbA and wAlbB) irradiated with a higher male-sterilizing dose, in small cages. At different sterile: fertile release ratios in small cages, triple-infected males induced 39.8, 81.6 and 87.8% sterility in a wild type female population at 1:1, 5:1 and 10:1 release ratios, respectively, relative to a fertile control population. Similarly, irradiated triple infected males induced 31.3, 70.5 and 89.3% sterility at 1:1, 5:1 and 10:1 release ratios, respectively, again relative to the fertile control. Under semi-field conditions at a 5:1 release ratio, relative to wild type males, the mean male mating competitiveness index of 28 Gy irradiated triple-infected males was significantly higher than 35 Gy irradiated wild type males, while triple infected males showed no difference in mean mating competitiveness to either irradiated triple-infected or irradiated wild type males. An unexpected difference was also observed in the relative male mating competitiveness of the triple infected strain after

  15. Combining the Sterile Insect Technique with the Incompatible Insect Technique: III-Robust Mating Competitiveness of Irradiated Triple Wolbachia-Infected Aedes albopictus Males under Semi-Field Conditions.

    PubMed

    Zhang, Dongjing; Lees, Rosemary Susan; Xi, Zhiyong; Bourtzis, Kostas; Gilles, Jeremie R L

    2016-01-01

    Combination of the sterile insect technique with the incompatible insect technique is considered to be a safe approach to control Aedes albopictus populations in the absence of an accurate and scalable sex separation system or genetic sexing strain. Our previous study has shown that the triple Wolbachia-infected Ae. albopictus strain (wAlbA, wAlbB and wPip) was suitable for mass rearing and females could be completely sterilized as pupae with a radiation dose of at least 28 Gy. However, whether this radiation dose can influence the mating competitiveness of the triple infected males was still unknown. In this study we aimed to evaluate the effects of irradiation on the male mating competitiveness of the triple infected strain under laboratory and semi-field conditions. The results herein indicate that irradiation with a lower, female-sterilizing dose has no negative impact on the longevity of triple infected males while a reduced lifespan was observed in the wild type males (wAlbA and wAlbB) irradiated with a higher male-sterilizing dose, in small cages. At different sterile: fertile release ratios in small cages, triple-infected males induced 39.8, 81.6 and 87.8% sterility in a wild type female population at 1:1, 5:1 and 10:1 release ratios, respectively, relative to a fertile control population. Similarly, irradiated triple infected males induced 31.3, 70.5 and 89.3% sterility at 1:1, 5:1 and 10:1 release ratios, respectively, again relative to the fertile control. Under semi-field conditions at a 5:1 release ratio, relative to wild type males, the mean male mating competitiveness index of 28 Gy irradiated triple-infected males was significantly higher than 35 Gy irradiated wild type males, while triple infected males showed no difference in mean mating competitiveness to either irradiated triple-infected or irradiated wild type males. An unexpected difference was also observed in the relative male mating competitiveness of the triple infected strain after

  16. Neural Circuits: Male Mating Motifs.

    PubMed

    Benton, Richard

    2015-09-02

    Characterizing microcircuit motifs in intact nervous systems is essential to relate neural computations to behavior. In this issue of Neuron, Clowney et al. (2015) identify recurring, parallel feedforward excitatory and inhibitory pathways in male Drosophila's courtship circuitry, which might explain decisive mate choice.

  17. Bactrocera dorsalis male sterilization by targeted RNA interference of spermatogenesis: empowering sterile insect technique programs

    PubMed Central

    Dong, Yong-Cheng; Wang, Zhi-Jian; Chen, Zhen-Zhong; Clarke, Anthony R.; Niu, Chang-Ying

    2016-01-01

    RNA interference (RNAi) is a genetic technique which has novel application for sustainable pest control. The Sterile Insect Technique (SIT) uses releases of mass-produced, sterile male insects to out-compete wild males for mates to reduce pest populations. RNAi sterilization of SIT males would have several advantages over radiation sterilization, but to achieve this appropriate target genes must first be identified and then targeted with interference technology. With this goal, eight spermatogenesis related candidate genes were cloned and tested for potential activity in Bactrocera dorsalis. The knockdown of candidate genes by oral delivery of dsRNAs did not influence the mating of male flies, but significantly affected the daily average number of eggs laid by females, and reduced egg hatching rate by 16–60%. RNAi negatively affected spermatozoa quantitatively and qualitatively. Following the mating of lola-/topi-/rac-/rho-/upd-/magu-silenced males, we recorded a significant decrease in number and length of spermatozoa in female spermatheca compared to gfp-silenced control group. In a greenhouse trial, the number of damaged oranges and B. dorsalis larvae were significantly reduced in a dsrho-treated group compared with the dsgfp group. This study provides strong evidence for the use RNAi in pest management, especially for the improvement of SIT against B. dorsalis and other species. PMID:27767174

  18. Bactrocera dorsalis male sterilization by targeted RNA interference of spermatogenesis: empowering sterile insect technique programs.

    PubMed

    Dong, Yong-Cheng; Wang, Zhi-Jian; Chen, Zhen-Zhong; Clarke, Anthony R; Niu, Chang-Ying

    2016-10-21

    RNA interference (RNAi) is a genetic technique which has novel application for sustainable pest control. The Sterile Insect Technique (SIT) uses releases of mass-produced, sterile male insects to out-compete wild males for mates to reduce pest populations. RNAi sterilization of SIT males would have several advantages over radiation sterilization, but to achieve this appropriate target genes must first be identified and then targeted with interference technology. With this goal, eight spermatogenesis related candidate genes were cloned and tested for potential activity in Bactrocera dorsalis. The knockdown of candidate genes by oral delivery of dsRNAs did not influence the mating of male flies, but significantly affected the daily average number of eggs laid by females, and reduced egg hatching rate by 16-60%. RNAi negatively affected spermatozoa quantitatively and qualitatively. Following the mating of lola-/topi-/rac-/rho-/upd-/magu-silenced males, we recorded a significant decrease in number and length of spermatozoa in female spermatheca compared to gfp-silenced control group. In a greenhouse trial, the number of damaged oranges and B. dorsalis larvae were significantly reduced in a dsrho-treated group compared with the dsgfp group. This study provides strong evidence for the use RNAi in pest management, especially for the improvement of SIT against B. dorsalis and other species.

  19. Modeling the suppression of sea lamprey populations by the release of sterile males or sterile females

    USGS Publications Warehouse

    Klassen, Waldemar; Adams, Jean V.; Twohey, Michael B.

    2004-01-01

    The suppressive effects of trapping adult sea lampreys, Petromyzon marinus Linnaeus, and releasing sterile males (SMRT) or females (SFRT) into a closed system were expressed in deterministic models. Suppression was modeled as a function of the proportion of the population removed by trapping, the number of sterile animals released, the reproductive rate and sex ratio of the population, and (for the SFRT) the rate of polygyny. Releasing sterile males reduced populations more quickly than did the release of sterile females. For a population in which 30% are trapped, sterile animals are initially released at ratio of 10 sterile to 1 fertile animal, 5 adult progeny are produced per fertile mating, 60% are male, and males mate with an average of 1.65 females, the initial population is reduced 87% by SMRT and 68% by SFRT in one generation. The extent of suppression achieved is most sensitive to changes in the initial sterile release ratio. Given the current status of sea lamprey populations and trapping operations in the Great Lakes, the sterile-male-release technique has the best chance for success on a lake-wide basis if implemented in Lake Michigan. The effectiveness of the sterile-female-release technique should be investigated in a controlled study. Advancing trapping technology should be a high priority in the near term, and artificial rearing of sea lampreys to the adult stage should be a high priority in the long term. The diligent pursuit of sea lamprey suppression over a period of several decades can be expected to yield great benefits.

  20. Male-male interactions and mating kinetics in Drosophila.

    PubMed

    Wallace, B

    1990-05-01

    Male-male interaction (K) has been estimated from data on the attrition rate of virgin females per minute in a study of the mating kinetics in Drosophila. K is expressed as the time males expend on other males relative to that expended while searching for, courting, and copulating with females. The value of K in these studies ranged from 0 (approximately) to .695; it was affected both by strain (sepia or ebony D. melanogaster and wild-type D. simulans) and by size of the mating chamber. Host-parasitoid models of ecologists appear to be appropriate for examining mating kinetics in Drosophila.

  1. Targeting male mosquito mating behaviour for malaria control.

    PubMed

    Diabate, Abdoulaye; Tripet, Frédéric

    2015-06-26

    Malaria vector control relies heavily on the use of Long-Lasting Insecticidal Nets (LLINs) and Indoor Residual Spraying (IRS). These, together with the combined drug administration efforts to control malaria, have reduced the death toll to less than 700,000 deaths/year. This progress has engendered real excitement but the emergence and spread of insecticide resistance is challenging our ability to sustain and consolidate the substantial gains that have been made. Research is required to discover novel vector control tools that can supplement and improve the effectiveness of those currently available. Here, we argue that recent and continuing progress in our understanding of male mating biology is instrumental in the implementation of new approaches based on the release of either conventional sterile or genetically engineered males. Importantly, further knowledge of male biology could also lead to the development of new interventions, such as sound traps and male mass killing in swarms, and contribute to new population sampling tools. We review and discuss recent advances in the behavioural ecology of male mating with an emphasis on the potential applications that can be derived from such knowledge. We also highlight those aspects of male mating ecology that urgently require additional study in the future.

  2. Estimating SIT-driven population reduction in the Mediterranean fruit fly, Ceratitis capitata, from sterile mating.

    PubMed

    Juan-Blasco, M; Sabater-Muñoz, B; Pla, I; Argilés, R; Castañera, P; Jacas, J A; Ibáñez-Gual, M V; Urbaneja, A

    2014-04-01

    Area-wide sterile insect technique (SIT) programs assume that offspring reduction of the target population correlates with the mating success of the sterile males released. However, there is a lack of monitoring tools to prove the success of these programs in real-time. Field-cage tests were conducted under the environmental conditions of the Mediterranean coast of Spain to estimate: (a) the mating success of sterile Vienna-8 (V8) Ceratitis capitata males using molecular markers and (b) their efficacy to reduce C. capitata populations under six release ratios of wild females to wild males to V8 males (1:0:0, 1:1:0, 1:1:1, 1:1:5, 1:1:10, and 1:1:20). Statistical models were developed to predict: (a) the number of females captured in traps, (b) sperm ID (sterile or not) in spermathecae of the trapped females, and (c) the viable offspring produced, using release ratio and temperature as predictors. The number of females captured was affected by relative humidity. However, its influence in the model was low. Female captures were significantly higher in ratios 1:0:0 compared to ratios where V8 males were released. The proportion of V8 sperm in spermathecae increased with temperature and with the number of V8 males released, but leveled off between ratios 1:1:10 and 1:1:20. In all seasons, except winter (no offspring), viable offspring increased with temperature and was lowest for ratio 1:1:20. For the first time, a strong negative relationship between proportion of V8 sperm detected by molecular tools and C. capitata offspring was established. The models obtained should contribute to enhance the efficacy of SIT programs against this pest.

  3. Male sterility and hybrid seed production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sexual reproduction in angiosperms is a complex process that includes a portion of the vegetative generation and all of the sexual generation. Coordination of both female and male reproduction ontogenies must occur. An abnormality anywhere in this process may lead to sterility. Genetic (nuclear) and...

  4. Age-Dependent Male Mating Investment in Drosophila pseudoobscura

    PubMed Central

    Dhole, Sumit; Pfennig, Karin S.

    2014-01-01

    Male mating investment can strongly influence fitness gained from a mating. Yet, male mating investment often changes with age. Life history theory predicts that mating investment should increase with age, and males should become less discriminatory about their mate as they age. Understanding age-dependent changes in male behavior and their effects on fitness is important for understanding how selection acts in age-structured populations. Although the independent effects of male or female age have been studied in many species, how these interact to influence male mating investment and fitness is less well understood. We mated Drosophila pseudoobscura males of five different age classes (4-, 8-, 11-, 15-, 19-day old) to either young (4-day) or old (11-day) females, and measured copulation duration and early post-mating fecundity. Along with their independent effects, we found a strong interaction between the effects of male and female ages on male mating investment and fitness from individual matings. Male mating investment increased with male age, but this increase was more prominent in matings with young females. Male D. pseudoobscura made smaller investments when mating with old females. The level of such discrimination based on female age, however, also changed with male age. Intermediate aged males were most discriminatory, while the youngest and the oldest males did not discriminate between females of different ages. We also found that larger male mating investments resulted in higher fitness payoffs. Our results show that male and female ages interact to form a complex pattern of age-specific male mating investment and fitness. PMID:24586373

  5. Molecular analysis of cytoplasmic male sterility

    SciTech Connect

    Hanson, M.R.

    1990-01-01

    The ultimate aims of the project are to understand the molecular mechanism of the disruption in pollen development which occurs in cytoplasmic male sterile plants and to understand the control of respiratory energy flow in the higher plant cell. A mitochondrial locus termed S-pcf segregates with sterility and with an alteration in respiration in Petunia. This cloned locus contains three genes, an abnormal fused gene termed pcf, a gene for a subunit of an NADH dehydrogenase complex, and a small ribosomal subunit protein. The pcf gene is comprised of partial sequences of ATPase subunit 9, cytochrome oxidase subunit II, and an unidentified reading frame. Components of the S-Pcf locus will be introduced into the nuclear of a fertile genotype under the control of appropriate regulatory signals, and polypeptide products of introduced genes will be directed to the mitochondrion with a transit peptide. By examining transgenic plants, we can determine what elements of the locus are critical for altered respiration or sterility. Such knowledge could explain how mitochondrial DNA affects pollen development in the large number of plant species which exhibit the agronomically important trait of male sterility. 10 refs., 3 figs.

  6. Modeling ephemeral mating encounters in insects: The emergence of mate-finding Allee effects and applications to theoretical models of sterile release.

    PubMed

    Gordillo, Luis F

    2015-09-01

    Lack of successful mating encounters in two-sex insect populations is a mechanism that might trigger reproductive Allee effects. In this paper I examine a function that models ephemeral mating encounters through the expected density of pairs formed by individuals of both sexes at any time. When this function is incorporated in a general system of differential equations for a two-sex population the solutions exhibit the emergence of an Allee effect for low population densities. Compared with current conceptual models for mate-finding Allee effects, the proposed pairing function does not include a parameter that quantifies the Allee effect strength, a feature that might be useful when information to parameterize Allee effects is unavailable. The mating function is then used to numerically explore how mate-finding Allee effects are enhanced by the release of sterile males in theoretical models where (i) the initial sex ratio is skewed, (ii) sterile males are released in pulses and (iii) partial female remating is allowed.

  7. Gamma ray dosimetry and mating capacity studies in the laboratory on Aedes albopictus males.

    PubMed

    Balestrino, F; Medici, A; Candini, G; Carrieri, M; Maccagnani, B; Calvitti, M; Maini, S; Bellini, R

    2010-07-01

    In Italy, Aedes albopictus Skuse is currently recognized as the most dangerous mosquito, and as currently applied conventional control methods gave unsatisfactory results, we are developing alternative strategies such as the sterile insect technique. To find the optimal sterilizing dose, male pupae were exposed to different doses of gamma rays in the range 20-80 Gy, generated by a Cesium-137 source. The effects of male pupal age at irradiation and gamma ray dose on adult male emergence, sterility level, longevity, and mating capacity were evaluated, and dose-response curves of residual fertility were calculated. Radiation tests were also performed on female pupae to observe their reproductive capacity in case of accidental release. Results confirmed that the age at which the male pupa is irradiated is an important factor that affects the longevity of the adult, whereas the effect of age on the induced sterility level is less pronounced. When male pupae older than 30 h were irradiated, the longevity of the adults was not affected by doses up to 40 Gy. The 40-Gy dose appeared sufficient to induce high level of sterility (>99%) at any male pupal age for all the strains tested. The duration of coupling and the number of mated females per male appeared to be affected by the radiation received by male pupae only at doses higher than 40 Gy. The female pupae were more sensitive to radiation than male pupae, with strong reduction in fecundity and fertility at 20 Gy and complete suppression of oviposition at higher doses.

  8. Research to support sterile-male-release and genetic alteration techniques for sea lamprey control

    USGS Publications Warehouse

    Bergstedt, Roger A.; Twohey, Michael B.

    2007-01-01

    Integrated pest management of sea lampreys in the Laurentian Great Lakes has recently been enhanced by addition of a sterile-male-release program, and future developments in genetic approaches may lead to additional methods for reducing sea lamprey reproduction. We review the development, implementation, and evaluation of the sterile-male-release technique (SMRT) as it is being applied against sea lampreys in the Great Lakes, review the current understanding of SMRT efficacy, and identify additional research areas and topics that would increase either the efficacy of the SMRT or expand its geographic potential for application. Key areas for additional research are in the sterilization process, effects of skewed sex ratios on mating behavior, enhancing attractiveness of sterilized males, techniques for genetic alteration of sea lampreys, and sources of animals to enhance or expand the use of sterile lampreys.

  9. Development of male-sterile lines for breeding hybrid rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice is a self-pollinated crop that depends on male-sterility for F1 hybrid seed production. As an alternative to accessing existing male-sterile lines from other hybrid breeding programs, the program in Arkansas has created its own novel male-sterile sources. These were developed out of germplasm...

  10. Suppression of Pest Lepidoptera by Releasing Partially Sterile Males

    ERIC Educational Resources Information Center

    Knipling. E. F.

    1970-01-01

    Uses population growth models to calculate the theoretical suppression of reproduction achieved by releasing irradiated male moths carrying genetic sterility factors. Shows that releasing partially sterile males should be more effective than releasing fully sterile males. Discusses the costs and advantages of applying this approach to the control…

  11. Evaluation of radiation sensitivity and mating performance of Glossina brevipalpis males

    PubMed Central

    Moyaba, Percy; Boikanyo, Solomon N. B.; Majatladi, Daphney; Yamada, Hanano; Venter, Gert J.; Vreysen, Marc J. B.

    2017-01-01

    Background Area-wide integrated pest management strategies that include a sterile insect technique component have been successfully used to eradicate tsetse fly populations in the past. To ensure the success of the sterile insect technique, the released males must be adequately sterile and be able to compete with their native counterparts in the wild. Methodology/Principal findings In the present study the radiation sensitivity of colonised Glossina brevipalpis Newstead (Diptera; Glossinidae) males, treated either as adults or pupae, was assessed. The mating performance of the irradiated G. brevipalpis males was assessed in walk-in field cages. Glossina brevipalpis adults and pupae were highly sensitive to irradiation, and a dose of 40 Gy and 80 Gy induced 93% and 99% sterility respectively in untreated females that mated with males irradiated as adults. When 37 to 41 day old pupae were exposed to a dose of 40 Gy, more than 97% sterility was induced in untreated females that mated with males derived from irradiated pupae. Males treated as adults with a dose up to 80 Gy were able to compete successfully with untreated fertile males for untreated females in walk-in field cages. Conclusions/Significance The data emanating from this field cage study indicates that, sterile male flies derived from the colony of G. brevipalpis maintained at the Agricultural Research Council-Onderstepoort Veterinary Institute in South Africa are potential good candidates for a campaign that includes a sterile insect technique component. This would need to be confirmed by open field studies. PMID:28306730

  12. Methyl eugenol aromatherapy enhances the mating competitiveness of male Bactrocera carambolae Drew & Hancock (Diptera: Tephritidae).

    PubMed

    Haq, Ihsan; Vreysen, Marc J B; Cacéres, Carlos; Shelly, Todd E; Hendrichs, Jorge

    2014-09-01

    Males of Bactrocera carambolae Drew & Hancock (Diptera: Tephritidae) are strongly attracted to methyl eugenol (ME) (1,2-dimethoxy-4-(2-propenyl)benzene), a natural compound occurring in variety of plant species. ME-feeding is known to enhance male B. carambolae mating competitiveness 3 days after feeding. Enhanced male mating competitiveness due to ME-feeding can increase the effectiveness of sterile insect technique (SIT) manifolds. However, the common methods for emergence and holding fruit flies prior to field releases do not allow the inclusion of any ME feeding treatment after fly emergence. Therefore this study was planned to assess the effects of ME-aromatherapy in comparison with ME feeding on male B. carambolae mating competitiveness as aromatherapy is pragmatic for fruit flies emergence and holding facilities. Effects of ME application by feeding or by aromatherapy for enhanced mating competitiveness were evaluated 3d after treatments in field cages. ME feeding and ME aromatherapy enhanced male mating competitiveness as compared to untreated males. Males treated with ME either by feeding or by aromatherapy showed similar mating success but mating success was significantly higher than that of untreated males. The results are discussed in the context of application of ME by aromatherapy as a pragmatic approach in a mass-rearing facility and its implications for effectiveness of SIT.

  13. Density affects mating mode and large male mating advantage in a fiddler crab.

    PubMed

    Ribeiro, Pablo D; Daleo, Pedro; Iribarne, Oscar O

    2010-12-01

    Fiddler crabs show two different mating modes: either females search and crabs mate underground in male burrows, or males search and crabs mate on the surface near female burrows. We explored the relationship between crab density, body size, the searching behavior of both sexes, and the occurrence of both mating modes in the fiddler crab Uca uruguayensis. We found that crabs change their mating mode depending on their size and crab density. Crabs mated mostly on the surface at low densities, and underground at high densities. The proportion of wandering receptive females but not courting males accounted for the variation in mating modes. This suggests that whether crabs mate underground (or on the surface) is determined by the presence (or absence) of searching females. We found that the change in the mating mode affected the level of assortative mating; males mating underground were bigger than those mating on the surface, suggesting active female choice. Given that fiddler crabs experience multiple reproductive cycles, they are prone to showing behavioral plasticity in their mating strategy whenever the payoffs of using different mating modes differ between reproductive events. Our results suggest that the incorporation of different levels of environmental variability may be important in theoretical models aimed at improving our understanding of the evolution of alternative mating tactics and strategies.

  14. Partial male sterility and the evolution of nuclear gynodioecy in plants.

    PubMed

    Schultz, Stewart T

    2002-12-01

    Gynodioecy, a genetic dimorphism of females and hermaphrodites, is pertinent to an understanding of the evolution of plant gender, mating and genetic variability. Classical models of nuclear gynodioecy attribute the maintenance of the dimorphism to frequency-dependent selection in which the female phenotype has a fitness advantage at low frequency owing to a doubled ovule fertility. Here, I analyse explicit genetic models of nuclear gynodioecy that expand on previous work by allowing partial male sterility in combination with either fixed or dynamically evolving mutational inbreeding depression. These models demonstrate that partial male sterility causes fitness underdominance at the mating locus, which can prevent the spread of females. However, if partial male sterility is compensated by a change in selfing rate, overdominance at the mating locus can cause the spread of females. Overdominance at introduction of the male sterility allele can be caused by high inbreeding depression and a lower selfing rate in the heterozygote, by purging of mutations by a higher selfing rate in the heterozygote, and by low inbreeding depression and a higher selfing rate in the heterozygote. These processes might be of general importance in the maintenance of mating polymorphisms in plants.

  15. Mating and male pheromone kill Caenorhabditis males through distinct mechanisms

    PubMed Central

    Shi, Cheng; Runnels, Alexi M; Murphy, Coleen T

    2017-01-01

    Differences in longevity between sexes is a mysterious yet general phenomenon across great evolutionary distances. To test the roles of responses to environmental cues and sexual behaviors in longevity regulation, we examined Caenorhabditis male lifespan under solitary, grouped, and mated conditions. We find that neurons and the germline are required for male pheromone-dependent male death. Hermaphrodites with a masculinized nervous system secrete male pheromone and are susceptible to male pheromone killing. Male pheromone-mediated killing is unique to androdioecious Caenorhabditis, and may reduce the number of males in hermaphroditic populations; neither males nor females of gonochoristic species are susceptible to male pheromone killing. By contrast, mating-induced death, which is characterized by germline-dependent shrinking, glycogen loss, and ectopic vitellogenin expression, utilizes distinct molecular pathways and is shared between the sexes and across species. The study of sex- and species-specific regulation of aging reveals deeply conserved mechanisms of longevity and population structure regulation. DOI: http://dx.doi.org/10.7554/eLife.23493.001 PMID:28290982

  16. Reduction in sea lamprey hatching success due to release of sterilized males

    USGS Publications Warehouse

    Bergstedt, Roger A.; McDonald, Rodney B.; Twohey, Michael B.; Mullett, Katherine M.; Young, Robert J.; Heinrich, John W.

    2003-01-01

    Male sea lampreys (Petromyzon marinus), sterilized by injection with bisazir, were released in Lake Superior tributaries from 1991 to 1996 and exclusively in the St. Marys River (the outflow from Lake Superior to Lake Huron) since 1997 as an alternative to chemical control. To determine effectiveness in reducing reproductive potential through the time of hatch, males were observed on nests and egg viability was determined in nests in selected Lake Superior tributaries and the St. Marys River. The proportions of sterilized males observed on nests were not significantly different than their estimated proportion in the population for all streams and years combined or for the St. Marys River alone. It was concluded that sterilized males survive, appear on the spawning grounds, and nest at near their estimated proportion in the population. There was a significant reduction in egg viability corresponding with release of sterilized males for all streams and years combined or for the St. Marys River alone. In the St. Marys River from 1993 to 2000, the percent reduction in egg viability was significantly correlated with the observed proportion of sterile males on nests. It was further concluded that sterilized males remain sterile through nesting and attract and mate with females. Reduction in reproductive potential in the St. Marys River due to both removal of females by traps and sterile-male-release ranged from 34 to 92% from 1993 to 2001 and averaged 64%. From 1999 to 2001, when the program stabilized, reductions ranged from 71 to 92% and averaged 81%. The current release of sterile males in the St. Marys River effectively reduced reproductive potential through the time of hatch and did so near theoretical levels based on numbers released, estimates of population size, and the assumptions of full sterility and competitiveness.

  17. Mitochondria and cytoplasmic male sterility in plants.

    PubMed

    Hu, Jun; Huang, Wenchao; Huang, Qi; Qin, Xiaojian; Yu, Changchun; Wang, Lili; Li, Shaoqing; Zhu, Renshan; Zhu, Yingguo

    2014-11-01

    Mitochondria are essential organelles in cells not only because they supply over 90% of the cell's energy but also because their dysfunction is associated with disease. Owing to the importance of mitochondria, there are many questions about mitochondria that must be answered. Cytoplasmic male sterility (CMS) is a mysterious natural phenomenon, and the mechanism of the origin of CMS is unknown. Despite successful utilization of CMS and restoration of fertility (Rf) in practice, the underlying mechanisms of these processes remain elusive. This review summarizes the genes involved in CMS and Rf, with a special focus on recent studies reporting the mechanisms of the CMS and Rf pathways, and concludes with potential working models.

  18. Male motion coordination in anopheline mating swarms

    PubMed Central

    Shishika, Daigo; Manoukis, Nicholas C.; Butail, Sachit; Paley, Derek A.

    2014-01-01

    The Anopheles gambiae species complex comprises the primary vectors of malaria in much of sub-Saharan Africa. Most of the mating in these species occurs in swarms composed almost entirely of males. Intermittent, organized patterns in such swarms have been observed, but a detailed description of male-male interactions has not previously been available. We identify frequent, time-varying interactions characterized by periods of parallel flight in data from 8 swarms of Anopheles gambiae and 3 swarms of Anopheles coluzzii filmed in 2010 and 2011 in the village of Donéguébogou, Mali. We use the cross correlation of flight direction to quantify these interactions and to induce interaction graphs, which show that males form synchronized subgroups whose size and membership change rapidly. A swarming model with damped springs between each male and the swarm centroid shows good agreement with the correlation data, provided that local interactions represented by damping of relative velocity between males are included. PMID:25212874

  19. Defective pollen wall contributes to male sterility in the male sterile line 1355A of cotton

    PubMed Central

    Wu, Yuanlong; Min, Ling; Wu, Zancheng; Yang, Li; Zhu, Longfu; Yang, Xiyan; Yuan, Daojun; Guo, Xiaoping; Zhang, Xianlong

    2015-01-01

    To understand the mechanisms of male sterility in cotton (Gossypium spp.), combined histological, biochemical and transcription analysis using RNA-Seq was carried out in the anther of the single-gene recessive genic male sterility system of male sterile line 1355A and male fertile line 1355B, which are near-isogenic lines (NILs) differing only in the fertility trait. A total of 2,446 differentially expressed genes were identified between the anthers of 1355AB lines, at three different stages of development. Cluster analysis and functional assignment of differentially expressed genes revealed differences in transcription associated with pollen wall and anther development, including the metabolism of fatty acids, glucose, pectin and cellulose. Histological and biochemical analysis revealed that a major cellular defect in the 1355A was a thicker nexine, consistent with the RNA-seq data, and further gene expression studies implicated differences in fatty acids synthesis and metabolism. This study provides insight into the phenotypic characteristics and gene regulatory network of the genic male sterile line 1355A in upland cotton. PMID:26043720

  20. A character demonstrating the occurrence of mating in male Cactoblastis cactorum (Lepidoptera: Pyralidae)

    SciTech Connect

    Marti, O.G.; Carpenter, J.E.

    2007-03-15

    The reproductive system of adult male Cactoblastis cactorum, the cactus moth, was examined to determine whether the mating status of males could be ascertained. In unmated males, the posterior portion of the primary ductus ejaculatorius simplex is opaque yellow in color and contains many small football-shaped hyaline granules 3-5 x 5-10 {mu}m in size. In mated males, the posterior simplex is clear and contains no granules. The presence or absence of these characters was found to be highly reliable and should be of value in determining mating status in marked-recaptured males of this species in a sterile insect release program directed against Cactoblastis. (author)

  1. Optimizing methyl-eugenol aromatherapy to maximize posttreatment effects to enhance mating competitiveness of male Bactrocera carambolae (Diptera: Tephritidae).

    PubMed

    Haq, Ihsan ul; Vreysen, Marc J B; Cacéres, Carlos; Shelly, Todd E; Hendrichs, Jorge

    2015-10-01

    Methyl-eugenol (ME) (1,2-dimethoxy-4-(2-propenyl)benzene), a natural phytochemical, did enhance male Bactrocera carambolae Drew & Hancock (Diptera: Tephritidae) mating competitiveness 3 d after ingestion. Enhanced male mating competitiveness can significantly increase the effectiveness of the sterile insect technique (SIT). ME application to mass reared sterile flies by feeding is infeasible. ME application by aromatherapy however, would be a very practical way of ME application in fly emergence and release facilities. This approach was shown to enhance mating competitiveness of B. carambolae 3 d posttreatment (DPT). Despite this added benefit, every additional day of delaying release will reduce sterile fly quality and will add cost to SIT application. The present study was planned to assess the effects of ME-aromatherapy on male B. carambolae mating competitiveness 1DPT and 2DPT. ME aromatherapy 1DPT or 2DPT did enhance mating competitiveness of B. carambolae males whereas ME feeding 1DPT and 2DPT did not. Male mating competitiveness was enhanced by the ME aromatherapy irrespective if they received 1DPT, 2DPT or 3DPT. ME aromatherapy, being a viable approach for its application, did enhance mating competitiveness of male B. carambolae 1 d posttreatment as ME feeding did 3 d after ingestion.

  2. Cytoplasmic male sterility in Brassicaceae crops.

    PubMed

    Yamagishi, Hiroshi; Bhat, Shripad R

    2014-05-01

    Brassicaceae crops display strong hybrid vigor, and have long been subject to F1 hybrid breeding. Because the most reliable system of F1 seed production is based on cytoplasmic male sterility (CMS), various types of CMS have been developed and adopted in practice to breed Brassicaceae oil seed and vegetable crops. CMS is a maternally inherited trait encoded in the mitochondrial genome, and the male sterile phenotype arises as a result of interaction of a mitochondrial CMS gene and a nuclear fertility restoring (Rf) gene. Therefore, CMS has been intensively investigated for gaining basic insights into molecular aspects of nuclear-mitochondrial genome interactions and for practical applications in plant breeding. Several CMS genes have been identified by molecular genetic studies, including Ogura CMS from Japanese radish, which is the most extensively studied and most widely used. In this review, we discuss Ogura CMS, and other CMS systems, and the causal mitochondrial genes for CMS. Studies on nuclear Rf genes and the cytoplasmic effects of alien cytoplasm on general crop performance are also reviewed. Finally, some of the unresolved questions about CMS are highlighted.

  3. The dance of male Anopheles gambiae in mating swarms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mating behavior of the malaria vector Anopheles gambiae is of great interest from a fundamental and applied perspective. One of the most important elements of mating in this species is the crepuscular mating aggregation (swarm) composed almost entirely of males, where most coupling and inseminat...

  4. Mass Rearing History and Irradiation Affect Mating Performance of the Male Fruit Fly, Anastrepha obliqua

    PubMed Central

    Rull, Juan; Encarnación, Nery; Birke, Andrea

    2012-01-01

    As an initial step to improve the efficiency of the sterile insect technique applied to eradicate, suppress, and control wild Anastrepha obliqua (Macquart) (Diptera: Tephritidae) in mango producing areas of Mexico, the effect of radiation dose and mass rearing history on male mating performance was examined. Field cage tests in which both male and female laboratory flies were irradiated at different doses (0, 40, and 80 Gy) were released with cohorts of wild flies of both sexes, revealing that both mass rearing history and irradiation affected male mating performance. Laboratory males were accepted for copulation by wild females less frequently than wild males. Copulations involving laboratory males were shorter than those involving wild males. Irradiated males mated less frequently with wild females than wild males, and irradiated females appeared to be less able to reject courting males of both origins. High levels of fertility for untreated laboratory females crossed with males irradiated at different doses may reflect problems in mass rearing affecting homogeneity of pupal age before irradiation, and possibly masked a dose effect. Proposed remedial measures to improve male mating performance are discussed. PMID:22957485

  5. Comparison of Irradiation and Wolbachia Based Approaches for Sterile-Male Strategies Targeting Aedes albopictus

    PubMed Central

    Atyame, Célestine M.; Labbé, Pierrick; Lebon, Cyrille; Weill, Mylène; Moretti, Riccardo; Marini, Francesca; Gouagna, Louis Clément; Calvitti, Maurizio; Tortosa, Pablo

    2016-01-01

    The global expansion of Aedes albopictus together with the absence of vaccines for most of the arboviruses transmitted by this mosquito has stimulated the development of sterile-male strategies aiming at controlling disease transmission through the suppression of natural vector populations. In this context, two environmentally friendly control strategies, namely the Sterile Insect Technique (SIT) and the Wolbachia-based Incompatible Insect Technique (IIT) are currently being developed in several laboratories worldwide. So far however, there is a lack of comparative assessment of these strategies under the same controlled conditions. Here, we compared the mating capacities, i.e. insemination capacity, sterilization capacity and mating competitiveness of irradiated (35 Gy) and incompatible Ae. albopictus males at different ages and ratios under laboratory controlled conditions. Our data show that there was no significant difference in insemination capacity of irradiated and incompatible males, both male types showing lower capacities than untreated males at 1 day but recovering full capacity within 5 days following emergence. Regarding mating competitiveness trials, a global observed trend is that incompatible males tend to induce a lower hatching rate than irradiated males in cage controlled confrontations. More specifically, incompatible males were found more competitive than irradiated males in 5:1 ratio regardless of age, while irradiated males were only found more competitive than incompatible males in the 1:1 ratio at 10 days old. Overall, under the tested conditions, IIT seemed to be slightly more effective than SIT. However, considering that a single strategy will likely not be adapted to all environments, our data stimulates the need for comparative assessments of distinct strategies in up-scaled conditions in order to identify the most suitable and safe sterilizing technology to be implemented in a specific environmental setting and to identify the

  6. Comparison of Irradiation and Wolbachia Based Approaches for Sterile-Male Strategies Targeting Aedes albopictus.

    PubMed

    Atyame, Célestine M; Labbé, Pierrick; Lebon, Cyrille; Weill, Mylène; Moretti, Riccardo; Marini, Francesca; Gouagna, Louis Clément; Calvitti, Maurizio; Tortosa, Pablo

    2016-01-01

    The global expansion of Aedes albopictus together with the absence of vaccines for most of the arboviruses transmitted by this mosquito has stimulated the development of sterile-male strategies aiming at controlling disease transmission through the suppression of natural vector populations. In this context, two environmentally friendly control strategies, namely the Sterile Insect Technique (SIT) and the Wolbachia-based Incompatible Insect Technique (IIT) are currently being developed in several laboratories worldwide. So far however, there is a lack of comparative assessment of these strategies under the same controlled conditions. Here, we compared the mating capacities, i.e. insemination capacity, sterilization capacity and mating competitiveness of irradiated (35 Gy) and incompatible Ae. albopictus males at different ages and ratios under laboratory controlled conditions. Our data show that there was no significant difference in insemination capacity of irradiated and incompatible males, both male types showing lower capacities than untreated males at 1 day but recovering full capacity within 5 days following emergence. Regarding mating competitiveness trials, a global observed trend is that incompatible males tend to induce a lower hatching rate than irradiated males in cage controlled confrontations. More specifically, incompatible males were found more competitive than irradiated males in 5:1 ratio regardless of age, while irradiated males were only found more competitive than incompatible males in the 1:1 ratio at 10 days old. Overall, under the tested conditions, IIT seemed to be slightly more effective than SIT. However, considering that a single strategy will likely not be adapted to all environments, our data stimulates the need for comparative assessments of distinct strategies in up-scaled conditions in order to identify the most suitable and safe sterilizing technology to be implemented in a specific environmental setting and to identify the

  7. Investigation of methods for sterilization of potting compounds and mated surfaces

    NASA Technical Reports Server (NTRS)

    Tulius, J. J.; Daley, D. J.; Phillips, G. B.

    1972-01-01

    The feasibility of using formaldehyde-liberating synthetic resins or polymers for the sterilization of potting compounds, mated and occluded areas, and spacecraft surfaces was demonstrated. The detailed study of interrelated parameters of formaldehyde gas sterilization revealed that efficient cycle conditions can be developed for the sterilization of spacecraft components. It was determined that certain parameters were more important than others in the development of cycles for specific applications. The use of formaldehyde gas for the sterilization of spacecraft components provides NASA with a highly efficient method which is inexpensive, reproducible, easily quantitated, materials compatible, operationally simple, generally non-hazardous and not thermally destructive.

  8. Uncoupling the links between male mating tactics and female attractiveness.

    PubMed Central

    Ojanguren, Alfredo F; Magurran, Anne E

    2004-01-01

    Because not all females are equally attractive, and because mating reduces the chances of getting further copulations, males should prefer better-quality mates. In this paper, we use the Trinidadian guppy (Poecilia reticulata) to explore the effects of two non-correlated measures of female quality--size and reproductive status--on male mating decisions. All male guppies employ two alternative mating tactics. We found that large females, particularly those from a high predation site, were the target of most sneaky mating attempts. The response persisted in fish raised under standard conditions over several generations in the laboratory. In addition, non-pregnant females received more courtship displays. We conclude that males can discriminate among females and that they uncouple their mating tactics to track different axes of quality. PMID:15801594

  9. Costs influence male mate choice in a freshwater fish.

    PubMed Central

    Wong, Bob B M; Jennions, Michael D

    2003-01-01

    It is well known that female mate choice decisions depend on the direct costs of choosing (either because of search costs or male-imposed costs). Far less is known about how direct fitness costs affect male mate choice. We conducted an experiment to investigate male mate choice in a fish, the Pacific blue-eye (Pseudomugil signifer). Preferred females were larger, probably because larger females are also more fecund. Males, however, were consistent in their choice of female only when the costs of associating with prospective mates were equal. By contrast, males were far less consistent in their choice when made to swim against a current to remain with their initially preferred mate. Our results suggest that males may also respond adaptively to changes in the costs of choosing. PMID:12952630

  10. A New Adult Diet Formulation for Sterile Males of Anastrepha ludens and Anastrepha obliqua (Diptera: Tephritidae).

    PubMed

    Orozco-Dávila, Dina; Quintero-Fong, Luis

    2015-08-01

    A new adult diet formulation was evaluated for sterile Anastrepha ludens (Loew) and Anastrepha obliqua (Macquart) males at the emergence and release facility of fruit flies in Mexico. The formulation consists of hydrolyzed protein, sugar, juvenile hormone analogue methoprene, and water. The proportion of the ingredients between the solute (4% hydrolyzed protein and 96% sugar) and solvent (10% methoprene and 90% water) was 5:1. This new formulation was called the 1:24 formulation. The main objectives of this study were to develop a simple way to supply the 1:24 formulation to adults and to compare the sexual performance of these flies with the performance of flies fed a standard diet (called the Mubarqui formulation) used at the emergence and release facility of fruit flies in Mexico. The preparation, time, and cost also were evaluated. The results showed no significant differences in the sexual behaviors of the males (number of males mating, number of males calling, mating latency, and mating duration) between the 1:24 formulation and the Mubarqui formulation. However, the cost and the required preparation time are much lower for the 1:24 formulation process than for the Mubarqui formulation process. Based on these results, we recommend the 1:24 formulation as an additional adult diet option in the handling of sterile flies. Its application is practical and does not require changes in packaging systems. The contribution of our findings and their potential application to the improvement of the sterile insect technique are discussed.

  11. Associations between body morphology, mating success and mate preferences among Slovak males and females.

    PubMed

    Prokop, Pavol; Fedor, Peter

    2013-01-01

    Human body morphology is thought to be correlated with sexual behaviour and sociosexuality (defined as an increased willingness to engage in sex without commitment) influences the perception of certain cues of physical attractiveness. Based on a sample of Slovak university students, we investigated relationships between 1) male and female mating success and reported body morphology (body mass index, BMI and waist-to-hip ratio, WHR) and 2) mate preference characteristics and mating success. Both males and females reported a similar number of long-term sexual partners and frequency of engaging in extra-pair copulation (EPC). The mating success of both sexes was positively mediated by self-perceived attractiveness. However, female BMI was inversely associated with mating success whereas increasing BMI was positively associated with male mating success (the total number of lifetime sexual partners) as well as with the likelihood of engaging in EPC. Unrestricted sociosexuality positively correlated with direct and indirect benefits from mating and negatively with the religious/political background of a potential mate and with the desire for a home/ children. These results confirm the hypothesis that human body morphology is associated with sexual behaviour and that cues of direct/indirect benefits in a potential mate positively correlate with sociosexuality.

  12. Effect of Mating Status and Age on the Male Mate Choice and Mating Competency in the Common Bed Bug, Cimex lectularius (Hemiptera: Cimicidae).

    PubMed

    Wang, Desen; Wang, Changlu; Singh, Narinderpal; Cooper, Richard; Zha, Chen; Eiden, Amanda L

    2016-04-28

    We investigated male mate choice and mating competency in the common bed bug, Cimex lectularius L., using video tracking for 10 min per experiment. In the male mate choice experiment, when a male was placed with two females of different mating status, males preferred to initiate copulation with the virgin female more quickly than with the mated female, and the mean total copulation duration with virgin females (38.0 ± 3.0 s) was significantly longer than with mated females (14.6 ± 3.0 s). When a male was placed with two females of different age, males initiated copulation more quickly with the old virgin female (29-34 d adult emergence) than with the young virgin one (<7 d adult emergence), and the mean total copulation duration with old virgin females (38.4 ± 4.0 s) was significantly longer than with young virgin females (24.0 ± 3.0 s). In the male mating competency experiment where a female was placed with two males of different mating status or age, the virgin males were more eager to mate than the mated males, and the old virgin males (29-34 d adult emergence) were more eager than the young virgin males (<7 d adult emergence), with eagerness measured by the percentage of first mate selected (first copulation occurred) and the total copulation duration by each group of males. Male mating competency is related to postmating duration (PMD); males mated 1 d earlier were significantly less likely to mate than virgin males. However, males mated 7 d earlier showed no significant difference in mating competency compared to virgin males. In conclusion, mate choice in C. lectularius is associated with both male and female mating status, age, and PMD.

  13. Sterility and Sexual Competitiveness of Tapachula-7 Anastrepha ludens Males Irradiated at Different Doses.

    PubMed

    Orozco-Dávila, Dina; Adriano-Anaya, Maria de Lourdes; Quintero-Fong, Luis; Salvador-Figueroa, Miguel

    2015-01-01

    A genetic sexing strain of Anastrepha ludens (Loew), Tapachula-7, was developed by the Mexican Program Against Fruit Flies to produce and release only males in programs where the sterile insect technique (SIT) is applied. Currently, breeding are found at a massive scale, and it is necessary to determine the optimum irradiation dose that releases sterile males with minimum damage to their sexual competitiveness. Under laboratory and field conditions, we evaluated the effects of gamma irradiation at doses of 0, 20, 40, 60 and 80 Gy on the sexual competitiveness of males, the induction of sterility in wild females and offspring survivorship. The results of the study indicate that irradiation doses have a significant effect on the sexual behavior of males. A reduction of mating capacity was inversely proportional to the irradiation dose of males. It is estimated that a dose of 60 Gy can induce more than 99% sterility in wild females. In all treatments, the degree of offspring fertility was correlated with the irradiation dose of the parents. In conclusion, the results of the study indicate that a dose of 60 Gy can be applied in sterile insect technique release programs. The application of this dose in the new genetic sexing strain of A. ludens is discussed.

  14. Sterility and Sexual Competitiveness of Tapachula-7 Anastrepha ludens Males Irradiated at Different Doses

    PubMed Central

    Orozco-Dávila, Dina; Adriano-Anaya, Maria de Lourdes; Quintero-Fong, Luis; Salvador-Figueroa, Miguel

    2015-01-01

    A genetic sexing strain of Anastrepha ludens (Loew), Tapachula-7, was developed by the Mexican Program Against Fruit Flies to produce and release only males in programs where the sterile insect technique (SIT) is applied. Currently, breeding are found at a massive scale, and it is necessary to determine the optimum irradiation dose that releases sterile males with minimum damage to their sexual competitiveness. Under laboratory and field conditions, we evaluated the effects of gamma irradiation at doses of 0, 20, 40, 60 and 80 Gy on the sexual competitiveness of males, the induction of sterility in wild females and offspring survivorship. The results of the study indicate that irradiation doses have a significant effect on the sexual behavior of males. A reduction of mating capacity was inversely proportional to the irradiation dose of males. It is estimated that a dose of 60 Gy can induce more than 99% sterility in wild females. In all treatments, the degree of offspring fertility was correlated with the irradiation dose of the parents. In conclusion, the results of the study indicate that a dose of 60 Gy can be applied in sterile insect technique release programs. The application of this dose in the new genetic sexing strain of A. ludens is discussed. PMID:26274926

  15. Evidence for minority male mating success and minority female mating disadvantage in Drosophila ananassae.

    PubMed

    Som, Arundhati; Singh, Bashisth N

    2005-03-31

    Frequency-dependent mating success was tested for three pairs of wild-type and mutant strains of Drosophila ananassae, MY and yellow body color (y), PN and claret eye color (ca), and TIR and cut wing (ct). The two strains of each pair were chosen for their approximately equal mating propensities. Multiple-choice experiments, using different experimental procedures, were employed. The tests were carried out by direct observation in Elens-Wattiaux mating chambers with five different sex ratios (4:16, 8:12, 10:10, 12:8, and 16:4). There was no assortative mating and sexual isolation between the strains, based on 2 x 2 contingency chi2 analysis and isolation estimate values. One-sided rare male mating advantages were found in two experiments, one for ca males and the other for wild-type males (TIR). However, no advantage was found for rare males in the experiment with MY and y flies. Mating disadvantages for rare females were found for sex-linked mutants (y and ct). Two different observational methods (removal or direct observation of mating pairs) imparted no overall significant effects on the outcome of the frequency-dependent mating tests.

  16. Transcriptional regulation of male-sterility in 7B-1 male-sterile tomato mutant

    PubMed Central

    Omidvar, Vahid; Mohorianu, Irina; Dalmay, Tamas; Zheng, Yi; Fei, Zhangjun; Pucci, Anna; Mazzucato, Andrea; Večeřová, Vendula; Sedlářova, Michaela; Fellner, Martin

    2017-01-01

    The 7B-1 tomato (Solanum lycopersicum L. cv Rutgers) is a male-sterile mutant with enhanced tolerance to abiotic stress, which makes it a potential candidate for hybrid seed breeding and stress engineering. To underline the molecular mechanism regulating the male-sterility in 7B-1, transcriptomic profiles of the 7B-1 male-sterile and wild type (WT) anthers were studied using mRNA sequencing (RNA-Seq). In total, 768 differentially expressed genes (DEGs) were identified, including 132 up-regulated and 636 down-regulated transcripts. Gene ontology (GO) enrichment analysis of DEGs suggested a general impact of the 7B-1 mutation on metabolic processes, such as proteolysis and carbohydrate catabolic process. Sixteen candidates with key roles in regulation of anther development were subjected to further analysis using qRT-PCR and in situ hybridization. Cytological studies showed several defects associated with anther development in the 7B-1 mutant, including unsynchronized anther maturation, dysfunctional meiosis, arrested microspores, defect in callose degradation and abnormal tapetum development. TUNEL assay showed a defect in programmed cell death (PCD) of tapetal cells in 7B-1 anthers. The present study provides insights into the transcriptome of the 7B-1 mutant. We identified several genes with altered expression level in 7B-1 (including beta-1,3 glucanase, GA2oxs, cystatin, cysteine protease, pectinesterase, TA29, and actin) that could potentially regulate anther developmental processes, such as meiosis, tapetum development, and cell-wall formation/degradation. PMID:28178307

  17. Male mate preference and size-assortative mating in convict cichlids: A role for female aggression?

    PubMed

    Bloch, A N; Estela, V J; Leese, J M; Itzkowitz, M

    2016-09-01

    Many monogamous species demonstrate size-assortative mating patterns within natural populations. To better understand the role of intersexual selection in this process, we examined the effect of male preference for female body size in the convict cichlid (Amatitlania siquia). We provided males with a choice between females that differed in size, relative to each other and in relation to the focal male. Based on previous work, we expected males to prefer the largest available female mates across all treatments. Surprisingly, males spent more time near the smaller of two available females, but only when the other female was larger than the male. Additionally, males spent little time with either of two potential female mates when both females were larger than the male. We hypothesized that while males might prefer the largest of available females, female behavior might limit males from acting on this preference. To test this, males were force paired with a smaller or larger female. Pair formation only occurred when the female was smaller than the male, and females that were larger than their male counterparts showed significantly more aggression when compared to smaller females. Together, these data suggest that in the absence of intrasexual competition, male mate preference for large females in convict cichlids might be limited by female aggression.

  18. Construction of a male sterility system for hybrid rice breeding and seed production using a nuclear male sterility gene

    PubMed Central

    Chang, Zhenyi; Chen, Zhufeng; Wang, Na; Xie, Gang; Lu, Jiawei; Yan, Wei; Zhou, Junli; Tang, Xiaoyan; Deng, Xing Wang

    2016-01-01

    The breeding and large-scale adoption of hybrid seeds is an important achievement in agriculture. Rice hybrid seed production uses cytoplasmic male sterile lines or photoperiod/thermo-sensitive genic male sterile lines (PTGMS) as female parent. Cytoplasmic male sterile lines are propagated via cross-pollination by corresponding maintainer lines, whereas PTGMS lines are propagated via self-pollination under environmental conditions restoring male fertility. Despite huge successes, both systems have their intrinsic drawbacks. Here, we constructed a rice male sterility system using a nuclear gene named Oryza sativa No Pollen 1 (OsNP1). OsNP1 encodes a putative glucose–methanol–choline oxidoreductase regulating tapetum degeneration and pollen exine formation; it is specifically expressed in the tapetum and miscrospores. The osnp1 mutant plant displays normal vegetative growth but complete male sterility insensitive to environmental conditions. OsNP1 was coupled with an α-amylase gene to devitalize transgenic pollen and the red fluorescence protein (DsRed) gene to mark transgenic seed and transformed into the osnp1 mutant. Self-pollination of the transgenic plant carrying a single hemizygous transgene produced nontransgenic male sterile and transgenic fertile seeds in 1:1 ratio that can be sorted out based on the red fluorescence coded by DsRed. Cross-pollination of the fertile transgenic plants to the nontransgenic male sterile plants propagated the male sterile seeds of high purity. The male sterile line was crossed with ∼1,200 individual rice germplasms available. Approximately 85% of the F1s outperformed their parents in per plant yield, and 10% out-yielded the best local cultivars, indicating that the technology is promising in hybrid rice breeding and production. PMID:27864513

  19. Lifetime mating opportunities and male mating behaviour in sexually cannibalistic praying mantids.

    PubMed

    Maxwell

    1998-04-01

    I examined the number of lifetime mating opportunities and mating behaviour of males in two sexually cannibalistic species, the Mediterranean, Iris oratoria, and bordered, Stagmomantis limbata, praying mantids (Mantodea: Mantidae). Two approaches estimated the number of lifetime mating opportunities: direct observations of intersexual encounters in the field, and an encounter model. I collected behavioural observations, together with ecological data for use in the model, over three field seasons. The ecological data included an assessment of the feeding condition of S. limbata females in nature; the females fed at a level comparable to females maintained on an abundant diet in the laboratory. As for the number of mating opportunities, individual males of both species encountered two or more females, as predicted by the model. I observed no male, however, in more than one copulation. This result could reflect individual variation in the times and places of sexual activity or an actual low number of mating opportunities in the field. Furthermore, a higher percentage of I. oratoria males encountered two or more females than S. limbata males, as the model indicates. Fewer mating opportunities could lead to greater selection upon S. limbata males to ensure paternity at each mating, which can explain the longer copulation times observed for S. limbata males. I considered two hypotheses about male behaviour in light of the number of lifetime encounters with females: male suicide and male reduction of the risk of cannibalism. Behavioural observations do not strongly support male suicide in either species. Certain male behaviours, such as the nature of copulatory position and, in captivity, mounting females from the rear, are consistent with the idea that males behave so as to reduce the probability that they are cannibalized during intersexual encounters. Moreover, male I. oratoria preferentially mount well-fed, fecund females in captivity. Taken together, these results

  20. Time-pattern and frequency analyses of sounds produced by irradiated and untreated male Bactrocera tryoni (Froggatt) during mating behavior

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Behavior and sounds associated with mating of mass-reared irradiated and untreated (non-irradiated) Bactrocera tryoni (Froggatt) males were analyzed using synchronous acoustic and video recordings. The flies tested were from a population used in sterile release programs that help maintain fruit-fly...

  1. Strategic male mating effort and cryptic male choice in a scorpionfly.

    PubMed

    Engqvist, L; Sauer, K P

    2001-04-07

    In animal species with high male mating effort, males often find themselves in a dilemma: by increasing their mating effort, the gain from each copulation increases but simultaneously reduces available resources and, thus, the opportunity for future copulations. Therefore, we expect males to spend less reproductive resources on matings that provide low reproductive potential, thereby saving resources for future copulations, possibly with high-quality females, a sort of cryptic male choice. However, the strength of the trade-off between investment in a current mating and resources available for future matings must not be the same for all males. Males with relatively high mating costs should allocate their limited resources more cautiously than males with more plentiful resources. Here, we examine this prediction in the scorpionfly Panorpa cognata. Prior to copulation, males produce a large salivary mass on which females feed during copulation. We show that the production of larger salivary masses leads to longer copulations. Moreover, the size of the salivary gland and salivary mass increases with increasing male condition. However, males in poor condition make a relatively higher mating investment than males in good condition. We therefore expect male condition to influence cryptic male choice. In accordance with our hypothesis, only males in poor condition choose cryptically, producing larger salivary masses in copulations with females of high fecundity.

  2. Male coercive mating in externally fertilizing species: male coercion, female reluctance and explanation for female acceptance

    PubMed Central

    Matsumoto, Yukio; Takegaki, Takeshi

    2016-01-01

    Male coercive mating exerts a strong evolutionary pressure on mating-related traits of both sexes. However, it is extremely rare in externally fertilizing species probably because the male mating behaviour is incomplete until females release their eggs. Here we showed that males of the externally fertilizing fish Rhabdoblennius nitidus coercively confine females to the nests until spawning, and investigated why females accept male coercive mating. The females entered the males’ nests following male courtship displays, but they usually tried to escape when there were no eggs because males tended to cannibalize all the eggs when there were few. Most males that used small, tight nests acquired new eggs but with experimentally enlarged nests, 90% of the males without eggs failed to confine the females. Spawning tended to occur during the early/late spawning period in nests with no eggs (i.e. male coercive mating). In the nests where the first eggs were deposited in the early period, subsequent matings with other females were more likely to occur, whereas in the late period, most parental care of the eggs failed without additional matings. The females that spawned in the late period may have been compelled to accept male coercive mating due to time constraints. PMID:27087584

  3. Low-oxygen atmospheric treatment improves the performance of irradiation-sterilized male cactus moths used in SIT.

    PubMed

    López-Martínez, Giancarlo; Carpenter, James E; Hight, Stephen D; Hahn, Daniel A

    2014-02-01

    As part of sterile insect technique (SIT) programs, irradiation can effectively induce sterility in insects by damaging genomic DNA. However, irradiation also induces other off-target side effects that reduce the quality and performance of sterilized males. Thus, treatments that reduce off-target effects of irradiation on male performance while maintaining sterility can improve the feasibility and economy of SIT programs. Exposure to ionizing radiation induces the formation of damaging free radicals in biological systems that may reduce sterile male performance. Here, we test whether exposure to an anoxic environment for 1 h before and during irradiation improves male performance, while maintaining sterility in males of the cactus moth, Cactoblastis cactorum (Berg). We show that exposure to 1 h of anoxia increases the moth's antioxidant capacity and that irradiation in anoxia after 1 h of anoxic conditioning decreases irradiation-induced oxidative damage to the moth's lipids and proteins. Anoxia treatment that reduced oxidative damage after irradiation also produced moths with greater flight performance, mating success, and longevity, while maintaining F1 male sterility at acceptable levels for SIT. We conclude that anoxia pretreatment followed by irradiation in anoxia is an efficient way to improve the quality of irradiated moths and perhaps lower the number of moths needed for release SIT moth operations.

  4. Male mate choice and sperm allocation in a sexual/asexual mating complex of Poecilia (Poeciliidae, Teleostei)

    PubMed Central

    Schlupp, I; Plath, M

    2005-01-01

    Male mate choice is critical for understanding the evolution and maintenance of sexual/asexual mating complexes involving sperm-dependent, gynogenetic species. Amazon mollies (Poecilia formosa) require sperm to trigger embryogenesis, but the males (e.g. Poecilia mexicana) do not contribute genes. Males benefit from mating with Amazon mollies, because such matings make males more attractive to conspecific females, but they might control the cost of such matings by providing less sperm to Amazon mollies. We examined this at the behavioural and sperm levels. P. mexicana males preferred to mate with, and transferred more sperm to conspecific females. However, if males mated with P. formosa, sperm was readily transferred. This underscores the importance of male choice in this system. PMID:17148157

  5. Manipulation of the microbiota of mass-reared Mediterranean fruit flies Ceratitis capitata (Diptera: Tephritidae) improves sterile male sexual performance.

    PubMed

    Ben Ami, Eyal; Yuval, Boaz; Jurkevitch, Edouard

    2010-01-01

    The sterile insect technique (SIT) is a method of biological control whereby millions of factory reared sterile male insects are released into the field. This technique is commonly used to combat the Mediterranean fruit fly (Ceratitis capitata, Diptera: Tephritidae). Sterile medfly males are less competent in attracting and mating with wild females, a property commonly linked to the irradiation process responsible for the sterilization. As bacteria are important partners in the fly's life cycle, we used molecular analytical methods to study the community structure of the gut microbiota in irradiated male medflies. We find that the sterilizing irradiation procedure affects the gut bacterial community structure of the Mediterranean fruit fly. Although the Enterobacteriaceae family remains the dominant bacterial group present in the gut, the levels of Klebsiella species decreases significantly in the days after sterilization. In addition, we detected substantial differences in some bacterial species between the mass rearing strain Vienna 8 and the wild strain. Most notable among these are the increased levels of the potentially pathogenic species Pseudomonas in the industrial strain. Testing the hypothesis that regenerating the original microbiota community could result in enhanced competitiveness of the sterile flies, we found that the addition of the bacterial species Klebsiella oxytoca to the postirradiation diet enables colonization of these bacteria in the gut while resulting in decreased levels of the Pseudomonas sp. Feeding on diets containing bacteria significantly improved sterile male performance in copulatory tests. Further studies will determine the feasibility of bacterial amelioration in SIT operations.

  6. Polygyny, mate-guarding, and posthumous fertilization as alternative male mating strategies

    PubMed Central

    Zamudio, Kelly R.; Sinervo, Barry

    2000-01-01

    Alternative male mating strategies within populations are thought to be evolutionarily stable because different behaviors allow each male type to successfully gain access to females. Although alternative male strategies are widespread among animals, quantitative evidence for the success of discrete male strategies is available for only a few systems. We use nuclear microsatellites to estimate the paternity rates of three male lizard strategies previously modeled as a rock-paper-scissors game. Each strategy has strengths that allow it to outcompete one morph, and weaknesses that leave it vulnerable to the strategy of another. Blue-throated males mate-guard their females and avoid cuckoldry by yellow-throated “sneaker” males, but mate-guarding is ineffective against aggressive orange-throated neighbors. The ultradominant orange-throated males are highly polygynous and maintain large territories; they overpower blue-throated neighbors and cosire offspring with their females, but are often cuckolded by yellow-throated males. Finally, yellow-throated sneaker males sire offspring via secretive copulations and often share paternity of offspring within a female's clutch. Sneaker males sire more offspring posthumously, indicating that sperm competition may be an important component of their strategy. PMID:11106369

  7. Selection by mating competitiveness improves the performance of Anastrepha ludens males of the genetic sexing strain Tapachula-7.

    PubMed

    Quintero-Fong, L; Toledo, J; Ruiz, L; Rendón, P; Orozco-Dávila, D; Cruz, L; Liedo, P

    2016-10-01

    The sexual performance of Anastrepha ludens males of the Tapachula-7 genetic sexing strain, produced via selection based on mating success, was compared with that of males produced without selection in competition with wild males. Mating competition, development time, survival, mass-rearing quality parameters and pheromone production were compared. The results showed that selection based on mating competitiveness significantly improved the sexual performance of offspring. Development time, survival of larvae, pupae and adults, and weights of larvae and pupae increased with each selection cycle. Differences in the relative quantity of the pheromone compounds (Z)-3-nonenol and anastrephin were observed when comparing the parental males with the F4 and wild males. The implications of this colony management method on the sterile insect technique are discussed.

  8. Comparative Transcriptome Analysis of Recessive Male Sterility (RGMS) in Sterile and Fertile Brassica napus Lines

    PubMed Central

    Zhao, Huiyan; Liu, Chuan; Li, Jiana; Tang, Zhanglin; Xu, Xinfu; Qiu, Xiao; Wang, Rui; Lu, Kun

    2015-01-01

    The recessive genetic male sterility (RGMS) system plays a key role in the production of hybrid varieties in self-pollinating B. napus plants, and prevents negative cytoplasmic effects. However, the complete molecular mechanism of the male sterility during male-gametogenesis in RGMS remains to be determined. To identify transcriptomic changes that occur during the transition to male sterility in RGMS, we examined the male sterile line WSLA and male fertile line WSLB, which are near-isogenic lines (NILs) differing only in the fertility trait. We evaluated the phenotypic features and sterility stage using anatomical analysis. Comparative RNA sequencing analysis revealed that 3,199 genes were differentially expressed between WSLA and WSLB. Many of these genes are mainly involved in biological processes related to flowering, including pollen tube development and growth, pollen wall assembly and modification, and pollen exine formation and pollination. The transcript profiles of 93 genes associated with pollen wall and anther development were determined by quantitative RT-PCR in different flower parts, and classified into the following three major clades: 1) up-regulated in WSLA plants; 2) down-regulated in WSLA plants; and 3) down-regulated in buds, but have a higher expression in stigmas of WSLA than in WSLB. A subset of genes associated with sporopollenin accumulation were all up-regulated in WSLA. An excess of sporopollenin results in defective pollen wall formation, which leads to male sterility in WSLA. Some of the genes identified in this study are candidates for future research, as they could provide important insight into the molecular mechanisms underlying RGMS in WSLA. PMID:26656530

  9. Sugar administration to newly emerged Aedes albopictus males increases their survival probability and mating performance.

    PubMed

    Bellini, Romeo; Puggioli, Arianna; Balestrino, Fabrizio; Brunelli, Paolo; Medici, Anna; Urbanelli, Sandra; Carrieri, Marco

    2014-04-01

    capacity of sterile (irradiated with 30 Gy) males to take a sugar meal relative to fertile males was observed in field comparison. A clear effect of temperature and relative humidity (RH) on the rate of sugar positive males was observed, with an increase of temperature and a decrease in RH strongly increasing the % of sugar positive males. In large enclosures we tested the effect of our sugar supplying tool on the mating competitiveness of sterile vs fertile males, which produced an evident favorable effect both on sterile and fertile males.

  10. The impact of social context on male mate preference in a unisexual--bisexual mating complex.

    PubMed

    Alberici da Barbiano, L; Aspbury, A S; Nice, C C; Gabor, C R

    2011-07-01

    Male sailfin mollies Poecilia latipinna were tested in five different treatments that varied in the relative frequency of heterospecific gynogens (Amazon molly Poecilia formosa) to conspecific females to determine whether social interactions among males within a population causes some males to mate with heterospecific females. Male P. latipinna inseminated a significantly higher proportion of conspecific females and fertilized a significantly higher number of conspecific eggs regardless of the treatment. Nonetheless, preference for conspecific females was not exclusive as a range of 20 to 50% of heterospecific females were fertilized. Social interactions among males may best explain the results and may therefore play an important role in the maintenance of unisexual--bisexual mating complexes.

  11. Male-male and male-female aggression may influence mating associations in wild octopuses (Abdopus aculeatus).

    PubMed

    Huffard, Christine L; Caldwell, Roy L; Boneka, Farnis

    2010-02-01

    Abdopus aculeatus engages in frequent aggression and copulation, exhibits male mate-choice, and employs multiple mating tactics. Here we draw upon established hypotheses to compare male-male aggression (MMA) and male-female aggression (MFA), as they relate to their mating behavior in the wild. When contesting for females, males appear to balance mate preference (resource value) with perceived chances of winning contests (resource holding potential). Although males spent more time mating with and contesting for large "Adjacent Guarded" females (those occupying a den within arm's reach of a large "Adjacent Guarding" male), they exhibited higher rates of aggression over nonadjacent "Temporarily Guarded" females that may be more accessible. The major determinant of male-male aggressive success was size, and this factor may dictate the expression of conditional mating tactics in males. "Adjacent Guarding" males were the largest and most aggressively successful males, earning the most time copulating with females. They are considered to have the highest resource holding potential (RHP) in MMA. By contrast, in MFA, some larger individuals fled from smaller individuals, indicating that RHP appears to be a function of both size and sex in intersexual aggression. This result suggests variation in aggressiveness, or potential for severe injury-even sexual cannibalism during MFA. Male-female aggression may also be influenced by the sexual nonreceptivity of some individuals, or attempts by both sexes to increase foraging behavior by delaying mate-guarding activity.

  12. The role of meiotic drive in hybrid male sterility

    PubMed Central

    McDermott, Shannon R.; Noor, Mohamed A. F.

    2010-01-01

    Meiotic drive causes the distortion of allelic segregation away from Mendelian expected ratios, often also reducing fecundity and favouring the evolution of drive suppressors. If different species evolve distinct drive-suppressor systems, then hybrid progeny may be sterile as a result of negative interactions of these systems' components. Although the hypothesis that meiotic drive may contribute to hybrid sterility, and thus species formation, fell out of favour early in the 1990s, recent results showing an association between drive and sterility have resurrected this previously controversial idea. Here, we review the different forms of meiotic drive and their possible roles in speciation. We discuss the recent empirical evidence for a link between drive and hybrid male sterility, also suggesting a possible mechanistic explanation for this link in the context of chromatin remodelling. Finally, we revisit the population genetics of drive that allow it to contribute to speciation. PMID:20308102

  13. Evaluation of sterility and fertility of male sterile lines in the USPB farm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hybrid rice has proven to have a yield advantage of 15–20% over the best inbred cultivars at the commercial scale worldwide. At present, two methods have been successfully commercialized; the three-line and two-line systems. The three-line system consists of the male sterile (MS), maintainer and res...

  14. Do male breeding displays function to attract mates or defend territories? The explanatory role of mate and site fidelity

    USGS Publications Warehouse

    Lanctot, Richard B.; Sandercock, B.K.; Kempenaers, Bart

    2000-01-01

    Many shorebirds show elaborate breeding displays that include aerial flights and ground displays accompanied by song. The mate attraction hypothesis suggests that breeding displays function to attract mates and maintain pair bonds, whereas the territory defense hypothesis suggests breeding displays function in defining and defending nesting and feeding territories. We tested these hypotheses in the Western Sandpiper (Calidris mauri) by contrasting the duration and level of male breeding displays among pairs that differed in their mate and site fidelity. As predicted by the mate attraction hypothesis, males performed the highest number of song sequences during pair formation, and males paired with their mate of a prior year sang less than males paired to new mates. Further, sitefaithful males mated to a new but experienced mate displayed significantly more than remated males or males new to the area. This suggests a male's prior familiarity with an area and his neighbors does not lessen his display rate as was predicted under the territory defense hypothesis. Limited support for the territory defense hypothesis came from observations of males performing breeding displays with neighboring males along nest territory boundaries. This behavior was short-lived, however, as males abandoned nesting areas after pair-formation and used adjacent or disjointed feeding areas during egg-laying and incubation. Male aggression (i.e., aerial and ground chases), as opposed to breeding displays, appeared to be the principal means of maintaining territory boundaries. Indeed, the rate at which males chased other males remained fairly constant and high throughout the breeding season. Male chasing behavior may also serve as a paternity guard to protect against extra-pair copulations. Our study also found that a female's prior breeding experience in an area correlated with a reduced display rate by her mate, particularly if that mate was new to the area. This indicates female

  15. Genetics and evolution of hybrid male sterility in house mice.

    PubMed

    White, Michael A; Stubbings, Maria; Dumont, Beth L; Payseur, Bret A

    2012-07-01

    Comparative genetic mapping provides insights into the evolution of the reproductive barriers that separate closely related species. This approach has been used to document the accumulation of reproductive incompatibilities over time, but has only been applied to a few taxa. House mice offer a powerful system to reconstruct the evolution of reproductive isolation between multiple subspecies pairs. However, studies of the primary reproductive barrier in house mice-hybrid male sterility-have been restricted to a single subspecies pair: Mus musculus musculus and Mus musculus domesticus. To provide a more complete characterization of reproductive isolation in house mice, we conducted an F(2) intercross between wild-derived inbred strains from Mus musculus castaneus and M. m. domesticus. We identified autosomal and X-linked QTL associated with a range of hybrid male sterility phenotypes, including testis weight, sperm density, and sperm morphology. The pseudoautosomal region (PAR) was strongly associated with hybrid sterility phenotypes when heterozygous. We compared QTL found in this cross with QTL identified in a previous F(2) intercross between M. m. musculus and M. m. domesticus and found three shared autosomal QTL. Most QTL were not shared, demonstrating that the genetic basis of hybrid male sterility largely differs between these closely related subspecies pairs. These results lay the groundwork for identifying genes responsible for the early stages of speciation in house mice.

  16. Temporal variation in size-assortative mating and male mate choice in a spider with amphisexual care.

    PubMed

    Moura, Rafael R; Gonzaga, Marcelo O

    2017-04-01

    Males should be more selective when they have a high investment in reproduction, especially in species with biparental or paternal care. In this context, male mate choice can promote size-assortative mating (SAM) when (1) large males win intrasexual disputes, (2) large females are more fecund, and (3) males prefer larger females to smaller ones. In the spider Manogea porracea, males exhibit high reproductive investment by building their webs above those of females and exhibiting extended care of offspring in the absence of females. Under these circumstances, we expect the occurrence of SAM and male preference for large females. Herein, we performed observations and experiments in the field to evaluate the hypotheses that (1) M. porracea mates assortatively by size and (2) SAM is influenced by male mate choice. Furthermore, we measured variables that could affect mating patterns, the sex ratios, and densities of both sexes. Pairing in M. porracea was positively size-assortative in 2012, but not in 2013. Large males won most disputes for mates and preferred larger females, which produced more eggs. The inconsistency in detection of SAM was due to population dynamics, namely variations in sex ratio and population density across the breeding season. Furthermore, we found that the significance of male mate choice on sexual selection of body size in M. porracea strongly depends on the competition intensity for mating opportunities. The traditional sexual selection hypothesis of SAM needs to be reviewed and must include measures of competition intensity.

  17. Temporal variation in size-assortative mating and male mate choice in a spider with amphisexual care

    NASA Astrophysics Data System (ADS)

    Moura, Rafael R.; Gonzaga, Marcelo O.

    2017-04-01

    Males should be more selective when they have a high investment in reproduction, especially in species with biparental or paternal care. In this context, male mate choice can promote size-assortative mating (SAM) when (1) large males win intrasexual disputes, (2) large females are more fecund, and (3) males prefer larger females to smaller ones. In the spider Manogea porracea, males exhibit high reproductive investment by building their webs above those of females and exhibiting extended care of offspring in the absence of females. Under these circumstances, we expect the occurrence of SAM and male preference for large females. Herein, we performed observations and experiments in the field to evaluate the hypotheses that (1) M. porracea mates assortatively by size and (2) SAM is influenced by male mate choice. Furthermore, we measured variables that could affect mating patterns, the sex ratios, and densities of both sexes. Pairing in M. porracea was positively size-assortative in 2012, but not in 2013. Large males won most disputes for mates and preferred larger females, which produced more eggs. The inconsistency in detection of SAM was due to population dynamics, namely variations in sex ratio and population density across the breeding season. Furthermore, we found that the significance of male mate choice on sexual selection of body size in M. porracea strongly depends on the competition intensity for mating opportunities. The traditional sexual selection hypothesis of SAM needs to be reviewed and must include measures of competition intensity.

  18. [Calcium distribution in fertile and sterile anthers of a genic male sterile Chinese cabbage].

    PubMed

    Xie, Chao-Tian; Yang, Yan-Hong; Qiu, Yi-Lan; Ge, Li-Li; Tian, Hui-Qiao

    2005-12-01

    Potassium antimonite was used to locate calcium in the fertile and sterile anthers of a genic male sterile Chinese cabbage (Brassica campestris L. ssp. chinensis Makino) to probe the relation between Ca(2+) and fertility and sterility of anthers of the cabbage. During fertile anther development, calcium granules increase in number in anther wall cells after meiosis, and then appeared also in locule, suggesting a calcium influx into locule from anther wall cells (Plate I-4). Then the number of calcium granules in microspore cytoplasm also increased at early stage (Plate II-1), accumulated mainly on the membrane of small vacuoles which were fusing to form big ones to make a polarity in the cell and to prepare asymmetric division of microspore (Plate II-3,4). After microspore division and the big vacuole decomposition, many calcium granules accumulated again on the membrane of the vacuoles (Plate III-1,2), displaying calcium regulates vacuole formation and decomposition during pollen development. In sterile anthers, abnormal distribution of calcium granules first appeared in callus wall of microspore mother cell (Plate IV-1). However, only a few calcium granules appeared in early microspores, which then could not form small vacuoles and finally a big vacuole (Plate IV-2,3). The aborting microspores degenerate by cytoplasm shrinking (Plate IV-5,6). The difference pattern of distribution of calcium granules between the fertile and sterile anthers indicates that anomalies in the distribution of calcium accumulation are correlated with the failure of pollen development and pollen abortion.

  19. Assortative mating and differential male mating success in an ash hybrid zone population

    PubMed Central

    Gérard, Pierre R; Klein, Etienne K; Austerlitz, Frédéric; Fernández-Manjarrés, Juan F; Frascaria-Lacoste, Nathalie

    2006-01-01

    Background The structure and evolution of hybrid zones depend mainly on the relative importance of dispersal and local adaptation, and on the strength of assortative mating. Here, we study the influence of dispersal, temporal isolation, variability in phenotypic traits and parasite attacks on the male mating success of two parental species and hybrids by real-time pollen flow analysis. We focus on a hybrid zone population between the two closely related ash species Fraxinus excelsior L. (common ash) and F. angustifolia Vahl (narrow-leaved ash), which is composed of individuals of the two species and several hybrid types. This population is structured by flowering time: the F. excelsior individuals flower later than the F. angustifolia individuals, and the hybrid types flower in-between. Hybrids are scattered throughout the population, suggesting favorable conditions for their local adaptation. We estimate jointly the best-fitting dispersal kernel, the differences in male fecundity due to variation in phenotypic traits and level of parasite attack, and the strength of assortative mating due to differences in flowering phenology. In addition, we assess the effect of accounting for genotyping error on these estimations. Results We detected a very high pollen immigration rate and a fat-tailed dispersal kernel, counter-balanced by slight phenological assortative mating and short-distance pollen dispersal. Early intermediate flowering hybrids, which had the highest male mating success, showed optimal sex allocation and increased selfing rates. We detected asymmetry of gene flow, with early flowering trees participating more as pollen donors than late flowering trees. Conclusion This study provides striking evidence that long-distance gene flow alone is not sufficient to counter-act the effects of assortative mating and selfing. Phenological assortative mating and short-distance dispersal can create temporal and spatial structuring that appears to maintain this hybrid

  20. Progress in development of male sterile germplasm for hybrid rice breeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Currently, there are two types of male sterility mainly commercialized in hybrid rice production, three-line type or cytoplasmic male sterility (CMS) and two-line type or environmental male sterility (EMS). The great majority belongs to the CMS and there are four strategies that have been proven suc...

  1. Genetics and Evolution of Hybrid Male Sterility in House Mice

    PubMed Central

    White, Michael A.; Stubbings, Maria; Dumont, Beth L.; Payseur, Bret A.

    2012-01-01

    Comparative genetic mapping provides insights into the evolution of the reproductive barriers that separate closely related species. This approach has been used to document the accumulation of reproductive incompatibilities over time, but has only been applied to a few taxa. House mice offer a powerful system to reconstruct the evolution of reproductive isolation between multiple subspecies pairs. However, studies of the primary reproductive barrier in house mice—hybrid male sterility—have been restricted to a single subspecies pair: Mus musculus musculus and Mus musculus domesticus. To provide a more complete characterization of reproductive isolation in house mice, we conducted an F2 intercross between wild-derived inbred strains from Mus musculus castaneus and M. m. domesticus. We identified autosomal and X-linked QTL associated with a range of hybrid male sterility phenotypes, including testis weight, sperm density, and sperm morphology. The pseudoautosomal region (PAR) was strongly associated with hybrid sterility phenotypes when heterozygous. We compared QTL found in this cross with QTL identified in a previous F2 intercross between M. m. musculus and M. m. domesticus and found three shared autosomal QTL. Most QTL were not shared, demonstrating that the genetic basis of hybrid male sterility largely differs between these closely related subspecies pairs. These results lay the groundwork for identifying genes responsible for the early stages of speciation in house mice. PMID:22554891

  2. Female mate choice across spatial scales: influence of lek and male attributes on mating success of blue-crowned manakins.

    PubMed

    Durães, Renata; Loiselle, Bette A; Parker, Patricia G; Blake, John G

    2009-05-22

    Lekking males compete for females within and among leks, yet female choice is expected to work differently at each of these spatial scales. We used paternity analyses to examine how lek versus male attributes influence mate choice in the blue-crowned manakin Lepidothrix coronata. We tested the hypotheses that females prefer (i) to mate at larger leks where a larger number of potential mates can be assessed, (ii) to mate with unrelated or highly heterozygous males expected to produce high-quality offspring, (iii) to mate with males that display at higher rates, and that (iv) display honestly reflects male genetic quality. Our results show that (i) males at larger leks are not more likely to sire young, although females nesting close to small leks travel further to reach larger leks, (ii) siring males are not less related to females or more heterozygous than expected, (iii) within a lek, high-display males are more likely to sire young, and (iv) both male heterozygosity and display rate increased with lek size, and as a result display does not reliably reflect male genetic quality across leks. We suggest that female mate choice in this species is probably driven by a Fisherian process rather than adaptive genetic benefits.

  3. The effect of the radio-protective agents ethanol, trimethylglycine, and beer on survival of X-ray-sterilized male Aedes aegypti

    PubMed Central

    2013-01-01

    Background Sterile Insect Technique (SIT) has been successfully implemented to control, and in some cases, eradicate, dipteran insect populations. SIT has great potential as a mosquito control method. Different sterilization methods have been used on mosquitoes ranging from chemosterilization to genetically modified sterile male mosquito strains; however, sterilization with ionizing radiation is the method of choice for effective sterilization of male insects for most species. The lack of gentle radiation methods has resulted in significant complications when SIT has been applied to mosquitoes. Several studies report that irradiating mosquitoes resulted in a decrease in longevity and mating success compared to unirradiated males. The present study explored new protocols for mosquito sterilization with ionizing radiation that minimized detrimental effects on the longevity of irradiated males. Methods We tested three compounds that have been shown to act as radioprotectors in the mouse model system - ethanol, trimethylglycine, and beer. Male Aedes aegypti were treated with one of three chosen potential radioprotectors and were subsequently irradiated with identical doses of long-wavelength X-rays. We evaluated the effect of these radioprotectors on the longevity of male mosquito after irradiation. Results We found that X-ray irradiation with an absorbed dose of 1.17 gy confers complete sterility. Irradiation with this dose significantly shortened the lifespan of male mosquitoes and all three radioprotectors tested significantly enhanced the lifespan of irradiated mosquito males. Conclusion Our results suggest that treatment with ethanol, beer, or trimethylglycine before irradiation can be used to enhance longevity in mosquitoes. PMID:23866939

  4. Mating with large males decreases the immune defence of females in Drosophila melanogaster.

    PubMed

    Imroze, K; Prasad, N G

    2011-12-01

    Mating has been widely reported to be a costly event for females. Studies indicate that female cost of mating in terms of fecundity and survivorship can be affected by their mates, leading to antagonistic coevolution between the sexes. However, as of now, there is no evidence that the female cost of mating in terms of immune defence is affected by their mates. We assess the effect of different sized males on antibacterial immune defence and reproductive fitness of their mates. We used a large outbred population of Drososphila melanogaster as the host and Serratia marcescens as the pathogen. We generated three different male phenotypes: small, medium and large, by manipulating larval densities. Compared to females mating with small males, those mating with large males had higher bacterial loads and lower fecundity. There was no significant effect of male phenotype on the fraction of females mated or copulation duration (an indicator of ejaculate investment). Thus, our study is the first clear demonstration that male phenotype can affect the cost of mating to females in terms of their antibacterial immune defence. Mating with large males imposes an additional cost of mating to females in terms of reduced immune defence. The observed results are very likely due to qualitative/quantitative differences in the ejaculates of the three different types of males. If the phenotypic variation that we observed in males in our study is mirrored by genetic variation, then, it can potentially lead to antagonistic coevolution of the sexes over immune defence.

  5. Caenorhabditis elegans glutamylating enzymes function redundantly in male mating

    PubMed Central

    Chawla, Daniel G.; Shah, Ruchi V.; Barth, Zachary K.; Lee, Jessica D.; Badecker, Katherine E.; Naik, Anar; Brewster, Megan M.; Salmon, Timothy P.

    2016-01-01

    ABSTRACT Microtubule glutamylation is an important modulator of microtubule function and has been implicated in the regulation of centriole stability, neuronal outgrowth and cilia motility. Glutamylation of the microtubules is catalyzed by a family of tubulin tyrosine ligase-like (TTLL) enzymes. Analysis of individual TTLL enzymes has led to an understanding of their specific functions, but how activities of the TTLL enzymes are coordinated to spatially and temporally regulate glutamylation remains relatively unexplored. We have undertaken an analysis of the glutamylating TTLL enzymes in C. elegans. We find that although all five TTLL enzymes are expressed in the embryo and adult worm, loss of individual enzymes does not perturb microtubule function in embryonic cell divisions. Moreover, normal dye-filling, osmotic avoidance and male mating behavior indicate the presence of functional amphid cilia and male-specific neurons. A ttll-4(tm3310); ttll-11(tm4059); ttll-5(tm3360) triple mutant, however, shows reduced male mating efficiency due to a defect in the response step, suggesting that these three enzymes function redundantly, and that glutamylation is required for proper function of the male-specific neurons. PMID:27635036

  6. The best time to have sex: mating behaviour and effect of daylight time on male sexual competitiveness in the Asian tiger mosquito, Aedes albopictus (Diptera: Culicidae).

    PubMed

    Benelli, Giovanni

    2015-03-01

    Aedes albopictus is the most invasive mosquito worldwide and works as a vector for many important pathogens. Control tools rely to chemical treatments against larvae, indoor residual spraying and insecticide-treated bed nets. Recently, huge efforts have been carried out to propose new eco-friendly alternatives, such as evaluation of plant-borne compounds and sterile insect technique (SIT) programs. Success of SIT is dependent to the ability of sterile males to compete for mates with wild ones. Little is still known about mating behaviour of Aedes males. Most of the studies focus on comparisons of insemination ability in sterilised and wild males, while behavioural analyses of mating behaviour are lacking. Here, I quantified the courtship and mating behaviour of A. albopictus and evaluated how daylight hours affect male mating behaviour and success. A. albopictus males chased females facing them frontally, from behind, or from a lateral side. If the female allowed genital contact, copulation followed. Otherwise, females performed rejection kicks and/or flew away. Thirty-seven percent of males obtained a successful copulation (i.e. sperm transfer occurs), lasting 63 ± 4 s. Unsuccessful copulation (20 % of males) had shorter duration (18 ± 1 s). Successful copulations followed longer male courtships (39 ± 3 s), over courtships preceding unsuccessful copulation (20 ± 2 s) or male's rejection (22 ± 2 s). After copulation, the male rested 7 ± 0.4 s close to the female, then move off. In a semi-natural environment, male mating success was lower in early afternoon, over morning and late afternoon. However, little differences in courtship duration over daylight periods were found. This study adds knowledge to the reproductive behaviour of A. albopictus, which can be used to perform comparisons among courtship and mating ethograms from different mosquito species and strains, allowing monitoring and optimisation of mass rearing quality over time in SIT programs.

  7. The evolution of wing color: male mate choice opposes adaptive wing color divergence in Colias butterflies.

    PubMed

    Ellers, Jacintha; Boggs, Carol L

    2003-05-01

    Correlated evolution of mate signals and mate preference may be constrained if selection pressures acting on mate preference differ from those acting on mate signals. In particular, opposing selection pressures may act on mate preference and signals when traits have sexual as well as nonsexual functions. In the butterfly Colias philodice eriphyle, divergent selection on wing color across an elevational gradient in response to the thermal environment has led to increasing wing melanization at higher elevations. Wing color is also a long-range signal used by males in mate searching. We conducted experiments to test whether sexual selection on wing melanization via male mate choice acts in the same direction as natural selection on mate signals due to the thermal environment. We performed controlled mate choice experiments in the field over an elevational range of 1500 meters using decoy butterflies with different melanization levels. Also, we obtained a more direct estimate of the relation between wing color and sexual selection by measuring mating success in wild-caught females. Both our experiments showed that wing melanization is an important determinant of female mating success in C. p. eriphyle. However, a lack of elevational variation in male mate preference prevents coevolution of mate signals and mate preference, as males at all elevations prefer less-melanized females. We suggest that this apparently maladaptive mate choice may be maintained by differences in detectability between the morphs or by preservation of species recognition.

  8. Mitochondrion role in molecular basis of cytoplasmic male sterility.

    PubMed

    Horn, Renate; Gupta, Kapuganti J; Colombo, Noemi

    2014-11-01

    Cytoplasmic male sterility and its fertility restoration via nuclear genes offer the possibility to understand the role of mitochondria during microsporogenesis. In most cases rearrangements in the mitochondrial DNA involving known mitochondrial genes as well as unknown sequences result in the creation of new chimeric open reading frames, which encode proteins containing transmembrane domains. So far, most of the CMS systems have been characterized via restriction fragment polymorphisms followed by transcript analysis. However, whole mitochondrial genome sequence analyses comparing male sterile and fertile cytoplasm open options for deeper insights into mitochondrial genome rearrangements. We more and more start to unravel how mitochondria are involved in triggering death of the male reproductive organs. Reduced levels of ATP accompanied by increased concentrations of reactive oxygen species, which are produced more under conditions of mitochondrial dysfunction, seem to play a major role in the fate of pollen production. Nuclear genes, so called restorer-of-fertility are able to restore the male fertility. Fertility restoration can occur via pentatricopeptide repeat (PPR) proteins or via different mechanisms involving non-PPR proteins.

  9. Expression of Engineered Nuclear Male Sterility in Brassica napus (Genetics, Morphology, Cytology, and Sensitivity to Temperature).

    PubMed Central

    Denis, M.; Delourme, R.; Gourret, J. P.; Mariani, C.; Renard, M.

    1993-01-01

    A dominant genetic male sterility trait obtained through transformation in rapeseed (Brassica napus) was studied in the progenies of 11 transformed plants. The gene conferring the male sterility consists of a ribonuclease gene under the control of a tapetum-specific promoter. Two ribonuclease genes, RNase T1 and barnase, were used. The chimaeric ribonuclease gene was linked to the bialophos-resistance gene, which confers resistance to the herbicide phosphinotricine (PPT). The resistance to the herbicide was used as a dominant marker for the male sterility trait. The study presented here concerns three aspects of this engineered male sterility: genetics correlated with the segregation of the T-DNA in the progenies; expression of the male sterility in relation to the morphology and cytology of the androecium; and stability of the engineered male sterility under different culture conditions. Correct segregation, 50% male-sterile, PPT-resistant plants, and 50% male-fertile, susceptible plants were observed in the progeny of seven transformants. The most prominent morphological change in the male-sterile flowers was a noticeable reduction in the length of the stamen filament. The first disturbances of microsporogenesis were observed from the free microspore stage and were followed by a simultaneous degeneration of microspore and tapetal cell content. At anthesis, the sterile anthers contained only empty exines. In some cases, reversion to fertility of male-sterile plants has been observed. Both ribonuclease genes are susceptible to instability. Instability of the RNase T1-male sterility trait increased at temperatures higher than 25[deg] C. Our results do not allow us to confirm this observation for the barnase male-sterile plants. However, the male-sterile plants of the progeny of two independent RNase T1 transformants were stably male sterile under all conditions studied. PMID:12231785

  10. Cost of reproduction in Callosobruchus maculatus: effects of mating on male longevity and the effect of male mating status on female longevity.

    PubMed

    Paukku, Satu; Kotiaho, Janne S

    2005-11-01

    One of the most studied life-history trade-offs is that resulting from the cost of reproduction: a trade-off arises when reproduction diverts limited resources from other life-history traits. We examine the cost of reproduction in male, and the effect of male mating status on female Callosobruchus maculatus seed beetles. Cost of reproduction for male C. maculatus was manifested as reduced longevity. There was also a positive relationship between male body size and male longevity. Females mated to males that had already copulated twice did not live as long as females mated to males that had copulated once or not at all. The third copulation of males also lasted longer than the two previous ones. We conclude that even though the cost of reproduction for males has been studied much less than that in females, there is growing evidence that male reproductive effort is more complex than has traditionally been thought.

  11. The evolution of male mate choice in insects: a synthesis of ideas and evidence.

    PubMed

    Bonduriansky, R

    2001-08-01

    Mate choice by males has been recognized at least since Darwin's time, but its phylogenetic distribution and effect on the evolution of female phenotypes remain poorly known. Moreover, the relative importance of factors thought to underlie the evolution of male mate choice (especially parental investment and mate quality variance) is still unresolved. Here I synthesize the empirical evidence and theory pertaining to the evolution of male mate choice and sex role reversal in insects, and examine the potential for male mating preferences to generate sexual selection on female phenotypes. Although male mate choice has received relatively little empirical study, the available evidence suggests that it is widespread among insects (and other animals). In addition to 'precopulatory' male mate choice, some insects exhibit 'cryptic' male mate choice, varying the amount of resources allocated to mating on the basis of female mate quality. As predicted by theory, the most commonly observed male mating preferences are those that tend to maximize a male's expected fertilization success from each mating. Such preferences tend to favour female phenotypes associated with high fecundity or reduced sperm competition intensity. Among insect species there is wide variation in mechanisms used by males to assess female mate quality, some of which (e.g. probing, antennating or repeatedly mounting the female) may be difficult to distinguish from copulatory courtship. According to theory, selection for male choosiness is an increasing function of mate quality variance and those reproductive costs that reduce, with each mating, the number of subsequent matings that a male can perform ('mating investment') Conversely, choosiness is constrained by the costs of mate search and assessment, in combination with the accuracy of assessment of potential mates and of the distribution of mate qualities. Stronger selection for male choosiness may also be expected in systems where female fitness

  12. Mating behavior of adolescent male chimpanzees (Pan troglodytes) at Ngogo, Kibale National Park, Uganda.

    PubMed

    Watts, David P

    2015-04-01

    Male mating tactics vary extensively in many primates. Some variation occurs because adolescent males often are sexually active but cannot invest heavily in mating effort because of their limited ability to compete directly with adults and because they are still investing in growth; consequently, most of their mating attempts may be surreptitious and/or with females whose fecundity is low. Chimpanzees (Pan troglodytes) have a complex mating system: most copulations occur between estrous females with full sexual swelling and multiple males in group settings where the potential for sperm competition is high, but males sometimes mate-guard females, and sometimes male-female pairs mate exclusively with each other while avoiding other males during "consortships." Among other factors, dominance ranks, coalition formation, and variation in male-female association influence male mating and reproductive success. Mating effort increases from adolescence into prime adulthood. At Gombe and Mahale, adolescent males copulated more with nulliparous than with parous females, and mostly when females were unlikely to be ovulating, partly because of low adult male interest in nulliparous females and partly because of aggression from or avoidance of adult males. Adolescents thus had low probabilities of siring infants. However, adolescents are known to have gained some paternity at Gombe and in other populations, and their mating behavior deserves more study. I present data on mating by adolescent males in an unusually large chimpanzee community at Ngogo, Kibale National Park, Uganda. Adolescents at Ngogo also copulated more with nulliparous than parous females and mostly copulated outside of periovulatory periods. Also, they directed less aggression at estrous females than did adult males. However, they gained lower shares of copulations than reported for Gombe and Mahale, regardless of female parity, and received more aggression from adult males. These differences might partly

  13. Genetic studies on cytoplasmic male sterility in maize

    SciTech Connect

    Laughnan, J.R.

    1992-01-01

    Our research concerns the basic mechanisms of cytoplasmic male sterility (CMS) and fertility restoration in maize. The molecular determination of CMS is in the DNA of the mitochondria (mtDNA) but specific nuclear restorer-of-fertility (Rf) genes can overrule the male-sterile effect of the cytoplasm. Our approach to the study of the Rf genes is threefold. We are attempting to tag the cms-S Rf genes and the cms-T Rf2 gene with controlling elements (CEs). Since we have identified a number of spontaneous Rf genes for cms-S and have demonstrated that they are themselves transposable, we are also searching for cases in which an Rf gene is inserted into a wild-type gene. The other aspect of our research involves the nuclear control over the organization of the mitochondrial genome. We found that the changes in mtDNA organization upon cytoplasmic reversion to fertility were characteristic of the nuclear background in which the reversion event occurred. We have investigated whether these differences are a reflection of differences in the organization of the mtDNA genome before reversion.

  14. Improving mating performance of mass-reared sterile Mediterranean fruit flies (Diptera: Tephritidae) through changes in adult holding conditions: demography and mating competitiveness

    SciTech Connect

    Liedo, P.; Salgado, S.; Oropeza, A.; Toledo, J.

    2007-03-15

    with wild flies. As colonization progressed, life expectancy and fecundity rates increased in the 3 rearing systems. There was no significant difference in standard quality control parameters among the 3 rearing systems. Wild males always achieved more matings than any of the mass reared males. Mating competitiveness of males from the IS, although surprisingly not from the SS, was significantly greater than that of males from the MS. Our results indicate that these slight changes in the adult holding conditions can significantly reduce the harmful effects of mass rearing on the mating performance of sterile flies. (author) [Spanish] Se ha demostrado que las condiciones de cria masiva afectan el comportamiento de apareamiento de la mosca del Mediterraneo Ceratitis capitata (Wiedemann). Nosotros evaluamos el efecto de ligeros cambios en las condiciones en las que los adultos son mantenidos para la produccion de huevos, en el desempeno de apareamiento de las moscas esteriles. La colonizacion se inicio con moscas silvestres colectadas como larvas en cerezas de cafe (Coffea arabica L.) infestadas. Cuando las pupas estuvieron cerca de la emergencia de los adultos, se dividieron en tres grupos al azar y los adultos recien emergidos fueron criados en las siguientes condiciones: (1) Sistema Metapa (MS, testigo), consistente en jaulas con marco de aluminio de 70 x 45 x 15 cm, cubiertas con malla, con una densidad de 2,200 moscas por jaula y una relacion de sexos inicial de 1:1; (2); Sistema Insertos (IS), con el mismo tipo de jaula, densidad de moscas, y relacion de sexos que en el MS, pero conteniendo 12 piezas de plexiglas (23 x 8.5 cm) para proporcionar superficie horizontal al interior de la jaula; y (3) Sistema de Relacion de Sexos (SS), igual que el IS, pero en este caso la relacion inicial macho: hembra fue de 4:1, tres dias despues se introdujeron hembras recien emergidas para tener una relacion de 3:1 y en el 6 dia se anadio otro grupo de hembras para tener una relacion

  15. The dance of male Anopheles gambiae in wild mating swarms.

    PubMed

    Butail, Sachit; Manoukis, Nicholas C; Diallo, Moussa; Ribeiro, José M C; Paley, Derek A

    2013-05-01

    An important element of mating in the malaria vector Anopheles gambiae Giles in nature is the crepuscular mating aggregation (swarm) composed almost entirely of males, where most coupling and insemination is generally believed to occur. In this study, we mathematically characterize the oscillatory movement of male An. gambiae in terms of an established individual-based mechanistic model that parameterizes the attraction of a mosquito toward the center of the swarm using the natural frequency of oscillation and the resistance to its motion, characterized by the damping ratio. Using three-dimensional trajectory data of ten wild mosquito swarms filmed in Mali, Africa, we show two new results for low and moderate wind conditions, and indicate how these results may vary in high wind. First, we show that in low and moderate wind the vertical component of the mosquito motion has a lower frequency of oscillation and higher damping ratio than horizontal motion. In high wind, the vertical and horizontal motions are similar to one another and the natural frequencies are higher than in low and moderate wind. Second, we show that the predicted average disagreement in the direction of motion of swarming mosquitoes moving randomly is greater than the average disagreement we observed between each mosquito and its three closest neighbors, with the smallest level of disagreement occurring for the nearest neighbor in seven out of 10 swarms. The alignment of the direction of motion between nearest neighbors is the highest in high wind. This result provides evidence for flight-path coordination between swarming male mosquitoes.

  16. Male lifetime mating success in relation to body size in Diabrotica barberi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Body size is often an important component of male lifetime mating success in insects, especially when males are capable of mating several times over their lifespan. We paired either a large or small male northern corn rootworm with a female of random size and noted copulation success. We observed co...

  17. Female Choice or Male Sex Drive? The Advantages of Male Body Size during Mating in Drosophila Melanogaster.

    PubMed

    Jagadeeshan, Santosh; Shah, Ushma; Chakrabarti, Debarti; Singh, Rama S

    2015-01-01

    The mating success of larger male Drosophila melanogaster in the laboratory and the wild has been traditionally been explained by female choice, even though the reasons are generally hard to reconcile. Female choice can explain this success by virtue of females taking less time to mate with preferred males, but so can the more aggressive or persistent courtships efforts of large males. Since mating is a negotiation between the two sexes, the behaviors of both are likely to interact and influence mating outcomes. Using a series of assays, we explored these negotiations by testing for the relative influence of male behaviors and its effect on influencing female courtship arousal threshold, which is the time taken for females to accept copulation. Our results show that large males indeed have higher copulation success compared to smaller males. Competition between two males or an increasing number of males had no influence on female sexual arousal threshold;-females therefore may have a relatively fixed 'arousal threshold' that must be reached before they are ready to mate, and larger males appear to be able to manipulate this threshold sooner. On the other hand, the females' physiological and behavioral state drastically influences mating; once females have crossed the courtship arousal threshold they take less time to mate and mate indiscriminately with large and small males. Mating quicker with larger males may be misconstrued to be due to female choice; our results suggest that the mating advantage of larger males may be more a result of heightened male activity and relatively less of female choice. Body size per se may not be a trait under selection by female choice, but size likely amplifies male activity and signal outputs in courtship, allowing them to influence female arousal threshold faster.

  18. Male traits, mating tactics and reproductive success in the buff-breasted sandpiper, Tryngites subruficollis.

    PubMed

    Lanctot; Weatherhead; Kempenaers; Scribner

    1998-08-01

    Buff-breasted sandpipers use a variety of mating tactics to acquire mates, including remaining at a single lek for most of the breeding season, attending multiple leks during the season, displaying solitarily or displaying both on leks and solitarily. We found that differences in body size, body condition, fluctuating asymmetry scores, wing coloration, territory location and behaviour (attraction, solicitation and agonistic) did not explain the observed variation in mating tactics used by males. Which males abandoned versus returned to leks was also not related to morphology or behaviour, and there was no tendency for males to join leks that were larger or smaller than the lek they abandoned. These results suggest that male desertion of leks was not dependent on a male's characteristics nor on the size of the lek he was presently attending. Males did join leks with larger males than their previous lek, perhaps to mate with females attracted to these larger 'hotshot' males. Males at both leks and solitary sites successfully mated. Lek tenure did not affect mating success, although lekking males appeared to mate more frequently than solitary males. Courtship disruption and to a lesser extent, female mimicry, were effective at preventing females from mating at leks, and may offer a partial explanation for female mating off leks. Our analysis that combined all males together within a year (regardless of mating tactic) indicated that males that attended leks for longer periods of time and that had fewer wing spots were significantly more likely to mate. Given some evidence that wing spotting declines with age, and that females inspect male underwings during courtship, the latter result suggests that female choice may play some role in determining male success. We suggest that male buff-breasted sandpipers may use alternative mating tactics more readily than males in other 'classic' lek-breeding species because: (1) unpredictable breeding conditions in this species' high

  19. Male traits, mating tactics and reproductive success in the buff-breasted sandpiper, Tryngites subruficollis

    USGS Publications Warehouse

    Lanctot, Richard B.; Weatherhead, Patrick J.; Kempenaers, Bart; Scribner, Kim T.

    1998-01-01

    Buff-breasted sandpipers use a variety of mating tactics to acquire mates, including remaining at a single lek for most of the breeding season, attending multiple leks during the season, displaying solitarily or displaying both on leks and solitarily. We found that differences in body size, body condition, fluctuating asymmetry scores, wing coloration, territory location and behaviour (attraction, solicitation and agonistic) did not explain the observed variation in mating tactics used by males. Which males abandoned versus returned to leks was also not related to morphology or behaviour, and there was no tendency for males to join leks that were larger or smaller than the lek they abandoned. These results suggest that male desertion of leks was not dependent on a male's characteristics nor on the size of the lek he was presently attending. Males did join leks with larger males than their previous lek, perhaps to mate with females attracted to these larger 'hotshot' males. Males at both leks and solitary sites successfully mated. Lek tenure did not affect mating success, although lekking males appeared to mate more frequently than solitary males. Courtship disruption and to a lesser extent, female mimicry, were effective at preventing females from mating at leks, and may offer a partial explanation for female mating off leks. Our analysis that combined all males together within a year (regardless of mating tactic) indicated that males that attended leks for longer periods of time and that had fewer wing spots were significantly more likely to mate. Given some evidence that wing spotting declines with age, and that females inspect male underwings during courtship, the latter result suggests that female choice may play some role in determining male success. We suggest that male buff-breasted sandpipers may use alternative mating tactics more readily than males in other 'classic' lek-breeding species because: (1) unpredictable breeding conditions in this species' high

  20. Female sticklebacks use male coloration in mate choice and hence avoid parasitized males

    NASA Astrophysics Data System (ADS)

    Milinski, Manfred; Bakker, Theo C. M.

    1990-03-01

    AN important problem in evolutionary biology since the time of Darwin has been to understand why females preferentially mate with males handicapped by secondary sexual ornaments1-3. One hypothesis of sexual selection theory is that these ornaments reliably reveal the male's condition4-6, which can be affected for example by parasites4,7-13. Here we show that in the three-spined stickleback (Gasterosteus aculeatus) the intensity of male red breeding coloration positively correlates with physical condition. Gravid females base their active mate choice on the intensity of the male's red coloration. Choice experiments under green light prevent the use of red colour cues by females, and males that were previously preferred are now chosen no more than randomly, although the courtship behaviour of the males remains unchanged. Parasitieation causes a deterioration in the males' condition and a decrease in the intensity of their red coloration. Tests under both lighting conditions reveal that the females recognize the formerly parasitized males by the lower intensity of their breeding coloration. Female sticklebacks possibly select a male with a good capacity for paternal care14 but if there is additive genetic variation for parasite resistance, then they might also select for resistance genes, as proposed by Hamilton and Zuk4.

  1. Mate-locating behavior of the butterfly Lethe diana (Lepidoptera: Satyridae): do males diurnally or seasonally change their mating strategy?

    PubMed

    Takeuchi, Tsuyoshi

    2010-10-01

    The mate-locating behavior of male butterflies has been classified into two major types, territorial and patrolling. Territorial males defend a specific site, whereas patrolling males fly around a wider area without having to defend a site. In this study, I investigated the use of these tactics by males of the satyrine butterfly, Lethe diana. A previous study suggested that the males of L. diana change their mate-locating behavior during the day (they patrol in the morning and defend territories in the afternoon) and that patrolling is the primary mating strategy, whereas defending territories is a supplementary one. In the present study, I found that the daily activity pattern of the males of L. diana was similar to that described in the previous study: males often flew around in the morning and competed for territories in the afternoon. However, contrary to the previous study, all courtships and copulations were performed within male territories during their territorial activity. Closer observations revealed that copulations found in male territories were achieved by the owner of the territory. Males tended to feed in the morning, suggesting that the males flying in the morning searched for food rather than females. I conclude that territory holding is the primary male matelocating tactic in L. diana. I further found that, in summer, males exhibited territorial behavior later than in spring or autumn, which may be a strategy for preventing heat stress.

  2. The Effects of Perceived Mating Opportunities on Patterns of Reproductive Investment by Male Guppies

    PubMed Central

    Barrett, Luke T.; Evans, Jonathan P.; Gasparini, Clelia

    2014-01-01

    Males pay considerable reproductive costs in acquiring mates (precopulatory sexual selection) and in producing ejaculates that are effective at fertilising eggs in the presence of competing ejaculates (postcopulatory sexual selection). Given these costs, males must balance their reproductive investment in a given mating to optimise their future reproductive potential. Males are therefore expected to invest in reproduction prudently according to the likelihood of obtaining future matings. In this study we tested this prediction by determining whether male reproductive investment varies with expected future mating opportunities, which were experimentally manipulated by visually exposing male guppies (Poecilia reticulata) to high or low numbers of females in the absence of competing males. Our experiment did not reveal consistent effects of perceived future mating opportunity on either precopulatory (male mate choice and mating behaviour) or postcopulatory (sperm quality and quantity) investment. However, we did find that male size and female availability interacted to influence mating behaviour; large males visually deprived of females during the treatment phase became more choosy and showed greater interest in their preferred female than those given continuous visual access to females. Overall, our results suggest males tailor pre- rather than postcopulatory traits according to local female availability, but critically, these effects depend on male size. PMID:24705713

  3. Male mating history and body size influence female fecundity and longevity of the dengue vector Aedes aegypti.

    PubMed

    Helinski, Michelle E H; Harrington, Laura C

    2011-03-01

    Male reproductive success is dependent on insemination success and reproductive output. During mating, male mosquitoes transfer not just sperm, but also seminal fluid proteins that may have profound effects on mated female biology and behavior. In this study, we investigated the role of male body size and mating history on semen depletion, female longevity, and reproductive success in Aedes aegypti L. Small and large males were mated in rapid succession with up to five females. Our results indicate that large males had greater mating capacity than small males. A reduction in fecundity by >50% was observed in females that were fourth to mate with small males in comparison with females that mated earlier in sequence. For females mated to large males, this reduction became evident for females that mated fifth in sequence. No loss of fertility (measured as hatch rate) was observed in females that were third-fifth in mating sequence compared with females mated to virgin males. When females were maintained on a low-quality (5% sucrose) diet, those mated to virgin males had a greater longevity compared with females mated third in sequence. We conclude that small males experience more rapid seminal depletion than large males, and discuss the role of semen depletion in the mated female. Our results contribute toward a better understanding of the complexity of Ae. aegypti mating biology and provide refined estimates of mating capacity for genetic control efforts.

  4. Tropics accelerate the evolution of hybrid male sterility in Drosophila.

    PubMed

    Yukilevich, Roman

    2013-06-01

    Understanding the evolutionary mechanisms that facilitate speciation and explain global patterns of species diversity has remained a challenge for decades. The most general pattern of species biodiversity is the latitudinal gradient, whereby species richness increases toward the tropics. Although such a global pattern probably has a multitude of causes, recent attention has focused on the hypothesis that speciation and the evolution of reproductive isolation occur faster in the tropics. Here, I tested this prediction using a dataset on premating and postzygotic isolation between recently diverged Drosophila species. Results showed that while the evolution of premating isolation was not greater between tropical Drosophila relative to nontropical species, postzygotic isolation evolved faster in the tropics. In particular, hybrid male sterility was much greater among tropical Drosophila compared to nontropical species pairs of similar genetic age. Several testable explanations for the novel pattern are discussed, including greater role for sterility-inducing bacterial endosymbionts in the tropics and more intense sperm-sperm competition or sperm-egg sexual conflict in the tropics. The results imply that processes of speciation in the tropics may evolve at different rates or may even be somewhat different from those at higher latitudes.

  5. Effects of sodium puddling on male mating success, courtship and flight in a swallowtail butterfly

    PubMed Central

    Mitra, Chandreyee; Reynoso, Edgar; Davidowitz, Goggy; Papaj, Daniel

    2016-01-01

    In many Lepidoptera species usually only males puddle for sodium. Two explanations have been offered for this: (1) neuromuscular activity: males need increased sodium for flight because they are more active flyers than females; and (2) direct benefits: sodium is a type of direct benefit provided by males to females via ejaculate during mating. Surprisingly, there is little direct experimental evidence for either of these. In this study, we examined both explanations using the pipevine swallowtail butterfly, Battus philenor L. If sodium increases neuromuscular activity, males consuming sodium should be better fliers than males without sodium. If males collect sodium for nuptial gifts that benefit their mates, males consuming sodium may have greater mating success than males without sodium. In that case, females then need an honest cue/signal of the quality of male-provided direct benefits that they can assess before mating. If sodium affects male courtship flight by increasing neuromuscular activity, how a male courts could serve as such a premating cue/signal of male benefit quality. Therefore, sodium may benefit males in terms of obtaining mates by increasing their neuromuscular activity. In this study we found that males that consumed sodium courted more vigorously and had greater mating success than males that consumed water. In addition, the courtship displays of males consuming sodium were significantly different from those of males consuming water, providing a possible honest cue/signal of male benefit quality that females can assess. Interestingly, we did not find evidence that sodium consumption affects male flight outside of courtship. That only aspects of male flight related to mating were affected by sodium, while aspects of general flight were not, is consistent with the idea that sodium may benefit males in terms of obtaining mates via effects on neuromuscular activity. PMID:27103748

  6. Auxins reverse plant male sterility caused by high temperatures

    PubMed Central

    Sakata, Tadashi; Oshino, Takeshi; Miura, Shinya; Tomabechi, Mari; Tsunaga, Yuta; Higashitani, Nahoko; Miyazawa, Yutaka; Takahashi, Hideyuki; Watanabe, Masao; Higashitani, Atsushi

    2010-01-01

    With global warming, plant high temperature injury is becoming an increasingly serious problem. In wheat, barley, and various other commercially important crops, the early phase of anther development is especially susceptible to high temperatures. Activation of auxin biosynthesis with increased temperatures has been reported in certain plant tissues. In contrast, we here found that under high temperature conditions, endogenous auxin levels specifically decreased in the developing anthers of barley and Arabidopsis. In addition, expression of the YUCCA auxin biosynthesis genes was repressed by increasing temperatures. Application of auxin completely reversed male sterility in both plant species. These findings suggest that tissue-specific auxin reduction is the primary cause of high temperature injury, which leads to the abortion of pollen development. Thus, the application of auxin may help sustain steady yields of crops despite future climate change. PMID:20421476

  7. Auxins reverse plant male sterility caused by high temperatures.

    PubMed

    Sakata, Tadashi; Oshino, Takeshi; Miura, Shinya; Tomabechi, Mari; Tsunaga, Yuta; Higashitani, Nahoko; Miyazawa, Yutaka; Takahashi, Hideyuki; Watanabe, Masao; Higashitani, Atsushi

    2010-05-11

    With global warming, plant high temperature injury is becoming an increasingly serious problem. In wheat, barley, and various other commercially important crops, the early phase of anther development is especially susceptible to high temperatures. Activation of auxin biosynthesis with increased temperatures has been reported in certain plant tissues. In contrast, we here found that under high temperature conditions, endogenous auxin levels specifically decreased in the developing anthers of barley and Arabidopsis. In addition, expression of the YUCCA auxin biosynthesis genes was repressed by increasing temperatures. Application of auxin completely reversed male sterility in both plant species. These findings suggest that tissue-specific auxin reduction is the primary cause of high temperature injury, which leads to the abortion of pollen development. Thus, the application of auxin may help sustain steady yields of crops despite future climate change.

  8. Parthenogenesis maintains male sterility in a gynodioecious orchid.

    PubMed

    Huang, Shuang-Quan; Lu, Yang; Chen, Ying-Zhuo; Luo, Yi-Bo; Delph, Lynda F

    2009-10-01

    The invasion of male-sterile (female) individuals into hermaphroditic populations, leading to gynodioecy, is common in flowering plants. Both theoretical and empirical studies have shown that as the frequency of females increases in a population, pollen limitation reduces seed production more in females than in hermaphrodites, leading to higher fitness for hermaphrodites and a consequent decrease in female frequency. Here we show that contrary to this expectation, females of the gynodioecious orchid Satyrium ciliatum are maintained only in populations that experience high pollen limitation caused by low pollinator service and high pollen herbivory. This species avoids the typical problem of pollen limitation for seed production and can therefore maintain high frequencies of females in pollen-limited populations because females produce more seeds than hermaphrodites via facultative parthenogenesis in the absence of pollinia. Our results therefore demonstrate that parthenogenesis is a novel mechanism favoring the maintenance of gynodioecy.

  9. Male-male sexual behavior in Japanese quail: being "on top" reduces mating and fertilization with females.

    PubMed

    Adkins-Regan, Elizabeth

    2014-10-01

    Male Japanese quail (Coturnix japonica) engage in vigorous same-sex sexual interactions that have been interpreted as aggressive behavior reflecting dominance relationships. The consequences of this behavior for reproductive success, and whether it is a form of competition over mating and fertilization, are unclear. Three experiments were conducted to determine the effect of seeing or interacting with another male on a male's subsequent mating and fertilization success with females. A vigorous interaction with another male in which the subject performed more cloacal contact movements (movements to try to make contact with the other bird's cloacal opening) reduced subsequent mating and fertilization success with a female to a similar extent as a prior mating with a different female. Receiving one or more cloacal contacts from another male was less detrimental for subsequent success. The mere presence of another (stimulus) male delayed mating initiation in those male subjects that approached the stimulus first instead of the female. These results do not support the idea that the male "on top" in male-male sexual interactions is the dominant bird who goes on to achieve greater reproductive success. Instead, the results are consistent with male-male sexual behavior as an occasionally costly by-product of strong mating motivation.

  10. Do female Nicrophorus vespilloides reduce direct costs by choosing males that mate less frequently?

    PubMed Central

    Mazué, G. P. F.; Carter, M. J.; Head, M. L.; Moore, A. J.; Royle, N. J.

    2016-01-01

    Sexual conflict occurs when selection to maximize fitness in one sex does so at the expense of the other sex. In the burying beetle Nicrophorus vespilloides, repeated mating provides assurance of paternity at a direct cost to female reproductive productivity. To reduce this cost, females could choose males with low repeated mating rates or smaller, servile males. We tested this by offering females a dichotomous choice between males from lines selected for high or low mating rate. Each female was then allocated her preferred or non-preferred male to breed. Females showed no preference for males based on whether they came from lines selected for high or low mating rates. Pairs containing males from high mating rate lines copulated more often than those with low line males but there was a negative relationship between female size and number of times she mated with a non-preferred male. When females bred with their preferred male the number of offspring reared increased with female size but there was no such increase when breeding with non-preferred males. Females thus benefited from being choosy, but this was not directly attributable to avoidance of costly male repeated mating. PMID:26979560

  11. Biased sex ratio and low population density increase male mating success in the bug Nysius huttoni (Heteroptera: Lygaeidae)

    NASA Astrophysics Data System (ADS)

    Wang, Qiao; He, Xiong Zhao; Yang, Linghuan; Hedderley, Duncan; Davis, Lorraine K.

    2009-01-01

    Demographic factors such as operational sex ratio (OSR) and local population density (LPD) are temporally and spatially dynamic in the natural environment but the influence of these variables on male mating success and the mechanisms behind it are still poorly understood and highly controversial. Here, we manipulated the OSR and LPD of a seed bug, Nysius huttoni, and carried out a series of mating trials to test how these variables affected male mating success. The two demographic factors had no significant interactions, suggesting that they affect male mating success independently in N. huttoni. In this species male mating success was significantly higher in both male- and female-biased OSR than in even OSR. It is suggested that, in male-biased OSR, the increased intensity of competition and interference does not result in lower male mating success; rather, males may make more effort in courting and females may have more chance to encounter better males, resulting in higher male mating success. In female-biased OSR, females may become less choosy and less likely to reject male mating attempt, leading to the higher male mating success. Lower male mating success in N. huttoni in high LPD may be due to increased interference between males and/or delayed female receptiveness for mating. OSR had a stronger effect on male mating success than LPD in N. huttoni, suggesting that OSR and LPD affect mating success in different ways and intensities.

  12. Sterilizing effects of cobalt-60 and cesium-137 radiation on male sea lampreys

    USGS Publications Warehouse

    Hanson, L.H.

    1990-01-01

    Male spawning-run sea lampreys Petromyzon marinus were exposed to various doses of cobalt-60 or cesium-137 radiation in an attempt to sterilize them for use in a program for controlling sea lampreys through the release of sterile males. Males captured and irradiated during the early part of the upstream migration were not effectively sterilized at the doses tested. After irradiation, the sea lampreys were more susceptible to fungal infections by Saprolegnia sp., and many died without attempting to spawn. Males captured and irradiated during the middle and late parts of the spawning migration were effectively sterilized at a dose of 2,000 rads. However, some radiation-induced mortality was observed in males captured and irradiated during the middle part of the spawning migration. Radiation is not as effective as the chemosterilant bisazir for sterilizing male sea lampreys.

  13. Quantitative Trait Locus Analysis of Mating Behavior and Male Sex Pheromones in Nasonia Wasps

    PubMed Central

    Diao, Wenwen; Mousset, Mathilde; Horsburgh, Gavin J.; Vermeulen, Cornelis J.; Johannes, Frank; van de Zande, Louis; Ritchie, Michael G.; Schmitt, Thomas; Beukeboom, Leo W.

    2016-01-01

    A major focus in speciation genetics is to identify the chromosomal regions and genes that reduce hybridization and gene flow. We investigated the genetic architecture of mating behavior in the parasitoid wasp species pair Nasonia giraulti and Nasonia oneida that exhibit strong prezygotic isolation. Behavioral analysis showed that N. oneida females had consistently higher latency times, and broke off the mating sequence more often in the mounting stage when confronted with N. giraulti males compared with males of their own species. N. oneida males produce a lower quantity of the long-range male sex pheromone (4R,5S)-5-hydroxy-4-decanolide (RS-HDL). Crosses between the two species yielded hybrid males with various pheromone quantities, and these males were used in mating trials with females of either species to measure female mate discrimination rates. A quantitative trait locus (QTL) analysis involving 475 recombinant hybrid males (F2), 2148 reciprocally backcrossed females (F3), and a linkage map of 52 equally spaced neutral single nucleotide polymorphism (SNP) markers plus SNPs in 40 candidate mating behavior genes revealed four QTL for male pheromone amount, depending on partner species. Our results demonstrate that the RS-HDL pheromone plays a role in the mating system of N. giraulti and N. oneida, but also that additional communication cues are involved in mate choice. No QTL were found for female mate discrimination, which points at a polygenic architecture of female choice with strong environmental influences. PMID:27172207

  14. Evaluating the potential of the sterile insect technique for malaria control: relative fitness and mating compatibility between laboratory colonized and a wild population of Anopheles arabiensis from the Kruger National Park, South Africa

    PubMed Central

    2011-01-01

    Background The successful suppression of a target insect population using the sterile insect technique (SIT) partly depends on the premise that the laboratory insects used for mass rearing are genetically compatible with the target population, that the mating competitiveness of laboratory reared males is at least comparable to that of their wild counterparts, and that mass rearing and sterilization processes do not in themselves compromise male fitness to a degree that precludes them from successfully competing for mates in the wild. This study investigated the fitness and sexual cross-compatibility between samples of field collected and laboratory reared An. arabiensis under laboratory conditions. Results The physiological and reproductive fitness of the MALPAN laboratory strain is not substantially modified with respect to the field population at Malahlapanga. Further, a high degree of mating compatibility between MALPAN and the Malahlapanga population was established based on cross-mating experiments. Lastly, the morphological characteristics of hybrid ovarian polytene chromosomes further support the contention that the MALPAN laboratory colony and the An. arabiensis population at Malahlapanga are genetically homogenous and therefore compatible. Conclusions It is concluded that the presence of a perennial and isolated population of An. arabiensis at Malahlapanga presents a unique opportunity for assessing the feasibility of SIT as a malaria vector control option. The MALPAN laboratory colony has retained sufficient enough measures of reproductive and physiological fitness to present as a suitable candidate for male sterilization, mass rearing and subsequent mass release of sterile males at Malahlapanga in order to further assess the feasibility of SIT in a field setting. PMID:22041133

  15. Impact of male mating history on the temporal sperm dynamics of Choristoneura rosaceana and C. fumiferana females.

    PubMed

    Marcotte, Mireille; Delisle, Johanne; McNeil, Jeremy N

    2005-05-01

    In the oblique-banded leafroller, Choristoneura rosaceana, and the spruce budworm, C. fumiferana, male reproductive performance decreases with consecutive matings. While the onset time of mating did not vary, the time spent mating was longer in mated than in virgin males. Furthermore, a decline observed in the spermatophore mass with successive matings was associated with a concomitant decline in its apyrene and eupyrene spermatozoa content. In the hours following mating, spermatozoa migrate from the spermatophore, located in the bursa copulatrix, to the spermatheca. Regardless of the male's previous mating history, the number of apyrene sperm dropped rapidly in the days following mating whereas the number of eupyrene spermatozoa declined gradually. As the temporal pattern of sperm movement was similar in all treatments, females mated with previously-mated males would suffer from sperm shortage sooner than those mated with virgins. Large C. rosaceana females stored more apyrene spermatozoa in their spermatheca than small ones, irrespective of the time after mating or male mating history, while only large females mated with once-mated males received more apyrene sperm and accessory gland secretions than small ones mated with virgin or twice-mated males. The results obtained in this study are discussed in relation with their potential impact on the reproductive success of both sexes.

  16. Female and Male Moths Display Different Reproductive Behavior when Facing New versus Previous Mates

    PubMed Central

    Lu, Qin; Xu, Jin; Ye, Hui

    2014-01-01

    Multiple mating allows females to obtain material (more sperm and nutrient) and/or genetic benefits. The genetic benefit models require sperm from different males to fertilize eggs competitively or the offspring be fathered by multiple males. To maximize genetic benefits from multiple mating, females have evolved strategies to prefer novel versus previous mates in their subsequent matings. However, the reproductive behavior during mate encounter, mate choice and egg laying in relation to discrimination and preference between sexes has been largely neglected. In the present study, we used novel and previous mate treatments and studied male and female behavior and reproductive output in Spodoptera litura. The results of this study do not support the sperm and nutrient replenishment hypotheses because neither the number of mates nor the number of copulations achieved by females significantly increased female fecundity, fertility and longevity. However, females showed different oviposition patterns when facing new versus previous mates by slowing down oviposition, which allows the last male has opportunities to fertilize her eggs and the female to promote offspring diversity. Moreover, females that have novel males present called earlier and more than females that have their previous mates present, whereas no significant differences were found on male courtship between treatments. These results suggest that S. litura females can distinguish novel from previous mates and prefer the former, whereas males generally remate regardless of whether the female is a previous mate or not. In S. litura, eggs are laid in large clusters and offspring competition, inbreeding and disease transfer risks are thus increased. Therefore, offspring diversity should be valuable for S. litura, and genetic benefits should be the main force behind the evolution of female behavioral strategies found in the present study. PMID:25290195

  17. Feminization of pheromone-sensing neurons affects mating decisions in Drosophila males.

    PubMed

    Lu, Beika; Zelle, Kathleen M; Seltzer, Raya; Hefetz, Abraham; Ben-Shahar, Yehuda

    2014-02-15

    The response of individual animals to mating signals depends on the sexual identity of the individual and the genetics of the mating targets, which represent the mating social context (social environment). However, how social signals are sensed and integrated during mating decisions remains a mystery. One of the models for understanding mating behaviors in molecular and cellular terms is the male courtship ritual in the fruit fly (Drosophila melanogaster). We have recently shown that a subset of gustatory receptor neurons (GRNs) that are enriched in the male appendages and express the ion channel ppk23 play a major role in the initiation and maintenance of male courtship via the perception of cuticular contact pheromones, and are likely to represent the main chemosensory pathway that influences mating decisions by males. Here we show that genetic feminization of ppk23-expressing GRNs in male flies resulted in a significant increase in male-male sexual attraction without an apparent impact on sexual attraction to females. Furthermore, we show that this increase in male-male sexual attraction is sensory specific, which can be modulated by variable social contexts. Finally, we show that feminization of ppk23-expressing sensory neurons lead to major transcriptional shifts, which may explain the altered interpretation of the social environment by feminized males. Together, these data indicate that the sexual cellular identity of pheromone sensing GRNs plays a major role in how individual flies interpret their social environment in the context of mating decisions.

  18. DNA methylation affected by male sterile cytoplasm in rice (Oryza sativa L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Male sterile cytoplasm plays an important role in hybrid rice and cytoplasmic effects are sufficiently documented. However, no reports are available on DNA methylation affected by male sterile cytoplasm in hybrid rice. We used a methylation sensitive amplified polymorphism (MSAP) technique to charac...

  19. Diverse germplasm to devleop male-sterile lines for hybrid breeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hybrid rice breeding in the US has depended largely upon male-sterile lines originating in China or from other Asian sources. By contrast, the program in Arkansas has developed all of its male-sterile lines at Stuttgart,AR using germplasm accessions available in the USDA Rice Germplasm Collection st...

  20. Methoprene treatment reduces the pre-copulatory period in Anastrepha fraterculus (Diptera: Tephritidae) sterile males

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anastrepha fraterculus is a major fruit pest in South America. Ongoing studies encourage the implementation of the sterile insect technique (SIT) against this pest. Sexual readiness of sterile males is a key point for SIT. The time required for A. fraterculus males to become sexually mature is unkn...

  1. Hybridization using cytoplasmic male sterility and herbicide tolerance from nuclear genes

    SciTech Connect

    Beversdorf, W.D.; Erickson, L.R.; Grant, I.

    1987-04-14

    An improved process is described for producing a substantially homogeneous population of plants of a predetermined hybrid variety of a crop which is capable of undergoing both self-pollination and cross-pollination. This process comprises: growing in a first planting area a substantially random population of cytoplasmic male sterile plants which exhibit tolerance to at least one herbicide attributable solely to homozygous dominant nuclear genes, and male fertile plants which are capable of pollinating the cytoplasmic male sterile plants and which lack the herbicide tolerance because the presence of homozygous recessive nuclear genes for such trait. The cytoplasmic male sterile plants and the male fertile plants are pollinated with pollen derived from the male fertile plants. Seed is formed on the cytoplasmic male sterile plants and on the male fertile plants. Harvesting in bulk the seed is formed on the plants of the first planting area.

  2. Socio-demographic factors intensifying male mating competition exacerbate male mortality rates.

    PubMed

    Kruger, Daniel J

    2010-05-07

    Sex differences in mortality rates stem from a complex set of genetic, physiological, psychological, and social causes whose influences and interconnections are best understood in an integrative evolutionary life history framework. Although there are multiple levels of mechanisms contributing to sex based disparities in mortality rates, the intensity of male mating competition in a population may have a crucial role in shaping the level of excess male mortality. The degree of variation and skew in male reproductive success may shape the intensity of male mating competition, leading to riskier behavioral and physiological strategies. This study examines three socio-demographic factors related to variation in human male reproductive success; polygyny, economic inequality, and the population ratio of reproductively viable men to women across nations with available data. The degrees of economic inequality and polygyny explained unique portions in the sex difference in mortality rates, these predictors accounted for 53% of the variance. The population ratio of reproductively viable men to women did not explain any additional variance. These results demonstrate the association between social conditions and health outcomes in modern nations, as well as the power of an evolutionary life history framework for understanding important social issues.

  3. Mothers matter! Maternal support, dominance status and mating success in male bonobos (Pan paniscus).

    PubMed

    Surbeck, Martin; Mundry, Roger; Hohmann, Gottfried

    2011-02-22

    Variation in male mating success is often related to rank differences. Males who are unable to monopolize oestrous females alone may engage in coalitions, thus enhancing their mating success. While studies on chimpanzees and dolphins suggest that coalitions are independent of kinship, information from female philopatric species shows the importance of kin support, especially from mothers, on the reproductive success of females. Therefore, one might expect a similar effect on sons in male philopatric species. We evaluate mating success determinants in male bonobos using data from nine male individuals from a wild population. Results reveal a steep, linear male dominance hierarchy and a positive correlation between dominance status and mating success. In addition to rank, the presence of mothers enhances the mating success of sons and reduces the proportion of matings by the highest ranking male. Mothers and sons have high association rates and mothers provide agonistic aid to sons in conflicts with other males. As bonobos are male-philopatric and adult females occupy high dominance status, maternal support extends into adulthood and females have the leverage to intervene in male conflicts. The absence of female support to unrelated males suggests that mothers gain indirect fitness benefits by supporting their sons.

  4. Why do territorial male Tengmalm's owls fail to obtain a mate?

    PubMed

    Hakkarainen, Harri; Korpimäki, Erkki

    1998-05-01

    Non-breeding may occur because non-breeders are immature or somehow physiologically incapable of breeding, or because of a lack of resources (e.g. food resources, mating partners) needed to breed. There is, however, a lack of experimental evidence on whether bachelor males possessing territories and nest-sites are able to breed when supplemented with extra food or provided with mating partners. In vole-eating Tengmalm's owl, Aegolius funereus, we provided supplementary food and transferred females in nest-boxes of non-breeding males. Bachelor males that we supplemented with food did not attract mates at a higher frequency than unfed control males, which suggests that a lack of food did not influence the ability to attract a mating partner. In contrast, bachelor males presented with a female seemed to breed more frequently than bachelor males in the control group without mate addition. This suggests that scarcity of females may be an important reason for the high proportion of non-breeding males in the population (c. 25%) and excludes the possibility that non-breeding males are physiologically unable to breed. The operational sex ratio of the owl population at the time of mating may be male-biased, and some males may thus remain unpaired. Habitat and nest-box quality also seemed to be lower among bachelors than among breeding males.

  5. Condition-dependent ejaculate production affects male mating behavior in the common bedbug Cimex lectularius.

    PubMed

    Kaldun, Bettina; Otti, Oliver

    2016-04-01

    Food availability in the environment is often low and variable, constraining organisms in their resource allocation to different life-history traits. For example, variation in food availability is likely to induce condition-dependent investment in reproduction. Further, diet has been shown to affect ejaculate size, composition and quality. How these effects translate into male reproductive success or change male mating behavior is still largely unknown. Here, we concentrated on the effect of meal size on ejaculate production, male reproductive success and mating behavior in the common bedbug Cimex lectularius. We analyzed the production of sperm and seminal fluid within three different feeding regimes in six different populations. Males receiving large meals produced significantly more sperm and seminal fluid than males receiving small meals or no meals at all. While such condition-dependent ejaculate production did not affect the number of offspring produced after a single mating, food-restricted males could perform significantly fewer matings than fully fed males. Therefore, in a multiple mating context food-restricted males paid a fitness cost and might have to adjust their mating strategy according to the ejaculate available to them. Our results indicate that meal size has no direct effect on ejaculate quality, but food availability forces a condition-dependent mating rate on males. Environmental variation translating into variation in male reproductive traits reveals that natural selection can interact with sexual selection and shape reproductive traits. As males can modulate their ejaculate size depending on the mating situation, future studies are needed to elucidate whether environmental variation affecting the amount of ejaculate available might induce different mating strategies.

  6. Inhibition of female mating receptivity by male-derived extracts in two Callosobruchus species: consequences for interspecific mating.

    PubMed

    Yamane, Takashi; Miyatake, Takahisa

    2010-11-01

    We investigated the effects of injecting male-derived extracts on congeneric female receptivity in two species of Callosobruchus beetle, C. chinensis and C. maculatus. We also examined the influence of interspecific mating on female remating behaviour in these two species. Male-derived extracts reduced congeneric female receptivity in both species. As quick-acting components, extracts of C. chinensis male seminal vesicles reduced the receptivity of C. maculatus females, whereas extracts of C. maculatus male testes reduced the receptivity of C. chinensis females. As slow-acting components, extracts of male accessory glands of other species reduced the receptivity of both C. maculatus and chinensis females. After interspecific mating, the sperm of C. maculatus males were transferred to the reproductive organs of C. chinensis females, thereby reducing their receptivity. In contrast, no C. chinensis sperm were transferred to the reproductive organs of C. maculatus females; accordingly, the latter's receptivity was not reduced. Furthermore, the survival rate of C. chinensis females decreased markedly after interspecific mating. These results raise the possibility that under circumstances where populations of these two species share the same habitat, reproductive interference would occur only in the interactions between C. maculatus males and C. chinensis females.

  7. Male coercion and the costs of promiscuous mating for female chimpanzees

    PubMed Central

    Muller, Martin N; Kahlenberg, Sonya M; Emery Thompson, Melissa; Wrangham, Richard W

    2007-01-01

    For reasons that are not yet clear, male aggression against females occurs frequently among primates with promiscuous mating systems. Here, we test the sexual coercion hypothesis that male aggression functions to constrain female mate choice. We use 10 years of behavioural and endocrine data from a community of wild chimpanzees (Pan troglodytes schweinfurthii) to show that sexual coercion is the probable primary function of male aggression against females. Specifically, we show that male aggression is targeted towards the most fecund females, is associated with high male mating success and is costly for the victims. Such aggression can be viewed as a counter-strategy to female attempts at paternity confusion, and a cost of multi-male mating. PMID:17264062

  8. Genetic determination of male sterility in gynodioecious Silene nutans

    PubMed Central

    Garraud, C; Brachi, B; Dufay, M; Touzet, P; Shykoff, J A

    2011-01-01

    Gynodioecy, the coexistence of female and hermaphrodite plants within a species, is often under nuclear–cytoplasmic sex determination, involving cytoplasmic male sterility (CMS) genes and nuclear restorers. A good knowledge of CMS and restorer polymorphism is essential for understanding the evolution and maintenance of gynodioecy, but reciprocal crossing studies remain scarce. Although mitochondrial diversity has been studied in a few gynodioecious species, the relationship between mitotype diversity and CMS status is poorly known. From a French sample of Silene nutans, a gynodioecious species whose sex determination remains unknown, we chose the four most divergent mitotypes that we had sampled at the cytochrome b gene and tested by reciprocal crosses whether they carry distinct CMS genes. We show that gynodioecy in S. nutans is under nuclear–cytoplasmic control, with at least two different CMSs and up to four restorers with epistatic interactions. Female occurrence and frequency were highly dependent on the mitotype, suggesting that the level of restoration varies greatly among CMSs. Two of the mitotypes, which have broad geographic distributions, represent different CMSs and are very unequally restored. We discuss the dynamics of gynodioecy at the large-scale meta-population level. PMID:20808324

  9. Hybrid male sterility in rice controlled by interaction between divergent alleles of two adjacent genes.

    PubMed

    Long, Yunming; Zhao, Lifeng; Niu, Baixiao; Su, Jing; Wu, Hao; Chen, Yuanling; Zhang, Qunyu; Guo, Jingxin; Zhuang, Chuxiong; Mei, Mantong; Xia, Jixing; Wang, Lan; Wu, Haibin; Liu, Yao-Guang

    2008-12-02

    Sterility is common in hybrids between divergent populations, such as the indica and japonica subspecies of Asian cultivated rice (Oryza sativa). Although multiple loci for plant hybrid sterility have been identified, it remains unknown how alleles of the loci interact at the molecular level. Here we show that a locus for indica-japonica hybrid male sterility, Sa, comprises two adjacent genes, SaM and SaF, encoding a small ubiquitin-like modifier E3 ligase-like protein and an F-box protein, respectively. Most indica cultivars contain a haplotype SaM(+)SaF(+), whereas all japonica cultivars have SaM(-)SaF(-) that diverged by nucleotide variations in wild rice. Male semi-sterility in this heterozygous complex locus is caused by abortion of pollen carrying SaM(-). This allele-specific gamete elimination results from a selective interaction of SaF(+) with SaM(-), a truncated protein, but not with SaM(+) because of the presence of an inhibitory domain, although SaM(+) is required for this male sterility. Lack of any one of the three alleles in recombinant plants does not produce male sterility. We propose a two-gene/three-component interaction model for this hybrid male sterility system. The findings have implications for overcoming male sterility in inter-subspecific hybrid rice breeding.

  10. The Contribution of the Y Chromosome to Hybrid Male Sterility in House Mice

    PubMed Central

    Campbell, Polly; Good, Jeffrey M.; Dean, Matthew D.; Tucker, Priscilla K.; Nachman, Michael W.

    2012-01-01

    Hybrid sterility in the heterogametic sex is a common feature of speciation in animals. In house mice, the contribution of the Mus musculus musculus X chromosome to hybrid male sterility is large. It is not known, however, whether F1 male sterility is caused by X–Y or X-autosome incompatibilities or a combination of both. We investigated the contribution of the M. musculus domesticus Y chromosome to hybrid male sterility in a cross between wild-derived strains in which males with a M. m. musculus X chromosome and M. m. domesticus Y chromosome are partially sterile, while males from the reciprocal cross are reproductively normal. We used eight X introgression lines to combine different X chromosome genotypes with different Y chromosomes on an F1 autosomal background, and we measured a suite of male reproductive traits. Reproductive deficits were observed in most F1 males, regardless of Y chromosome genotype. Nonetheless, we found evidence for a negative interaction between the M. m. domesticus Y and an interval on the M. m. musculus X that resulted in abnormal sperm morphology. Therefore, although F1 male sterility appears to be caused mainly by X-autosome incompatibilities, X–Y incompatibilities contribute to some aspects of sterility. PMID:22595240

  11. Sterilization.

    PubMed

    Peterson, Herbert B

    2008-01-01

    Worldwide, sterilization (tubal sterilization and vasectomy) is used by more people than any other method of contraception. All techniques of tubal sterilization in widespread use in the United States have low risks of surgical complications. Although tubal sterilization is highly effective, the risk of pregnancy varies by age and method of occlusion. Pregnancies can occur many years after the procedure, and when they do, the risk of ectopic gestation is high. There is now strong evidence against the existence of a post-tubal ligation syndrome of menstrual abnormalities. Although women who have undergone tubal sterilization are more likely than other women to undergo hysterectomy subsequently, there is no known biologic basis for this relationship. Although sterilization is intended to be permanent, expressions of regret and requests for reversal are not uncommon and are much more likely to occur among women sterilized at young ages. Tubal sterilization has little or no effect on sexual function for most women. Vasectomy is less likely than tubal sterilization to result in serious complications. Minor complications, however, are not uncommon. Vasectomy does not increase the risk of heart disease, and available evidence argues against an increase in the risk of prostate cancer, testicular cancer, or overall mortality. Whether a postvasectomy pain syndrome exists remains controversial. Although the long-term effectiveness of vasectomy is less well-studied than that for tubal sterilization, it seems likely to be at least as effective. Intrauterine devices and progestin implants are long-acting, highly effective alternatives to sterilization.

  12. Mating Experience and Food Deprivation Modulate Odor Preference and Dispersal in Drosophila melanogaster Males

    PubMed Central

    Wang, Shu-Ping; Guo, Wei-Yan; Muhammad, Shahid Arain; Chen, Rui-Rui; Mu, Li-Li; Li, Guo-Qing

    2014-01-01

    Rotting fruits offer all of the known resources required for the livelihood of Drosophila melanogaster Meigen (Diptera: Drosophilidae). During fruit fermentation, carbohydrates and proteins are decomposed to produce volatile alcohols and amines, respectively. It is hypothesized that D. melanogaster adults can detect these chemical cues at a distance to identify and locate the decaying fruits. In the present paper, we compared the olfactory responses and movement of male flies varying in mating status and nutritional state to methanol, ethanol, and ammonia sources using a glass Y-tube olfactometer. In general, ethanol vapor at low to moderate concentrations repelled more hungry mated males than satiated ones. In contrast, methanol showed little difference in the attractiveness to males at different nutritional states and mating status. Moreover, ammonia attracted more hungry mated males. The attractiveness increased almost linearly with ammonia concentration from lowest to highest. When ammonia and artificial diet were put together in the odor arm, the responses of male flies to mixed odor mimicked the response to ammonia. Furthermore, odorant concentration, mating status, and nutritional state affected the flies' dispersal. Mated and starved males dispersed at a higher rate than virgin and satiated ones. Thus, our results showed that starved, mated males increased dispersal and preferred ammonia that originated from protein. PMID:25368075

  13. Consequences of snowy winters on male mating strategies and reproduction in a mountain ungulate.

    PubMed

    Apollonio, Marco; Brivio, Francesca; Rossi, Iva; Bassano, Bruno; Grignolio, Stefano

    2013-09-01

    Alternative mating tactics (AMTs) are intrasexual variants in mating behaviour of several species ranging from arthropods to mammals. Male AMTs coexist between and within populations. In particular, male ungulates rarely adopt just one tactic throughout their lifetime. Tactics commonly change according to internal factors (age, body size, condition) and external conditions (weather, resources, predation, animal density). However, the influence of weather has not yet been investigated in upper vertebrates. Such influence may be relevant in species whose rutting period occurs late in fall or in winter, when environmental conditions and the snow cover in particular may vary considerably. We detected two AMTs in Alpine ibex (Capra ibex) males: older and full-grown males mainly adopted the tending tactic, while younger males usually pursued an alternative one (coursing tactic). Weather was found to influence the use of AMTs by males: in snowy mating seasons, the coursing tactic was no longer used due to difficulties in moving through deep snow. In snowy rutting periods, males appeared to delay or even avoid mating activities and a decrease of births was reported in the second part of the following birth season. Snow cover may have a negative effect on population dynamics by reducing the recruitment and on population genetic variability, as a consequence of poorer mating opportunities. Studies on factors affecting mating behaviour and leading to a reduced availability of mates and a decrease in female productivity are especially relevant in species, like Alpine ibex, whose genetic variability is low.

  14. Effect of mating activity and dominance rank on male masturbation among free-ranging male rhesus macaques.

    PubMed

    Dubuc, Constance; Coyne, Sean P; Maestripieri, Dario

    2013-11-01

    The adaptive function of male masturbation is still poorly understood, despite its high prevalence in humans and other animals. In non-human primates, male masturbation is most frequent among anthropoid monkeys and apes living in multimale-multifemale groups with a promiscuous mating system. In these species, male masturbation may be a non-functional by-product of high sexual arousal or be adaptive by providing advantages in terms of sperm competition or by decreasing the risk of sexually transmitted infections. We investigated the possible functional significance of male masturbation using behavioral data collected on 21 free-ranging male rhesus macaques (Macaca mulatta) at the peak of the mating season. We found some evidence that masturbation is linked to low mating opportunities: regardless of rank, males were most likely to be observed masturbating on days in which they were not observed mating, and lower-ranking males mated less and tended to masturbate more frequently than higher-ranking males. These results echo the findings obtained for two other species of macaques, but contrast those obtained in red colobus monkeys (Procolobus badius) and Cape ground squirrels (Xerus inauris). Interestingly, however, male masturbation events ended with ejaculation in only 15% of the observed masturbation time, suggesting that new hypotheses are needed to explain masturbation in this species. More studies are needed to establish whether male masturbation is adaptive and whether it serves similar or different functions in different sexually promiscuous species.

  15. Molecular mapping of a new induced gene for nuclear male sterility in sunflower (Helianthus annuus L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new NMS line, NMS HA89-872, induced by mitomycin C and streptomycin carries a single recessive male-sterile gene ms6. An F2 population of 88 plants was obtained from a cross between nuclear male-sterile mutant NMS HA89-872 (msms) and male-fertile line RHA271 (MsMs). 225 SSR primers and 9 RFLP-deri...

  16. Sexual behavior across ovarian cycles in wild black howler monkeys (Alouatta pigra): male mate guarding and female mate choice.

    PubMed

    Van Belle, Sarie; Estrada, Alejandro; Ziegler, Toni E; Strier, Karen B

    2009-02-01

    We studied two multimale-multifemale groups of black howler monkeys (Alouatta pigra) during a 14-month study (June 2006-July 2007) in Palenque National Park, Mexico to evaluate the ways in which their sexual behavior changes across ovarian cycles. We analyzed 231 fecal samples, collected every 2.2+/-1.4 days from five females. For four females, estradiol and progesterone profiles revealed an average (+/-SE) cycle length of 18.3+/-1.4 days. Copulations occurred significantly more frequently during the periovulatory period (POP), defined as the estimated day of ovulation +/-3 days (N=18). This was largely the result of cycling females soliciting sexual interactions during their POPs. Females directed their solicitations significantly more often toward "central" males of their group, who had close spatial associations with females at other times, compared with "noncentral" males, who did not associate closely with females. Central males rarely solicited sexual interactions, but instead monitored the females' reproductive status by sniffing their genitals, and maintained significantly closer proximity to females during their POPs, suggesting male mate guarding when conceptions are most likely to occur. Our findings indicate that the reproductive strategies of black howler central males and females coincide, highly skewing mating opportunities toward central males. Black howler females, however, occasionally choose to copulate with noncentral resident males or extra-group males during their POPs, undermining the ability of central males to monopolize all reproductive opportunities.

  17. Mating enhances the probability of winning aggressive encounters in male lobster cockroaches.

    PubMed

    Kou, Rong; Hsu, Chu-Chun

    2013-08-01

    In the present study, we report that contact with isolated female antenna significantly increases both the pheromone 3-hydroxy-2-butanone (3H-2B) release and the hemolymph JH III level in all examined aggressive posture-adopting (AP) and NP (non-AP-adopting) socially naïve males, with significantly faster concomitant pre-mating wing-raising behavior in AP as compared to NP males. 3H-2B release and JH III level were significantly increased after mating in both AP and NP males. A positive correlation was observed between mating experience and dominant status. Furthermore, mated-AP males initiated fights more rapidly and fought for a significantly longer duration than mated-NP males; retention with the paired female for 24h did not affect this increase. JH III level and 3H-2B release were significantly increased in dominant males as compared to subordinates. These results suggest that prior mating experience in invertebrates may enhance aggression in subsequent male-male encounters, with accompanying physiological (hormone and pheromone) responses.

  18. X-ray-induced sterility in Aedes albopictus (Diptera: Culicidae) and male longevity following irradiation.

    PubMed

    Yamada, H; Parker, A G; Oliva, C F; Balestrino, F; Gilles, J R L

    2014-07-01

    The mosquito Aedes albopictus (Skuse, 1895) is a potent vector of several arboviral diseases, most notably chikungunya and dengue fever. In the context of the sterile insect technique (SIT), the sterilization of the male mosquitoes before their release can be achieved by gamma-ray irradiation. As gamma-ray irradiators are becoming increasingly problematic to purchase and transport, the suitability of an X-ray irradiator as an alternative for the sterilization of Ae. albopictus males was studied. The sterilization of up to 200,000 pupae at one time can be achieved with relative ease, and the sterility results obtained were comparable with those achieved by gamma irradiation, where 99% sterility is induced with a dose of 40 Gy. A significant reduction of longevity was observed in the latter stages of the males' life after irradiation treatments, especially at doses > 40 Gy, which is consistent with the negative effects on longevity induced by similar radiation doses using gamma rays. Females irradiated at 40 Gy were not only 100% sterile, but also failed to oviposit entirely, i.e., all of the females laid 0 eggs. Overall, it was found that the X-ray irradiator is generally suitable for the sterilization process for sterile insect technique programs, as it showed a high processing capacity, practicality, high effectiveness, and reproducibility.

  19. Pest management programmes in vineyards using male mating disruption.

    PubMed

    Harari, Ally R; Zahavi, Tirtza; Gordon, Dvora; Anshelevich, Leonid; Harel, Miriam; Ovadia, Shmulik; Dunkelblum, Ezra

    2007-08-01

    Israeli vine growers have been reluctant to adopt the mating disruption technique for control of the European vine moth, Lobesia botrana Den. & Schiff. Since the chemically controlled honeydew moth, Cryptoblabes gnidiella Mill., coexists with the European vine moth, growers have maintained that the use of mating disruption would fail to bring about a significant reduction in pesticide use. In this study, the efficacy of mating disruption techniques against C. gnidiella was tested, as well as the effect of these methods on pesticide use and damage to clusters when the method was employed against both of the pests in wine grapes. Comparisons were made between plots treated with (1) L. botrana mating disruption pheromone, (2) L. botrana and C. gnidiella mating disruption pheromones and (3) control plots. A significant difference in the number of clusters infested with the developmental stages of the moths was seen between pheromone-treated plots and controls, while no such difference was observed between plots treated with one versus two pheromones. A similar pattern was observed in the number of insecticide applications; the greatest number of applications was used in control plots, followed by plots treated with L. botrana mating disruption pheromone and by plots treated with pheromones against both pests, in which no pesticides were applied.

  20. When not to copy: female fruit flies use sophisticated public information to avoid mated males

    PubMed Central

    Loyau, Adeline; Blanchet, Simon; Van Laere, Pauline; Clobert, Jean; Danchin, Etienne

    2012-01-01

    Semen limitation (lack of semen to fertilize all of a female's eggs) imposes high fitness costs to female partners. Females should therefore avoid mating with semen-limited males. This can be achieved by using public information extracted from watching individual males' previous copulating activities. This adaptive preference should be flexible given that semen limitation is temporary. We first demonstrate that the number of offspring produced by males Drosophila melanogaster gradually decreases over successive copulations. We then show that females avoid mating with males they just watched copulating and that visual public cues are sufficient to elicit this response. Finally, after males were given the time to replenish their sperm reserves, females did not avoid the males they previously saw copulating anymore. These results suggest that female fruit flies may have evolved sophisticated behavioural processes of resistance to semen-limited males, and demonstrate unsuspected adaptive context-dependent mate choice in an invertebrate. PMID:23105967

  1. When not to copy: female fruit flies use sophisticated public information to avoid mated males

    NASA Astrophysics Data System (ADS)

    Loyau, Adeline; Blanchet, Simon; van Laere, Pauline; Clobert, Jean; Danchin, Etienne

    2012-10-01

    Semen limitation (lack of semen to fertilize all of a female's eggs) imposes high fitness costs to female partners. Females should therefore avoid mating with semen-limited males. This can be achieved by using public information extracted from watching individual males' previous copulating activities. This adaptive preference should be flexible given that semen limitation is temporary. We first demonstrate that the number of offspring produced by males Drosophila melanogaster gradually decreases over successive copulations. We then show that females avoid mating with males they just watched copulating and that visual public cues are sufficient to elicit this response. Finally, after males were given the time to replenish their sperm reserves, females did not avoid the males they previously saw copulating anymore. These results suggest that female fruit flies may have evolved sophisticated behavioural processes of resistance to semen-limited males, and demonstrate unsuspected adaptive context-dependent mate choice in an invertebrate.

  2. Monitoring gene flow from transgenic sugar beet using cytoplasmic male-sterile bait plants.

    PubMed

    Saeglitz, C; Pohl, M; Bartsch, D

    2000-12-01

    One of the most discussed environmental effects associated with the use of transgenic plants is the flow of genes to plants in the environment. The flow of genes may occur through pollen since it is the reproductive system that is designed for gene movement. Pollen-mediated gene escape is hard to control in mating plants. Pollen from a wind pollinator can move over distances of more than 1000 m. To investigate the efficiency of transgenic pollen movement under realistic environmental conditions, the use of bait plants might be an effective tool. In this study, cytoplasmic male-sterile (CMS) sugar beets were tested with regard to their potential for monitoring transgene flow. As the pollen source, transgenic sugar beets were used that express recombinant DNA encoding viral (beet necrotic yellow vein virus) resistance, and antibiotic (kanamycin) and herbicide (glufosinate) tolerance genes. In a field trial, the effectiveness of a hemp (Cannabis sativa) stripe containment strategy was tested by measuring the frequency of pollinated CMS bait plants placed at different distances and directions from a transgenic pollen source. The results demonstrated the ineffectiveness of the containment strategy. Physiological and molecular tests confirmed the escape and production of transgenic offspring more than 200 m behind the hemp containment. Since absolute containment is unlikely to be effective, the CMS-bait plant detection system is a useful tool for other monitoring purposes.

  3. Indicators of recent mating success in the pipevine swallowtail butterfly (Battus philenor) and their relationship to male phenotype.

    PubMed

    Sasaki, Nayuta; Konagaya, Tatsuro; Watanabe, Mamoru; Rutowski, Ronald L

    2015-12-01

    A key determinant of the intensity of sexual selection acting on a trait is how variation in that trait is related to variance in reproductive success of individuals. This connection compels efforts to assess lifetime mating number and how it varies among individuals in a population. In the Lepidoptera, female mating success can be assessed relatively easily by counting by the number of spermatophores in the female's copulatory sac but male mating success in the field can often only be documented by observing copulations. Here we report a method for identifying whether or not males have recently mated that relies on the effect of mating on the appearance of the male's reproductive tract in the pipevine swallowtail, Battus philenor. In this species laboratory experiments reveal that during mating, components of a male's reproductive tract become shorter, decrease in mass, and change in appearance, irrespective of male age. These changes persist for at least two days after mating. After documenting these indicators of recent mating, we examined the reproductive tract of 68 field-caught males and found that twelve (17.6%) showed strong evidence of having mated recently. We found that older males were more likely to have recently mated. In addition, the color of the dorsal hindwing, a feature that females use in mate choice, was significantly greener in males, that according to our criteria, had recently-mated than in males that had not.

  4. Female mate preferences for male body size and shape promote sexual isolation in threespine sticklebacks

    PubMed Central

    Head, Megan L; Kozak, Genevieve M; Boughman, Janette W

    2013-01-01

    Female mate preferences for ecologically relevant traits may enhance natural selection, leading to rapid divergence. They may also forge a link between mate choice within species and sexual isolation between species. Here, we examine female mate preference for two ecologically important traits: body size and body shape. We measured female preferences within and between species of benthic, limnetic, and anadromous threespine sticklebacks (Gasterosteus aculeatus species complex). We found that mate preferences differed between species and between contexts (i.e., within vs. between species). Within species, anadromous females preferred males that were deep bodied for their size, benthic females preferred larger males (as measured by centroid size), and limnetic females preferred males that were more limnetic shaped. In heterospecific mating trials between benthics and limnetics, limnetic females continued to prefer males that were more limnetic like in shape when presented with benthic males. Benthic females showed no preferences for size when presented with limnetic males. These results show that females use ecologically relevant traits to select mates in all three species and that female preference has diverged between species. These results suggest that sexual selection may act in concert with natural selection on stickleback size and shape. Further, our results suggest that female preferences may track adaptation to local environments and contribute to sexual isolation between benthic and limnetic sticklebacks. PMID:23919161

  5. Paternity in wild ring‐tailed lemurs (Lemur catta): Implications for male mating strategies

    PubMed Central

    Sauther, Michelle L.; Cuozzo, Frank P.; Youssouf Jacky, Ibrahim Antho; Lawler, Richard R.; Sussman, Robert W.; Gould, Lisa; Pastorini, Jennifer

    2016-01-01

    1 In group‐living species with male dominance hierarchies where receptive periods of females do not overlap, high male reproductive skew would be predicted. However, the existence of female multiple mating and alternative male mating strategies can call into question single‐male monopolization of paternity in groups. Ring‐tailed lemurs (Lemur catta) are seasonally breeding primates that live in multi‐male, multi‐female groups. Although established groups show male dominance hierarchies, male dominance relationships can break down during mating periods. In addition, females are the dominant sex and mate with multiple males during estrus, including group residents, and extra‐group males—posing the question of whether there is high or low male paternity skew in groups. In this study, we analyzed paternity in a population of wild L. catta from the Bezà Mahafaly Special Reserve in southwestern Madagascar. Paternity was determined with 80–95% confidence for 39 offspring born to nine different groups. We calculated male reproductive skew indices for six groups, and our results showed a range of values corresponding to both high and low reproductive skew. Between 21% and 33% of offspring (3 of 14 or three of nine, counting paternity assignments at the 80% or 95% confidence levels, respectively) were sired by extra‐troop males. Males siring offspring within the same group during the same year appear to be unrelated. Our study provides evidence of varying male reproductive skew in different L. catta groups. A single male may monopolize paternity across one or more years, while in other groups, >1 male can sire offspring within the same group, even within a single year. Extra‐group mating is a viable strategy that can result in extra‐group paternity for L. catta males. PMID:27391113

  6. Transgenic induction of mitochondrial rearrangements for cytoplasmic male sterility in crop plants.

    PubMed

    Sandhu, Ajay Pal S; Abdelnoor, Ricardo V; Mackenzie, Sally A

    2007-02-06

    Stability of the mitochondrial genome is controlled by nuclear loci. In plants, nuclear genes suppress mitochondrial DNA rearrangements during development. One nuclear gene involved in this process is Msh1. Msh1 appears to be involved in the suppression of illegitimate recombination in plant mitochondria. To test the hypothesis that Msh1 disruption leads to the type of mitochondrial DNA rearrangements associated with naturally occurring cytoplasmic male sterility in plants, a transgenic approach for RNAi was used to modulate expression of Msh1 in tobacco and tomato. In both species, these experiments resulted in reproducible mitochondrial DNA rearrangements and a condition of male (pollen) sterility. The male sterility was, in each case, heritable, associated with normal female fertility, and apparently maternal in its inheritance. Segregation of the transgene did not reverse the male sterile phenotype, producing stable, nontransgenic male sterility. The reproducible transgenic induction of mitochondrial rearrangements in plants is unprecedented, providing a means to develop novel cytoplasmic male sterile lines for release as non-GMO or transgenic materials.

  7. Development, inheritance and breeding potential of a recessive genic male sterile line D248A in Sesame (Sesamum indicum L.).

    PubMed

    Liu, Hongyan; Yang, Minmin; Wu, Kun; Zhou, Xinan; Zhao, Yingzhong

    2013-01-01

    Genic male sterility (GMS) has great potential for heterosis exploitation in sesame (Sesamum indicum L.). Two spontaneous male-sterile plants were discovered in a Chinese sesame cultivar (Zhuzhi 4) in 2006. By consecutive sib mating with fertile plants from Zhuzhi 4, a new sterile line, D248A, was developed. Anatomy studies showed that D248A has thin, small and greenish anthers on which there are no or little pollen grains. The pollens are irregularly shaped and completely aborted, resulting in no germination and no formation of pollen tubes as revealed by acetocarmine stain or semi-solid suspension culture. Furthermore, D248A has a better performance in growth vigor, bloom duration and yield per plant than the other GMS lines (i.e. 95 ms-2A and 95 ms-5A). To investigate the inheritance mode of fertility, D248A was crossed and backcrossed with six varieties, and a segregating ratio of 3:1 and 1:1 for fertile and sterile plants was observed in F2 and BC1 populations, respectively. These results suggested that D248A is controlled by a recessive GMS gene. The average yield of four D248A-derived F1 hybrids is as high as 1695 kg·ha(-1), which is almost twice of that of 95 ms-5A-derived F1 hybrids. These results indicated that this newly developed recessive GMS line has great potential in sesame hybrid breeding.

  8. Effect of adult screwworm male size on mating competence

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Screwworms, Cochliomyia hominivorax (Coquerel) (Diptera: Calliphoridae), were devastating pests in parts of North America and Central America before their eradication by means of the sterile insect technique (SIT). Now, a barrier is maintained to prevent re-entry of screwworms from endemic regions t...

  9. Sexual conflict and the evolution of female mate choice and male social dominance.

    PubMed

    Moore, A J; Gowaty, P A; Wallin, W G; Moore, P J

    2001-03-07

    Conflicts between the sexes over control of reproduction are thought to lead to a cost of sexual selection through the evolution of male traits that manipulate female reproductive physiology and behaviour, and female traits that resist this manipulation. Although studies have begun to document negative fitness effects of sexual conflict, studies showing the expected association between sexual conflict and the specific behavioural mechanisms of sexual selection are lacking. Here we experimentally manipulated the opportunity for sexual conflict in the cockroach. Nauphoeta cinerea and showed that, for this species, odour cues in the social environment influence the behavioural strategies and fitness of males and females during sexual selection. Females provided with the opportunity for discriminating between males but not necessarily mating with preferred males produced fewer male offspring than females mated at random. The number of female offspring produced was not affected, nor was the viability of the offspring. Experimental modification of the composition of the males' pheromone showed that the fecundity effects were caused by exposure to the pheromone component that makes males attractive to females but also makes males less likely to be dominant. Female mate choice therefore carries a demographic cost but functions to avoid male manipulation and aggression. Male-male competition appears to function to circumvent mate choice rather than directly manipulating females, as the mate choice can be cryptic. The dynamic struggle between the sexes for control of mating opportunities and outcomes in N. cinerea therefore reveals a unique role for sexual conflict in the evolution of the behavioural components of sexual selection.

  10. Male mating rate is constrained by seminal fluid availability in bedbugs, Cimex lectularius.

    PubMed

    Reinhardt, Klaus; Naylor, Richard; Siva-Jothy, Michael T

    2011-01-01

    Sexual selection, differences in reproductive success between individuals, continues beyond acquiring a mating partner and affects ejaculate size and composition (sperm competition). Sperm and seminal fluid have very different roles in sperm competition but both components encompass production costs for the male. Theoretical models predict that males should spend ejaculate components prudently and differently for sperm and seminal fluid but empirical evidence for independent variation of sperm number and seminal fluid volume is scarce. It is also largely unknown how sperm and seminal fluid variation affect future mating rate. In bedbugs we developed a protocol to examine the role of seminal fluids in ejaculate allocation and its effect on future male mating rate. Using age-related changes in sperm and seminal fluid volume we estimated the lowest capacity at which mating activity started. We then showed that sexually active males allocate 12% of their sperm and 19% of their seminal fluid volume per mating and predicted that males would be depleted of seminal fluid but not of sperm. We tested (and confirmed) this prediction empirically. Finally, the slightly faster replenishment of seminal fluid compared to sperm did not outweigh the faster decrease during mating. Our results suggest that male mating rate can be constrained by the availability of seminal fluids. Our protocol might be applicable to a range of other organisms. We discuss the idea that economic considerations in sexual conflict research might benefit from distinguishing between costs and benefits that are ejaculate dose-dependent and those that are frequency-dependent on the mating rate per se.

  11. Male Mating Rate Is Constrained by Seminal Fluid Availability in Bedbugs, Cimex lectularius

    PubMed Central

    Reinhardt, Klaus; Naylor, Richard; Siva-Jothy, Michael T.

    2011-01-01

    Sexual selection, differences in reproductive success between individuals, continues beyond acquiring a mating partner and affects ejaculate size and composition (sperm competition). Sperm and seminal fluid have very different roles in sperm competition but both components encompass production costs for the male. Theoretical models predict that males should spend ejaculate components prudently and differently for sperm and seminal fluid but empirical evidence for independent variation of sperm number and seminal fluid volume is scarce. It is also largely unknown how sperm and seminal fluid variation affect future mating rate. In bedbugs we developed a protocol to examine the role of seminal fluids in ejaculate allocation and its effect on future male mating rate. Using age-related changes in sperm and seminal fluid volume we estimated the lowest capacity at which mating activity started. We then showed that sexually active males allocate 12% of their sperm and 19% of their seminal fluid volume per mating and predicted that males would be depleted of seminal fluid but not of sperm. We tested (and confirmed) this prediction empirically. Finally, the slightly faster replenishment of seminal fluid compared to sperm did not outweigh the faster decrease during mating. Our results suggest that male mating rate can be constrained by the availability of seminal fluids. Our protocol might be applicable to a range of other organisms. We discuss the idea that economic considerations in sexual conflict research might benefit from distinguishing between costs and benefits that are ejaculate dose-dependent and those that are frequency-dependent on the mating rate per se. PMID:21779378

  12. The sterile-male-release technique in Great Lakes sea lamprey management

    USGS Publications Warehouse

    Twohey, Michael B.; Heinrich, John W.; Seelye, James G.; Fredricks, Kim T.; Bergstedt, Roger A.; Kaye, Cheryl A.; Scholefield, Ron J.; McDonald, Rodney B.; Christie, Gavin C.

    2003-01-01

    The implementation of a sterile-male-release technique from 1991 through 1999 and evaluation of its effectiveness in the Great Lakes sea lamprey (Petromyzon marinus) management program is reviewed. Male sea lampreys were injected with the chemosterilant bisazir (P,P-bis(1-aziridinyl)-N-methylphosphinothioic amide) using a robotic device. Quality assurance testing indicated the device delivered a consistent and effective dose of bisazir. Viability of embryos in an untreated control group was 64% compared to 1% in a treatment group. A task force developed nine hypotheses to guide implementation and evaluation of the technique. An annual average of 26,000 male sea lampreys was harvested from as many as 17 Great Lakes tributaries for use in the technique. An annual average of 16,100 sterilized males was released into 33 tributaries of Lake Superior to achieve a theoretical 59% reduction in larval production during 1991 to 1996. The average number of sterile males released in the St. Marys River increased from 4,000 during 1991 to 1996 to 20,100 during 1997 to 1999. The theoretical reduc-stertion in reproduction when combined with trapping was 57% during 1991 to 1996 and 86% during 1997 to 1999. Evaluation studies demonstrated that sterilized males were competitive and reduced production of larvae in streams. Field studies and simulation models suggest reductions in reproduction will result in fewer recruits, but there is risk of periodic high recruitment events independent of sterile-male release. Strategies to reduce reproduction will be most reliable when low densities of reproducing females are achieved. Expansion of the technique is limited by access to additional males for sterilization. Sterile-male release and other alternative controls are important in delivering integrated pest management and in reducing reliance on pesticides.

  13. Female crickets assess relatedness during mate guarding and bias storage of sperm towards unrelated males.

    PubMed

    Tuni, C; Beveridge, M; Simmons, L W

    2013-06-01

    Recent evidence shows that females exert a post-copulatory fertilization bias in favour of unrelated males to avoid the genetic incompatibilities derived from inbreeding. One of the mechanisms suggested for fertilization biases in insects is female control over transport of sperm to the sperm-storage organs. We investigated post-copulatory inbreeding-avoidance mechanisms in females of the cricket Teleogryllus oceanicus. We assessed the relative contribution of related and unrelated males to the sperm stores of double-mated females. To demonstrate unequivocally that biased sperm storage results from female control rather than cryptic male choice, we manipulated the relatedness of mated males and of males performing post-copulatory mate guarding. Our results show that when guarded by a related male, females store less sperm from their actual mate, irrespective of the relatedness of the mating male. Our data support the notion that inhibition of sperm storage by female crickets can act as a form of cryptic female choice to avoid the severe negative effects of inbreeding.

  14. Courtship raises male fertilization success through post-mating sexual selection in a spider.

    PubMed

    Schneider, Jutta M; Lesmono, Kristiani

    2009-09-07

    Courtship is well known for its positive effects on mating success. However, in polyandrous species, sexual selection continues to operate after copulation. Cryptic female choice is expected under unpredictable mating rates in combination with sequential mate encounters. However, there are very few accounts of the effects of courtship on cryptic female choice, and the available evidence is often correlative. Mature Argiope bruennichi females are always receptive and never attack or reject males before mating, although sexual cannibalism after mating occurs regularly. Still, males usually perform an energetic vibratory display prior to copulation. We tested the hypothesis that beneficial effects of courtship arise cryptically, during or after mating, resulting in increased paternity success under polyandry. Manipulating courtship duration experimentally, we found that males that mated without display had a reduced paternity share even though no differences in post-copulatory cannibalism or copulation duration were detected. This suggests that the paternity advantage associated with courtship arose through female-mediated processes after intromission, meeting the definition of cryptic female choice.

  15. Alternative mating tactics in the yellow dung fly: resolving mechanisms of small-male advantage off pasture.

    PubMed

    Gress, Brian E; Waltzer, Ryan J; Lüpold, Stefan; Droge-Young, Elizabeth M; Manier, Mollie K; Pitnick, Scott

    2014-01-07

    Recent work suggests that the yellow dung fly mating system may include alternative patroller-competitor mating tactics in which large males compete for gravid females on dung, whereas small, non-competitive males search for females at foraging sites. Small males obtain most matings off pasture, yet the behavioural mechanism(s) giving rise to this pattern are unknown. We investigated the male and female behaviours that determine mating success in this environment by conducting field mating experiments and found small males to benefit from several attributes specific to the off-pasture mating environment. First, small males from foraging sites exhibited higher mating propensity, indicating that large males away from dung may be depleted of energy and/or sperm. Second, small males were more discriminating, being significantly less likely to attempt with non-gravid females, which are absent on dung but common off pasture. Third, non-gravid females were generally more likely to actively struggle and reject mating attempts; however, such behaviours occurred disproportionately more often with large males. Female Scathophaga stercoraria thus appear to preferentially mate with small males when off pasture. These findings challenge assumptions about male-female interactions in systems with alternative mating tactics and reveal hidden processes that may influence selection patterns in the field.

  16. Male Age Affects Female Mate Preference, Quantity of Accessory Gland Proteins, and Sperm Traits and Female Fitness in D. melanogaster.

    PubMed

    Rezaei, Abolhasan; Krishna, Mysore Siddaiah; Santhosh, Hassan T

    2015-01-01

    For species in which mating is resource-independent and offspring do not receive parental care, theoretical models of age-based female mate preference predict that females should prefer to mate with older males as they have demonstrated ability to survive. Thus, females should obtain a fitness benefit from mating with older males. However, male aging is often associated with reductions in quantity of sperm. The adaptive significance of age-based mate choice is therefore unclear. Various hypotheses have made conflicting predictions concerning this issue, because published studies have not investigated the effect of age on accessory gland proteins and sperm traits. D. melanogaster exhibits resource-independent mating, and offspring do not receive parental care, making this an appropriate model for studying age-based mate choice. In the present study, we found that D. melanogaster females of all ages preferred to mate with the younger of two competing males. Young males performed significantly greater courtship attempts and females showed least rejection for the same than middle-aged and old males. Young males had small accessory glands that contained very few main cells that were larger than average. Nevertheless, compared with middle-aged or old males, the young males transferred greater quantities of accessory gland proteins and sperm to mated females. As a result, females that mated with young male produced more eggs and progeny than those that mated with older males. Furthermore, mating with young male reduced female's lifespan. These studies indicate that quantity of accessory gland proteins and sperm traits decreased with male age and females obtain direct fitness benefit from mating with preferred young males.

  17. Molecular mapping of three male-sterile, female-fertile mutants and generation of a comprehensive map of all known male sterility genes in soybean.

    PubMed

    Yang, Yang; Speth, Benjamin D; Boonyoo, Napatsakorn; Baumert, Eric; Atkinson, Taylor R; Palmer, Reid G; Sandhu, Devinder

    2014-03-01

    In soybean, an environmentally stable male sterility system is vital for making hybrid seed production commercially viable. Eleven male-sterile, female-fertile mutants (ms1, ms2, ms3, ms4, ms5, ms6, ms7, ms8, ms9, msMOS, and msp) have been identified in soybean. Of these, eight (ms2, ms3, ms5, ms7, ms8, ms9, msMOS, and msp) have been mapped to soybean chromosomes. The objectives of this study were to (i) locate the ms1, ms4, and ms6 genes to soybean chromosomes; (ii) generate genetic linkage maps of the regions containing these genes; and (iii) develop a comprehensive map of all known male-sterile, female-fertile genes in soybean. The bulked segregant analysis technique was used to locate genes to soybean chromosomes. Microsatellite markers from the corresponding chromosomes were used on F2 populations to generate genetic linkage maps. The ms1 and ms6 genes were located on chromosome 13 (molecular linkage group F) and ms4 was present on chromosome 2 (molecular linkage group D1b). Molecular analyses revealed markers Satt516, BARCSOYSSR_02_1539, and AW186493 were located closest to ms1, ms4, and ms6, respectively. The ms1 and ms6 genes, although present on the same chromosome, were independently assorting with a genetic distance of 73.7 cM. Using information from this study and compiled information from previously published male sterility genes in soybean, a comprehensive genetic linkage map was generated. Eleven male sterility genes were present on seven soybean chromosomes. Four genes were present in two regions on chromosome 2 (molecular linkage group D1b) and two genes were present on chromosome 13 (molecular linkage group F).

  18. Neighboring genes for DNA-binding proteins rescue male sterility in Drosophila hybrids

    PubMed Central

    Liénard, Marjorie A.; Araripe, Luciana O.; Hartl, Daniel L.

    2016-01-01

    Crosses between closely related animal species often result in male hybrids that are sterile, and the molecular and functional basis of genetic factors for hybrid male sterility is of great interest. Here, we report a molecular and functional analysis of HMS1, a region of 9.2 kb in chromosome 3 of Drosophila mauritiana, which results in virtually complete hybrid male sterility when homozygous in the genetic background of sibling species Drosophila simulans. The HMS1 region contains two strong candidate genes for the genetic incompatibility, agt and Taf1. Both encode unrelated DNA-binding proteins, agt for an alkyl-cysteine-S-alkyltransferase and Taf1 for a subunit of transcription factor TFIID that serves as a multifunctional transcriptional regulator. The contribution of each gene to hybrid male sterility was assessed by means of germ-line transformation, with constructs containing complete agt and Taf1 genomic sequences as well as various chimeric constructs. Both agt and Taf1 contribute about equally to HMS1 hybrid male sterility. Transgenes containing either locus rescue sterility in about one-half of the males, and among fertile males the number of offspring is in the normal range. This finding suggests compensatory proliferation of the rescued, nondysfunctional germ cells. Results with chimeric transgenes imply that the hybrid incompatibilities result from interactions among nucleotide differences residing along both agt and Taf1. Our results challenge a number of preliminary generalizations about the molecular and functional basis of hybrid male sterility, and strongly reinforce the role of DNA-binding proteins as a class of genes contributing to the maintenance of postzygotic reproductive isolation. PMID:27357670

  19. Male topi antelopes alarm snort deceptively to retain females for mating.

    PubMed

    Bro-Jørgensen, Jakob; Pangle, Wiline M

    2010-07-01

    Despite intense interest in the role of deception in animal communication, empirical evidence is wanting that nonhuman animals are capable of actively falsifying signals to manipulate mates for reproductive benefits. Tactical use of false positive signals has thus been documented mainly where interests are consistently opposed, such as between predator and prey and between competitors for food and for mates. Here we report that male topi antelopes alarm snort deceptively to retain receptive females in their territories and thereby secure mating opportunities. The finding reveals that sexual conflict over mating, which is known to promote various forms of coercion and sensory bias exploitation, can also lead to active signal falsification. However, because honesty in sexual signals is generally assured by physical or cost-enforced constraints on signal production, sexually selected mate deception is likely to target mainly signals, such as alarm calls, that were originally not under sexual selection.

  20. Two aromatase inhibitors inhibit the ability of a third to promote mating in male rats.

    PubMed

    Yahr, Pauline

    2015-09-01

    Aromatase, the enzyme that aromatizes androstenedione (A) to estrone and testosterone (T) to estradiol (E), affects androgen control of male sex behavior in many vertebrates. In male monkeys, rats and quail, E mimics the ability of T to promote mating, and aromatase inhibitors block mating induced by T but not E. Aromatase inhibitors include androgens with different A-rings than T and A, e.g., 1,4,6-androstatriene-3,17-dione (ATD), azoles, e.g., fadrozole, and androgens α-halogenated at carbon 6, e.g., 6α-bromoA, 6α-fluoroA and 6α-fluoroT. 6α-FluoroT is the only 6α-halogenated androgen studied in regard to mating. It promotes mating in male rats and quail and was studied, before it was known to inhibit aromatase, because it cannot be aromatized yet has the same A-ring as T. 6α-FluoroT might promote mating by binding estrogen receptors (ER) directly, i.e., unassisted, or by metabolism to an androgen that binds ER. Since neither process would require aromatase, this study tested both hypotheses by determining how mating induced in castrated male rats by 6α-fluoroT is affected by ATD and fadrozole. Both aromatase inhibitors inhibited the effects of 6α-fluoroT on mating. Thus, 6α-fluoroT does not promote mating by direct ER binding or metabolism to another androgen. Since aromatase underlies a process in which 6α-fluoroT, unlike most nonaromatizable androgens, mimics T effects on male sex behavior, the process must involve a feature that 6α-fluoroT shares with T but not other nonaromatizable androgens. A-ring structure is a candidate. A hypothesis is also offered for how aromatase may participate without aromatizing the androgen.

  1. Alternative mating tactics in the yellow dung fly: resolving mechanisms of small-male advantage off pasture

    PubMed Central

    Gress, Brian E.; Waltzer, Ryan J.; Lüpold, Stefan; Droge-Young, Elizabeth M.; Manier, Mollie K.; Pitnick, Scott

    2014-01-01

    Recent work suggests that the yellow dung fly mating system may include alternative patroller–competitor mating tactics in which large males compete for gravid females on dung, whereas small, non-competitive males search for females at foraging sites. Small males obtain most matings off pasture, yet the behavioural mechanism(s) giving rise to this pattern are unknown. We investigated the male and female behaviours that determine mating success in this environment by conducting field mating experiments and found small males to benefit from several attributes specific to the off-pasture mating environment. First, small males from foraging sites exhibited higher mating propensity, indicating that large males away from dung may be depleted of energy and/or sperm. Second, small males were more discriminating, being significantly less likely to attempt with non-gravid females, which are absent on dung but common off pasture. Third, non-gravid females were generally more likely to actively struggle and reject mating attempts; however, such behaviours occurred disproportionately more often with large males. Female Scathophaga stercoraria thus appear to preferentially mate with small males when off pasture. These findings challenge assumptions about male–female interactions in systems with alternative mating tactics and reveal hidden processes that may influence selection patterns in the field. PMID:24225455

  2. Egg Viability, Mating Frequency and Male Mating Ability Evolve in Populations of Drosophila melanogaster Selected for Resistance to Cold Shock

    PubMed Central

    Singh, Karan; Kochar, Ekta; Prasad, N. G.

    2015-01-01

    Background Ability to resist temperature shock is an important component of fitness of insects and other ectotherms. Increased resistance to temperature shock is known to affect life-history traits. Temperature shock is also known to affect reproductive traits such as mating ability and viability of gametes. Therefore selection for increased temperature shock resistance can affect the evolution of reproductive traits. Methods We selected replicate populations of Drosophila melanogaster for resistance to cold shock. We then investigated the evolution of reproductive behavior along with other components of fitness- larval survivorship, adult mortality, fecundity, egg viability in these populations. Results We found that larval survivorship, adult mortality and fecundity post cold shock were not significantly different between selected and control populations. However, compared to the control populations, the selected populations laid significantly higher percentage of fertile eggs (egg viability) 24 hours post cold shock. The selected populations had higher mating frequency both with and without cold shock. After being subjected to cold shock, males from the selected populations successfully mated with significantly more non-virgin females and sired significantly more progeny compared to control males. Conclusions A number of studies have reported the evolution of survivorship in response to selection for temperature shock resistance. Our results clearly indicate that adaptation to cold shock can involve changes in components of reproductive fitness. Our results have important implications for our understanding of how reproductive behavior can evolve in response to thermal stress. PMID:26065704

  3. Retention of Ejaculate by Drosophila melanogaster Females Requires the Male-Derived Mating Plug Protein PEBme

    PubMed Central

    Avila, Frank W.; Cohen, Allie B.; Ameerudeen, Fatima S.; Duneau, David; Suresh, Shruthi; Mattei, Alexandra L.; Wolfner, Mariana F.

    2015-01-01

    Within the mated reproductive tracts of females of many taxa, seminal fluid proteins (SFPs) coagulate into a structure known as the mating plug (MP). MPs have diverse roles, including preventing female remating, altering female receptivity postmating, and being necessary for mated females to successfully store sperm. The Drosophila melanogaster MP, which is maintained in the mated female for several hours postmating, is comprised of a posterior MP (PMP) that forms quickly after mating begins and an anterior MP (AMP) that forms later. The PMP is composed of seminal proteins from the ejaculatory bulb (EB) of the male reproductive tract. To examine the role of the PMP protein PEBme in D. melanogaster reproduction, we identified an EB GAL4 driver and used it to target PEBme for RNA interference (RNAi) knockdown. PEBme knockdown in males compromised PMP coagulation in their mates and resulted in a significant reduction in female fertility, adversely affecting postmating uterine conformation, sperm storage, mating refractoriness, egg laying, and progeny generation. These defects resulted from the inability of females to retain the ejaculate in their reproductive tracts after mating. The uncoagulated MP impaired uncoupling by the knockdown male, and when he ultimately uncoupled, the ejaculate was often pulled out of the female. Thus, PEBme and MP coagulation are required for optimal fertility in D. melanogaster. Given the importance of the PMP for fertility, we identified additional MP proteins by mass spectrometry and found fertility functions for two of them. Our results highlight the importance of the MP and the proteins that comprise it in reproduction and suggest that in Drosophila the PMP is required to retain the ejaculate within the female reproductive tract, ensuring the storage of sperm by mated females. PMID:26058847

  4. Retention of Ejaculate by Drosophila melanogaster Females Requires the Male-Derived Mating Plug Protein PEBme.

    PubMed

    Avila, Frank W; Cohen, Allie B; Ameerudeen, Fatima S; Duneau, David; Suresh, Shruthi; Mattei, Alexandra L; Wolfner, Mariana F

    2015-08-01

    Within the mated reproductive tracts of females of many taxa, seminal fluid proteins (SFPs) coagulate into a structure known as the mating plug (MP). MPs have diverse roles, including preventing female remating, altering female receptivity postmating, and being necessary for mated females to successfully store sperm. The Drosophila melanogaster MP, which is maintained in the mated female for several hours postmating, is comprised of a posterior MP (PMP) that forms quickly after mating begins and an anterior MP (AMP) that forms later. The PMP is composed of seminal proteins from the ejaculatory bulb (EB) of the male reproductive tract. To examine the role of the PMP protein PEBme in D. melanogaster reproduction, we identified an EB GAL4 driver and used it to target PEBme for RNA interference (RNAi) knockdown. PEBme knockdown in males compromised PMP coagulation in their mates and resulted in a significant reduction in female fertility, adversely affecting postmating uterine conformation, sperm storage, mating refractoriness, egg laying, and progeny generation. These defects resulted from the inability of females to retain the ejaculate in their reproductive tracts after mating. The uncoagulated MP impaired uncoupling by the knockdown male, and when he ultimately uncoupled, the ejaculate was often pulled out of the female. Thus, PEBme and MP coagulation are required for optimal fertility in D. melanogaster. Given the importance of the PMP for fertility, we identified additional MP proteins by mass spectrometry and found fertility functions for two of them. Our results highlight the importance of the MP and the proteins that comprise it in reproduction and suggest that in Drosophila the PMP is required to retain the ejaculate within the female reproductive tract, ensuring the storage of sperm by mated females.

  5. Male Texas Horned Lizards increase daily movements and area covered in spring: A mate searching strategy?

    USGS Publications Warehouse

    Stark, Richard C.; Fox, S. F.; David, M.L.

    2005-01-01

    Texas Horned Lizards, Phrynosoma cornutum, were tracked using fluorescent powder to determine exact daily movements. Daily linear movements and daily space use were compared between adult males and females. Lizards that traveled the greatest linear distances also covered the largest areas. In Oklahoma, adults emerge from hibernation in late April and early May and mate soon afterward. Males traveled significantly greater distances (and covered significantly larger areas in a day) than females in May but not after May. We propose that males move more and cover more area than females early in the mating season to intercept receptive females. Copyright 2005 Society for the Study of Amphibians and Reptiles.

  6. Two recessive genes controlling thermophotoperiod-sensitive male sterility in wheat.

    PubMed

    Guo, R X; Sun, D F; Tan, Z B; Rong, D F; Li, C D

    2006-05-01

    Male sterility of wheat-breeding line 337S (Triticum aestivum L.) is sensitive to both short day-length/low temperature and long day-length/high temperature. 337S was crossed with the common wheat variety, Huamai No. 8 and the F1 was highly fertile. The F2 population segregated in a 15:1 ratio for fertility/sterility in 243 individuals under long day-length/high-temperature. The two thermophotoperiod-responsive male sterile genes were mapped to chromosomes 5B and 2B using Simple Sequence Repeat (SSR) markers and bulked segregant analysis. Partial linkage maps around the sterility loci of chromosomes 2B and 5B were constructed using the 243 individuals in the F2 population. One gene (wptms1) for male sterility was flanked by the SSR markers Xgwm335 and Xgwm371 at a genetic distance in chromosome 5B of 4.1 and 24.4 cM, respectively. The second gene (wptms2) was mapped between markers Xgwm374 and Xgwm120 at a genetic distance of 6.6 and 20.9 cM, respectively. The closest linked markers Xgwm335 (wptms1) and Xgwm374 (wptms2) explained 53 and 38% of phenotypic variation for the fertility. The SSR markers provide a useful tool to transfer the male sterile genes into elite wheat germplasm.

  7. Genome-wide misexpression of X-linked versus autosomal genes associated with hybrid male sterility.

    PubMed

    Lu, Xuemei; Shapiro, Joshua A; Ting, Chau-Ti; Li, Yan; Li, Chunyan; Xu, Jin; Huang, Huanwei; Cheng, Ya-Jen; Greenberg, Anthony J; Li, Shou-Hsien; Wu, Mao-Lien; Shen, Yang; Wu, Chung-I

    2010-08-01

    Postmating reproductive isolation is often manifested as hybrid male sterility, for which X-linked genes are overrepresented (the so-called large X effect). In contrast, X-linked genes are significantly under-represented among testis-expressing genes. This seeming contradiction may be germane to the X:autosome imbalance hypothesis on hybrid sterility, in which the X-linked effect is mediated mainly through the misexpression of autosomal genes. In this study, we compared gene expression in fertile and sterile males in the hybrids between two Drosophila species. These hybrid males differ only in a small region of the X chromosome containing the Ods-site homeobox (OdsH) (also known as Odysseus) locus of hybrid sterility. Of genes expressed in the testis, autosomal genes were, indeed, more likely to be misexpressed than X-linked genes under the sterilizing action of OdsH. Since this mechanism of X:autosome interaction is only associated with spermatogenesis, a connection between X:autosome imbalance and the high rate of hybrid male sterility seems plausible.

  8. Sterilization.

    PubMed

    Rioux, M H

    1979-05-01

    The history of sterilization in North America has included enactment of laws in 37 U. S. states and 2 Canadian provinces allowing the procedure to be performed to eliminate undesirable, genetically-transmitted traits. These eugenic laws applied to any of the following categories of persons: mentally regarded, mentally ill, epileptic, criminal, alcoholic, or poor people. Pressure from geneticists, lawyers, and others concerned with the implications of such laws, led to their repeal in many places. Noneugenic and nontherapeutic sterilization is today a recognized medical practice. Legally, such procedures must meet the following criteria: 1) informed consent; 2) individual benefit; and 3) performance with reasonable care and skill. If these criteria are met, doctors are protected from legal liability. The most legal, social, and ethical ambiguities arise in cases where nontherapeutic sterilization is performed on individuals unable to give consent, e.g., minors or mentally handicapped persons.

  9. Interdependent effects of male and female body size plasticity on mating behaviour of predatory mites

    PubMed Central

    Walzer, Andreas; Schausberger, Peter

    2015-01-01

    The adaptive canalization hypothesis predicts that traits with low phenotypic plasticity are more fitness relevant, because they have been canalized via strong past selection, than traits with high phenotypic plasticity. Based on differing male body size plasticities of the predatory mites Phytoseiulus persimilis (low plasticity) and Neoseiulus californicus (high plasticity), we accordingly hypothesized that small male body size entails higher costs in female choice and male–male competition in P. persimilis than N. californicus. Males of both species are highly polygynous but females differ in the level of polyandry (low level in P. persimilis; medium level in N. californicus). We videotaped the mating interactions in triplets of either P. persimilis or N. californicus, consisting of a virgin female (small or standard-sized) and a small and a standard-sized male. Mating by both small and standard-sized P. persimilis females was biased towards standard-sized males, resulting from the interplay between female preference for standard-sized males and the inferiority of small males in male–male competition. In contrast, mating by N. californicus females was equally balanced between small and standard-sized males. Small N. californicus males were more aggressive (‘Napoleon complex’) in male–male competition, reducing the likelihood of encounter between the standard-sized male and the female, and thus counterbalancing female preference for standard-sized males. Our results support the hypothesis that male body size is more important to fitness in the low-level polyandrous P. persimilis than in the medium-level polyandrous N. californicus and provide a key example of the implications of sexually selected body size plasticity on mating behaviour. PMID:25673881

  10. Exposure to tea tree oil enhances the mating success of male Mediterranean fruit flies (Diptera: Tephritidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aroma of various plant essential oils has been shown to enhance the mating competitiveness of males of the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann). Laboratory observations revealed that male medflies show strong short-range attraction to tea tree oil (TTO hereafter) deri...

  11. Male Enchenopa treehoppers (Hemiptera: Membracidae) vary mate-searching behavior but not signaling behavior in response to spider silk

    NASA Astrophysics Data System (ADS)

    Fowler-Finn, Kasey D.; Al-Wathiqui, Nooria; Cruz, Daniel; Al-Wathiqui, Mishal; Rodríguez, Rafael L.

    2014-03-01

    Finding and attracting mates can impose costs on males in terms of increased encounters with, and attraction of, predators. To decrease the likelihood of predation, males may modify mate-acquisition efforts in two main ways: they may reduce mate-searching efforts or they may reduce mate-attraction efforts. The specific behavior that males change in the presence of predator cues should depend upon the nature of risk imposed by the type of predator present in the environment. For example, sit-and-wait predators impose greater costs to males moving in search of mates. Here, we test whether cues of the presence of a sit-and-wait predator lead to a reduction in mate-searching but not mate-acquisition behavior. We used a member of the Enchenopa binotata complex of treehoppers—a clade of vibrationally communicating insects in which males fly in search of mates and produce mate-attraction signals when they land on plant stems. We tested for changes in mate-searching and signaling behaviors when silk from a web-building spider was present or absent. We found that males delayed flight when spider silk was present but only if they were actively searching for mates. These results suggest that males have been selected to reduce predation risk by adjusting how they move about their environment according to the cues of sit-and-wait predators.

  12. Male mate choice, sexual conflict and strategic allocation of copulations in a lekking bird.

    PubMed Central

    Saether, S. A.; Fiske, P.; Kålås, J. A.

    2001-01-01

    The males of lekking species are not expected to be choosy about mating because a reduced reproductive rate due to lost mating opportunities should outweigh any benefits of male choice. Females have traditionally not been expected to be competitive in this system since their reproduction has usually been assumed to be unconstrained by male availability. Here we show that, in contrast to these predictions, males are choosy and females may be competitive in the lekking great snipe Gallinago media. Males preferred by many females often refused to copulate with and even chased away females that the male had already copulated with, whereas females seemed to compete for repeated copulations. We conclude that choosiness may sometimes pay for popular males in those lekking species where females copulate repeatedly. Apparently, evolutionary conflicts of interest between individuals may cause a richer repertoire of behavioural adaptations than, to our knowledge, hitherto realized. PMID:11600073

  13. Methoprene and protein supplements accelerate reproductive development and improve mating success of male tephritid flies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have been studying the physiological mechanisms responsible for coordination of reproductive maturity and sex pheromone communication in males of tephritid flies in order to develop methods for acceleration of reproductive maturity among sterilized males. Our studies revealed that the juvenile ho...

  14. Mating success of resident versus non-resident males in a territorial butterfly

    PubMed Central

    Bergman, Martin; Gotthard, Karl; Berger, David; Olofsson, Martin; Kemp, Darrell J; Wiklund, Christer

    2007-01-01

    Male–male competition over territorial ownership suggests that winning is associated with considerable benefits. In the speckled wood butterfly, Pararge aegeria, males fight over sunspot territories on the forest floor; winners gain sole residency of a sunspot, whereas losers patrol the forest in search of females. It is currently not known whether residents experience greater mating success than non-residents, or whether mating success is contingent on environmental conditions. Here we performed an experiment in which virgin females of P. aegeria were allowed to choose between a resident and a non-resident male in a large enclosure containing one territorial sunspot. Resident males achieved approximately twice as many matings as non-residents, primarily because matings were most often preceded by a female being discovered when flying through a sunspot. There was no evidence that territorial residents were more attractive per se, with females seen to reject them as often as non-residents. Furthermore, in the cases where females were discovered outside of the sunspot, they were just as likely to mate with non-residents as residents. We hypothesize that the proximate advantage of territory ownership is that light conditions in a large sunspot greatly increase the male's ability to detect and intercept passing receptive females. PMID:17472909

  15. Male heroin addicts and their female mates: impact on disorder and recovery.

    PubMed

    Lex, B W

    1990-01-01

    A pilot investigation was undertaken to determine whether the social relationships between men who currently used heroin with their female mates differed from those of men who formerly used heroin, but were currently abstinent, with their female mates. Six couples were selected for study via the representative case method. Men currently abstinent from heroin had begun drug use later, had a family history of affective disorders, and had initiated their conjugal relationship after cessation of heroin use. Female mates of males currently abstinent from heroin had never used heroin with their mates in conjunction with sexual activity, had significantly positive ratings of their mates' performance of social roles, and were striving to obtain formal training to improve their employment skills. In contrast, the couples including actively using heroin addicts used opiates together, especially to enhance their sexual activity. The relationships of these couples were not as mutually supportive, and the male's role was less responsible and attracted less respect than that of the abstinent male. The females were depressed and had little positive aspects to their lives. Partners in all couples experienced a large number of stressful events, but current heroin use increased stress and hampered coping efforts. Interaction analysis of dynamics in relationships of men currently abstinent from heroin revealed that participation in mates' family life served to reshape their behaviors into more socially acceptable roles.

  16. Heterozygous alleles restore male fertility to cytoplasmic male-sterile radish (Raphanus sativus L.): a case of overdominance.

    PubMed

    Wang, Zhi Wei; De Wang, Chuan; Wang, Chuan; Gao, Lei; Mei, Shi Yong; Zhou, Yuan; Xiang, Chang Ping; Wang, Ting

    2013-04-01

    The practice of hybridization has greatly contributed to the increase in crop productivity. A major component that exploits heterosis in crops is the cytoplasmic male sterility (CMS)/nucleus-controlled fertility restoration (Rf) system. Through positional cloning, it is shown that heterozygous alleles (RsRf3-1/RsRf3-2) encoding pentatricopeptide repeat (PPR) proteins are responsible for restoring fertility to cytoplasmic male-sterile radish (Raphanus sativus L.). Furthermore, it was found that heterozygous alleles (RsRf3-1/RsRf3-2) show higher expression and RNA polymerase II occupancy in the CMS cytoplasmic background compared with their homozygous alleles (RsRf3-1/RsRf3-1 or RsRf3-2/RsRf3-2). These data provide new insights into the molecular mechanism of fertility restoration to cytoplasmic male-sterile plants and illustrate a case of overdominance.

  17. Meiotic sex chromosome inactivation is disrupted in sterile hybrid male house mice.

    PubMed

    Campbell, Polly; Good, Jeffrey M; Nachman, Michael W

    2013-03-01

    In male mammals, the X and Y chromosomes are transcriptionally silenced in primary spermatocytes by meiotic sex chromosome inactivation (MSCI) and remain repressed for the duration of spermatogenesis. Here, we test the longstanding hypothesis that disrupted MSCI might contribute to the preferential sterility of heterogametic hybrid males. We studied a cross between wild-derived inbred strains of Mus musculus musculus and M. m. domesticus in which sterility is asymmetric: F1 males with a M. m. musculus mother are sterile or nearly so while F1 males with a M. m. domesticus mother are normal. In previous work, we discovered widespread overexpression of X-linked genes in the testes of sterile but not fertile F1 males. Here, we ask whether this overexpression is specifically a result of disrupted MSCI. To do this, we isolated cells from different stages of spermatogenesis and measured the expression of several genes using quantitative PCR. We found that X overexpression in sterile F1 primary spermatocytes is coincident with the onset of MSCI and persists in postmeiotic spermatids. Using a series of recombinant X genotypes, we then asked whether X overexpression in hybrids is controlled by cis-acting loci across the X chromosome. We found that it is not. Instead, one large interval in the proximal portion of the M. m. musculus X chromosome is associated with both overexpression and the severity of sterility phenotypes in hybrids. These results demonstrate a strong association between X-linked hybrid male sterility and disruption of MSCI and suggest that trans-acting loci on the X are important for the transcriptional regulation of the X chromosome during spermatogenesis.

  18. Molecular-aided selection of male sterility for hybrid development in onion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maintainer lines are used to seed propagate male-sterile lines for the development of hybrid-onion cultivars. Selection of maintainer lines is more efficient using molecular markers that distinguish cytoplasms and genotypes at the nuclear male-fertility restoration (Ms) locus. Onion cytoplasms can b...

  19. Testosterone positively associated with both male mating effort and paternal behavior in Savanna baboons (Papio cynocephalus).

    PubMed

    Onyango, Patrick Ogola; Gesquiere, Laurence R; Altmann, Jeanne; Alberts, Susan C

    2013-03-01

    Testosterone (T) is often positively associated with male sexual behavior and negatively associated with paternal care. These associations have primarily been demonstrated in species where investment in paternal care begins well after mating activity is complete, when offspring are hatched or born. Different patterns may emerge in studies of species where investment in mating and paternal care overlap temporally, for instance in non-seasonal breeders in which males mate with multiple females sequentially and may simultaneously have multiple offspring of different ages. In a 9-year data set on levels of T in male baboons, fecal concentrations of T (fT) were positively associated with both mate guarding ("consortship") - a measure of current reproductive activity - and with the number of immature offspring a male had in his social group - a measure of past reproductive activity and an indicator of likely paternal behavior. To further examine the relationship between T and potential paternal behavior, we next drew on an intensive 8-month study of male behavior, and found that fathers were more likely to be in close proximity to their offspring than expected by chance. Because male baboons are known to provide paternal care, and because time in proximity to offspring would facilitate such care, this suggests that T concentrations in wild male baboons may be associated with both current reproductive activity and with current paternal behavior. These results are consistent with the predicted positive association between T and mating effort but not with a negative association between T and paternal care; in male baboons, high levels of T occur in males that are differentially associating with their offspring.

  20. GnRH-mediated olfactory and visual inputs promote mating-like behaviors in male zebrafish

    PubMed Central

    Li, Lei; Malin, John H.; Huang, Tao; Lee, Eric B.; Chen, Zijiang

    2017-01-01

    The engagement of sexual behaviors is regulated by a number of factors which include gene expression, hormone circulation, and multi-sensory information integration. In zebrafish, when a male and a female are placed in the same container, they show mating-like behaviors regardless of whether they are kept together or separated by a net. No mating-like behaviors are observed when same-sex animals are put together. Through the olfacto-visual centrifugal pathway, activation of the terminalis nerve in the olfactory bulb increases GnRH signaling in the brain and triggers mating-like behaviors between males. In zebrafish mutants or wild-type fish in which the olfacto-visual centrifugal pathway is impaired or chemically ablated, in response to odor stimulation the mating-like behaviors between males are no longer evident. Together, the data suggest that the combination of olfactory and visual signals alter male zebrafish's mating-like behaviors via GnRH signaling. PMID:28329004

  1. Release of thiotepa sterilized males into caged populations of Aedes aegypti: life table analysis.

    PubMed

    Gato, René; Companioni, Ariamys; Bruzón, Rosa Y; Menéndez, Zulema; González, Aileen; Rodríguez, Misladys

    2014-04-01

    Successful SIT trials against mosquitoes in the 1960-70s were achieved by sterilizing male mosquitoes using chemosterilants. Their use was discontinued after concerns were raised about the effect of residues on non-target organisms, although scant evidence has been published. Irradiation is an expensive process; chemosterilization could be an affordable option for implementing SIT programs in developing countries. We compare life table parameters of three Aedes aegypti populations comprising different ratios of thiotepa-treated and non-treated males in order to identify the impact on reproductive potential of the presence of sterile males. No difference was observed in the survival of the treated and untreated males. The release of thiotepa sterilized males into caged Ae. aegypti populations had no effect on death or survival probability of the individuals in the cages but the fecundity of females was significantly reduced, as evaluated by hatch rate and stable age structure parameters. The significant decreases in net reproduction rate, finite rate of natural increase and intrinsic rate of natural increase in populations including sterile males are sufficient to indicate that such populations would not be able to proliferate in natural conditions. This suggests that release of Ae. aegypti thiotepa-treated males could be effective in reducing the reproductive capability of the target population and consequently contribute to vector control.

  2. Behavioural effect of low-dose BPA on male zebrafish: Tuning of male mating competition and female mating preference during courtship process.

    PubMed

    Li, Xiang; Guo, Jia-Yu; Li, Xu; Zhou, Hai-Jun; Zhang, Shu-Hui; Liu, Xiao-Dong; Chen, Dong-Yan; Fang, Yong-Chun; Feng, Xi-Zeng

    2017-02-01

    The ubiquity of environmental pollution by endocrine disrupting chemicals (EDCs) such as bisphenol A (BPA) is progressively considered as a major threat to aquatic ecosystems worldwide. Numerous toxicological studies have proved that BPA are hazardous to aquatic environment, along with alterations in the development and physiology of aquatic vertebrates. However, generally, there is a paucity in knowledge of behavioural and physiological effects of BPA with low concentration, for example, 0.22 nM (50 ng/L) and 2.2 nM (500 ng/L). Here we show that treatment of adult male zebrafish (Danio rerio) with 7 weeks low-dose (0.22 nM-2.2 nM) BPA, resulted in alteration in histological structure of testis tissue and abnormality in expression levels of genes involved in testicular steroidogenesis. Furthermore, low-dose BPA treatment decreased the male locomotion during courtship; and was associated with less courtship behaviours to female but more aggressive behaviours to mating competitor. Interestingly, during the courtship test, we observed that female preferred control male to male under low-dose BPA exposure. Subsequently, we found that the ability of female to chose optimal mating male through socially mutual interaction and dynamics of male zebrafish, which was based on visual discrimination. In sum, our results shed light on the potential behavioural and physiological effect of low-dose BPA exposure on courtship behaviours of zebrafish, which could exert profound consequences on natural zebrafish populations.

  3. The influence of female age on male mating preference and reproductive success in cabbage beetle, Colaphellus bowringi.

    PubMed

    Liu, Xing-Ping; He, Hai-Min; Xue, Fang-Sen

    2014-08-01

    The influence of female age on male mating preference and reproductive success has been studied using a promiscuous cabbage beetle, Colaphellus bowringi Baly (Coleoptera: Chrysomelidae). In a simultaneous choice test, middle-aged females had significantly greater mating success than young and old females. In single pair trials, when paired with middle-aged virgin males, middle-aged females mated faster, copulated longer, and had greater fecundity and fertility than young or old females, while the longevity of males was not significantly affected by female age. This study on C. bowringi suggests that middle-aged females are more receptive to mating, which can result in the highest male reproductive success.

  4. The male blue crab, Callinectes sapidus, uses both chromatic and achromatic cues during mate choice.

    PubMed

    Baldwin, Jamie; Johnsen, Sönke

    2012-04-01

    In the blue crab, Callinectes sapidus, claw color varies by sex, sexual maturity and individual. Males rely in part on color cues to select appropriate mates, and these chromatic cues may be perceived through an opponent interaction between two photoreceptors with maximum wavelength sensitivities at 440 and 508 nm. The range of color discrimination of this dichromatic visual system may be limited, however, and it is unclear whether male blue crabs are capable of discriminating the natural variations in claw color that may be important in mate choice. By testing males' innate color preferences in binary choice tests between photographs of red-clawed females and six variations of orange-clawed females, we examined both the chromatic (opponent interaction) and achromatic (relative luminance) cues used in male mate choice. Males significantly preferred red-clawed females to orange-clawed females, except when the test colors were similar in both opponency and relative luminance. Our results are unusual in that they indicate that male mate choice in the blue crab is not guided solely by achromatic or chromatic mechanisms, suggesting that both color and intensity are used to evaluate female claw color.

  5. Reduced mate preference for dominant over subordinate males in old female Syrian hamsters (Mesocricetus auratus).

    PubMed

    Place, Ned J; Vernon, Dianne M; Johnston, Robert E

    2014-10-01

    Why some females choose to mate with a 'preferred' male, whereas others choose to mate with an 'inferior' male is not always clear. Generally, the choosiness of females is thought to decline with advanced age, but relatively few studies have investigated this concept, and reports of this phenomenon in mammals are lacking. To address this deficiency, young and old female golden hamsters were evaluated for their preference for dominant vs. subordinate males. Females observed male dyads as a dominance relationship was established. Dominant and subordinate males were then placed within enclosures at the opposite ends of a Y-maze, and the first approach, scent marking, and time spent near each male were evaluated in young and old females during pro-oestrus-a time when females solicit visits by prospective mates by leaving vaginal and flank scent marks. Whereas the proportion of time spent near the dominant male was significantly greater than random for both young and old females, the proportions of vaginal and flank scent marks left for the dominant male were significantly greater than random for young females, but not for old females. Overall, these results are consistent with a decline in the preference for dominant males by old female hamsters.

  6. Inbreeding depresses sperm competitiveness, but not fertilization or mating success in male Tribolium castaneum.

    PubMed

    Michalczyk, Lukasz; Martin, Oliver Y; Millard, Anna L; Emerson, Brent C; Gage, Matthew J G

    2010-11-22

    As populations decline to levels where reproduction among close genetic relatives becomes more probable, subsequent increases in homozygous recessive deleterious expression and/or loss of heterozygote advantage can lead to inbreeding depression. Here, we measure how inbreeding across replicate lines of the flour beetle Tribolium castaneum impacts on male reproductive fitness in the absence or presence of male-male competition. Effects on male evolution from mating pattern were removed by enforcing monogamous mating throughout. After inbreeding across eight generations, we found that male fertility in the absence of competition was unaffected. However, we found significant inbreeding depression of sperm competitiveness: non-inbred males won 57 per cent of fertilizations in competition, while inbred equivalents only sired 42 per cent. We also found that the P(2) 'offence' role in sperm competition was significantly more depressed under inbreeding than sperm 'defence' (P(1)). Mating behaviour did not explain these differences, and there was no difference in the viability of offspring sired by inbred or non-inbred males. Sperm length variation was significantly greater in the ejaculates of inbred males. Our results show that male ability to achieve normal fertilization success was not depressed under strong inbreeding, but that inbreeding depression in these traits occurred when conditions of sperm competition were generated.

  7. Trading or coercion? Variation in male mating strategies between two communities of East African chimpanzees

    PubMed Central

    Kaburu, Stefano S. K.; Newton-Fisher, Nicholas E.

    2015-01-01

    Across taxa, males employ a variety of mating strategies, including sexual coercion and the provision, or trading, of resources. Biological market theory (BMT) predicts that trading of commodities for mating opportunities should exist only when males cannot monopolize access to females and/or obtain mating by force, in situations where power differentials between males are low; both coercion and trading have been reported for chimpanzees (Pan troglodytes). Here, we investigate whether the choice of strategy depends on the variation in male power differentials, using data from two wild communities of East African chimpanzees (Pan troglodytes schweinfurthii): the structurally despotic Sonso community (Budongo, Uganda) and the structurally egalitarian M-group (Mahale, Tanzania). We found evidence of sexual coercion by male Sonso chimpanzees, and of trading—of grooming for mating—by M-group males; females traded sex for neither meat nor protection from male aggression. Our results suggest that the despotism–egalitarian axis influences strategy choice: male chimpanzees appear to pursue sexual coercion when power differentials are large and trading when power differentials are small and coercion consequently ineffective. Our findings demonstrate that trading and coercive strategies are not restricted to particular chimpanzee subspecies; instead, their occurrence is consistent with BMT predictions. Our study raises interesting, and as yet unanswered, questions regarding female chimpanzees’ willingness to trade sex for grooming, if doing so represents a compromise to their fundamentally promiscuous mating strategy. It highlights the importance of within-species cross-group comparisons and the need for further study of the relationship between mating strategy and dominance steepness. PMID:26279605

  8. Audience effect alters male mating preferences in zebra finches (Taeniopygia guttata).

    PubMed

    Dubois, Frédérique; Belzile, Alexandra

    2012-01-01

    The social environment of animals strongly influences the mating preferences of both the choosing and the observing individuals. Notably, there is recent evidence that polygamous males decrease their selectivity when being observed by competitors in order to direct their rivals' attention away from their true interest and, consequently, reduce sperm competition risk. Yet, other mechanisms, whose importance remains unexplored, could induce similar effects. In monogamous species with mutual choice, particularly, if males adjust their selectivity according to the risk of being rejected by their preferred mate, they should as well become less selective when potential rivals are present. Here, we investigated whether the presence of bystanders modifies male mating preferences when the risk of sperm competition is low, by carrying out mate-choice experiments with male zebra finches (Taeniopygia guttata) whose preferences for two females were measured twice: with and without an audience. We found that the presence of potential rivals had no effect on the males' choosiness. However, with an audience, they spent more time with the female that was considered as the less attractive one in the control condition. These findings support the hypothesis that monogamous males alter their mate choice decisions in the presence of a male audience to reduce the risk of remaining unpaired. Thus, our results indicate that several explanations can account for the changes in male preferences due to the presence of competitors and highlight the importance of assessing the relative role of each mechanism potentially involved, to be able to make conclusions about the effect of an audience on signal evolution.

  9. Low-oxygen atmospheric treatment improves the performance of irradiation-sterilized male cactus moths used in SIT.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As part of Sterile Insect Technique (SIT) programs, irradiation can effectively induce sterility in insects by damaging genomic DNA. However, irradiation also induces other off-target side effects that reduce the quality and performance of sterilized males. Thus, treatments that reduce off-target ef...

  10. Melanic body colour and aggressive mating behaviour are correlated traits in male mosquitofish (Gambusia holbrooki).

    PubMed Central

    Horth, Lisa

    2003-01-01

    Correlated traits are important from an evolutionary perspective as natural selection acting on one trait may indirectly affect other traits. Further, the response to selection can be constrained or hastened as a result of correlations. Because mating behaviour and body colour can dramatically affect fitness, a correlation between them can have important fitness ramifications. In this work, melanic (black) male mosquitofishes (Gambusia holbrooki) with temperature-sensitive body-colour expression are bred in captivity. Half of the sons of each melanic sire are reared at 19 degrees C (and express a black body colour) and half are reared at 31 degrees C (and express a silver body colour). The two colour morphs are placed in the same social setting and monitored for behavioural differences. Mating behaviour and colour are correlated traits. Mating behaviour differs markedly between the two phenotypes, despite high genetic relatedness. Melanic (black) phenotypes are more aggressive towards females, chasing them and attempting more matings than their silver siblings. Females avoid melanic-male mating attempts more than silver-male mating attempts. When males with temperature-sensitive colour expression are melanic and aggressive, they probably experience a very different selective regime in nature from when they are silver and less aggressive. Under some conditions (e.g. predation), melanic coloration and/or aggression is advantageous compared with silver coloration and/or less aggressive behaviour. However, under different conditions (e.g. high-frequency melanism), melanism and/or aggression appears to be disadvantageous and melanic males have reduced survival and reproduction. Selective advantages to each morph under different conditions may enable the long-term persistence of this temperature-sensitive genotype. PMID:12803892

  11. Genetic Architecture of Male Sterility and Segregation Distortion in Drosophila pseudoobscura Bogota–USA Hybrids

    PubMed Central

    Phadnis, Nitin

    2011-01-01

    Understanding the genetic basis of reproductive isolation between recently diverged species is a central problem in evolutionary genetics. Here, I present analyses of the genetic architecture underlying hybrid male sterility and segregation distortion between the Bogota and USA subspecies of Drosophila pseudoobscura. Previously, a single gene, Overdrive (Ovd), was shown to be necessary but not sufficient for both male sterility and segregation distortion in F1 hybrids between these subspecies, requiring several interacting partner loci for full manifestation of hybrid phenomena. I map these partner loci separately on the Bogota X chromosome and USA autosomes using a combination of different mapping strategies. I find that hybrid sterility involves a single hybrid incompatibility of at least seven interacting partner genes that includes three large-effect loci. Segregation distortion involves three loci on the Bogota X chromosome and one locus on the autosomes. The genetic bases of hybrid sterility and segregation distortion are at least partially—but not completely—overlapping. My results lay the foundation for fine-mapping experiments to identify the complete set of genes that interact with Overdrive. While individual genes that cause hybrid sterility or inviability have been identified in a few cases, my analysis provides a comprehensive look at the genetic architecture of all components of a hybrid incompatibility underlying F1 hybrid sterility. Such an analysis would likely be unfeasible for most species pairs due to their divergence time and emphasizes the importance of young species pairs such as the D. pseudoobscura subspecies studied here. PMID:21900263

  12. Female house mice avoid fertilization by t haplotype incompatible males in a mate choice experiment

    PubMed Central

    Manser, A; König, B; Lindholm, A K

    2015-01-01

    The t haplotype in house mice is a well-known selfish genetic element with detrimental, nonadditive fitness consequences to its carriers: recessive lethal mutations cause t/t homozygotes to perish in utero. Given the severe genetic incompatibility imposed by the t haplotype, we predict females to avoid fertilization by t haplotype incompatible males. Indeed, some of the strongest evidence for compatibility mate choice is related to the t haplotype in house mice. However, all previous evidence for compatibility mate choice in this system is based on olfactory preference. It is so far unknown how general these preferences are and whether they are relevant in an actual mating context. Here, we assess female compatibility mate choice related to t haplotypes in a setting that – for the first time – allowed females to directly interact and mate with males. This approach enabled us to analyse female behaviour during the testing period, and the resulting paternity success and fitness consequences of a given choice. We show that genetic incompatibilities arising from the t haplotype had severe indirect fitness consequences and t females avoided fertilization by t incompatible males. The results are inconclusive whether this avoidance of t fertilization by t females was caused by pre- or post-copulatory processes. PMID:25494878

  13. Segregation and Heritability of Male Sterility in Populations Derived from Progeny of Satsuma Mandarin

    PubMed Central

    Goto, Shingo; Yoshioka, Terutaka; Ohta, Satoshi; Kita, Masayuki; Hamada, Hiroko

    2016-01-01

    Male sterility derived from Satsuma mandarin (Citrus unshiu) has been used in Japanese citrus breeding programs to obtain seedless cultivars, which is a desirable trait for consumers. Male sterility has often been evaluated by anther development or pollen fertility; however, the inheritance and heritability of male sterility derived from Satsuma is poorly understood. In this study, we investigated the mode of inheritance and broad-sense heritability of male sterility derived from Satsuma. Initially, we evaluated the total number of pollen grains per anther and apparent pollen fertility, as indicated by lactophenol blue staining, in 15 citrus cultivars and selections to understand the male sterility of Satsuma. The results indicated that male sterility was primarily caused by decreased number of pollen grains per anther in progeny of Satsuma. We also evaluated these traits in three F1 populations (hyuganatsu × ‘Okitsu No. 56’, ‘Okitsu No. 46’ × ‘Okitsu No. 56’ and ‘Okitsu No. 46’ × ‘Kara’), of which the parents are derived from Satsuma. Individuals in these populations showed strong segregation for number of pollen grains per anther. The apparent fertility of pollen also showed segregation but was almost constant at 70%–90%. The estimated broad-sense heritability for the number of pollen grains per anther was as high as 0.898 in the ‘Okitsu No. 46’ × ‘Okitsu No. 56’ and ‘Okitsu No. 46’ × ‘Kara’ populations. These results indicated that the number of pollen grains per anther primarily determined male sterility among progeny of Satsuma, and this trait was inherited by the progeny. Development of DNA markers closely linked to male sterility using the F1 populations of ‘Okitsu No. 46’ × ‘Okitsu No. 56’ and ‘Okitsu No. 46’ × ‘Kara’ is expected to contribute to the breeding of novel seedless citrus cultivars. PMID:27589237

  14. Inbreeding depresses sperm competitiveness, but not fertilization or mating success in male Tribolium castaneum

    PubMed Central

    Michalczyk, Łukasz; Martin, Oliver Y.; Millard, Anna L.; Emerson, Brent C.; Gage, Matthew J. G.

    2010-01-01

    As populations decline to levels where reproduction among close genetic relatives becomes more probable, subsequent increases in homozygous recessive deleterious expression and/or loss of heterozygote advantage can lead to inbreeding depression. Here, we measure how inbreeding across replicate lines of the flour beetle Tribolium castaneum impacts on male reproductive fitness in the absence or presence of male–male competition. Effects on male evolution from mating pattern were removed by enforcing monogamous mating throughout. After inbreeding across eight generations, we found that male fertility in the absence of competition was unaffected. However, we found significant inbreeding depression of sperm competitiveness: non-inbred males won 57 per cent of fertilizations in competition, while inbred equivalents only sired 42 per cent. We also found that the P2 ‘offence’ role in sperm competition was significantly more depressed under inbreeding than sperm ‘defence’ (P1). Mating behaviour did not explain these differences, and there was no difference in the viability of offspring sired by inbred or non-inbred males. Sperm length variation was significantly greater in the ejaculates of inbred males. Our results show that male ability to achieve normal fertilization success was not depressed under strong inbreeding, but that inbreeding depression in these traits occurred when conditions of sperm competition were generated. PMID:20554548

  15. Little qualitative RNA misexpression in sterile male F1 hybrids of Drosophila pseudoobscura and D. persimilis

    PubMed Central

    Reiland, Jane; Noor, Mohamed AF

    2002-01-01

    Background Although the genetics of hybrid sterility has been the subject of evolutionary studies for over sixty years, no one has shown the reason(s) why alleles that operate normally within species fail to function in another genetic background. Several lines of evidence suggest that failures in normal gene transcription contribute to hybrid dysfunctions, but genome-wide studies of gene expression in pure-species and hybrids have not been undertaken. Here, we study genome-wide patterns of expression in Drosophila pseudoobscura, D. persimilis, and their sterile F1 hybrid males using differential display. Results Over five thousand amplifications were analyzed, and 3312 were present in amplifications from both of the pure species. Of these, 28 (0.5%) were not present in amplifications from adult F1 hybrid males. Using product-specific primers, we were able to confirm one of nine of the transcripts putatively misexpressed in hybrids. This transcript was shown to be male-specific, but without detectable homology to D. melanogaster sequence. Conclusion We tentatively conclude that hybrid sterility can evolve without widespread, qualitative misexpression of transcripts in species hybrids. We suggest that, if more misexpression exists in sterile hybrids, it is likely to be quantitative, tissue-specific, and/ or limited to earlier developmental stages. Although several caveats apply, this study was a first attempt to determine the mechanistic basis of hybrid sterility, and one potential candidate gene has been identified for further study. PMID:12223116

  16. Morphological Characterization of a New and Easily Recognizable Nuclear Male Sterile Mutant of Sorghum (Sorghum bicolor)

    PubMed Central

    Xin, Zhanguo; Huang, Jian; Smith, Ashley R.; Chen, Junping; Burke, John; Sattler, Scott E.

    2017-01-01

    Sorghum (Sorghum bicolor L. Moench) is one of the most important grain crops in the world. The nuclear male sterility (NMS) trait, which is caused by mutations on the nuclear gene, is valuable for hybrid breeding and genetic studies. Several NMS mutants have been reported previously, but none of them were well characterized. Here, we present our detailed morphological characterization of a new and easily recognizable NMS sorghum mutant male sterile 8 (ms8) isolated from an elite inbred BTx623 mutagenized by ethyl methane sulfonate (EMS). Our results show that the ms8 mutant phenotype was caused by a mutation on a single recessive nuclear gene that is different from all available NMS loci reported in sorghum. In fertile sorghum plants, yellow anthers appeared first during anthesis, while in the ms8 mutant, white hairy stigma emerged first and only small white anthers were observed, making ms8 plants easily recognizable when flowering. The ovary development and seed production after manual pollination are normal in the ms8 mutant, indicating it is female fertile and male sterile only. We found that ms8 anthers did not produce pollen grains. Further analysis revealed that ms8 anthers were defective in tapetum development, which led to the arrest of pollen formation. As a stable male sterile mutant across different environments, greenhouses, and fields in different locations, the ms8 mutant could be a useful breeding tool. Moreover, ms8 might be an important for elucidating male gametophyte development in sorghum and other plants. PMID:28052078

  17. Sterile Insect Technique and F1 Sterility in the European Grapevine Moth, Lobesia botrana

    PubMed Central

    Saour, George

    2014-01-01

    Newly emerged adults of the European grapevine moth, Lobesia botrana (Denis and Schiffermuller) (Lepidoptera: Tortricidae), were irradiated with various doses of gamma radiation and crossed to unirradiated counterparts of the opposite sex. Fecundity was decreased when unirradiated females were mated with either 300- or 350-Gy-irradiated males. Adult males that were irradiated with 400 Gy and mated with unirradiated females retained a residual fertility of 2.7%. The radiation dose at which irradiated females were found to be 100% sterile when mated with unirradiated males was 150 Gy. The inherited effects in the F1 progeny of irradiated male parents were examined at 100, 150, and 200 Gy. Fecundity and fertility of the F1 progeny of males irradiated with 150 Gy and inbred or crossed with irradiated and unirradiated moths were also recorded. A significant reduction in fertility was observed when F1 males mated with either F1 or unirradiated females. According to sterility index, F1 females who mated with F1 males had greater sterility than when F1 females were crossed to 150-Gy-irradiated males. Based upon the results of this study, 150 Gy of gamma radiation would be the optimal dose to use in a sterile insect technique and F1 sterility program against L. botrana. PMID:25373155

  18. Sterile insect technique and F₁ sterility in the European grapevine moth, Lobesia botrana.

    PubMed

    Saour, George

    2014-01-23

    Newly emerged adults of the European grapevine moth, Lobesia botrana (Denis and Schiffermuller) (Lepidoptera: Tortricidae), were irradiated with various doses of gamma radiation and crossed to unirradiated counterparts of the opposite sex. Fecundity was decreased when unirradiated females were mated with either 300-or 350-Gy-irradiated males. Adult males that were irradiated with 400 Gy and mated with unirradiated females retained a residual fertility of 2.7%. The radiation dose at which irradiated females were found to be 100% sterile when mated with unirradiated males was 150 Gy. The inherited effects in the F1 progeny of irradiated male parents were examined at 100, 150, and 200 Gy. Fecundity and fertility of the F1 progeny of males irradiated with 150 Gy and inbred or crossed with irradiated and unirradiated moths were also recorded. A significant reduction in fertility was observed when F1 males mated with either F1 or unirradiated females. According to sterility index, F1 females who mated with F1 males had greater sterility than when F1 females were crossed to 150-Gy-irradiated males. Based upon the results of this study, 150 Gy of gamma radiation would be the optimal dose to use in a sterile insect technique and F1 sterility program against L. botrana.

  19. Effects of pre-irradiation conditioning of Medfly pupae (Diptera: Tephritidae): Hypoxia and quality of sterile males

    SciTech Connect

    Nestel, D.; Nemny-Lavy, E.; Islam, S.M.; Wornoayporn, V.; Caceres, C.

    2007-03-15

    Irradiation of pupae in sterile insect technique (SIT) projects is usually undertaken in hypoxic atmospheres, which have been shown to lessen the deleterious effects of irradiation on the quality of adult sterile flies. Although this is the accepted technology in most mass-rearing and sterilization facilities, to date no information has been generated on the actual levels of oxygen (O{sub 2}) in pupae-packing containers during irradiation. The present study utilized recently-developed technology to investigate the O{sub 2} level inside bags in which pupae of Mediterranean fruit fly (medfly) Ceratitis capitata (Wiedemann) are packed prior to irradiation, the ability of pupae to create hypoxic environments in these bags, and the effect of O{sub 2} atmospheres on the quality of irradiated males. Pupae, 1 d before adult emergence, were shown to deplete the O{sub 2} level in sealed bags in approximately 1 h. The rate of O{sub 2} consumption was dependent upon pupal age and incubation temperature. Incubation temperature did not significantly affect the quality of pupae or mating capacity of resultant adult males if pupae were irradiated under maximal hypoxic conditions inside packing bags. In contrast, mating competitiveness drastically decreased when pupae were irradiated under ambient O{sub 2} conditions, with the packing bag open. There was no difference in the mating capacity of males when pupae were irradiated in sealed bags under either 10% or 2% O{sub 2} levels, or under maximal hypoxia. Normal doses of fluorescent dye, applied to pupae to mark sterile flies, did not affect the ability of pupae to create hypoxic conditions inside packing bags, nor the quality control parameters of either pupae or adults. Current practices in mass-rearing facilities are discussed in the light of these results. (author) [Spanish] La irradiacion de pupas en proyectos de mosca esteril usualmente se hace bajo condiciones de hipoxia. Esta condicion ha demostrado ser menos detrimente a

  20. Male dominance rank, mating and reproductive success in captive bonobos (Pan paniscus).

    PubMed

    Marvan, R; Stevens, J M G; Roeder, A D; Mazura, I; Bruford, M W; de Ruiter, J R

    2006-01-01

    In the recent past, application of DNA genotyping techniques has enabled researchers to more accurately test relationships between dominance rank (DR), mating success (MS) and reproductive success (RS). Paternity studies often reveal that reproductive outcome does not always correlate with male DR and/or MS and thus open room for discussion and interpretation of alternative reproductive tactics of both sexes. In this study, we analysed male DR, MS and RS in a group of bonobos at Twycross Zoo (UK). Genetic relationships were determined using 8 tetrameric microsatellite loci. Despite clear and asymmetric dominance relationships, analysed using normalised David's scores based on a dyadic index of dominance among the group's 3 mature males, we found that the most dominant male did not sire the most offspring. In fact, both infants conceived during the observation period were found to be sired by the lower-ranking males. Although the alpha male had almost exclusive mating access to one of the females during the time she was showing a maximal anogenital swelling, her infant was sired by the lowest-ranking male who mostly mated with her when outside the maximal swelling period. This result suggests that either sperm competition operates and/or ovulation is decoupled from the phase of maximal anogenital swelling which could allow greater female choice.

  1. Cryptic forcible insemination: male snakes exploit female physiology, anatomy, and behavior to obtain coercive matings.

    PubMed

    Shine, Richard; Langkilde, Tracy; Mason, Robert T

    2003-11-01

    Whether males can inseminate uncooperative females is a central determinant of mating system evolution that profoundly affects the interpretation of phenomena such as multiple mating by females, mate choice, reproductive seasonality, and courtship tactics. Forcible insemination is usually inferred from direct physical battles between the sexes and has been dismissed on intuitive grounds for many kinds of animals. For example, snakes have elongate flexible bodies (making it difficult for a male to restrain a female physically), males are typically smaller than females, and copulation requires female cloacal gaping to enable intromission. Male garter snakes (Thamnophis sirtalis) do not display any overt aggression during courtship and simply lie over the female and exhibit rhythmic pulsating caudocephalic waves of muscular contraction; previous studies have interpreted this behavior as a mechanism for eliciting female receptivity. In contrast, we show that male garter snakes forcibly inseminate females. They do so by taking advantage of specific features of snake physiology, respiratory anatomy, and antipredator behavior. The snake lung extends along most of the body, with the large posterior section (the saccular lung) lacking any respiratory exchange surface. Rhythmic caudocephalic waves by courting male garter snakes push anoxic air from the saccular lung forward and across the respiratory surfaces such that females cannot obtain oxygen. Their stress response involves cloacal gaping, which functions in other contexts to repel predators by extruding feces and musk but in this situation permits male intromission. Thus, superficially benign courtship behaviors may involve cryptic coercion even in species for which intuition dismisses any possibility of forcible insemination.

  2. Complex mitonuclear interactions and metabolic costs of mating in male seed beetles.

    PubMed

    Immonen, E; Rönn, J; Watson, C; Berger, D; Arnqvist, G

    2016-02-01

    The lack of evolutionary response to selection on mitochondrial genes through males predicts the evolution of nuclear genetic influence on male-specific mitochondrial function, for example by gene duplication and evolution of sex-specific expression of paralogs involved in metabolic pathways. Intergenomic epistasis may therefore be a prevalent feature of the genetic architecture of male-specific organismal function. Here, we assess the role of mitonuclear genetic variation for male metabolic phenotypes [metabolic rate and respiratory quotient (RQ)] associated with ejaculate renewal, in the seed beetle Callosobruchus maculatus, by assaying lines with crossed combinations of distinct mitochondrial haplotypes and nuclear lineages. We found a significant increase in metabolic rate following mating relative to virgin males. Moreover, processes associated with ejaculate renewal showed variation in metabolic rate that was affected by mitonuclear interactions. Mitochondrial haplotype influenced mating-related changes in RQ, but this pattern varied over time. Mitonuclear genotype and the energy spent during ejaculate production affected the weight of the ejaculate, but the strength of this effect varied across mitochondrial haplotypes showing that the genetic architecture of male-specific reproductive function is complex. Our findings unveil hitherto underappreciated metabolic costs of mating and ejaculate renewal, and provide the first empirical demonstration of mitonuclear epistasis on male reproductive metabolic processes.

  3. Male foraging efficiency, but not male problem-solving performance, influences female mating preferences in zebra finches

    PubMed Central

    Chantal, Véronique

    2016-01-01

    Experimental evidence suggests that females would prefer males with better cognitive abilities as mates. However, little is known about the traits reflecting enhanced cognitive skills on which females might base their mate-choice decisions. In particular, it has been suggested that male foraging performance could be used as an indicator of cognitive capacity, but convincing evidence for this hypothesis is still lacking. In the present study, we investigated whether female zebra finches (Taeniopygia guttata) modify their mating preferences after having observed the performance of males on a problem-solving task. Specifically, we measured the females’ preferences between two males once before and once after an observation period, during which their initially preferred male was incapable of solving the task contrary to their initially less-preferred male. We also conducted a control treatment to test whether the shift in female preferences was attributable to differences between the two stimulus males in their foraging efficiency. Finally, we assessed each bird’s performance in a color associative task to check whether females can discriminate among males based on their learning speed. We found that females significantly increased their preference toward the most efficient male in both treatments. Yet, there was no difference between the two treatments and we found no evidence that females assess male cognitive ability indirectly via morphological traits. Thus, our results suggest that females would not use the males’ problem-solving performance as an indicator of general cognitive ability to gain indirect fitness benefits (i.e., good genes) but rather to assess their foraging efficiency and gain direct benefits. PMID:27635358

  4. Condition-dependent mate choice and a reproductive disadvantage for MHC-divergent male tiger salamanders.

    PubMed

    Bos, David H; Williams, Rod N; Gopurenko, David; Bulut, Zafer; DeWoody, J Andrew

    2009-08-01

    Major histocompatibility complex (MHC) alleles likely have adaptive value because of overdominance, in which case MHC heterozygous individuals have increased fitness relative to homozygotes. Because of this potential benefit, the evolution of sexual reproduction between MHC-divergent individuals (i.e. negative assortative mating, NAM) may be favoured. However, the strongest evidence for MHC-based NAM comes from inbred animals, and context-dependent mating preferences have rarely been evaluated although they often occur in nature. We assessed the extent MHC-based mating preferences among wild tiger salamanders (Ambystoma tigrinum) using multiple molecular approaches. We genotyped 102 adults and 864 larvae from 36 breeding trials at both microsatellite and MHC loci. Parentage analysis revealed that reproductive success among males was positively associated with increased tail length and that with respect to the focal female, MHC-similar males sired a significantly higher number of offspring than more dissimilar males. This trend was consistent, even under context-dependent scenarios that favour traditional MHC-based NAM. These results suggest that the most MHC-divergent males may be at a reproductive disadvantage in pairwise breeding trials. Our data add to a growing body of evidence that suggests where it exists, MHC-based choice is probably dynamic and mediated by many factors that vary in the wild, notably signals from other indicator traits and by the quality and quantity of potential mates.

  5. Drosophila melanogaster females restore their attractiveness after mating by removing male anti-aphrodisiac pheromones.

    PubMed

    Laturney, Meghan; Billeter, Jean-Christophe

    2016-08-03

    Males from many species ensure paternity by preventing their mates from copulating with other males. One mate-guarding strategy involves marking females with anti-aphrodisiac pheromones (AAPs), which reduces the females' attractiveness and dissuades other males from courting. Since females benefit from polyandry, sexual conflict theory predicts that females should develop mechanisms to counteract AAPs to achieve additional copulations, but no such mechanisms have been documented. Here we show that during copulation Drosophila melanogaster males transfer two AAPs: cis-Vaccenyl Acetate (cVA) to the females' reproductive tract, and 7-Tricosene (7-T) to the females' cuticle. A few hours after copulation, females actively eject cVA from their reproductive tract, which results in increased attractiveness and re-mating. Although 7-T remains on those females, we show that it is the combination of the two chemicals that reduces attractiveness. To our knowledge, female AAP ejection provides the first example of a female mechanism that counter-acts chemical mate-guarding.

  6. Drosophila melanogaster females restore their attractiveness after mating by removing male anti-aphrodisiac pheromones

    PubMed Central

    Laturney, Meghan; Billeter, Jean-Christophe

    2016-01-01

    Males from many species ensure paternity by preventing their mates from copulating with other males. One mate-guarding strategy involves marking females with anti-aphrodisiac pheromones (AAPs), which reduces the females' attractiveness and dissuades other males from courting. Since females benefit from polyandry, sexual conflict theory predicts that females should develop mechanisms to counteract AAPs to achieve additional copulations, but no such mechanisms have been documented. Here we show that during copulation Drosophila melanogaster males transfer two AAPs: cis-Vaccenyl Acetate (cVA) to the females' reproductive tract, and 7-Tricosene (7-T) to the females' cuticle. A few hours after copulation, females actively eject cVA from their reproductive tract, which results in increased attractiveness and re-mating. Although 7-T remains on those females, we show that it is the combination of the two chemicals that reduces attractiveness. To our knowledge, female AAP ejection provides the first example of a female mechanism that counter-acts chemical mate-guarding. PMID:27484362

  7. Low incidence of miscarriage induced by the scent of male littermates of original mates: male kinship reduces the bruce effect in female mice, Mus musculus.

    PubMed

    Wang, Yuting; Liu, Dingzhen

    2013-01-01

    The scent of a novel male can elicit pregnancy block in recently mated female mice (Mus musculus), a phenomenon known as the Bruce effect. Despite abundant literature on the Bruce effect in rodents, it remains unclear whether males related to a female's original mate can induce the Bruce effect in out-bred, communally living mice. We investigated this question using Kunming (KM) male mice of varying genetic relatedness. Recently mated females were subjected to three treatments: exposure to the urine of the mate, urine of the mate's male littermate, and urine of a male unrelated to the mate. It was found that the urine of male littermates of the females' mates did not elicit more pregnancy block than that of the females' mates. However, the urine of novel males caused a higher rate of female miscarriage than that of the females' mates. By using a habituation-dishabituation paradigm, we found that unmated females could discriminate the urine scents of two male littermates from those of a novel male unrelated to the littermates. To understand how females use urinary cues to discriminate between males with different genetic relationships, we used gas chromatography coupled with mass spectrometry (GC-MS) to examine the volatile composition of urine from males with varying relatedness. It was found that KM male littermates shared similar volatile compositions in their urine. Our results suggest that male kinship reduces the Bruce effect in female KM mice, and provide additional evidence for mate choice being partly mediated by the Bruce effect in KM mice.

  8. Absorption and distribution of estradiol from male seminal emissions during mating

    PubMed Central

    Pollock, Tyler

    2016-01-01

    Estradiol-17β (E2) plays critical roles in female maturation, sexual receptivity, ovulation and fertility. In many mammals, contact with males can similarly affect these female parameters, whereas male excretions contain significant quantities of E2. We administered radiolabeled estradiol ([3H]E2) to male mice in doses representing a small fraction of their endogenous E2. These males were paired with sexually receptive females, and radioactivity was traced into the females’ systems. In Experiment 1, males were given [3H]E2 at 24 and 1 h before mating. Male-to-female [3H]E2 transfer intensified with increasing numbers of intromissions and spiked in the uterus after insemination. In Experiment 2, sexually experienced young males received [3H]E2 at 72 and 24 h before mating, and all mated to ejaculation. The copulatory plug deposited in the female reproductive tract contained substantial levels of radioactivity. The uteri, other tissues and blood serum of females displayed radioactivity indicative of E2 transfer. In Experiment 3, radioactivity was observed 3 and 18 h after insemination in the females’ uteri and other tissues, including parts of the brain. In Experiment 4, we observed substantial levels of radioactivity in semen as well as the copulatory plugs retrieved from the females after mating. Transferred E2 could directly affect abundant estrogen receptors in the female reproductive tract without potential metabolism by the liver. Sexually transferred E2 may facilitate uterine preparation for blastocyst implantation. These data converge with several lines of evidence indicating that male-sourced E2 can transfer to proximate females in bioactive form, contributing to various mammalian pheromonal effects. PMID:27758953

  9. Descending protocerebral neurons related to the mating dance of the male silkworm moth.

    PubMed

    Kanzaki, R; Shibuya, T

    1986-07-09

    Descending protocerebral neurons in the male silkworm moth brain responding to the sexual pheromone (Bombykol) were identified. The neurons responded well with a tonic type of response and the high-frequency spikes evoked continued even after the end of the stimulus. Characteristics of the dose-response curves of the neurons to the pheromone remarkably resembled those of the wing vibration which is one of the mating behavioral components of the male moths.

  10. The role of testosterone in male downy woodpeckers in winter home range use, mate interactions and female foraging behaviour.

    PubMed

    Kellam, James S; Lucas, Jeffrey R; Wingfield, John C

    2006-03-01

    Studies of the role of testosterone (T) in birds have typically focused on sexual or aggressive behaviours of males during the breeding period, but males of nonmigratory species may invest in mate and territory long before breeding, and the influence of T in facilitating nonbreeding-season behaviours is poorly understood. We gave free-living male downy woodpeckers, Picoides pubescens, T-implants during the winter to determine whether elevated levels of T increased a male's ability to exclusively occupy territory-based resources, and whether elevated T strengthened a male's investment in an existing pair bond relationship. We also explored how a female's foraging efficiency might be affected by her mate's behaviour if he had elevated T. We found little difference between control and T-implanted males with regard to home range exclusivity. Surprisingly, male-male display rates were significantly lower in T-implanted males than in controls. Regarding male-female interactions, T-implanted males that experienced high incursion rates from other males maintained more frequent spatial association with their mate, suggesting that T facilitates male behaviours that could restrict the mate's access to other male birds. Female mates of T-males showed reduced foraging rates, but because male-female aggression was similar between treatment groups, the cause for this reduction is unknown. The results indicate that exogenous T during winter affects a variety of behaviours in male woodpeckers, and proximate influences on pair bond maintenance in winter may be a fruitful avenue for future research.

  11. Identification of fertiity restores for S male-sterile maize: beyond PPRs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nuclear genes are essential for expression of the mitochondrial genome and for the function of mitochondrial protein complexes. Interaction of the plant mitochondrial and nuclear genetic systems is exemplified by mitochondrial-encoded cytoplasmic male sterility (CMS) under the control of nuclear fe...

  12. Cytoplasmic effects on DNA methylation between male sterile line and its maintainer in rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hybrid rice is advantageous over the traditional one on food production, which is important to support the increasing world’s population, especially in the developing countries. Three-line system that has played a major role since the 1970s in rice includes male sterile (A line), its maintainer (B l...

  13. Molecular mapping of three nuclear male sterility mutant genes in cultivated sunflower (Helianthus annuus L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The nuclear male sterility (NMS) trait is a useful tool for sunflower (Helianthus annuus L.) breeding and genetic programs. Previously, we induced NMS mutants in cultivated line HA 89. The mutants possessed single recessive genes, ms6, ms7, and ms8, respectively, in NMS HA 89-872, NMS HA 89-552, and...

  14. Morphological characterization of a new and easily recognizable nuclear male sterile mutant of sorghum (Sorghum bicolor).

    Technology Transfer Automated Retrieval System (TEKTRAN)

    All commercial sorghum (Sorghum bicolor L. Moench) hybrids are produced using A1 cytoplasmic male sterility (CMS) lines. However, this homogenous cytoplasm could predispose sorghum to devastating diseases. Furthermore, it is expensive to develop and maintain the CMS-based breeding system, because it...

  15. Involvement of a universal amino acid synthesis impediment in cytoplasmic male sterility in pepper

    PubMed Central

    Fang, Xianping; Fu, Hong-Fei; Gong, Zhen-Hui; Chai, Wei-Guo

    2016-01-01

    To explore the mechanisms of pepper (Capsicum annuum L.) cytoplasmic male sterility (CMS), we studied the different maturation processes of sterile and fertile pepper anthers. A paraffin section analysis of the sterile anthers indicated an abnormality of the tapetal layer and an over-vacuolization of the cells. The quantitative proteomics results showed that the expression of histidinol dehydrogenase (HDH), dihydroxy-acid dehydratase (DAD), aspartate aminotransferase (ATAAT), cysteine synthase (CS), delta-1-pyrroline-5-carboxylate synthase (P5CS), and glutamate synthetase (GS) in the amino acid synthesis pathway decreased by more than 1.5-fold. Furthermore, the mRNA and protein expression levels of DAD, ATAAT, CS and P5CS showed a 2- to 16-fold increase in the maintainer line anthers. We also found that most of the amino acid content levels decreased to varying degrees during the anther tapetum period of the sterile line, whereas these levels increased in the maintainer line. The results of our study indicate that during pepper anther development, changes in amino acid synthesis are significant and accompany abnormal tapetum maturity, which is most likely an important cause of male sterility in pepper. PMID:26987793

  16. Sexual Signalling in Propithecus verreauxi: Male “Chest Badge” and Female Mate Choice

    PubMed Central

    Dall'Olio, Stefania; Norscia, Ivan; Antonacci, Daniela; Palagi, Elisabetta

    2012-01-01

    Communication, an essential prerequisite for sociality, involves the transmission of signals. A signal can be defined as any action or trait produced by one animal, the sender, that produces a change in the behaviour of another animal, the receiver. Secondary sexual signals are often used for mate choice because they may inform on a potential partner's quality. Verreaux's sifaka (Propithecus verreauxi) is characterized by the presence of two different morphs of males (bimorphism), which can show either a stained or clean chest. The chest becomes stained by secretions of the sternal gland during throat marking (rubbing throat and chest on a vertical substrate while smearing the scent deposition). The role of the chest staining in guiding female mate choice was previously hypothesized but never demonstrated probably due to the difficulty of observing sifaka copulations in the wild. Here we report that stained-chested males had a higher throat marking activity than clean-chested males during the mating season, but not during the birth season. We found that females copulated more frequently with stained-chested males than the clean-chested males. Finally, in agreement with the biological market theory, we found that clean-chested males, with a lower scent-releasing potential, offered more grooming to females. This “grooming for sex” tactic was not completely unsuccessful; in fact, half of the clean-chested males copulated with females, even though at low frequency. In conclusion, the chest stain, possibly correlated with different cues targeted by females, could be one of the parameters which help females in selecting mates. PMID:22615982

  17. Subadult experience influences adult mate choice in an arthropod: exposed female wolf spiders prefer males of a familiar phenotype.

    PubMed

    Hebets, Eileen A

    2003-11-11

    Current sexual selection theory proposes several potential mechanisms driving the evolution of female mating preferences, few of which involve social interactions. Although vertebrate examples of socially influenced mating preferences do exist, the invertebrate examples are virtually nonexistent. Here I demonstrate that the mating preferences of female wolf spiders can be acquired through exposure as subadults to unrelated, sexually active adult males. I first conducted exposure trials during which subadult females of the wolf spider Schizocosa uetzi were allowed to interact with mature males of an experimentally manipulated phenotype (either black or brown forelegs). After maturation, these previously exposed females were paired with a male of either a familiar or unfamiliar manipulated phenotype for mate-choice trials. Subadult females that were exposed to directed courtship by mature males of a particular morphological phenotype were subsequently more likely to mate with a male of a familiar phenotype as adults. Furthermore, females that were exposed as subadults were more likely, as adults, to cannibalize a courting male with an unfamiliar phenotype. Unexposed females did not distinguish between phenotypes in either mate choice or cannibalism frequency. These results suggest a previously uncharacterized mechanism influencing the origin of female mating preferences and ultimately the evolution of male traits: subadult experience. This study also stresses the potential importance of learning and memory on adult mate choice in an arthropod.

  18. A novel male sterility-fertility restoration system in plants for hybrid seed production.

    PubMed

    Singh, Surendra Pratap; Singh, Sudhir P; Pandey, Tripti; Singh, Ram Rakshpal; Sawant, Samir V

    2015-06-15

    Hybrid seeds are used for stimulated crop production, as they harness heterosis. The achievement of complete male-sterility in the female-parent and the restored-fertility in F1-hybrids are the major bottlenecks in the commercial hybrid seed production. Here, we report a male sterility-fertility restoration system by engineering the in most nutritive anther wall layer tapetum of female and male parents. In the female parent, high-level, and stringent expression of Arabidopsis autophagy-related gene BECLIN1 was achieved in the tapetum, which altered the tapetal degeneration program, leading to male sterility. This works on our previously demonstrated expression cassette based on functional complementation of TATA-box mutant (TGTA) promoter and TATA-binding protein mutant3 (TBPm3), with modification by conjugating Long Hypocotyle in Far-Red1 fragment (HFR1(NT131)) with TBPm3 (HFR1(NT131)-TBPm3) to exercise regulatory control over it. In the male parent, tapetum-specific Constitutive photo-morphogenesis1 (COP1) was expressed. The F1 obtained by crossing these engineered parents showed decreased BECLIN1 expression, which was further completely abolished when COP1-mutant (COP1(L105A)) was used as a male parent, leading to normal tapetal development and restored fertility. The system works on COP1-HFR1 interaction and COP1-mediated degradation of TBPm3 pool (HFR1(NT131)-TBPm3). The system can be deployed for hybrid seed production in agricultural crops.

  19. Sexual cooperation and conflict in butterflies: a male-transferred anti-aphrodisiac reduces harassment of recently mated females.

    PubMed

    Andersson, J; Borg-Karlson, A K; Wiklund, C

    2000-07-07

    Sexual selection theory predicts that the different selection pressures on males and females result in sexual conflict. However, in some instances males and females share a common interest which could lead to sexual cooperation. In the pierid butterfly Pieris napi the male and the recently mated female share a common interest in reducing female harassment by other males soon after mating. Here we show that P. napi males transfer an anti-aphrodisiac to the female at mating, methyl-salicylate (MeS), which is a volatile substance which mated females emit when courted and which makes males quickly abandon them. A 13C-labelling experiment demonstrated that only males synthesize MeS. The effect of this antiaphrodisiac is so strong that most males will refrain from mating with virgin females to whom MeS has been artificially applied. In P. napi, males also transfer nutrients to females at mating. This increases female fecundity and longevity and so females benefit from remating. Hence, sexual cooperation gradually turns to conflict. Future research is required to reveal which sex controls the gradual decrease in the MeS titre which is necessary for allowing mated females to regain attractiveness and remate.

  20. Cuticular Hydrocarbon Content that Affects Male Mate Preference of Drosophila melanogaster from West Africa

    PubMed Central

    Takahashi, Aya; Fujiwara-Tsujii, Nao; Yamaoka, Ryohei; Itoh, Masanobu; Ozaki, Mamiko; Takano-Shimizu, Toshiyuki

    2012-01-01

    Intraspecific variation in mating signals and preferences can be a potential source of incipient speciation. Variable crossability between Drosophila melanogaster and D. simulans among different strains suggested the abundance of such variations. A particular focus on one combination of D. melanogaster strains, TW1(G23) and Mel6(G59), that showed different crossabilities to D. simulans, revealed that the mating between females from the former and males from the latter occurs at low frequency. The cuticular hydrocarbon transfer experiment indicated that cuticular hydrocarbons of TW1 females have an inhibitory effect on courtship by Mel6 males. A candidate component, a C25 diene, was inferred from the gas chromatography analyses. The intensity of male refusal of TW1 females was variable among different strains of D. melanogaster, which suggested the presence of variation in sensitivity to different chemicals on the cuticle. Such variation could be a potential factor for the establishment of premating isolation under some conditions. PMID:22536539

  1. UV-Deprived Coloration Reduces Success in Mate Acquisition in Male Sand Lizards (Lacerta agilis)

    PubMed Central

    Olsson, Mats; Andersson, Staffan; Wapstra, Erik

    2011-01-01

    Background Recent work on animal signals has revealed a wide occurrence of UV signals in tetrapods, in particular birds, but also in lizards (and perhaps other Squamate reptiles). Our previous work on the Swedish sand lizard (Lacerta agilis) has verified, both in correlative selection analyses in the wild and with laboratory and field experiments, the importance of the green ‘badge’ on the body sides of adult males for securing mating opportunities, probably mostly through deterring rival males rather than attracting females. The role of UV in communication has, however, never been examined. Methodology/Principal Findings Here we show that when measured immediately after spring skin shedding, there is also signaling in the UV. By UV-depriving the signal (reflectance) with sun block chemicals fixated with permeable, harmless spray dressing, we show that males in the control group (spray dressing only) had significantly higher success in mate acquisition than UV-deprived males. Conclusions/Significance These results suggest that at least two colour traits in sand lizards, badge area and UV, contribute to rival deterrence and/or female choice on UV characters, which elevates success in mate acquisition in UV intact male sand lizards. PMID:21602928

  2. Genetic Architecture of Hybrid Male Sterility in Drosophila: Analysis of Intraspecies Variation for Interspecies Isolation

    PubMed Central

    Reed, Laura K.; LaFlamme, Brooke A.; Markow, Therese A.

    2008-01-01

    Background The genetic basis of postzygotic isolation is a central puzzle in evolutionary biology. Evolutionary forces causing hybrid sterility or inviability act on the responsible genes while they still are polymorphic, thus we have to study these traits as they arise, before isolation is complete. Methodology/Principal Findings Isofemale strains of D. mojavensis vary significantly in their production of sterile F1 sons when females are crossed to D. arizonae males. We took advantage of the intraspecific polymorphism, in a novel design, to perform quantitative trait locus (QTL) mapping analyses directly on F1 hybrid male sterility itself. We found that the genetic architecture of the polymorphism for hybrid male sterility (HMS) in the F1 is complex, involving multiple QTL, epistasis, and cytoplasmic effects. Conclusions/Significance The role of extensive intraspecific polymorphism, multiple QTL, and epistatic interactions in HMS in this young species pair shows that HMS is arising as a complex trait in this system. Directional selection alone would be unlikely to maintain polymorphism at multiple loci, thus we hypothesize that directional selection is unlikely to be the only evolutionary force influencing postzygotic isolation. PMID:18728782

  3. Single-layer tungsten oxide as intelligent photo-responsive nanoagents for permanent male sterilization.

    PubMed

    Liu, Zhen; Liu, Xianjun; Ran, Xiang; Ju, Enguo; Ren, Jinsong; Qu, Xiaogang

    2015-11-01

    Permanent male sterilization has been recognized as useful tools for the development of neuter experimental animals and fattening livestock, as well as efficient control of pet overpopulation. Traditional routes such as surgical ways, chemical injections, and anti-fertility vaccines have addressed these crucial problems with idea outcomes. However, these routes usually bring out serious pain and infection towards animals, as well as induce long-term adverse reaction and immune suppression. Thus, a convenient, but non-surgical strategy for male sterilization under a mild manner is highly desirable. Here, for the first time, we demonstrate a novel platform for male sterilization by using single-layer WO2.72 nanosheets as smart photo-responsive sterilants. Upon a 980 nm irradiation, these nanoagents can possess intrinsic NIR-induced hyperthermia and sensitize the formation of singlet oxygen due to the cooperation of photothermal and photodynamic effects. Mechanism of cellular injury can be attributed to the denaturation of protein and apoptosis-related death. Moreover, long-term toxicity and possible metabolism route after testicular injection are discussed, indicating the neglectable systemic toxicity and high bio-compatibility of our nanoagents. Overall, our strategy can extremely overcome the shortcomings in various routine routes and suggest the new biological application of nanomaterials.

  4. Genetic Variation and Covariation in Male Attractiveness and Female Mating Preferences in Drosophila melanogaster

    PubMed Central

    Ratterman, Nicholas L.; Rosenthal, Gil G.; Carney, Ginger E.; Jones, Adam G.

    2013-01-01

    How mating preferences evolve remains one of the major unsolved mysteries in evolutionary biology. One major impediment to the study of ornament-preference coevolution is that many aspects of the theoretical literature remain loosely connected to empirical data. Theoretical models typically streamline mating preferences by describing preference functions with a single parameter, a modeling convenience that may veil important aspects of preference evolution. Here, we use a high-throughput behavioral assay in Drosophila melanogaster to quantify attractiveness and multiple components of preferences in both males and females. Females varied genetically with respect to how they ranked males in terms of attractiveness as well as the extent to which they discriminated among different males. Conversely, males showed consistent preferences for females, suggesting that D. melanogaster males tend to rank different female phenotypes in the same order in terms of attractiveness. Moreover, we reveal a heretofore undocumented positive genetic correlation between male attractiveness and female choosiness, which is a measure of the variability in a female’s response to different male phenotypes. This genetic correlation sets the stage for female choosiness to evolve via a correlated response to selection on male traits and potentially adds a new dimension to the Fisherian sexual selection process. PMID:24212081

  5. Poeciliid male mate preference is influenced by female size but not by fecundity

    PubMed Central

    Schlupp, Ingo

    2013-01-01

    While female mate preference is very well studied, male preference has only recently begun to receive significant attention. Its existence is found in numerous taxa, but empirical research has mostly been limited to a descriptive level and does not fully address the factors influencing its evolution. We attempted to address this issue using preference functions by comparing the strength of male preference for females of different sizes in nine populations of four poeciliid species. Due to environmental constraints (water toxicity and surface versus cave habitat), females from these populations vary in the degree to which their size is correlated to their fecundity. Hence, they vary in how their size signals their quality as mates. Since female size is strongly correlated with fecundity in this subfamily, males were sequentially presented with conspecific females of three different size categories and the strength of their preference for each was measured. Males preferred larger females in all populations, as predicted. However, the degree to which males preferred each size category, as measured by association time, was not correlated with its fecundity. In addition, cave males discriminated against smaller females more than surface males. Assuming that male preference is correlated with female fitness, these results suggest that factors other than fecundity have a strong influence on female fitness in these species. PMID:24010018

  6. Alternative male mating tactics of the substrate brooding cichlid Telmatochromis temporalis in Lake Tanganyika.

    PubMed

    Katoh, Rei; Munehara, Hiroyuki; Kohda, Masanori

    2005-05-01

    Telmatochromis temporalis is a bi-parental substrate brooding cichlid endemic to Lake Tanganyika. Paired males were always larger than their mates and had territories around nests against conspecific males. However, males smaller than the paired females were found in 18% of the nests. Here we report a reproductive tactic of these small males. The small males had as heavy gonads as paired males, and the gonad somatic index (GSI) of the small males was much higher than that of the latter. The examinations of the paternity and maternity using microsatellite-DNA as a genetic marker revealed that the small males were not genetically related to the pair members, and sired some young in 3 of 5 nests. These small males did not guard the broods, suggesting that they are likely to perform reproductive parasitism as sneakers. Paired males could not enter their spawning nests due to their large size, which made it difficult to chase out sneakers once they entered the nest. Some males as small as the sneakers were found outside the territories of paired males, and their gonads were quite small. Circumstantial evidence suggests that small males have two alternative investment patterns: investing in gonad to be sneakers, and investing in growth to probably be territorial males.

  7. Hybridization using cytoplasmic male sterility, cytoplasmic herbicide tolerance, and herbicide tolerance from nuclear genes

    SciTech Connect

    Beversdorf, W.D.; Erickson, L.R.; Grant, I.

    1987-04-14

    An improved process is described for producing a substantially homogeneous population of plants of a predetermined hybrid variety of crop which is capable of undergoing self-pollination and cross-pollination. The process comprises: growing in a first planting area a substantially random population of cytoplasmic male sterile plants which exhibit cytoplasmic herbicide tolerance to at least one Type A herbicide and exhibit tolerance to at least one Type B herbicide which is attributable solely to homozygous dominant nuclear genes and male fertile plants which are homozygous recessive maintainer plants for the cytoplasmic male sterile plants and which lack the cytoplasmic herbicide tolerance to at least one Type A herbicide and exhibit tolerance to at least one Type B herbicide attributable solely to the homozygous dominant nuclear genes.

  8. Antisense inhibition of mitochondrial pyruvate dehydrogenase E1alpha subunit in anther tapetum causes male sterility.

    PubMed

    Yui, Rika; Iketani, Satoru; Mikami, Tetsuo; Kubo, Tomohiko

    2003-04-01

    We hypothesized that cytoplasmic male sterility (CMS) in sugar beet may be the consequence of mitochondrial dysfunctions affecting normal anther development. To test the hypothesis, we attempted to mimic the sugar beet CMS phenotype by inhibiting the expression of mitochondrial pyruvate dehydrogenase (PDH), which is essential for the operation of the tricarboxylic acid (TCA) cycle. Screening with a cDNA library of sugar beet flower buds allowed the identification of two PDH E1alpha subunit genes (bvPDH_E1alpha-1 and bvPDH_E1alpha-2). bvPDH_E1alpha-1 was found to be highly expressed in tap roots, whereas bvPDH_E1alpha-2 was expressed most abundantly in flower buds. Green fluorescent protein (GFP) fusion of bvPDH_E1alpha revealed mitochondrial targeting properties. A 300-bp bvPDH_E1alpha-1 cDNA sequence (from +620 to +926) was connected to a tapetum-specific promoter in the antisense orientation and then introduced into tobacco. Antisense expression of bvPDH_E1alpha-1 resulted in conspicuously decreased endogenous bvPDH_E1alpha-1 transcripts and male sterility. The tapetum in the male-sterile anthers showed swelling or abnormal vacuolation. It is also worth noting that in the sterile anthers, cell organelles, such as elaioplasts, tapetosomes and orbicules were poorly formed and microspores exhibited aberrant exine development. These features are shared by sugar beet CMS. The results thus clearly indicate that inhibition of PDH activity in anther tapetum is sufficient to cause male sterility, a phenocopy of the sugar beet CMS.

  9. A barley PHD finger transcription factor that confers male sterility by affecting tapetal development.

    PubMed

    Fernández Gómez, José; Wilson, Zoe A

    2014-08-01

    Controlling pollen development is of major commercial importance in generating hybrid crops and selective breeding, but characterized genes for male sterility in crops are rare, with no current examples in barley. However, translation of knowledge from model species is now providing opportunities to understand and manipulate such processes in economically important crops. We have used information from regulatory networks in Arabidopsis to identify and functionally characterize a barley PHD transcription factor MALE STERTILITY1 (MS1), which expresses in the anther tapetum and plays a critical role during pollen development. Comparative analysis of Arabidopsis, rice and Brachypodium genomes was used to identify conserved regions in MS1 for primer design to amplify the barley MS1 gene; RACE-PCR was subsequently used to generate the full-length sequence. This gene shows anther-specific tapetal expression, between late tetrad stage and early microspore release. HvMS1 silencing and overexpression in barley resulted in male sterility. Additionally, HvMS1 cDNA, controlled by the native Arabidopsis MS1 promoter, successfully complemented the homozygous ms1 Arabidopsis mutant. These results confirm the conservation of MS1 function in higher plants and in particular in temperate cereals. This has provided the first example of a characterized male sterility gene in barley, which presents a valuable tool for the future control of male fertility in barley for hybrid development.

  10. Male mating strategy and the introgression of a growth hormone transgene

    PubMed Central

    Valosaari, Kata-Riina; Aikio, Sami; Kaitala, Veijo

    2008-01-01

    Escaped transgenic organisms (GMO's) may threaten the populations of their wild relatives if able to hybridize with each other. The introgression of a growth enhancement transgene into a wild Atlantic salmon population may be affected by the transgene's effects not only on fitness parameters, but also on mating behaviour. Large anadromous GMO males are most preferred in mating, but a transgene can also give the large sneakers a reproductive advantage over the smaller wild individuals. With a simulation model, we studied whether the increase in the proportion and mating success of sneakers in transgenic and hybrid genotypes could facilitate the introgression of a transgene into wild population after the release of GMOs. The model combines population dynamics and Mendelian inheritance of a transgenic trait. We found that the introgression of the transgene is strongly affected by the greater mating preference of large GMO males. Furthermore, the difference in reproductive success between the anadromous versus sneaker strategy defines how much GMO's have to be preferred to be able to invade. These results emphasize the importance of detailed knowledge of reproductive systems and the effect of a transgene on the phenotype and behaviour of GMOs when assessing the consequences of their release or escape to the wild. PMID:25567801

  11. Male mating strategy and the introgression of a growth hormone transgene.

    PubMed

    Valosaari, Kata-Riina; Aikio, Sami; Kaitala, Veijo

    2008-11-01

    Escaped transgenic organisms (GMO's) may threaten the populations of their wild relatives if able to hybridize with each other. The introgression of a growth enhancement transgene into a wild Atlantic salmon population may be affected by the transgene's effects not only on fitness parameters, but also on mating behaviour. Large anadromous GMO males are most preferred in mating, but a transgene can also give the large sneakers a reproductive advantage over the smaller wild individuals. With a simulation model, we studied whether the increase in the proportion and mating success of sneakers in transgenic and hybrid genotypes could facilitate the introgression of a transgene into wild population after the release of GMOs. The model combines population dynamics and Mendelian inheritance of a transgenic trait. We found that the introgression of the transgene is strongly affected by the greater mating preference of large GMO males. Furthermore, the difference in reproductive success between the anadromous versus sneaker strategy defines how much GMO's have to be preferred to be able to invade. These results emphasize the importance of detailed knowledge of reproductive systems and the effect of a transgene on the phenotype and behaviour of GMOs when assessing the consequences of their release or escape to the wild.

  12. Female brain size affects the assessment of male attractiveness during mate choice

    PubMed Central

    Corral-López, Alberto; Bloch, Natasha I.; Kotrschal, Alexander; van der Bijl, Wouter; Buechel, Severine D.; Mank, Judith E.; Kolm, Niclas

    2017-01-01

    Mate choice decisions are central in sexual selection theory aimed to understand how sexual traits evolve and their role in evolutionary diversification. We test the hypothesis that brain size and cognitive ability are important for accurate assessment of partner quality and that variation in brain size and cognitive ability underlies variation in mate choice. We compared sexual preference in guppy female lines selected for divergence in relative brain size, which we have previously shown to have substantial differences in cognitive ability. In a dichotomous choice test, large-brained and wild-type females showed strong preference for males with color traits that predict attractiveness in this species. In contrast, small-brained females showed no preference for males with these traits. In-depth analysis of optomotor response to color cues and gene expression of key opsins in the eye revealed that the observed differences were not due to differences in visual perception of color, indicating that differences in the ability to process indicators of attractiveness are responsible. We thus provide the first experimental support that individual variation in brain size affects mate choice decisions and conclude that differences in cognitive ability may be an important underlying mechanism behind variation in female mate choice. PMID:28345039

  13. Post-Mating Interactions and Their Effects on Fitness of Female and Male Echinothrips americanus (Thysanoptera: Thripidae), a New Insect Pest in China

    PubMed Central

    Li, Xiao-Wei; Jiang, Hong-Xue; Zhang, Xiao-Chen; Shelton, Anthony M.; Feng, Ji-Nian

    2014-01-01

    Post-mating, sexual interactions of opposite sexes differ considerably in different organisms. Post-mating interactions such as re-mating behavior and male harassment can affect the fitness of both sexes. Echinothrips americanus is a new insect pest in Mainland China, and little is known about its post-mating interactions. In this study, we observed re-mating frequency and male harassment frequency and their effects on fitness parameters and offspring sex ratios of E. americanus females. Furthermore, we tested the impact of mating and post-mating interactions on fitness parameters of males. Our results revealed that the re-mating frequency in female adults was extremely low during a 30-day period. However, post-mating interactions between females and males, consisting mainly of male harassment and female resistance, did occur and significantly reduced female longevity and fecundity. Interestingly, increased access to males did not affect the ratio of female offspring. For males, mating dramatically reduced their longevity. However, post-mating interactions with females had no effects on the longevity of mated males. These results enrich our basic knowledge about female and male mating and post-mating behaviors in this species and provide important information about factors that may influence population regulation of this important pest species. PMID:24489956

  14. Male Megacyllene robiniae (Coleoptera: Cerambycidae) use multiple tactics when aggressively competing for mates.

    PubMed

    Ray, Ann M; Ginzel, Matthew D; Hanks, Lawrence M

    2009-04-01

    Adult male Megacyllene robiniae (Förster) (Coleoptera: Cerambycidae) that are paired with a female often are challenged by conspecific males that attempt to displace them. In staged laboratory bouts, challenging males used seven distinct tactics to displace defending males, including wedging their head between the defender and the female (termed wedging), straddling the mated pair and pulling the defender off (prying), pulling it with the mandibles, batting it with the antennae, or pushing, biting, or kicking the defender. Individual challengers attempted as many as six different tactics in a single bout, repeating certain tactics multiple times. They often attempted tactics that were not very effective. For example, prying was one of the most common attempted tactics but was rarely effective. However, few challengers attempted to push defenders off the female, even though that tactic often was effective. Challengers apparently were influenced by context in their choice of particular tactics. For example, males that approached the mated pair from the side were likely to use wedging, whereas those approaching head on were more likely to bat with the antennae. Choice of tactic apparently was not influenced by absolute size of challengers, nor was it strongly influenced by relative size of defenders. However, the effectiveness of tactics varied significantly with relative body size: larger challengers were most successful when prying or pushing, while smaller challengers were most successful when biting and kicking. By using different tactics, relatively small males were as adept as larger males at displacing rivals.

  15. Whole Mitochondrial Genome Sequencing and Re-Examination of a Cytoplasmic Male Sterility-Associated Gene in Boro-Taichung-Type Cytoplasmic Male Sterile Rice

    PubMed Central

    Kazama, Tomohiko; Toriyama, Kinya

    2016-01-01

    Nuclear genome substitutions between subspecies can lead to cytoplasmic male sterility (CMS) through incompatibility between nuclear and mitochondrial genomes. Boro-Taichung (BT)-type CMS rice was obtained by substituting the nuclear genome of Oryza sativa subsp. indica cultivar Chinsurah Boro II with that of Oryza sativa subsp. japonica cultivar Taichung 65. In BT-type CMS rice, the mitochondrial gene orf79 is associated with male sterility. A complete sequence of the Boro-type mitochondrial genome responsible for BT-type CMS has not been determined to date. Here, we used pyrosequencing to construct the Boro-type mitochondrial genome. The contiguous sequences were assembled into five circular DNA molecules, four of which could be connected into a single circle. The two resulting subgenomic circles were unable to form a reliable master circle, as recombination between them was scarcely detected. We also found an unequal abundance of DNA molecules for the two loci of atp6. These results indicate the presence of multi-partite DNA molecules in the Boro-type mitochondrial genome. Expression patterns were investigated for Boro-type mitochondria-specific orfs, which were not found in the mitochondria from the standard japonica cultivar Nipponbare. Restorer of fertility 1 (RF1)-dependent RNA processing has been observed in orf79-containing RNA but was not detected in other Boro-type mitochondria-specific orfs, supporting the conclusion that orf79 is a unique CMS-associated gene in Boro-type mitochondria. PMID:27414645

  16. Creating Completely Both Male and Female Sterile Plants by Specifically Ablating Microspore and Megaspore Mother Cells

    PubMed Central

    Huang, Jian; Smith, Ashley R.; Zhang, Tianyu; Zhao, Dazhong

    2016-01-01

    Although genetically modified (GM) plants have improved commercially important traits, such as biomass and biofuel production, digestibility, bioremediation, ornamental value, and tolerance to biotic and abiotic stresses, there remain economic, political, or social concerns over potential ecological effects of transgene flow from GM plants. The current solution for preventing transgene flow from GM plants is genetically engineering sterility; however, approaches to generating both male and female sterility are limited. In addition, existing strategies for creating sterility lead to loss or modifications of entire flowers or floral organs. Here, we demonstrate that instead of the 1.5-kb promoter, the entire SOLO DANCERS (SDS) gene is required for its meiocyte-specific expression. We then developed an efficient method to specifically ablate microspore and megaspore mother cells using the SDS and BARNASE fusion gene, which resulted in complete sterility in both male and female reproductive organs in Arabidopsis (Arabidopsis thaliana) and tobacco (Nicotiana tabacum), but did not affect plant growth or development, including the formation of all flower organs. Therefore, our research provides a general and effective tool to prevent transgene flow in GM plants. PMID:26870055

  17. A male sterility-associated mitochondrial protein in wild beets causes pollen disruption in transgenic plants.

    PubMed

    Yamamoto, Masayuki P; Shinada, Hiroshi; Onodera, Yasuyuki; Komaki, Chihiro; Mikami, Tetsuo; Kubo, Tomohiko

    2008-06-01

    In higher plants, male reproductive (pollen) development is known to be disrupted in a class of mitochondrial mutants termed cytoplasmic male sterility (CMS) mutants. Despite the increase in knowledge regarding CMS-encoding genes and their expression, definitive evidence that CMS-associated proteins actually cause pollen disruption is not yet available in most cases. Here we compare the translation products of mitochondria between the normal fertile cytoplasm and the male-sterile I-12CMS(3) cytoplasm derived from wild beets. The results show a unique 12 kDa polypeptide that is present in the I-12CMS(3) mitochondria but is not detectable among the translation products of normal mitochondria. We also found that a mitochondrial open reading frame (named orf129) was uniquely transcribed in I-12CMS(3) and is large enough to encode the novel 12 kDa polypeptide. Antibodies against a GST-ORF129 fusion protein were raised to establish that this 12 kDa polypeptide is the product of orf129. ORF129 was shown to accumulate in flower mitochondria as well as in root and leaf mitochondria. As for the CMS-associated protein (PCF protein) in petunia, ORF129 is primarily present in the matrix and is loosely associated with the inner mitochondrial membrane. The orf129 sequence was fused to a mitochondrial targeting pre-sequence, placed under the control of the Arabidopsis apetala3 promoter, and introduced into the tobacco nuclear genome. Transgenic expression of ORF129 resulted in male sterility, which provides clear supporting evidence that ORF129 is responsible for the male-sterile phenotype in sugar beet with wild beet cytoplasm.

  18. Discovery of a novel cytoplasmic male-sterility and its restorer lines in radish (Raphanus sativus L.).

    PubMed

    Lee, Young-Pyo; Park, Suhyung; Lim, Chaewan; Kim, Hyojung; Lim, Heerae; Ahn, Youngsoon; Sung, Soon-Kee; Yoon, Moo-Kyoung; Kim, Sunggil

    2008-10-01

    A male-sterile (MS) radish (Raphanus sativus L.) was found in an accession collected from Uzbekistan. Unlike Ogura MS radishes in which no pollen grain is typically visible during anthesis, a small number of pollen grains stuck together in the dehiscing anthers was observed in the newly identified MS radish. Fluorescein diacetate tests and scanning electron micrographs showed that pollen grains in the new MS radish were severely deformed and non-viable. Cytological examination of pollen development stages showed a clear difference in the defective stage from that seen in Ogura male-sterility. Reciprocal cross-pollination with diverse male-fertile lines indicated that pollen grains of the new MS radish were completely sterile, and the female organs were fully fertile. When the new MS radish and Ogura MS lines were cross-pollinated with a set of eight breeding lines, all F1 progeny originating from crosses with the new MS radish were male-sterile. In contrast, most of the F1 progeny resulting from crosses with Ogura MS lines were male-fertile. These results demonstrated that factors associated with induction of the newly identified male-sterility are different from those of Ogura male-sterility. The lack of restorer lines for the newly identified male-sterility led us to predict that it might be a complete cytoplasmic male-sterility without restorer-of-fertility genes in nuclear genomes. However, cross-pollination with more diverse radish germplasm identified one accession introduced from Russia that could completely restore fertility, proving the existence of restorer-of-fertility gene(s) for the new male-sterility. Meanwhile, the PCR amplification profile of molecular markers for the classification of radish mitochondrial genome types revealed that the new MS radish contained a novel mitotype.

  19. Female's courtship threshold allows intruding males to mate with reduced effort.

    PubMed

    Stoltz, J A; Andrade, M C B

    2010-02-22

    Female decision rules can influence the nature and intensity of sexual selection on males, but empirical demonstrations of rules underlying choice are rare. We hypothesized that female choice is largely based on a courtship duration threshold in the Australian redback spider (Latrodectus hasselti) because females kill males before copulation is complete (premature cannibalism) and reduce their paternity if courtship is brief. We used published data to infer that the female's threshold is approximately 100 min of courtship. We support this hypothesis by showing that premature cannibalism is common when the male's courtship duration is below this threshold, but is infrequent and unrelated to duration once courtship exceeds the threshold. We then ask whether females discriminate the source of courtship when rival males compete, as this will determine the effect of the threshold on male competitive tactics. We staged competitions where 'resident' males initially courted females in the absence of competition, exceeding the courtship threshold before 'intruding' males were introduced. Intruding males mated rapidly but were not prematurely cannibalized by females, in contrast to cases where competition starts before the threshold is surpassed. This suggests females do not distinguish which male satisfies the threshold, allowing intruders to parasitize the courtship efforts of residents. To our knowledge, such exploitation of mating efforts by rival males mediated by a female choice threshold has not been demonstrated elsewhere. Ironically, this female choice threshold and the attendant possibility of courtship parasitism may lead to selection for lower-quality males to recognize and seek out (rather than avoid) webs in which competitors are already present.

  20. Individual consistency in exploratory behaviour and mating tactics in male guppies

    NASA Astrophysics Data System (ADS)

    Kelley, Jennifer L.; Phillips, Samuel C.; Evans, Jonathan P.

    2013-10-01

    While behavioural plasticity is considered an adaptation to fluctuating social and environmental conditions, many animals also display a high level of individual consistency in their behaviour over time or across contexts (generally termed ‘personality’). However, studies of animal personalities that include sexual behaviour, or functionally distinct but correlated traits, are relatively scarce. In this study, we tested for individual behavioural consistency in courtship and exploratory behaviour in male guppies ( Poecilia reticulata) in two light environments (high vs. low light intensity). Based on previous work on guppies, we predicted that males would modify their behaviour from sneak mating tactics to courtship displays under low light conditions, but also that the rank orders of courtship effort would remain unchanged (i.e. highly sexually active individuals would display relatively high levels of courtship under both light regimes). We also tested for correlations between courtship and exploratory behaviour, predicting that males that had high display rates would also be more likely to approach a novel object. Although males showed significant consistency in their exploratory and mating behaviour over time (1 week), we found no evidence that these traits constituted a behavioural syndrome. Furthermore, in contrast to previous work, we found no overall effect of the light environment on any of the behaviours measured, although males responded to the treatment on an individual-level basis, as reflected by a significant individual-by-environment interaction. The future challenge is to investigate how individual consistency across different environmental contexts relates to male reproductive success.

  1. Quantifying mating success of territorial males and sneakers in a bower-building cichlid fish.

    PubMed

    Magalhaes, I S; Smith, A M; Joyce, D A

    2017-01-27

    The strategies and traits males evolve to mate with females are incredible in their diversity. Theory on the evolution of secondary sexual characters suggests that evolving any costly trait or strategy will pay off and stabilise in the population if it is advantageous compared to the alternative less costly strategy, but quantifying the relative success of the two can be difficult. In Lake Malawi, Africa, there are >200 species of cichlid fish in which the males form leks and spend several weeks per year building sand-castle "bowers" several times their size. We tested the idea that a less costly "sneaking" strategy could be successful by quantifying the mating success of bower-holding versus non-bower-holding males. We PIT-tagged every fish in a semi-natural experimental set-up and placed tag-readers on the side of bowers to determine which fish held a bower. We then genotyped the eggs removed from females' mouths to assign paternity of each egg. Broods were fathered by up to 3 different males. Although paternity was mostly assigned to males that held a bower, a small number of males who did not own a bower were more successful than some of those that did, indicating a role for an alternative strategy in these bower builders.

  2. Love is blind: indiscriminate female mating responses to male courtship pheromones in newts (Salamandridae).

    PubMed

    Treer, Dag; Van Bocxlaer, Ines; Matthijs, Severine; Du Four, Dimitri; Janssenswillen, Sunita; Willaert, Bert; Bossuyt, Franky

    2013-01-01

    Internal fertilization without copulation or prolonged physical contact is a rare reproductive mode among vertebrates. In many newts (Salamandridae), the male deposits a spermatophore on the substrate in the water, which the female subsequently takes up with her cloaca. Because such an insemination requires intense coordination of both sexes, male newts have evolved a courtship display, essentially consisting of sending pheromones under water by tail-fanning towards their potential partner. Behavioral experiments until now mostly focused on an attractant function, i.e. showing that olfactory cues are able to bring both sexes together. However, since males start their display only after an initial contact phase, courtship pheromones are expected to have an alternative function. Here we developed a series of intraspecific and interspecific two-female experiments with alpine newt (Ichthyosaura alpestris) and palmate newt (Lissotriton helveticus) females, comparing behavior in male courtship water and control water. We show that male olfactory cues emitted during tail-fanning are pheromones that can induce all typical features of natural female mating behavior. Interestingly, females exposed to male pheromones of their own species show indiscriminate mating responses to conspecific and heterospecific females, indicating that visual cues are subordinate to olfactory cues during courtship.

  3. Quantifying mating success of territorial males and sneakers in a bower-building cichlid fish

    PubMed Central

    Magalhaes, I. S.; Smith, A. M.; Joyce, D. A.

    2017-01-01

    The strategies and traits males evolve to mate with females are incredible in their diversity. Theory on the evolution of secondary sexual characters suggests that evolving any costly trait or strategy will pay off and stabilise in the population if it is advantageous compared to the alternative less costly strategy, but quantifying the relative success of the two can be difficult. In Lake Malawi, Africa, there are >200 species of cichlid fish in which the males form leks and spend several weeks per year building sand-castle “bowers” several times their size. We tested the idea that a less costly “sneaking” strategy could be successful by quantifying the mating success of bower-holding versus non-bower-holding males. We PIT-tagged every fish in a semi-natural experimental set-up and placed tag-readers on the side of bowers to determine which fish held a bower. We then genotyped the eggs removed from females’ mouths to assign paternity of each egg. Broods were fathered by up to 3 different males. Although paternity was mostly assigned to males that held a bower, a small number of males who did not own a bower were more successful than some of those that did, indicating a role for an alternative strategy in these bower builders. PMID:28128313

  4. Male-specific (Z)-9-tricosene stimulates female mating behaviour in the spider Pholcus beijingensis

    PubMed Central

    Xiao, Yong-Hong; Zhang, Jian-Xu; Li, Shu-Qiang

    2010-01-01

    Chemical signals play an important role in spider sexual communication, yet the chemistry of spider sex pheromones remains poorly understood. Chemical identification of male-produced pheromone-mediating sexual behaviour in spiders has also, to our knowledge, not been reported before. This study aimed to examine whether chemically mediated strategies are used by males of the spider Pholcus beijingensis for increasing the probability of copulation. Based on data from gas chromatography–mass spectrometry analysis, electroantennography assay and a series of behavioural tests, we verified that (Z)-9-tricosene is a male-specific compound in the spider P. beijingensis. This compound acts as an aphrodisiac: it increases the likelihood that a female will mate. Mate-searching males release (Z)-9-tricosene to stimulate sexual behaviour of conspecific females. In the two-choice assay, however, sexually receptive females show no preference to the chambers containing (Z)-9-tricosene. This indicates that the male pheromone of P. beijingensis is not an attractant per se to the conspecific females. This is, to our knowledge, the first identification of a male-produced aphrodisiac pheromone in spiders. PMID:20462911

  5. Individual consistency in exploratory behaviour and mating tactics in male guppies.

    PubMed

    Kelley, Jennifer L; Phillips, Samuel C; Evans, Jonathan P

    2013-10-01

    While behavioural plasticity is considered an adaptation to fluctuating social and environmental conditions, many animals also display a high level of individual consistency in their behaviour over time or across contexts (generally termed 'personality'). However, studies of animal personalities that include sexual behaviour, or functionally distinct but correlated traits, are relatively scarce. In this study, we tested for individual behavioural consistency in courtship and exploratory behaviour in male guppies (Poecilia reticulata) in two light environments (high vs. low light intensity). Based on previous work on guppies, we predicted that males would modify their behaviour from sneak mating tactics to courtship displays under low light conditions, but also that the rank orders of courtship effort would remain unchanged (i.e. highly sexually active individuals would display relatively high levels of courtship under both light regimes). We also tested for correlations between courtship and exploratory behaviour, predicting that males that had high display rates would also be more likely to approach a novel object. Although males showed significant consistency in their exploratory and mating behaviour over time (1 week), we found no evidence that these traits constituted a behavioural syndrome. Furthermore, in contrast to previous work, we found no overall effect of the light environment on any of the behaviours measured, although males responded to the treatment on an individual-level basis, as reflected by a significant individual-by-environment interaction. The future challenge is to investigate how individual consistency across different environmental contexts relates to male reproductive success.

  6. Defining the Genetic Architecture Underlying Female- and Male-Mediated Nonrandom Mating and Seed Yield Traits in Arabidopsis1[OA

    PubMed Central

    Carlson, Ann Louise; Fitz Gerald, Jonathan Nesbit; Telligman, Megan; Roshanmanesh, Jacob; Swanson, Robert John

    2011-01-01

    Postpollination nonrandom mating among compatible mates is a widespread phenomenon in plants and is genetically undefined. In this study, we used the recombinant inbred line (RIL) population between Landsberg erecta and Columbia (Col) accessions of Arabidopsis (Arabidopsis thaliana) to define the genetic architecture underlying both female- and male-mediated nonrandom mating traits. To map the genetic loci responsible for male-mediated nonrandom mating, we performed mixed pollinations with Col and RIL pollen on Col pistils. To map the genetic loci responsible for female-mediated nonrandom mating, we performed mixed pollinations with Col and Landsberg erecta pollen on RIL pistils. With these data, we performed composite interval mapping to identify two quantitative trait loci (QTLs) that control male-mediated nonrandom mating. We detected epistatic interactions between these two loci. We also explored female- and male-mediated traits involved in seed yield in mixed pollinations. We detected three female QTLs and one male QTL involved in directing seed number per fruit. To our knowledge, the results of these experiments represent the first time the female and male components of seed yield and nonrandom mating have been separately mapped. PMID:22007025

  7. Female discrimination thresholds frequently exceed local male display variation: implications for mate choice dynamics and sexual selection.

    PubMed

    Höbel, G

    2016-03-01

    Among the factors that can influence female mate choice decisions is the degree to which females differentiate among similar displays: as differences decrease, females are expected to eventually stop discriminating. This discrimination threshold, in conjunction with the magnitude of male trait variation females regularly encounter while making mate choice decisions, may have important consequences for sexual selection. If local display variation is above the discrimination threshold, female preferences should translate into higher mating success for the more attractive male. But if display variation is frequently below the threshold, the resulting increased pattern of random mating may obscure the existence of female mate choice. I investigated the interplay between female discrimination and male display variation in green treefrogs (Hyla cinerea) and found that call trait differences between nearest neighbour males were frequently smaller than what females are expected to discriminate. This finding has two important consequences for our understanding of sexual selection in the wild: first, low display variation should weaken the strength of selection on male display traits, but the direction of selection should mirror the one predicted from females choice trials. Second, caution is needed when interpreting data on realized mating success in the wild: a pattern of random mating with respect to male display traits does not always mean that female preferences are weak or that conditions are too challenging for females to express their preferences. Rather, insufficient display variation can generate the same pattern.

  8. The Propensity of Pentatricopeptide Repeat Genes to Evolve into Restorers of Cytoplasmic Male Sterility

    PubMed Central

    Gaborieau, Lydiane; Brown, Gregory G.; Mireau, Hakim

    2016-01-01

    Cytoplasmic male sterility (CMS) is a widespread phenotype in plants, which present a defect in the production of functional pollen. The male sterilizing factors usually consist of unusual genes or open reading frames encoded by the mitochondrial genome. CMS can be suppressed by specific nuclear genes called restorers of fertility (Rfs). In the majority of cases, Rf genes produce proteins that act directly on the CMS conferring mitochondrial transcripts by binding them specifically and promoting processing events. In this review, we explore the wide array of mechanisms guiding fertility restoration. PPR proteins represent the most frequent protein class among identified Rfs and they exhibit ideal characteristics to evolve into restorer of fertility when the mechanism of restoration implies a post-transcriptional action. Here, we review the literature that highlights those characteristics and help explain why PPR proteins are ideal for the roles they play as restorers of fertility. PMID:27999582

  9. Programmed cell death promotes male sterility in the functional dioecious Opuntia stenopetala (Cactaceae)

    PubMed Central

    Flores-Rentería, Lluvia; Orozco-Arroyo, Gregorio; Cruz-García, Felipe; García-Campusano, Florencia; Alfaro, Isabel; Vázquez-Santana, Sonia

    2013-01-01

    Background and Aims The sexual separation in dioecious species has interested biologists for decades; however, the cellular mechanism leading to unisexuality has been poorly understood. In this study, the cellular changes that lead to male sterility in the functionally dioecious cactus, Opuntia stenopetala, are described. Methods The spatial and temporal patterns of programmed cell death (PCD) were determined in the anthers of male and female flowers using scanning electron microscopy analysis and histological observations, focusing attention on the transition from bisexual to unisexual development. In addition, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling assays were used as an indicator of DNA fragmentation to corroborate PCD. Key results PCD was detected in anthers of both female and male flowers, but their patterns differed in time and space. Functionally male individuals developed viable pollen, and normal development involved PCD on each layer of the anther wall, which occurred progressively from the inner (tapetum) to the outer layer (epidermis). Conversely, functional female individuals aborted anthers by premature and displaced PCD. In anthers of female flowers, the first signs of PCD, such as a nucleus with irregular shape, fragmented and condensed chromatin, high vacuolization and condensed cytoplasm, occurred at the microspore mother cell stage. Later these features were observed simultaneously in all anther wall layers, connective tissue and filament. Neither pollen formation nor anther dehiscence was detected in female flowers of O. stenopetala due to total anther disruption. Conclusions Temporal and spatial changes in the patterns of PCD are responsible for male sterility of female flowers in O. stenopetala. Male fertility requires the co-ordination of different events, which, when altered, can lead to male sterility and to functionally unisexual individuals. PCD could be a widespread mechanism in the determination of

  10. Variation in Male Fertilities and Pairwise Mating Probabilities in Picea glauca

    PubMed Central

    Schoen, D. J.; Stewart, S. C.

    1987-01-01

    Frequencies of multilocus male gametes in seeds collected from clones in several blocks of a white spruce seed orchard were analyzed as part of a 2-yr study of mating system variation in this species. Observed frequencies of male gamete types departed significantly from those expected assuming equal male fertilities among clones. Male gamete frequencies in seed crops were significantly heterogeneous among clones within blocks, and among blocks within clones. Clonal male fertilities were estimated from male gamete frequency data. These estimates were highly skewed, with a small proportion of the clones contributing male gametes to the majority of the seed. The estimates were significantly heterogeneous among clones within blocks, and among blocks within clones. Between-year variation in clonal male fertilities was also pronounced, with male fertilities of some clones changing by as much as three orders of magnitude. Clonal male fertility was significantly correlated with clonal male cone production in both years. These results are important with regard to assumptions made for the estimation of general combining ability, average genetic correlation among progeny from single parents, and expected response to selection in open-pollinated plant populations. PMID:17246377

  11. Visual Adaptations for Mate Detection in the Male Carpenter Bee Xylocopa tenuiscapa.

    PubMed

    Somanathan, Hema; Borges, Renee Maria; Warrant, Eric J; Kelber, Almut

    2017-01-01

    Sexual dimorphism in eye structure is attributed to sexual selection in animals that employ vision for locating mates. In many male insects, large eyes and eye regions of higher acuity are believed to facilitate the location of females. Here, we compare various features of male and female eyes in three sympatric carpenter bee species, which include two diurnal species (Xylocopa tenuiscapa and X. leucothorax) as well as a nocturnal species (X. tranquebarica). In X. tenuiscapa, males have larger eyes than females, while in the nocturnal X. tranquebarica, males have slightly smaller eyes and in X. leucothorax, the eyes are of similar size in both sexes. X. tenuiscapa males detect females by perching near nest sites (resource defence) or along fly-ways and other open areas with good visibility. Males of the other two species search for females by patrolling. We postulate that the larger eyes of male X. tenuiscapa are beneficial to their mode of mate detection since perching males may benefit from a larger visual area of high resolution detecting moving stimuli across the sky, and which may be germane to the more social and gregarious nesting behaviour of this species, compared to the other solitary bees. We tested the performance of the eyes of male X. tenuiscapa behaviourally and find that a perching male can detect a flying female at a distance of 20 m, which darkens the visual field of a single ommatidium by just 2%. This, together with the bee's high spatial resolution permits detection of moving stimuli at least as well or even better than achieved by honey bee drones.

  12. Visual Adaptations for Mate Detection in the Male Carpenter Bee Xylocopa tenuiscapa

    PubMed Central

    Somanathan, Hema; Borges, Renee Maria; Warrant, Eric J.; Kelber, Almut

    2017-01-01

    Sexual dimorphism in eye structure is attributed to sexual selection in animals that employ vision for locating mates. In many male insects, large eyes and eye regions of higher acuity are believed to facilitate the location of females. Here, we compare various features of male and female eyes in three sympatric carpenter bee species, which include two diurnal species (Xylocopa tenuiscapa and X. leucothorax) as well as a nocturnal species (X. tranquebarica). In X. tenuiscapa, males have larger eyes than females, while in the nocturnal X. tranquebarica, males have slightly smaller eyes and in X. leucothorax, the eyes are of similar size in both sexes. X. tenuiscapa males detect females by perching near nest sites (resource defence) or along fly-ways and other open areas with good visibility. Males of the other two species search for females by patrolling. We postulate that the larger eyes of male X. tenuiscapa are beneficial to their mode of mate detection since perching males may benefit from a larger visual area of high resolution detecting moving stimuli across the sky, and which may be germane to the more social and gregarious nesting behaviour of this species, compared to the other solitary bees. We tested the performance of the eyes of male X. tenuiscapa behaviourally and find that a perching male can detect a flying female at a distance of 20 m, which darkens the visual field of a single ommatidium by just 2%. This, together with the bee’s high spatial resolution permits detection of moving stimuli at least as well or even better than achieved by honey bee drones. PMID:28107354

  13. Individual Pheromone Signature in Males: Prerequisite for Pheromone-Mediated Mate Assessment in the Central American Locust, Schistocerca Piceifrons.

    PubMed

    Stahr, Christiane; Seidelmann, Karsten

    2016-12-01

    Living in high-density groups of animals has advantages and disadvantages for mating. The advantage of facilitated mate finding is compromised by difficulties in protecting a suitable partner from competitors. Thus, males regularly are faced with increased competition for sperm, and females with harassment by males at high population densities. To cope with these problems, mating tactics and mate choice mechanisms have to be adjusted. An adaptation to gregarious condition observed in locusts includes the use of male-emitted pheromones. Males of the Central American locust, Schistocerca piceifrons, release sex-specific volatiles, which were identified as phenethyl alcohol (synonym: phenyl-ethyl-alcohol, 2-phenyl-1-ethanol, 2-phenylethanol, PEA), (Z)-3-nonen-1-ol (3-Nol), and (Z)-2-octen-1-ol (2-Ool). The emission of the two major compounds, PEA and 3-Nol, was restricted to crowded conditions. Furthermore, the release of both volatiles was coupled to males reaching sexual maturity, indicating a function in reproductive behavior. However, neither the single substances nor their mixtures were attractive or repellent to the locusts. Instead, females prefer the sperm of high pheromone-emitting males to fertilize their ova. In this way, the male-specific volatiles act as mate assessment pheromones utilized in a context of cryptic female choice. This function is well supported by the highly variable but individual-specific emission rates of the three compounds. Schistocerca piceifrons males release a virtually unique personal pheromone signature, a prerequisite for mate assessment pheromones.

  14. Variable male potential rate of reproduction: high male mating capacity as an adaptation to parasite-induced excess of females?

    PubMed Central

    Moreau, Jérôme; Rigaud, Thierry

    2003-01-01

    Numerous animals are known to harbour intracytoplasmic symbionts that gain transmission to a new host generation via female eggs and not male sperm. Bacteria of the genus Wolbachia are a typical example. They infect a large range of arthropod species and manipulate host reproduction in several ways. In terrestrial isopods (woodlice), Wolbachia are responsible for converting males into females (feminization (F)) in some species, or for infertility in certain host crosses in other species (cytoplasmic incompatibility (CI)). Wolbachia with the F phenotype impose a strong excess of females on their host populations, while Wolbachia expressing CI do not. Here, we test the possibility that male mating capacity (MC) is correlated with Wolbachia-induced phenotype. We show that males of isopod hosts harbouring F Wolbachia possess a strong MC (i.e. are able to mate with several females in a short time), while those of species harbouring CI Wolbachia possess a weaker MC. This pattern may be explained either by the selection of high MC following the increase in female-biased sex ratios, or because the F phenotype would lead to population extinction in species where MC is not sufficiently high. This last hypotheses is nevertheless more constrained by population structure. PMID:12965021

  15. Sex Ratio Meiotic Drive as a Plausible Evolutionary Mechanism for Hybrid Male Sterility

    PubMed Central

    Zhang, Linbin; Xiao, Hailian; Tao, Yun

    2015-01-01

    Biological diversity on Earth depends on the multiplication of species or speciation, which is the evolution of reproductive isolation such as hybrid sterility between two new species. An unsolved puzzle is the exact mechanism(s) that causes two genomes to diverge from their common ancestor so that some divergent genes no longer function properly in the hybrids. Here we report genetic analyses of divergent genes controlling male fertility and sex ratio in two very young fruitfly species, Drosophila albomicans and D. nasuta. A majority of the genetic divergence for both traits is mapped to the same regions by quantitative trait loci mappings. With introgressions, six major loci are found to contribute to both traits. This genetic colocalization implicates that genes for hybrid male sterility have evolved primarily for controlling sex ratio. We propose that genetic conflicts over sex ratio may operate as a perpetual dynamo for genome divergence. This particular evolutionary mechanism may largely contribute to the rapid evolution of hybrid male sterility and the disproportionate enrichment of its underlying genes on the X chromosome – two patterns widely observed across animals. PMID:25822261

  16. Taurine enhances the sexual response and mating ability in aged male rats.

    PubMed

    Yang, Jiancheng; Lin, Shumei; Feng, Ying; Wu, Gaofeng; Hu, Jianmin

    2013-01-01

    It has been demonstrated that taurine is abundant in male reproductive organs, and can be biosynthesized by testis, but the taurine concentration will reduce with aging. The levels of serum LH, T, NOS, and NO were found to be obviously increased by taurine supplementation in aged rats in our previous study. In addition, aging will result in a significant decline in sexual response and function, which may be attributed to the androgen deficiency. Furthermore, NO has been proposed as a crucial mediator of penile erection. That makes us hypothesize that there is potential relationship between taurine decline and erection dysfunction in aged males. So the primary aim of the present study was to investigate the effect of taurine on male sexuality in rats. Taurine was offered in water to male aged (20 months old) rats for 110 days. The effects of taurine on the sexual response, mating ability, levels of serum reproductive hormones, and penile NOS and NO levels were investigated. The results showed that taurine can significantly reduce the EL and ML; obviously increase the ERF, MF, IF, and EJF; stimulate the secretion of GnRH, LH, and T; and elevate penis NOS and NO level in aged rats. The results indicated that taurine can enhance the sexual response and mating ability in aged male rats by increasing the level of testosterone and NO, but the exact mechanism of which needs to be further investigated.

  17. cdc-25.4, a Caenorhabditis elegans Ortholog of cdc25, Is Required for Male Mating Behavior.

    PubMed

    Oh, Sangmi; Kawasaki, Ichiro; Park, Jae-Hyung; Shim, Yhong-Hee

    2016-12-07

    Cell division cycle 25 (cdc25) is an evolutionarily conserved phosphatase that promotes cell cycle progression. Among the four cdc25 orthologs in Caenorhabditis elegans, we found that cdc-25.4 mutant males failed to produce outcrossed progeny. This was not caused by defects in sperm development, but by defects in male mating behavior. The cdc-25.4 mutant males showed various defects during male mating, including contact response, backing, turning, and vulva location. Aberrant turning behavior was the most prominent defect in the cdc-25.4 mutant males. We also found that cdc-25.4 is expressed in many neuronal cells throughout development. The turning defect in cdc-25.4 mutant males was recovered by cdc-25.4 transgenic expression in neuronal cells, suggesting that cdc-25.4 functions in neurons for male mating. However, the neuronal morphology of cdc-25.4 mutant males appeared to be normal, as examined with several neuronal markers. Also, RNAi depletion of wee-1.3, a C. elegans ortholog of Wee1/Myt1 kinase, failed to suppress the mating defects of cdc-25.4 mutant males. These findings suggest that, for successful male mating, cdc-25.4 does not target cell cycles that are required for neuronal differentiation and development. Rather, cdc-25.4 likely regulates noncanonical substrates in neuronal cells.

  18. cdc-25.4, a Caenorhabditis elegans Ortholog of cdc25, Is Required for Male Mating Behavior

    PubMed Central

    Oh, Sangmi; Kawasaki, Ichiro; Park, Jae-Hyung; Shim, Yhong-Hee

    2016-01-01

    Cell division cycle 25 (cdc25) is an evolutionarily conserved phosphatase that promotes cell cycle progression. Among the four cdc25 orthologs in Caenorhabditis elegans, we found that cdc-25.4 mutant males failed to produce outcrossed progeny. This was not caused by defects in sperm development, but by defects in male mating behavior. The cdc-25.4 mutant males showed various defects during male mating, including contact response, backing, turning, and vulva location. Aberrant turning behavior was the most prominent defect in the cdc-25.4 mutant males. We also found that cdc-25.4 is expressed in many neuronal cells throughout development. The turning defect in cdc-25.4 mutant males was recovered by cdc-25.4 transgenic expression in neuronal cells, suggesting that cdc-25.4 functions in neurons for male mating. However, the neuronal morphology of cdc-25.4 mutant males appeared to be normal, as examined with several neuronal markers. Also, RNAi depletion of wee-1.3, a C. elegans ortholog of Wee1/Myt1 kinase, failed to suppress the mating defects of cdc-25.4 mutant males. These findings suggest that, for successful male mating, cdc-25.4 does not target cell cycles that are required for neuronal differentiation and development. Rather, cdc-25.4 likely regulates noncanonical substrates in neuronal cells. PMID:27770028

  19. Radiation-induced metabolomic changes in sterile male Μοnochamus alternatus (Coleoptera: Cerambycidae).

    PubMed

    Qu, L J; Wang, L J; Zhang, Y A; Wang, Q H; Wang, Y Z; Zhao, T H; Cai, W Z

    2014-01-01

    Radiation-induced sterile insect technique is a biologically based, environment-friendly method for the suppression or eradication of a number of insect pests. Although the basic mechanisms underlying the technology have been well studied, little is known about the cell responses in organisms. Characterization of the metabolic shift associated with radiation exposure in sterile insects would be helpful for understanding the detailed mechanism underlying this technique and promote its practical application. In this article, a metabolomic study was performed to characterize the global metabolic changes induced by radiation using untreated and 40 Gy (60)Coγ-irradiated testes of Japanese pine sawyer, Monochamus alternatus Hope. Differential metabolites were detected and tentatively identified. Many key metabolites in glycolysis and the tricarboxylic acid cycle, as well as most fatty and amino acids, were elevated in irradiated male M. alternatus, presumably resulting from depression of glycolysis and the tricarboxylic acid cycle, each of which are important pathways for energy generation Adenosine Triphosphate (ATP) in insect spermatozoa. The findings in this article will contribute to our knowledge of the characteristic metabolic changes associated with irradiation sterility and understand the molecular mechanisms underlying radiation-induced sterile insect technique.

  20. Energetic costs of male reproduction in a scramble competition mating system.

    PubMed

    Lane, Jeffrey E; Boutin, Stan; Speakman, John R; Humphries, Murray M

    2010-01-01

    1. The assumption that the primary limitations on reproductive success differ between the sexes is inherent in traditional sexual selection theory. Although the energy that can be allocated to reproduction is assumed to be the main limitation to females, the ability to attract and defend oestrous females is assumed to be the primary limitation to males. 2. Estimates of the energetic costs of reproduction in male mammals are, however, limited and have largely been obtained from sexually dimorphic species exhibiting female defence mating systems. These studies often reveal that the energetic cost of male reproduction is similar to or even exceeds that of females, and therefore challenge long-held assumptions of inter-sexual reproductive limitations, but their generality is little known. 3. We coupled measurements of energy expenditure with detailed behavioural observations of reproductive male North American red squirrels (Tamiasciurus hudsonicus). This species displays minimal sexual dimorphism and exhibits a scramble competition mating system, under which sexual selection favours enhanced mate searching effort by males. 4. We conducted the study over 2 years characterized by a substantial variation in upcoming natural food availability and across two study populations that experienced either natural food abundance or an ad libitum food-supplementation to investigate the influence of resource availability on male reproductive energy expenditure. 5. Under natural conditions, mean energy expenditure of males across the 2 years was high, approximating that of females during lactation. Furthermore, in the anticipation of high upcoming natural food availability and resultant offspring survival, expenditure approximately doubled (from 290 +/- 7 to 579 +/- 73 kJ day(-1)). When current food availability (and consequently the density of receptive females) was experimentally elevated, males displayed the highest levels of energy expenditure we recorded (873 +/- 98 kJ day(-1

  1. Simple Y-autosomal incompatibilities cause hybrid male sterility in reciprocal crosses between Drosophila virilis and D. americana.

    PubMed

    Sweigart, Andrea L

    2010-03-01

    Postzygotic reproductive isolation evolves when hybrid incompatibilities accumulate between diverging populations. Here, I examine the genetic basis of hybrid male sterility between two species of Drosophila, Drosophila virilis and D. americana. From these analyses, I reach several conclusions. First, neither species carries any autosomal dominant hybrid male sterility alleles: reciprocal F(1) hybrid males are perfectly fertile. Second, later generation (backcross and F(2)) hybrid male sterility between D. virilis and D. americana is not polygenic. In fact, I identified only three genetically independent incompatibilities that cause hybrid male sterility. Remarkably, each of these incompatibilities involves the Y chromosome. In one direction of the cross, the D. americana Y is incompatible with recessive D. virilis alleles at loci on chromosomes 2 and 5. In the other direction, the D. virilis Y chromosome causes hybrid male sterility in combination with recessive D. americana alleles at a single QTL on chromosome 5. Finally, in contrast with findings from other Drosophila species pairs, the X chromosome has only a modest effect on hybrid male sterility between D. virilis and D. americana.

  2. The PSI–U1 snRNP interaction regulates male mating behavior in Drosophila

    PubMed Central

    Wang, Qingqing; Taliaferro, J. Matthew; Klibaite, Ugne; Hilgers, Valérie; Shaevitz, Joshua W.; Rio, Donald C.

    2016-01-01

    Alternative pre-mRNA splicing (AS) is a critical regulatory mechanism that operates extensively in the nervous system to produce diverse protein isoforms. Fruitless AS isoforms have been shown to influence male courtship behavior, but the underlying mechanisms are unknown. Using genome-wide approaches and quantitative behavioral assays, we show that the P-element somatic inhibitor (PSI) and its interaction with the U1 small nuclear ribonucleoprotein complex (snRNP) control male courtship behavior. PSI mutants lacking the U1 snRNP-interacting domain (PSIΔAB mutant) exhibit extended but futile mating attempts. The PSIΔAB mutant results in significant changes in the AS patterns of ∼1,200 genes in the Drosophila brain, many of which have been implicated in the regulation of male courtship behavior. PSI directly regulates the AS of at least one-third of these transcripts, suggesting that PSI–U1 snRNP interactions coordinate the behavioral network underlying courtship behavior. Importantly, one of these direct targets is fruitless, the master regulator of courtship. Thus, PSI imposes a specific mode of regulatory control within the neuronal circuit controlling courtship, even though it is broadly expressed in the fly nervous system. This study reinforces the importance of AS in the control of gene activity in neurons and integrated neuronal circuits, and provides a surprising link between a pleiotropic pre-mRNA splicing pathway and the precise control of successful male mating behavior. PMID:27114556

  3. Selection and characterization of a novel photoperiod-sensitive male sterile line in upland cotton.

    PubMed

    Ma, Jianhui; Wei, Hengling; Liu, Ji; Song, Meizhen; Pang, Chaoyou; Wang, Long; Zhang, Wenxiang; Fan, Shuli; Yu, Shuxun

    2013-07-01

    Upland cotton (Gossypium hirsutum L.) shows strong heterosis. However, heterosis is not widely utilized owing to the high cost of hybrid seed production. Creation of a photoperiod-sensitive genetic male sterile line could substantially reduce the cost of hybrid seed production in upland cotton. Such a mutant with virescent marker was found by space mutation in near-earth orbit and its traits had been stable after 4 years of selection in Anyang and Sanya, China. This mutant was fertile with an 11-12.5 h photoperiod when the temperature was higher than 21.5 °C and was sterile with a 13-14.5 h photoperiod. Genetic analysis indicated that both traits were controlled by a single recessive gene or two closely linked genes. Also, the cytological observations and transcriptome profiling analysis showed that the degradation of pollen grain cytoplasm should be the primary reason why the mutant line were male sterile under long-day conditions.

  4. The Effects of Interspecific Courtship on the Mating Success of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) Males

    PubMed Central

    Bargielowski, Irka; Blosser, Erik; Lounibos, L. P.

    2015-01-01

    Satyrization, a form of asymmetric reproductive interference, has recently been shown to play a role in competitive displacements of Aedes aegypti (L.) by Aedes albopictus (Skuse). Furthermore, female Ae. aegypti from populations in sympatry with Ae. albopictus have evolved reproductive character displacement and changes in mating behavior to reduce interspecific mating. In this article, we examine evolutionary responses of males to interspecific mating and show that satyrization has also evoked reproductive character displacement in males. We demonstrate that the presence of heterospecific females negatively influences conspecific mating success in male Ae. aegypti, most likely due to misdirected courting or mating efforts, and that males of this species from populations in sympatry with Ae. albopictus have evolved to be less influenced by the presence of heterospecific females than their allopatric counterparts. Conversely, we suggest that the presence of conspecifics may, in some circumstances, increase interspecific mating. This study demonstrates that co-occurrences of these two invasive species may lead to evolution and adaptation of reproductive behaviors to changing circumstances. Understanding the processes driving development of mate choice preferences or avoidance mechanisms may help predict future changes in the distribution and abundance of insect vectors or pests. PMID:27418696

  5. Cytoplasmic effects on DNA methylation between male sterile lines and the maintainer in wheat (Triticum aestivum L.).

    PubMed

    Ba, Qingsong; Zhang, Gaisheng; Niu, Na; Ma, Shoucai; Wang, Junwei

    2014-10-01

    Male sterile cytoplasm plays an important role in hybrid wheat, and three-line system including male sterile (A line), its maintainer (B line) and restoring (R line) has played a major role in wheat hybrid production. It is well known that DNA methylation plays an important role in gene expression regulation during biological development in wheat. However, no reports are available on DNA methylation affected by different male sterile cytoplasms in hybrid wheat. We employed a methylation-sensitive amplified polymorphism technique to characterize nuclear DNA methylation in three male sterile cytoplasms. A and B lines share the same nucleus, but have different cytoplasms which is male sterile for the A and fertile for the B. The results revealed a relationship of DNA methylation at these sites specifically with male sterile cytoplasms, as well as male sterility, since the only difference between the A lines and B line was the cytoplasm. The DNA methylation was markedly affected by male sterile cytoplasms. K-type cytoplasm affected the methylation to a much greater degree than T-type and S-type cytoplasms, as indicated by the ratio of methylated sites, ratio of fully methylated sites, and polymorphism between A lines and B line for these cytoplasms. The genetic distance between the cytoplasm and nucleus for the K-type is much greater than for the T- and S-types because the former is between Aegilops genus and Triticum genus and the latter is within Triticum genus between Triticum spelta and Triticum timopheevii species. Thus, this difference in genetic distance may be responsible for the variation in methylation that we observed.

  6. Pest persistence and eradication conditions in a deterministic model for sterile insect release.

    PubMed

    Gordillo, Luis F

    2015-01-01

    The release of sterile insects is an environment friendly pest control method used in integrated pest management programmes. Difference or differential equations based on Knipling's model often provide satisfactory qualitative descriptions of pest populations subject to sterile release at relatively high densities with large mating encounter rates, but fail otherwise. In this paper, I derive and explore numerically deterministic population models that include sterile release together with scarce mating encounters in the particular case of species with long lifespan and multiple matings. The differential equations account separately the effects of mating failure due to sterile male release and the frequency of mating encounters. When insects spatial spread is incorporated through diffusion terms, computations reveal the possibility of steady pest persistence in finite size patches. In the presence of density dependence regulation, it is observed that sterile release might contribute to induce sudden suppression of the pest population.

  7. The synthetic progestogen, Levonorgestrel, but not natural progesterone, affects male mate calling behavior of Xenopus laevis.

    PubMed

    Hoffmann, Frauke; Kloas, Werner

    2012-05-01

    Worldwide, more than 100 million women use hormonal contraceptives, which act through progestogenic modes of action. These man-made hormones can enter the aquatic environment as they are excreted via feces and urine. Xeno-progestins are able to interfere with the endocrine system of female aquatic vertebrates impairing oogenesis and reproduction. However, data on progestogenic effects on reproductive behavior of male aquatic vertebrates are lacking. To evaluate whether progestins affect the mating behavior of male Xenopus laevis, we exposed male frogs to three environmentally relevant concentrations (10(-7) M, 10(-8) M and 10(-10) M) of the synthetic progestin Levonorgestrel (LNG) and the corresponding natural steroid progesterone (PRG), respectively. LNG at all exposure concentrations increased the proportions of advertisement calling, indicating a sexually aroused state of the males. Furthermore LNG at 10(-7) M decreased the relative proportions of rasping, a call type indicating a sexually unaroused state of the male. PRG, on the other hand, did not affect any of those parameters. Temporal and spectral features of the advertisement call itself were not affected by any of the two exposure treatments. Since LNG exhibits slight androgenic activity, the results suggest that LNG effects on male mate calling behavior of X. laevis are due to its moderate androgenic but not to its progestogenic activities. However, although males' sexual arousal seems to be enhanced by LNG, the adverse effects of LNG on female reproduction presumably outweigh these enhancing effects and LNG exposure nonetheless might result in reduced reproductive success of these animals.

  8. Costs of mating competition limit male lifetime breeding success in polygynous mammals

    PubMed Central

    Lukas, Dieter; Clutton-Brock, Tim

    2014-01-01

    Although differences in breeding lifespan are an important source of variation in male fitness, the factors affecting the breeding tenure of males have seldom been explored. Here, we use cross-species comparisons to investigate the correlates of breeding lifespan in male mammals. Our results show that male breeding lifespan depends on the extent of polygyny, which reflects the relative intensity of competition for access to females. Males have relatively short breeding tenure in species where individuals have the potential to monopolize mating with multiple females, and longer ones where individuals defend one female at a time. Male breeding tenure is also shorter in species in which females breed frequently than in those where females breed less frequently, suggesting that the costs of guarding females may contribute to limiting tenure length. As a consequence of these relationships, estimates of skew in male breeding success within seasons overestimate skew calculated across the lifetime and, in several polygynous species, variance in lifetime breeding success is not substantially higher in males than in females. PMID:24827443

  9. Costs of mating competition limit male lifetime breeding success in polygynous mammals.

    PubMed

    Lukas, Dieter; Clutton-Brock, Tim

    2014-07-07

    Although differences in breeding lifespan are an important source of variation in male fitness, the factors affecting the breeding tenure of males have seldom been explored. Here, we use cross-species comparisons to investigate the correlates of breeding lifespan in male mammals. Our results show that male breeding lifespan depends on the extent of polygyny, which reflects the relative intensity of competition for access to females. Males have relatively short breeding tenure in species where individuals have the potential to monopolize mating with multiple females, and longer ones where individuals defend one female at a time. Male breeding tenure is also shorter in species in which females breed frequently than in those where females breed less frequently, suggesting that the costs of guarding females may contribute to limiting tenure length. As a consequence of these relationships, estimates of skew in male breeding success within seasons overestimate skew calculated across the lifetime and, in several polygynous species, variance in lifetime breeding success is not substantially higher in males than in females.

  10. Quality of Sterile Male Tsetse after Long Distance Transport as Chilled, Irradiated Pupae

    PubMed Central

    Bassene, Mireille D.; Fall, Assane Gueye; Diouf, Thérèse A. R.; Sall, Baba; Vreysen, Marc J. B.; Rayaissé, Jean-Baptiste; Takac, Peter; Sidibé, Issa; Parker, Andrew G.; Mutika, Gratian N.; Bouyer, Jérémy; Gimonneau, Geoffrey

    2015-01-01

    Background Tsetse flies transmit trypanosomes that cause human and African animal trypanosomosis, a debilitating disease of humans (sleeping sickness) and livestock (nagana). An area-wide integrated pest management campaign against Glossina palpalis gambiensis has been implemented in Senegal since 2010 that includes a sterile insect technique (SIT) component. The SIT can only be successful when the sterile males that are destined for release have a flight ability, survival and competitiveness that are as close as possible to that of their wild male counterparts. Methodology/Principal Findings Tests were developed to assess the quality of G. p. gambiensis males that emerged from pupae that were produced and irradiated in Burkina Faso and Slovakia (irradiation done in Seibersdorf, Austria) and transported weekly under chilled conditions to Dakar, Senegal. For each consignment a sample of 50 pupae was used for a quality control test (QC group). To assess flight ability, the pupae were put in a cylinder filtering emerged flies that were able to escape the cylinder. The survival of these flyers was thereafter monitored under stress conditions (without feeding). Remaining pupae were emerged and released in the target area of the eradication programme (RF group). The following parameter values were obtained for the QC flies: average emergence rate more than 69%, median survival of 6 days, and average flight ability of more than 35%. The quality protocol was a good proxy of fly quality, explaining a large part of the variances of the examined parameters. Conclusions/Significance The quality protocol described here will allow the accurate monitoring of the quality of shipped sterile male tsetse used in operational eradication programmes in the framework of the Pan-African Tsetse and Trypanosomosis Eradication Campaign. PMID:26562521

  11. Evidence for a receiver bias underlying female preference for a male mating pheromone in sea lamprey.

    PubMed

    Buchinger, T J; Wang, H; Li, W; Johnson, N S

    2013-11-22

    Receiver bias models suggest that a male sexual signal became exaggerated to match a pre-existing sensory, perceptual or cognitive disposition of the female. Accordingly, these models predict that females of related taxa possessing the ancestral state of signalling evolved preference for the male trait in a non-sexual context. We postulated that female preference for the male-released bile alcohol mating pheromone, 3 keto petromyzonol sulfate (3kPZS), of the sea lamprey (Petromyzon marinus) evolved as a result of a receiver bias. In particular, we propose that migratory silver lamprey (Ichthyomyzon unicuspis), a basal member of the Petromyzontidae, evolved a preference for 3kPZS released by stream-resident larvae as a means of identifying productive habitat for offspring. Larval silver lamprey released 3kPZS at rates sufficient to be detected by migratory lampreys. Females responded to 3kPZS by exhibiting upstream movement behaviours relevant in a migratory context, but did not exhibit proximate behaviours important to mate search and spawning. Male silver lamprey did not release 3kPZS at rates sufficient to be detected by females in natural high-volume stream environments. We infer that female silver lamprey cue onto 3kPZS excreted by stream-resident larvae as a mechanism to locate habitat conducive to offspring survival and that males do not signal with 3kPZS. We suggest that this female preference for a male signal in a non-sexual context represents a bias leading to the sexual signalling observed in sea lamprey.

  12. Evidence for a receiver bias underlying female preference for a male mating pheromone in sea lamprey

    PubMed Central

    Buchinger, T. J.; Wang, H.; Li, W.; Johnson, N. S.

    2013-01-01

    Receiver bias models suggest that a male sexual signal became exaggerated to match a pre-existing sensory, perceptual or cognitive disposition of the female. Accordingly, these models predict that females of related taxa possessing the ancestral state of signalling evolved preference for the male trait in a non-sexual context. We postulated that female preference for the male-released bile alcohol mating pheromone, 3 keto petromyzonol sulfate (3kPZS), of the sea lamprey (Petromyzon marinus) evolved as a result of a receiver bias. In particular, we propose that migratory silver lamprey (Ichthyomyzon unicuspis), a basal member of the Petromyzontidae, evolved a preference for 3kPZS released by stream-resident larvae as a means of identifying productive habitat for offspring. Larval silver lamprey released 3kPZS at rates sufficient to be detected by migratory lampreys. Females responded to 3kPZS by exhibiting upstream movement behaviours relevant in a migratory context, but did not exhibit proximate behaviours important to mate search and spawning. Male silver lamprey did not release 3kPZS at rates sufficient to be detected by females in natural high-volume stream environments. We infer that female silver lamprey cue onto 3kPZS excreted by stream-resident larvae as a mechanism to locate habitat conducive to offspring survival and that males do not signal with 3kPZS. We suggest that this female preference for a male signal in a non-sexual context represents a bias leading to the sexual signalling observed in sea lamprey. PMID:24068361

  13. Evidence for a receiver bias underlying female preference for a male mating pheromone in sea lamprey

    USGS Publications Warehouse

    Buchinger, Tyler J.; Wang, Huiyong; Li, Weiming; Johnson, Nicholas S.

    2013-01-01

    Receiver bias models suggest that a male sexual signal became exaggerated to match a pre-existing sensory, perceptual or cognitive disposition of the female. Accordingly, these models predict that females of related taxa possessing the ancestral state of signalling evolved preference for the male trait in a non-sexual context. We postulated that female preference for the male-released bile alcohol mating pheromone, 3 keto petromyzonol sulfate (3kPZS), of the sea lamprey (Petromyzon marinus) evolved as a result of a receiver bias. In particular, we propose that migratory silver lamprey (Ichthyomyzon unicuspis), a basal member of the Petromyzontidae, evolved a preference for 3kPZS released by stream-resident larvae as a means of identifying productive habitat for offspring. Larval silver lamprey released 3kPZS at rates sufficient to be detected by migratory lampreys. Females responded to 3kPZS by exhibiting upstream movement behaviours relevant in a migratory context, but did not exhibit proximate behaviours important to mate search and spawning. Male silver lamprey did not release 3kPZS at rates sufficient to be detected by females in natural high-volume stream environments. We infer that female silver lamprey cue onto 3kPZS excreted by stream-resident larvae as a mechanism to locate habitat conducive to offspring survival and that males do not signal with 3kPZS. We suggest that this female preference for a male signal in a non-sexual context represents a bias leading to the sexual signalling observed in sea lamprey.

  14. A mutation in Thermosensitive Male Sterile 1, encoding a heat shock protein with DnaJ and PDI domains, leads to thermosensitive gametophytic male sterility in Arabidopsis.

    PubMed

    Yang, Ke-Zhen; Xia, Chuan; Liu, Xiao-Lei; Dou, Xiao-Ying; Wang, Wei; Chen, Li-Qun; Zhang, Xue-Qin; Xie, Li-Fen; He, Luyan; Ma, Xuan; Ye, De

    2009-03-01

    In most flowering plant species, pollination and fertilization occur during the hot summer, so plants must have evolved a mechanism that ensures normal growth of their pollen tubes at high temperatures. Despite its importance to plant reproduction, little is known about the molecular basis of thermotolerance in pollen tubes. Here we report the identification and characterization of a novel Arabidopsis gene, Thermosensitive Male Sterile 1 (TMS1), which plays an important role in thermotolerance of pollen tubes. TMS1 encodes a Hsp40-homologous protein with a DnaJ domain and an a_ERdj5_C domain found in protein disulfide isomerases (PDI). Purified TMS1 expressed in Escherichia coli (BL21 DE3) had the reductive activity of PDI. TMS1 was expressed in pollen grains, pollen tubes and other vegetative tissues, including leaves, stems and roots. Heat shock treatment at 37 degrees C increased its expression levels in growing pollen tubes as well as in vegetative tissues. A knockout mutation in TMS1 grown at 30 degrees C had greatly retarded pollen tube growth in the transmitting tract, resulting in a significant reduction in male fertility. Our study suggests that TMS1 is required for thermotolerance of pollen tubes in Arabidopsis, possibly by functioning as a co-molecular chaperone.

  15. Eavesdropping to Find Mates: The Function of Male Hearing for a Cicada-Hunting Parasitoid Fly, Emblemasoma erro (Diptera: Sarcophagidae).

    PubMed

    Stucky, Brian J

    2016-01-01

    Females of several species of dipteran parasitoids use long-range hearing to locate hosts for their offspring by eavesdropping on the acoustic mating calls of other insects. Males of these acoustic eavesdropping parasitoids also have physiologically functional ears, but so far, no adaptive function for male hearing has been discovered. I investigated the function of male hearing for the sarcophagid fly Emblemasoma erro Aldrich, an acoustic parasitoid of cicadas, by testing the hypothesis that both male and female E. erro use hearing to locate potential mates. I found that both male and nongravid female E. erro perform phonotaxis to the sounds of calling cicadas, that male flies engage in short-range, mate-finding behavior once they arrive at a sound source, and that encounters between females and males at a sound source can lead to copulation. Thus, cicada calling songs appear to serve as a mate-finding cue for both sexes of E. erro Emblemasoma erro's mate-finding behavior is compared to that of other sarcophagid flies, other acoustic parasitoids, and nonacoustic eavesdropping parasitoids.

  16. Eavesdropping to Find Mates: The Function of Male Hearing for a Cicada-Hunting Parasitoid Fly, Emblemasoma erro (Diptera: Sarcophagidae)

    PubMed Central

    Stucky, Brian J.

    2016-01-01

    Females of several species of dipteran parasitoids use long-range hearing to locate hosts for their offspring by eavesdropping on the acoustic mating calls of other insects. Males of these acoustic eavesdropping parasitoids also have physiologically functional ears, but so far, no adaptive function for male hearing has been discovered. I investigated the function of male hearing for the sarcophagid fly Emblemasoma erro Aldrich, an acoustic parasitoid of cicadas, by testing the hypothesis that both male and female E. erro use hearing to locate potential mates. I found that both male and nongravid female E. erro perform phonotaxis to the sounds of calling cicadas, that male flies engage in short-range, mate-finding behavior once they arrive at a sound source, and that encounters between females and males at a sound source can lead to copulation. Thus, cicada calling songs appear to serve as a mate-finding cue for both sexes of E. erro. Emblemasoma erro’s mate-finding behavior is compared to that of other sarcophagid flies, other acoustic parasitoids, and nonacoustic eavesdropping parasitoids. PMID:27382133

  17. Differential allocation in a lekking bird: females lay larger eggs and are more likely to have male chicks when they mate with less related males

    PubMed Central

    Sardell, Rebecca J.; DuVal, Emily H.

    2014-01-01

    The differential allocation hypothesis predicts increased investment in offspring when females mate with high-quality males. Few studies have tested whether investment varies with mate relatedness, despite evidence that non-additive gene action influences mate and offspring genetic quality. We tested whether female lekking lance-tailed manakins (Chiroxiphia lanceolata) adjust offspring sex and egg volume in response to mate attractiveness (annual reproductive success, ARS), heterozygosity and relatedness. Across 968 offspring, the probability of being male decreased with increasing parental relatedness but not father ARS or heterozygosity. This correlation tended to diminish with increasing lay-date. Across 162 offspring, egg volume correlated negatively with parental relatedness and varied with lay-date, but was unrelated to father ARS or heterozygosity. Offspring sex and egg size were unrelated to maternal age. Comparisons of maternal half-siblings in broods with no mortality produced similar results, indicating differential allocation rather than covariation between female quality and relatedness or sex-specific inbreeding depression in survival. As males suffer greater inbreeding depression, overproducing females after mating with related males may reduce fitness costs of inbreeding in a system with no inbreeding avoidance, while biasing the sex of outbred offspring towards males may maximize fitness via increased mating success of outbred sons. PMID:24225457

  18. Effects of Nuclear Genomes on Anther Development in Cytoplasmic Male Sterile Chicories (Cichorium intybus L.): Morphological Analysis

    PubMed Central

    Habarugira, Ildephonse; Hendriks, Theo; Quillet, Marie-Christine; Hilbert, Jean-Louis; Rambaud, Caroline

    2015-01-01

    The Cichorium intybus flower development in fertile, cytoplasmic male sterility (CMS 524) and various phenotypes carrying the 524 male sterile cytoplasm was investigated macroscopically and by light microscopy. The development was similar in fertile and in male sterile florets up to meiosis, and then it was affected in anther wall structure and pollen grain development in male sterile floret. In the male sterile plants, the tapetum intrusion after meiosis was less remarkable, the microspores started to abort at vacuolate stage, the connective tissue collapsed, and endothecium failed to expand normally and did not undergo cell wall lignification, which prevented anther opening since the septum and stomium were not disrupted. Crosses undertaken in order to introduce the CMS 524 into two different nuclear backgrounds gave rise to morphologically diversified progenies due to different nuclear-mitochondrial interactions. Macroscopic and cytological investigations showed that pollen-donor plants belonging to Jupiter population had potential capacity to restore fertility while the CC line could be considered as a sterility maintainer. PMID:25861678

  19. Better mate in the shade: enhancement of male mating behaviour in the cabbage butterfly, Pieris rapae crucivora, in a UV-rich environment.

    PubMed

    Obara, Yoshiaki; Koshitaka, Hisaharu; Arikawa, Kentaro

    2008-12-01

    Ultraviolet (UV) vision is widespread in a variety of animals, playing important roles in behaviours such as foraging and reproduction. Despite accumulated information about UV vision and UV-dependent behaviours of animals, little is known about the effect of temporal changes and local variations in UV light on UV-dependent behaviour. Here we report the mating behaviour of male cabbage butterfly, Pieris rapae crucivora, in environments with varying content of UV light. We first confirmed that the relative UV content is higher in shaded places than in sunny places. We furthermore arranged experimental areas with varying UV contents in the field, where we compared three aspects of male mating behaviour: visual localization of females, female-searching flight and copulation success rate. In all aspects males performed more actively in UV-rich environments: males searched females for longer, approached females preferentially in the shade and copulated there more frequently. Apparently, female-searching males detect females more easily in a UV-rich environment. The present findings should be taken into consideration when UV-dependent behaviours, visual mate choice in particular, are studied.

  20. A novel male sterility-fertility restoration system in plants for hybrid seed production

    PubMed Central

    Singh, Surendra Pratap; Singh, Sudhir P.; Pandey, Tripti; Singh, Ram Rakshpal; Sawant, Samir V.

    2015-01-01

    Hybrid seeds are used for stimulated crop production, as they harness heterosis. The achievement of complete male-sterility in the female-parent and the restored-fertility in F1-hybrids are the major bottlenecks in the commercial hybrid seed production. Here, we report a male sterility–fertility restoration system by engineering the inmost nutritive anther wall layer tapetum of female and male parents. In the female parent, high–level, and stringent expression of Arabidopsis autophagy–related gene BECLIN1 was achieved in the tapetum, which altered the tapetal degeneration program, leading to male sterility. This works on our previously demonstrated expression cassette based on functional complementation of TATA-box mutant (TGTA) promoter and TATA-binding protein mutant3 (TBPm3), with modification by conjugating Long Hypocotyle in Far-Red1 fragment (HFR1NT131) with TBPm3 (HFR1NT131-TBPm3) to exercise regulatory control over it. In the male parent, tapetum–specific Constitutive photo-morphogenesis1 (COP1) was expressed. The F1 obtained by crossing these engineered parents showed decreased BECLIN1 expression, which was further completely abolished when COP1-mutant (COP1L105A) was used as a male parent, leading to normal tapetal development and restored fertility. The system works on COP1-HFR1 interaction and COP1–mediated degradation of TBPm3 pool (HFR1NT131-TBPm3). The system can be deployed for hybrid seed production in agricultural crops. PMID:26073981

  1. The sterile-male-release technique in Great Lakes sea lamprey management

    USGS Publications Warehouse

    Bergstedt, Roger A.; Twohey, Michael B.

    2005-01-01

    The parasitic sea lamprey (Petromyzon marinus) has been a serious pest since its introduction into the Great Lakes, where it contributed to severe imbalances in the fish communities by selectively removing large predators (Smith 1968; Christie 1974; Schneider et al.1996). Since the 1950s, restoration and maintenance of predator-prey balance has depended on the Great Lakes Fishery Commission (GLFC) sea lamprey management program. Initially, management relied primarily on stream treatments with a selective lampricide to kill larvae, on barriers to migration, and on trapping to remove potential spawners (Smith and Tibbles 1980). By the late 1970s, however, it was clear that the future of sea lamprey management lay in development of a larger array of control strategies, including more alternatives to lampricide applications (Sawyer 1980). Since then the only new alternative to chemical control to reach operational status is the release of sterilized male sea lampreys. Research on the concept began at the USGS, Hammond Bay Biological Station in Millersburg, MI (HBBS) during the 1970s (Hanson and Manion 1980). Development and evaluation continued through the 1980s, leading to the release of sterilized males in Great Lakes tributaries since 1991 (Twohey et al. 2003a). The objectives of this paper are 1) to review the implementation and evaluations of sterile-male-release technique (SMRT) as it is being applied against sea lampreys in the Great Lakes, 2) to review our current understanding of its efficacy, and 3) to identify additional research areas and topics that would increase either the efficacy of SMRT or expand its geographic potential for application.

  2. Tomato Male sterile 1035 is essential for pollen development and meiosis in anthers.

    PubMed

    Jeong, Hee-Jin; Kang, Jin-Ho; Zhao, Meiai; Kwon, Jin-Kyung; Choi, Hak-Soon; Bae, Jung Hwan; Lee, Hyun-Ah; Joung, Young-Hee; Choi, Doil; Kang, Byoung-Cheorl

    2014-12-01

    Male fertility in flowering plants depends on proper cellular differentiation in anthers. Meiosis and tapetum development are particularly important processes in pollen production. In this study, we showed that the tomato male sterile (ms10(35)) mutant of cultivated tomato (Solanum lycopersicum) exhibited dysfunctional meiosis and an abnormal tapetum during anther development, resulting in no pollen production. We demonstrated that Ms10(35) encodes a basic helix-loop-helix transcription factor that is specifically expressed in meiocyte and tapetal tissue from pre-meiotic to tetrad stages. Transgenic expression of the Ms10(35) gene from its native promoter complemented the male sterility of the ms10(35) mutant. In addition, RNA-sequencing-based transcriptome analysis revealed that Ms10(35) regulates 246 genes involved in anther development processes such as meiosis, tapetum development, cell-wall degradation, pollen wall formation, transport, and lipid metabolism. Our results indicate that Ms10(35) plays key roles in regulating both meiosis and programmed cell death of the tapetum during microsporogenesis.

  3. Why small males have big sperm: dimorphic squid sperm linked to alternative mating behaviours

    PubMed Central

    2011-01-01

    Background Sperm cells are the target of strong sexual selection that may drive changes in sperm structure and function to maximize fertilisation success. Sperm evolution is regarded to be one of the major consequences of sperm competition in polyandrous species, however it can also be driven by adaptation to the environmental conditions at the site of fertilization. Strong stabilizing selection limits intra-specific variation, and therefore polymorphism, among fertile sperm (eusperm). Here we analyzed reproductive morphology differences among males employing characteristic alternative mating behaviours, and so potentially different conditions of sperm competition and fertilization environment, in the squid Loligo bleekeri. Results Large consort males transfer smaller (average total length = 73 μm) sperm to a female's internal sperm storage location, inside the oviduct; whereas small sneaker males transfer larger (99 μm) sperm to an external location around the seminal receptacle near the mouth. No significant difference in swimming speed was observed between consort and sneaker sperm. Furthermore, sperm precedence in the seminal receptacle was not biased toward longer sperm, suggesting no evidence for large sperm being favoured in competition for space in the sperm storage organ among sneaker males. Conclusions Here we report the first case, in the squid Loligo bleekeri, where distinctly dimorphic eusperm are produced by different sized males that employ alternative mating behaviours. Our results found no evidence that the distinct sperm dimorphism was driven by between- and within-tactic sperm competition. We propose that presence of alternative fertilization environments with distinct characteristics (i.e. internal or external), whether or not in combination with the effects of sperm competition, can drive the disruptive evolution of sperm size. PMID:21831296

  4. Effects of egg testosterone on female mate choice and male sexual behavior in the pheasant.

    PubMed

    Bonisoli-Alquati, Andrea; Matteo, Angelo; Ambrosini, Roberto; Rubolini, Diego; Romano, Maria; Caprioli, Manuela; Dessì-Fulgheri, Francesco; Baratti, Mariella; Saino, Nicola

    2011-01-01

    Evidence is accumulating that sex steroids in the eggs, besides affecting progeny phenotype and behavior in the short term, also have enduring effects until adulthood, when they may translate into differences in reproductive strategies and success. Maternal steroids transfer may therefore affect both agonistic behavior and mate choice decisions, either through the promotion of body size and condition or through a priming effect on the neuroendocrine system. However, owing to the prevalence of a short-term perspective, relevance of maternal transfer of sex steroids to sexual selection processes has been seldom studied. Here we investigate the effects of an experimental increase in egg testosterone on male dominance and copulation success in the ring-necked pheasant, Phasianus colchicus, a polygynous galliform with multiple male ornamental traits, in captivity. We found that females from testosterone (T) injected eggs copulated less than control females. Males from T-injected eggs obtained more copulations than control males, specifically with control females. The effect of male 'ordinary' and secondary sexual traits on either dominance or copulation frequency did not depend on early exposure to T, nor did T treatment affect male dominance. Present results demonstrate that variation in the early hormonal environment set up by mothers affects sexual behavior of the offspring, which might translate into fitness differences.

  5. Co-Evolution of the Mating Position and Male Genitalia in Insects: A Case Study of a Hangingfly

    PubMed Central

    Gao, Qionghua; Hua, Baozhen

    2013-01-01

    Hangingflies are unique for the male providing a nuptial gift to the female during mating and taking a face-to-face hanging copulation with the female. Their male genitalia are peculiar for an extremely elongated penisfilum, a pair of well-developed epandrial lobes (9th tergum), and a pair of degenerated gonostyli. However, the co-evolution of their face-to-face copulation behavior and the male genitalia has rarely been studied hitherto. In this paper the mating behavior of the hangingfly Bittacus planus Cheng, 1949 was observed under laboratory conditions, and the morphology of the male and female external genitalia was investigated using light and scanning electron microscopy. The male provides an insect prey as a nuptial gift to the female in courtship and mating process, and commits a face-to-face copulation. During copulation, the male abdomen twists temporarily about 180° to accommodate their face-to-face mating position. The aedeagal complex has an extremely elongated penisfilum, corresponding to the elongated spermathecal duct of the female. The well-developed epandrial lobes serve as claspers to grasp the female subgenital plate during copulation, replacing the function of gonostyli, which are greatly reduced in Bittacidae. The modified proctiger assists the penisfilum to stretch and to enter into the female spermathecal duct. The possible reasons why this species might mate face-to-face are briefly discussed. PMID:24312490

  6. Mating Behavior, Male Sensory Cilia, and Polycystins in C. elegans” Chapter

    PubMed Central

    Barr, Maureen M.

    2015-01-01

    The investigation of C. elegans males and the male-specific sensory neurons required for mating behaviors has provided insight into the molecular function of polycystins and mechanisms that are needed for polycystin ciliary localization. In humans, polycystin 1 and polycystin 2 are needed for kidney function; loss of polycystin function leads to autosomal dominant polycystic kidney disease (ADPKD). Polycystins localize to cilia in C. elegans and mammals, a finding that has guided research into ADPKD. The discovery that the polycystins form ciliary receptors in male-specific neurons needed for mating behaviors has also helped to unlock insights into two additional exciting new areas: the secretion of extracellular vesicles; and mechanisms of ciliary specialization. First, we will summarize the studies done in C. elegans regarding the expression, localization, and function of the polycystin 1 and 2 homologs, LOV-1 and PKD-2, and discuss insights gained from this basic research. Molecules that are co-expressed with the polycystins in the male-specific neurons may identify evolutionarily conserved molecular mechanisms for polycystin function and localization. We will discuss the finding that polycystins are secreted in extracellular vesicles that evoke behavioral change in males, suggesting that such vesicles provide a novel form of communication to conspecifics in the environment. In humans, polycystin-containing extracellular vesicles are secreted in urine and can be taken up by cilia, and quickly internalized. Therefore, communication by polycystin-containing extracellular vesicles may also use mechanisms that are evolutionarily conserved from nematode to human. Lastly, different cilia display structural and functional differences that specialize them for particular tasks, despite the fact that virtually all cilia are built by a conserved Intraflagellar Transport (IFT) mechanism and share some basic structural features. Comparative analysis of the male

  7. Nutritional correlates and mate acquisition role of multiple sexual traits in male collared flycatchers

    NASA Astrophysics Data System (ADS)

    Hegyi, Gergely; Szöllősi, Eszter; Jenni-Eiermann, Susanne; Török, János; Eens, Marcel; Garamszegi, László Zsolt

    2010-06-01

    The information content of a sexual signal may predict its importance in a multiple signal system. Many studies have correlated sexual signal expression with the absolute levels of nutrient reserves. In contrast, the changes of nutrient reserves associated with signal expression are largely unknown in the wild due to technical limitations although they are important determinants of signal information content. We compared two visual and eight acoustic sexual traits in male collared flycatchers to see whether the nutritional correlates of expression predict the role of the signal in sexual selection. We used single point assays of plasma lipid metabolites to estimate short-term changes in nutritional state in relation to sexual trait expression during courtship. As a measure of sexual selection, we estimated the relationship with pairing latency after arrival in a 4-year dataset. Males which found a mate rapidly were characterized by large wing and forehead patches, but small song strophe complexity and small figure repertoire size. Traits more strongly related to pairing latency were also more closely related to changes in nutrient reserves. This indicates a link between signal role and information content. Small wing patches and, surprisingly, complex songs seemed to indicate poor phenotypic quality and were apparently disfavoured at mate acquisition in our population. Future studies of the information content of sexual traits, especially dynamic traits such as song, may benefit from the use of plasma metabolite profiles as non-invasive indicators of short-term changes in body condition.

  8. A recessive gene controlling male sterility sensitive to short daylength/low temperature in wheat (Triticum aestivum L.).

    PubMed

    Chen, Xiao-dong; Sun, Dong-fa; Rong, De-fu; Peng, Jun-hua; Li, Cheng-dao

    2011-11-01

    Utilization of a two-line breeding system via photoperiod-thermo sensitive male sterility has a great potential for hybrid production in wheat (Triticum aestivum L.). 337S is a novel wheat male sterile line sensitive to both short daylength/low temperature and long daylength/high temperature. Five F(2) populations derived from the crosses between 337S and five common wheat varieties were developed for genetic analysis. All F(1)'s were highly fertile while segregation occurred in the F(2) populations with a ratio of 3 fertile:1 sterile under short daylength/low temperature. It is shown that male sterility in 337S was controlled by a single recessive gene, temporarily designated as wptms3. Bulked segregant analysis (BSA) coupled with simple sequence repeat (SSR) markers was applied to map the sterile gene using one mapping population. The wptms3 gene was mapped to chromosome arm 1BS and flanked by Xgwm413 and Xgwm182 at a genetic distance of 3.2 and 23.5 cM, respectively. The accuracy and efficiency of marker-assisted selection were evaluated and proved essential for identifying homozygous recessive male sterile genotypes of the wptms3 gene in F(2) generation.

  9. Flying the nest: male dispersal and multiple paternity enables extrafamilial matings for the invasive bark beetle Dendroctonus micans.

    PubMed

    Fraser, C I; Brahy, O; Mardulyn, P; Dohet, L; Mayer, F; Grégoire, J-C

    2014-10-01

    There is an evolutionary trade-off between the resources that a species invests in dispersal versus those invested in reproduction. For many insects, reproductive success in patchily-distributed species can be improved by sibling-mating. In many cases, such strategies correspond to sexual dimorphism, with males-whose reproductive activities can take place without dispersal-investing less energy in development of dispersive resources such as large body size and wings. This dimorphism is particularly likely when males have little or no chance of mating outside their place of birth, such as when sperm competition precludes successful fertilisation in females that have already mated. The economically important bark beetle pest species Dendroctonus micans (Coleoptera: Curculionidae, Scolytinae) has been considered to be exclusively sibling-mating, with 90% of females having already mated with their brothers by emergence. The species does not, however, show strong sexual dimorphism; males closely resemble females, and have been observed flying through forests. We hypothesised that this lack of sexual dimorphism indicates that male D. micans are able to mate with unrelated females, and to sire some or all of their offspring, permitting extrafamilial reproduction. Using novel microsatellite markers, we carried out cross-breeding laboratory experiments and conducted paternity analyses of resulting offspring. Our results demonstrate that a second mating with a less-related male can indeed lead to some offspring being sired by the latecomer, but that most are sired by the first, sibling male. We discuss these findings in the context of sperm competition versus possible outbreeding depression.

  10. Interspecific aggression, not interspecific mating, drives character displacement in the wing coloration of male rubyspot damselflies (Hetaerina)

    PubMed Central

    Drury, J. P.; Grether, G. F.

    2014-01-01

    Traits that mediate intraspecific social interactions may overlap in closely related sympatric species, resulting in costly between-species interactions. Such interactions have principally interested investigators studying the evolution of reproductive isolation via reproductive character displacement (RCD) or reinforcement, yet in addition to reproductive interference, interspecific trait overlap can lead to costly between-species aggression. Previous research on rubyspot damselflies (Hetaerina spp.) demonstrated that sympatric shifts in male wing colour patterns and competitor recognition reduce interspecific aggression, supporting the hypothesis that agonistic character displacement (ACD) drove trait shifts. However, a recent theoretical model shows that RCD overshadows ACD if the same male trait is used for both female mate recognition and male competitor recognition. To determine whether female mate recognition is based on male wing coloration in Hetaerina, we conducted a phenotype manipulation experiment. Compared to control males, male H. americana with wings manipulated to resemble a sympatric congener (H. titia) suffered no reduction in mating success. Thus, female mate recognition is not based on species differences in male wing coloration. Experimental males did, however, experience higher interspecific fighting rates and reduced survival compared to controls. These results greatly strengthen the case for ACD and highlight the mechanistic distinction between ACD and RCD. PMID:25339724

  11. Safe sex: male-female coalitions and pre-copulatory mate-guarding in a fiddler crab.

    PubMed

    Milner, Richard N C; Jennions, Michael D; Backwell, Patricia R Y

    2010-04-23

    In fiddler crabs both males and females defend territories that are essential for survival. Given pronounced sexual dimorphism in weaponry, how do weaponless females defend their territory from well-armed males? Using observational data and two simple experiments, we test whether male Uca annulipes protect their female neighbours from conspecific intruders. We show that males defend their female neighbours against male but not female intruders. We also show that females sometimes mate with their immediate neighbours. Male defence of female neighbours appears to represent both pre-copulatory mate-guarding and a territorial coalition. Males who ensure that their neighbour remains female could benefit through increased opportunity for future reproductive success and lower boundary maintenance costs.

  12. Genetic studies on cytoplasmic male sterility in maize. Progress report, April 15, 1990--April 14, 1992

    SciTech Connect

    Laughnan, J.R.

    1992-05-01

    Our research concerns the basic mechanisms of cytoplasmic male sterility (CMS) and fertility restoration in maize. The molecular determination of CMS is in the DNA of the mitochondria (mtDNA) but specific nuclear restorer-of-fertility (Rf) genes can overrule the male-sterile effect of the cytoplasm. Our approach to the study of the Rf genes is threefold. We are attempting to tag the cms-S Rf genes and the cms-T Rf2 gene with controlling elements (CEs). Since we have identified a number of spontaneous Rf genes for cms-S and have demonstrated that they are themselves transposable, we are also searching for cases in which an Rf gene is inserted into a wild-type gene. The other aspect of our research involves the nuclear control over the organization of the mitochondrial genome. We found that the changes in mtDNA organization upon cytoplasmic reversion to fertility were characteristic of the nuclear background in which the reversion event occurred. We have investigated whether these differences are a reflection of differences in the organization of the mtDNA genome before reversion.

  13. Somatic hybrids between Arabidopsis thaliana and cytoplasmic male-sterile radish (Raphanus sativus).

    PubMed

    Yamagishi, H; Glimelius, K

    2003-08-01

    Somatic hybrids were produced by protoplast fusion between Arabidopsis thaliana ecotype Columbia and a male-sterile radish line MS-Gensuke ( Raphanus sativus) with the Ogura cytoplasm. Forty-one shoots were differentiated from the regenerated calli and established as shoot cultures in vitro. About 20 of these shoots were judged to be hybrids based on growth characteristics and morphology. Molecular analyses of 11 shoots were performed, confirming the hybrid features. Of these 11 shoots, eight were established as rooted plants in the greenhouse. Polymerase chain reaction and randomly amplified polymorphic DNA analyses of the nuclear genomes of all analyzed shoots and plants confirmed that they contained hybrid DNA patterns. Their chromosome numbers also supported the hybrid nature of the plants. Investigations of the organelles in the hybrids revealed that the chloroplast (cp) genome was exclusively represented by radish cpDNA, while the mitochondrial DNA configuration showed a combination of both parental genomes as well as fragments unique to the hybrids. Hybrid plants that flowered were male-sterile independent of the presence of the Ogura CMS-gene orf138.

  14. 11-Ketotestosterone inhibits the alternative mating tactic in sneaker males of the peacock blenny, Salaria pavo.

    PubMed

    Oliveira, R F; Carneiro, L A; Gonçalves, D M; Canario, A V; Grober, M S

    2001-01-01

    In the peacock blenny, Salaria pavo, a species with courtship sex-role reversal, smaller, younger males mimic the courtship behavior and the nuptial coloration of females in order to get access to nests during spawning and to parasitize egg fertilization from nest-holder males. Later in their life, sneakers transform both morphologically and behaviorally into nest-holder males. In the present paper we investigate the activational role of 11-ketotestosterone (KT), the most potent androgen in most teleost species, to promote the switch between tactics in sneaker males of S. pavo. Sneakers were implanted either with KT or with control (i.e. castor oil) silastic implants. A week after implantation they were subjected to a set of behavioral tests and morphometric measurements. KT treatment promoted the differentiation of secondary sex characters, such as the anal glands, and inhibited the expression of female courtship behavior. KT-treated sneakers also showed a trend toward less frequent display of female nuptial coloration. There was no effect of KT treatment on the expression of typical nest-holder male behavior. Finally, there was no effect of KT treatment on the number or soma size of arginine vasotocin neurons in the preoptic area, which are often associated with the expression of vertebrate sexual behavior. Thus, KT seems to play a key role in mating tactic switching by inhibiting the expression of female courtship behavior and by promoting the development of male displaying traits (e.g. anal glands). The lack of a KT effect on behavior typical of nest-holding males and vasotocinergic preoptic neurons suggests that a longer time frame or other endocrine/social signals are needed for the initiation of these traits in males that are switching tactics.

  15. Mate choice for a male carotenoid-based ornament is linked to female dietary carotenoid intake and accumulation

    PubMed Central

    2012-01-01

    Background The coevolution of male traits and female mate preferences has led to the elaboration and diversification of sexually selected traits; however the mechanisms that mediate trait-preference coevolution are largely unknown. Carotenoid acquisition and accumulation are key determinants of the expression of male sexually selected carotenoid-based coloration and a primary mechanism maintaining the honest information content of these signals. Carotenoids also influence female health and reproduction in ways that may alter the costs and benefits of mate choice behaviours and thus provide a potential biochemical link between the expression of male traits and female preferences. To test this hypothesis, we manipulated the dietary carotenoid levels of captive female house finches (Carpodacus mexicanus) and assessed their mate choice behavior in response to color-manipulated male finches. Results Females preferred to associate with red males, but carotenoid supplementation did not influence the direction or strength of this preference. Females receiving a low-carotenoid diet were less responsive to males in general, and discrimination among the colorful males was positively linked to female plasma carotenoid levels at the beginning of the study when the diet of all birds was carotenoid-limited. Conclusions Although female preference for red males was not influenced by carotenoid intake, changes in mating responsiveness and discrimination linked to female carotenoid status may alter how this preference is translated into choice. The reddest males, with the most carotenoid rich plumage, tend to pair early in the breeding season. If carotenoid-related variations in female choice behaviour shift the timing of pairing, then they have the potential to promote assortative mating by carotenoid status and drive the evolution of carotenoid-based male plumage coloration. PMID:22233462

  16. Flying the nest: male dispersal and multiple paternity enables extrafamilial matings for the invasive bark beetle Dendroctonus micans

    PubMed Central

    Fraser, C I; Brahy, O; Mardulyn, P; Dohet, L; Mayer, F; Grégoire, J-C

    2014-01-01

    There is an evolutionary trade-off between the resources that a species invests in dispersal versus those invested in reproduction. For many insects, reproductive success in patchily-distributed species can be improved by sibling-mating. In many cases, such strategies correspond to sexual dimorphism, with males–whose reproductive activities can take place without dispersal–investing less energy in development of dispersive resources such as large body size and wings. This dimorphism is particularly likely when males have little or no chance of mating outside their place of birth, such as when sperm competition precludes successful fertilisation in females that have already mated. The economically important bark beetle pest species Dendroctonus micans (Coleoptera: Curculionidae, Scolytinae) has been considered to be exclusively sibling-mating, with 90% of females having already mated with their brothers by emergence. The species does not, however, show strong sexual dimorphism; males closely resemble females, and have been observed flying through forests. We hypothesised that this lack of sexual dimorphism indicates that male D. micans are able to mate with unrelated females, and to sire some or all of their offspring, permitting extrafamilial reproduction. Using novel microsatellite markers, we carried out cross-breeding laboratory experiments and conducted paternity analyses of resulting offspring. Our results demonstrate that a second mating with a less-related male can indeed lead to some offspring being sired by the latecomer, but that most are sired by the first, sibling male. We discuss these findings in the context of sperm competition versus possible outbreeding depression. PMID:24736784

  17. Mutation in CSA creates a new photoperiod-sensitive genic male sterile line applicable for hybrid rice seed production.

    PubMed

    Zhang, Hui; Xu, Chenxi; He, Yi; Zong, Jie; Yang, Xijia; Si, Huamin; Sun, Zongxiu; Hu, Jianping; Liang, Wanqi; Zhang, Dabing

    2013-01-02

    Rice is a major staple food worldwide. Making hybrid rice has proved to be an effective strategy to significantly increase grain yield. Current hybrid rice technologies rely on male sterile lines and have been used predominantly in indica cultivars. However, intrinsic problems exist in the implementation of these technologies, such as limited germplasms and unpredictable conversions from sterility to fertility in the field. Here, we describe a photoperiod-controlled male sterile line, carbon starved anther (csa), which contains a mutation in an R2R3 MYB transcription regulator of pollen development. This mutation was introduced into indica and japonica rice, and it rendered male sterility under short-day conditions and male fertility under long-day conditions in both lines. Furthermore, F(1) plants of csa and a restorer line JP69 exhibited heterosis (hybrid vigor), suggesting the feasibility of using this mutation to create hybrid rice. The csa-based photoperiod-sensitive male sterile line allows the establishment of a stable two-line hybrid system, which promises to have a significant impact on agriculture.

  18. Expression of a pathogen-induced cysteine protease (AdCP) in tapetum results in male sterility in transgenic tobacco.

    PubMed

    Shukla, Pawan; Singh, Naveen Kumar; Kumar, Dilip; Vijayan, Sambasivam; Ahmed, Israr; Kirti, Pulugurtha Bharadwaja

    2014-06-01

    Usable male sterility systems have immense potential in developing hybrid varieties in crop plants, which can also be used as a biological safety containment to prevent horizontal transgene flow. Barnase-Barstar system developed earlier was the first approach to engineer male sterility in plants. In an analogous situation, we have evolved a system of inducing pollen abortion and male sterility in transgenic tobacco by expressing a plant gene coding for a protein with known developmental function in contrast to the Barnase-Barstar system, which deploys genes of prokaryotic origin, i.e., from Bacillus amyloliquefaciens. We have used a plant pathogen-induced gene, cysteine protease for inducing male sterility. This gene was identified in the wild peanut, Arachis diogoi differentially expressed when it was challenged with the late leaf spot pathogen, Phaeoisariopsis personata. Arachis diogoi cysteine protease (AdCP) was expressed under the strong tapetum-specific promoter (TA29) and tobacco transformants were generated. Morphological and histological analysis of AdCP transgenic plants showed ablated tapetum and complete pollen abortion in three transgenic lines. Furthermore, transcript analysis displayed the expression of cysteine protease in these male sterile lines and the expression of the protein was identified in western blot analysis using its polyclonal antibody raised in the rabbit system.

  19. Sequencing and annotation of the chloroplast DNAs and identification of polymorphisms distinguishing normal male-fertile and male-sterile cytoplasms of onion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due the biennial generation time of onion, classical crossing takes at least four years to classify cytoplasms as normal (N) male-fertile or male-sterile (S). Molecular markers in the organellar DNAs that distinguish N and S cytoplasms are useful to reduce the time required to classify onion cytopla...

  20. Biochemical and molecular dissection of thermo-sensitive genetic male sterility in diploid cotton (Gossypium arboreum L).

    PubMed

    Sekhar, L; Khadi, B M; Patil, Rajesh S; Katageri, I S; Mukri, Ganapati

    2016-07-01

    Diploid cotton, due to its inherent problem of stamen brittleness, its found unsuitable for traditional method of hybrid seed production which involves hand emasculation followed by pollination. Due to shortfall in other methods viz., Genetic Male Sterility (GMS), as well as, Cytoplasmic Genetic Male Sterility (CGMS), hybrid seed production in diploid cotton becomes costly and thereby, covers less area among the total cotton grown area. Thermo-sensitive genetic male sterility, which overcomes the drawbacks of both GMS and CGMS can be an effective tool in coming years for hybrid cotton research. Understanding fertility and sterility variations, their relation with biochemical changes in plant is important before its application in plant breeding. Hence, the available TGMS line, Ga TGMS-3 obtained at Cotton Research Centre, UAS, Dharwad was studied for callase activity and markers associated with TGMS. The line Ga TGMS-3 had fertile anthers and showed less callase enzyme activity at pre-meiosis stage, high enzyme activity at tetrad releasing microspore stage and no callase activity during other stages. The counterpart TGMS sterile anthers displayed little higher callase activity at pre-meiosis stage, high activity at tetrad stage, but poor activity at tetrad releasing microspore stage. During tetrad stage, TGMS sterile anthers showed high callase enzyme activity giving every chance for early release of poorly developed microspores as compared to fertile anthers. At tetrad releasing microspores stage during which fertile anthers had strong callase enzyme activity led to microspores being released normally and developed normal pollen grains as compared to sterile anthers. The present investigation revealed that NAU2176, NAU2096 and BNL1227 primers can be used as tightly linked markers for TGMS trait, as evident from their differential expression in fertile and sterile anthers.

  1. A mitochondrial DNA sequence is associated with abnormal pollen development in cytoplasmic male sterile bean plants.

    PubMed Central

    Johns, C; Lu, M; Lyznik, A; Mackenzie, S

    1992-01-01

    Cytoplasmic male sterility (CMS) in common bean is associated with the presence of a 3-kb unique mitochondrial sequence designated pvs. The pvs sequence encodes at least two open reading frames (297 and 720 bp in length) with portions derived from the chloroplast genome. Fertility restoration by the nuclear restorer gene Fr results in the loss of this transcriptionally active unique region. We examined the effect of CMS (pvs present) and fertility restoration by Fr (pvs absent) on the pattern of pollen development in bean. In the CMS line, pollen aborted in the tetrad stage late in microgametogenesis. Microspores maintained cytoplasmic connections throughout pollen development, indicating aberrant or incomplete cytokinesis. Pollen-specific events associated with pollen abortion and fertility restoration imply that a gametophytic factor or event may be involved in CMS. In situ hybridization experiments suggested that significant reduction or complete loss of the mitochondrial sterility-associated sequence occurred in fertile pollen of F2 populations segregating for fertility. These observations support a model of fertility restoration by the loss of a mitochondrial DNA sequence prior to or during microsporogenesis/gametogenesis. PMID:1498602

  2. A cytoplasmic male sterility-associated mitochondrial peptide in common bean is post-translationally regulated.

    PubMed Central

    Sarria, R; Lyznik, A; Vallejos, C E; Mackenzie, S A

    1998-01-01

    Cytoplasmic male sterility in the common bean plant is associated with a dominant mitochondrial mutation designated pvs-or f 239 (for Phaseolus vulgaris sterility sequence open reading frame 239). The sequence is transcribed in both vegetative and reproductive tissues, but the translation product, ORF239, is present only in reproductive tissues. We present evidence to support a model of post-translational regulation of ORF239 expression based on the following observations. In organello translation experiments using purified mitochondria from young seedlings demonstrated accumulation of ORF239 only when a protease inhibitor was included. Proteolytic activity against ORF239 was observed in mitochondrial extracts fractionating with the mitochondrial inner membrane. The DNA sequence encoding a serine-type protease, similar to the lon protease gene of Escherichia coli, was cloned from the Arabidopsis genome. The expression product of this sequence demonstrated proteolytic activity against ORF239 in vitro, with features resembling the activity detected in mitochondrial inner membrane preparations. Antibodies generated against the overexpressed Lon homolog reduced proteolytic activity against ORF239 when added to mitochondrial extracts. Our data suggest that ORF239 was undetected in vegetative tissue due to rapid turnover by at least one mitochondrial protease that acts against ORF239 post-translationally. PMID:9668139

  3. Silencing of the Hsf gene, the transcriptional regulator of A. gambiae male accessory glands, inhibits the formation of the mating plug in mated females and disrupts their monogamous behaviour.

    PubMed

    Dottorini, Tania; Persampieri, Tania; Palladino, Pietro; Spaccapelo, Roberta; Crisanti, Andrea

    2012-11-01

    Discovering the molecular factors that shape the mating behaviour and the fertility of the mosquito Anopheles gambiae, the principal vector of human malaria, is regarded as critical to better understand its reproductive success as well as for identifying new leads for malaria control measures. In A. gambiae mating induces complex behavioural and physiological changes in the females, including refractoriness to subsequent mating and induction of egg-laying. In other insects including Drosophila a group of proteins named Accessory gland proteins (Acps), produced by males and transferred with sperm to the female reproductive tract, have been implicated in this post-mating response. Although Acps represent a set of promising candidates for unravelling the mating physiology, their role in inducing behavioural changes in mated A. gambiae females remains largely unknown. In this work, we demonstrate that a down-regulation of a large fraction of Acp genes via silencing of the Acp regulating transcription factor Hsf, abolishes the formation of mating plug in mated females and fails to induce refractoriness of mated female to subsequent inseminations. A significant fraction of females mated to Hsf silenced males (66%) failed to receive the mating plug though seminal fluid had been transferred as documented by the presence of spermatozoa in the female sperm storage organ. Furthermore, nearly all females (95%) mated to HSF-silenced males were re-inseminated when exposed to males carrying EGPF marked sperm. Our findings provide evidence showing that Acp genes regulated by the transcription factor HSF play a key role in the function of the male accessory glands.

  4. Cytochemical Analysis of Pollen Development in Wild-Type Arabidopsis and a Male-Sterile Mutant.

    PubMed Central

    Regan, SM; Moffatt, BA

    1990-01-01

    Microsporogenesis has been examined in wild-type Arabidopsis thaliana and the nuclear male-sterile mutant BM3 by cytochemical staining. The mutant lacks adenine phosphoribosyltransferase, an enzyme of the purine salvage pathway that converts adenine to AMP. Pollen development in the mutant began to diverge from wild type just after meiosis, as the tetrads of microspores were released from their callose walls. The first indication of abnormal pollen development in the mutant was a darker staining of the microspore wall due to an incomplete synthesis of the intine. Vacuole formation was delayed and irregular in the mutant, and the majority of the mutant microspores failed to undergo mitotic divisions. Enzyme activities of alcohol dehydrogenase and esterases decreased in the mutant soon after meiosis and were undetectable in mature pollen grains of the mutant. RNA accumulation was also diminished. These results are discussed in relation to the possible role(s) of adenine salvage in pollen development. PMID:12354970

  5. Genome Barriers between Nuclei and Mitochondria Exemplified by Cytoplasmic Male Sterility

    PubMed Central

    Fujii, Sota; Toriyama, Kinya

    2008-01-01

    Since plants retain genomes of an extremely large size in mitochondria (200–2,400 kb), and mitochondrial protein complexes are comprised of chimeric structures of nuclear- and mitochondrial-encoded subunits, coordination of gene expression between the nuclei and mitochondria is indispensable for sound plant development. It has been well documented that the nucleus regulates organelle gene expression. This regulation is called anterograde regulation. On the other hand, recent studies have demonstrated that signals emitted from organelles regulate nuclear gene expression. This process is known as retrograde signaling. Incompatibility caused by genome barriers between a nucleus and foreign mitochondria destines the fate of pollen to be dead in cytoplasmic male sterility (CMS), and studies of CMS confirm that pollen fertility is associated with anterograde/retrograde signaling. This review summarizes the current perspectives in CMS and fertility restoration, mainly from the viewpoint of anterograde/retrograde signaling. PMID:18625609

  6. Behaviour of Arctic charr Salvelinus alpinus during an induced mating season in captivity: how male relative size influences male behavioural investment and female preference over time.

    PubMed

    Bolgan, M; O'Brien, J; Picciulin, M; Manning, L; Gammell, M

    2016-12-20

    The behaviour of sexually mature Arctic charr Salvelinus alpinus specimens (fifth farm generation) was observed in captivity for four consecutive days. Only agonistic interactions between males of different size were facilitated on the first 2 days, while both agonistic and courtship interactions were possible from the third day up to the end of the experiment. The reliability of behavioural analysis was assessed in order to reduce the possibility of observer errors within the generated datasets. The behavioural investment of big males, small males and females was analysed using general linear models (two-way repeated measures ANOVAs with time and male size as factors). A peak in the agonistic interactions between males occurred during the first day of interactions, where the agonistic investment of big males was significantly higher than that of small males. This resulted in an increased investment in submissive behaviour by the small males, who consistently performed submissive behaviours from the second day of interactions up to the end of the trial. Big males were found to invest significantly more than small males in courtship behaviours for the duration of the trial. Even though females performed inter-sexual behaviours towards both big and small males for the entire observation period, female interaction rate towards big males was higher than towards small males. This study suggests that both male investment in mating behaviour and female preference might be related to male characteristics such as body length and that S. alpinus behavioural patterns and mate choice cues might be strongly context-related and characterized by high levels of behavioural plasticity (i.e. presence-absence of certain behavioural units or potential reversal of a mate choice cue) within the same species. Finally, in light of this, some conservation measures are discussed. In particular, effective management plans should take into account the high level of behavioural plasticity

  7. Intergenerational effects of parental personality and relationship traits on mate choice among gay male and lesbian offspring.

    PubMed

    van Eeden-Moorefield, Brad; Lindsey, Elizabeth W

    2005-01-01

    Data from 33 lesbian and 54 gay male cohabiting couples were used to examine the relation between parental identification and mate selection. Theories of mate selection and parental identification are reviewed. Effects of gender and sexual orientation as they relate to parental identification and mate selection in gay male and lesbian couples also are reviewed. The results demonstrate significant associations between the similarity of perceived parental personality and relationship styling traits with those of the partner. Socio-economic status, age, and culture also were significantly associated between parents and partners. Taken together, the results demonstrate little support for any specific theory and allude to the need for further research in this area. Limitations and implications are discussed.

  8. Impact of body reserves on energy expenditure, water flux, and mating success in breeding male northern elephant seals.

    PubMed

    Crocker, Daniel E; Houser, Dorian S; Webb, Paul M

    2012-01-01

    In capital breeders, individual differences in body size and condition can impact mating effort and success. In addition to the collateral advantages of large body size in competition, large nutrient reserves may offer advantages in endurance rivalry and enable the high rates of energy expenditure associated with mating success. We examined the impacts of body reserves and dominance rank on energy expenditure, water flux, mating success, and breeding tenure in the adult male northern elephant seal, a polygynous, capital breeder. Adult males expended energy at a rate of 159 ± 49 MJ d (-1), which is equivalent to 3.1 times the standard metabolic rate predicted by Kleiber's equation. Despite high rates of energy expenditure and a long fasting duration, males spared lean tissue effectively, deriving a mean of 7% of their metabolism from protein catabolism. Body composition had a strong impact on the ability to spare lean tissue during breeding. When controlling for body size, energy expenditure, depletion of blubber reserves, and water efflux were significantly greater in alpha males than in subordinate males. Large body size was associated with increased reproductive effort, tenure on shore, dominance rank, and reproductive success. Terrestrial locomotion and topography appeared to strongly influence energy expenditure. Comparisons with conspecific females suggest greater total seasonal reproductive effort in male northern elephant seals when controlling for the effects of body mass. In polygynous capital breeding systems, male effort may be strongly influenced by physiological state and exceed that of females.

  9. Juvenile Rank Can Predict Male-Typical Adult Mating Behavior in Female Sheep Treated Prenatally with Testosterone1

    PubMed Central

    Roberts, Eila K.; Flak, Jonathan N.; Ye, Wen; Padmanabhan, Vasantha; Lee, Theresa M.

    2009-01-01

    Previous research with female sheep indicates that exposure to excess testosterone for 60 days (from Gestational Days 30–90 of the 147-day gestation) leads to virilized genitalia, severe neuroendocrine deficits, as well as masculinization and defeminization of sexual behavior (T60 females). In contrast, 30 days of testosterone exposure (Gestational Days 60–90) produce animals with female-typical genitalia, less severe neuroendocrine alterations, and variable gender patterns of sexual behavior (T30 females). Variation in adult sexual behavior of male ungulates is influenced by early social experience, but this has never been tested in females. Here we investigate the influence of rank in the dominance hierarchy on the expression of adult sexual behavior in females. Specifically, we hypothesized that juvenile rank would predict the amount of male- and female-typical mating behavior exhibited by adult female sheep. This hypothesis was tested in two treatment groups and their controls (group 1: T60 females; group 2: T30 females). Dominance hierarchies were determined by observing competition over resources. Both groups of prenatal testosterone-treated females were higher ranking than controls (T60: P = 0.05; T30: P < 0.01). During the breeding season, both T60 and T30 females exhibited more male-typical mating behavior than did controls; however, the T30 animals also exhibited female-typical behavior. For the T60 group, prenatal treatment, not juvenile rank, best predicted male-typical sex behavior (P = 0.007), while juvenile rank better predicted male mating behavior for the T30 group (P = 0.006). Rank did not predict female mating behavior in the hormone-treated or control ewes. We conclude that the effect of prenatal testosterone exposure on adult male-specific but not female-specific mating behavior is modulated by juvenile social experiences. PMID:19122184

  10. Dominance, access to females, and mating success among coresident male mantled howlers (Alouatta palliata) at La Pacifica, Costa Rica.

    PubMed

    Corewyn, Lisa C

    2015-04-01

    The priority-of-access (POA) model posits that high dominance rank increases male mating success by increasing access to fertile females. However, the relationship between rank, access to females, and subsequent mating success is variable in primates, and there are few studies representing Neotropical taxa. The purpose here was to test the parameters of the POA model in an asynchronously breeding Neotropical primate, Alouatta palliata, to contribute to our understanding of the relationship between dominance and reproductive strategies in platyrrhines. I collected data on adult males within two large, multimale-multifemale groups exhibiting clear dominance hierarchies at La Pacifica, Costa Rica. Females were classified as sexually receptive (SR) or potentially cycling (PC) based on behavioral and birth data. Access to mates was measured based on total time in proximity to SR/PC females, and mating success was measured based on copulation frequency. Results did not support the predictions of the POA model in that first-ranked males maintained lower than expected time in proximity to SR females, did not consistently maintain the greatest proportion of time in proximity to PC females, obtained lower than expected copulation rates, and did not obtain the highest copulation rates compared to subordinates in either group. Deviations from the POA model were significantly affected by varying operational sex ratios only when considering the lower numbers of available SR females in one group. Alternative reproductive tactics by subordinate males such as tolerance by first-ranked males appeared to be operating, allowing subordinates to obtain mating success when they would otherwise be unable to do so. The study also highlighted how factors such as operational sex ratio may limit the willingness or ability of dominant males to monopolize access to females, and can vary both within and between groups in a population.

  11. QTL involved in the partial restoration of male fertility of C-type cytoplasmic male sterility in maize.

    PubMed

    Kohls, Susanne; Stamp, Peter; Knaak, Carsten; Messmer, Rainer

    2011-07-01

    Partial restoration of male fertility limits the use of C-type cytoplasmic male sterility (C-CMS) for the production of hybrid seeds in maize. Nevertheless, the genetic basis of the trait is still unknown. Therefore, the aim to this study was to identify genomic regions that govern partial restoration by means of a QTL analysis carried out in an F(2) population (n = 180). This population was derived from the Corn Belt inbred lines B37C and K55. F(2)BC(1) progenies were phenotyped at three locations in Switzerland. Male fertility was rated according to the quality and number of anthers as well as the anthesis-silking interval. A weak effect of environment on the expression of partial restoration was reflected by high heritabilities of all fertility-related traits. Partial restoration was inherited like an oligogenic trait. Three major QTL regions were found consistently across environments in the chromosomal bins 2.09, 3.06 and 7.03. Therefore, a marker-assisted counter-selection of partial restoration is promising. Minor QTL regions were found on chromosomes 3, 4, 5, 6 and 8. A combination of partial restorer alleles at different QTL can lead to full restoration of fertility. The maternal parent was clearly involved in the partial restoration, because the restorer alleles at QTL in bins 2.09, 6.04 and 7.03 originated from B37. The three major QTL regions collocated with other restorer genes of maize, a phenomenon, which seems to be typical for restorer genes. Therefore, a study of the clusters of restorer genes in maize could lead to a better understanding of their evolution and function. In this respect, the long arm of chromosome 2 is particularly interesting, because it harbors restorer genes for the three major CMS systems (C, T and S) of maize.

  12. Male mate location behaviour and encounter sites in a community of tropical butterflies: taxonomic and site associations and distinctions.

    PubMed

    Tiple, Ashish D; Padwad, Sonali V; Dapporto, Leonardo; Dennis, Roger L H

    2010-12-01

    Male mate location behaviour and encounter sites have been studied in 72 butterfly species at Nagpur, India, and related to taxonomy, morphology, habitat and population parameters. Species can be placed in three broad classes of mate location behaviour: invariant patrolling, invariant perching, and perch-patrol, the latter associated with increasing site fidelity, territorial defence and male assemblages. Significant taxonomic differences occur, closely related species tending to share mate location behaviours. Morphological differences are found with heavier and larger butterflies displaying greater site fidelity and territorial defence, and differences occur between individuals of species which both perch and patrol. Invariant patrolling is particularly associated with tracks through vegetation, host planttrack distributions, and high female to male numbers observed on transects; invariant perching is linked more to edge features than patrolling, and to lower population counts on transects. Species which perch-patrol, defend territories and establish male assemblages are associated with more complex vegetation structures, and have encounter sites at vegetation edges, landforms and predictable resource (host plant) concentrations. Attention is drawn to the importance of distinctive mate encounter sites for the conservation of butterfly species' habitats.

  13. The effect of disease on the evolution of females and the genetic basis of sex in populations with cytoplasmic male sterility.

    PubMed

    Miller, Ian; Bruns, Emily

    2016-02-10

    The evolution of separate males and females is an important evolutionary transition that has occurred multiple times in flowering plants. While empirical studies have stressed the potential importance of natural enemies and organismal interactions in the evolution of separate sexes, there has been no treatment of natural enemies in the theoretical literature. We investigated the effects of disease on the evolution of females in gynodioecious populations composed of females and hermaphrodites, where sex is determined by the interaction of cytoplasmic male sterility (CMS) and nuclear restorer genes. When females are significantly more resistant than hermaphrodites, disease drives an increase in the frequency of females and sex determination becomes nuclear, creating the pre-conditions for the evolution of separate males and females. However, when females are only moderately more resistant, disease drives changes in the frequency of CMS and restorer alleles, but has little effect on the frequency of females. We discuss our results in the context of the evolution of mating systems and cyto-nuclear epistasis.

  14. The effect of disease on the evolution of females and the genetic basis of sex in populations with cytoplasmic male sterility

    PubMed Central

    Miller, Ian; Bruns, Emily

    2016-01-01

    The evolution of separate males and females is an important evolutionary transition that has occurred multiple times in flowering plants. While empirical studies have stressed the potential importance of natural enemies and organismal interactions in the evolution of separate sexes, there has been no treatment of natural enemies in the theoretical literature. We investigated the effects of disease on the evolution of females in gynodioecious populations composed of females and hermaphrodites, where sex is determined by the interaction of cytoplasmic male sterility (CMS) and nuclear restorer genes. When females are significantly more resistant than hermaphrodites, disease drives an increase in the frequency of females and sex determination becomes nuclear, creating the pre-conditions for the evolution of separate males and females. However, when females are only moderately more resistant, disease drives changes in the frequency of CMS and restorer alleles, but has little effect on the frequency of females. We discuss our results in the context of the evolution of mating systems and cyto-nuclear epistasis. PMID:26865308

  15. Proteomic analyses of male contributions to honey bee sperm storage and mating

    PubMed Central

    Collins, A M; Caperna, T J; Williams, V; Garrett, W M; Evans, J D

    2006-01-01

    Honey bee (Apis mellifera L.) queens mate early in life and store sperm for years. Male bees likely contribute significantly to sperm survival. Proteins were extracted from seminal vesicles and semen of mature drones, separated by electrophoresis, and analysed by peptide mass fingerprinting. Computer searches against three databases, general species, honey bees and fruit flies, were performed. Spectra were used to query the recently generated honey bee genome protein list as well as general species and fruit fly databases. Of the 69 unique honey bee proteins found, 66 are also in Drosophila melanogaster. Two proteins only matched honey bee genes and one is a widespread protein lost from the fly genome. There is over-representation of genes implicated in the glycolysis pathway. Metabolism-associated proteins were found primarily in the seminal vesicle. Male accessory gland proteins as identified in Drosophila rarely had orthologs among proteins found in the honey bee. A complete listing of gel spots chosen including honey bee genome matches and Mascot searches of MALDI-TOF results with statistics is in the Supplementary table. MALDI-TOF spectra and more complete Mascot peptide mass fingerprinting data are available on request. Supplementary figs 1–3 show the stained protein gels. PMID:17069630

  16. Mating success and body condition not related to foraging specializations in male fur seals

    PubMed Central

    Cherel, Y.; Guinet, C.; Arnould, J. P. Y.

    2016-01-01

    Individual specialization is widespread among wild populations. While its fitness consequences are central in predicting the ecological and evolutionary trajectories of populations, they remain poorly understood. Long-term individual foraging specializations occur in male Antarctic (Arctocephalus gazella) and Australian (A. pusillus doriferus) fur seals. Strong selective pressure is expected in these highly dimorphic and polygynous species, raising the question of the fitness payoffs associated with different foraging strategies. We investigated the relationship between individual isotopic niche (a proxy of foraging specialization), body size and condition, and an index of reproductive success (harem size) in territorial males. Individuals varied greatly in their skin and fur isotopic values reflecting a range of foraging strategies within the two populations. However, in both species, isotopic niche was not correlated to body size, condition or mating success (R2/ρ < 0.06). Furthermore, no foraging niche was predominant in either species, which would have indicated a substantial long-term fitness benefit of a particular strategy via a higher survival rate. These results suggest that the fitness consequences of a foraging strategy depend not only on the quality of prey and feeding habitat but also on an individual's hunting efficiency and skills. PMID:27493771

  17. Effects of surgical and chemical sterilization on the behavior of free-roaming male dogs in Puerto Natales, Chile.

    PubMed

    Garde, E; Pérez, G E; Vanderstichel, R; Dalla Villa, P F; Serpell, J A

    2016-01-01

    Population management of free-roaming domestic dogs (Canis lupus familiaris) is of interest due to the threat these animals pose to people, other animals and the environment. Current sterilization procedures for male dogs include surgical and chemical methods. However, little is known about how these procedures affect their behavior. The primary objective of this study was to investigate changes in selected behaviors following chemical and surgical sterilization in a male free-roaming dog (FRD) population in southern Chile. We also examined the association between serum testosterone levels and behaviors thought to be influenced by circulating androgens. A total of 174 dogs were randomly assigned to either a surgical or chemical sterilization group, or a control group. At the onset of the intervention period, 119 dogs remained and 102 dogs successfully completed the study. Each dog was monitored pre- and post-intervention using video recordings, GPS collars, and blood samples for the measurement of testosterone. Analysis of behavior revealed that surgically castrated dogs showed no reduction of sexual activity or aggression when compared to their pre-intervention behavior. Chemically sterilized dogs showed a statistically significant increase in dog-directed aggression, but no change in sexual activity. There was no change in home range size in any groups between the pre- and post-intervention measurement. We found no consistent association between levels of serum testosterone concentration and behavioral changes in any of the groups. This study presents the first detailed behavioral observations following surgical and chemical sterilization in male FRDs. The information generated is highly relevant to communities struggling with the control of FRDs. Complementary studies to further our understanding of the effects of male sterilization on the behavioral and reproductive dynamics of FRD populations are needed.

  18. Tapetum-specific expression of a cytoplasmic orf507 gene causes semi-male sterility in transgenic peppers

    PubMed Central

    Ji, Jiao-Jiao; Huang, Wei; Li, Zheng; Chai, Wei-Guo; Yin, Yan-Xu; Li, Da-Wei; Gong, Zhen-Hui

    2015-01-01

    Though cytoplasmic male sterility (CMS) in peppers is associated with the orf507 gene, definitive and direct evidence that it directly causes male sterility is still lacking. In this study, differences in histochemical localization of anther cytochrome c oxidase between the pepper CMS line and maintainer line were observed mainly in the tapetal cells and tapetal membrane. Inducible and specific expression of the orf507 gene in the pepper maintainer line found that transformants were morphologically similar to untransformed and transformed control plants, but had shrunken anthers that showed little dehiscence and fewer pollen grains with lower germination rate and higher naturally damaged rate. These characters were different from those of CMS line which does not produce any pollen grains. Meanwhile a pollination test using transformants as the male parent set few fruit and there were few seeds in the limited number of fruits. At the tetrad stage, ablation of the tapetal cell induced by premature programmed cell death (PCD) occurred in the transformants and the microspores were distorted and degraded at the mononuclear stage. Stable transmission of induced semi-male sterility was confirmed by a test cross. In addition, expression of orf507 in the maintainer lines seemed to inhibit expression of atp6-2 to a certain extent, and lead to the increase of the activity of cytochrome c oxidase and the ATP hydrolysis of the mitochondrial F1Fo-ATP synthase. These results introduce the premature PCD caused by orf507 gene in tapetal cells and semi-male sterility, but not complete male sterility. PMID:25954296

  19. Flavonoid wing pigments increase attractiveness of female common blue (Polyommatus icarus) butterflies to mate-searching males

    NASA Astrophysics Data System (ADS)

    Burghardt, Frank; Knüttel, Helge; Becker, Mechthild; Fiedler, K.

    Common blue butterflies (Polyommatus icarus) sequester flavonoids from their larval host plants and allocate these UV-absorbing pigments to the wings. In field experiments using dummies constructed from female butterflies, mate-searching males inspected flavonoid-rich dummies more intensively than those with little or no flavonoids. Flavonoid content as signalled by UV-wing pattern may indicate ontogenetically determined female quality or enhance detectability to males.

  20. Interspecific amphiploid-derived alloplasmic male sterility with defective anthers, narrow disk florets, and small ray flowers in sunflower

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The cytoplasmic male-sterility (CMS)/fertility-restoration system is important for hybrid sunflower (Helianthus annuus L.) seed production. Two novel alloplasmic CMSs, designated CMS GRO1 and CMS MAX3 with defective anthers, narrow disk florets with no swollen corolla, and short, narrow ray flowers,...

  1. Comparative studies of mitochondrial proteomics reveal an intimate protein network of male sterility in wheat (Triticum aestivum L.).

    PubMed

    Wang, Shuping; Zhang, Gaisheng; Zhang, Yingxin; Song, Qilu; Chen, Zheng; Wang, Junsheng; Guo, Jialin; Niu, Na; Wang, Junwei; Ma, Shoucai

    2015-10-01

    Plant male sterility has often been associated with mitochondrial dysfunction; however, the mechanism in wheat (Triticum aestivum L.) has not been elucidated. This study set out to probe the mechanism of physiological male sterility (PHYMS) induced by the chemical hybridizing agent (CHA)-SQ-1, and cytoplasmic male sterility (CMS) of wheat at the proteomic level. A total of 71 differentially expressed mitochondrial proteins were found to be involved in pollen abortion and further identified by MALDI-TOF/TOF MS (matrix-assisted laser desorption/ionization-time of fight/time of flight mass spectrometry). These proteins were implicated in different cellular responses and metabolic processes, with obvious functional tendencies toward the tricarboxylic acid cycle, the mitochondrial electron transport chain, protein synthesis and degradation, oxidation stress, the cell division cycle, and epigenetics. Interactions between identified proteins were demonstrated by bioinformatics analysis, enabling a more complete insight into biological pathways involved in anther abortion and pollen defects. Accordingly, a mitochondria-mediated male sterility protein network in wheat is proposed; this network was further confirmed by physiological data, RT-PCR (real-time PCR), and TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling) assay. The results provide intriguing insights into the metabolic pathway of anther abortion induced by CHA-SQ-1 and also give useful clues to identify the crucial proteins of PHYMS and CMS in wheat.

  2. Sterility introduced by release of genetically altered males to a domestic population of Aedes aegypti at the Kenya coast.

    PubMed

    McDonald, P T; Hausermann, W; Lorimer, N

    1977-05-01

    The release of males heterozygous for one or two sex-linked translocations was effective in introducing a high level of sterility into a domestic population of Aedes aegypti at a Rabai village. The effect of the releases continued for several weeks after the release period.

  3. Capture of Anastrepha suspensa and sterile male Ceratitis capitata (Diptera: Tephritidae) in multilure traps versus phase 4 traps

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field trials were conducted in south Florida to compare capture of wild Caribbean fruit flies, Anastrepha suspensa (Loew), and sterile male Mediterranean fruit flies, Ceratitis capitata (Wiedemann), in Multilure traps, which are McPhail-type traps that use an aqueous solution to retain attracted fli...

  4. Characterization of an RNase Z nonsense mutation identified exclusively in environment-conditioned genic male sterile rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two-line system that is becoming more and more important for development of rice hybrids depends on environmentally conditioned genic male sterility (EGMS) due to either photoperiod (PGMS), or temperature (TGMS), or both (PTGMS). Up to 18 EGMS genes have been mapped with two being cloned, but contro...

  5. Genetic analysis and molecular mapping of an Rf gene from Helianthus angustifolius for a new cytoplasmic male-sterile line

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The combination of cytoplasmic male-sterile (CMS) and the corresponding fertility restoration genes (Rf) is a critical tool in large-scale hybrid seed production of sunflower. A new CMS line 514A, derived from H. tuberosus / 7718B, was obtained from a scientific exchange with the Liaoning Academy of...

  6. Enhancing mating performance after juvenile hormone treatment in Anastrepha fraterculus (Diptera:Tephritidae): a differential response in males and females acts as a physiological sexing system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Methoprene treatment can reduce the time required for sexual maturation in Anastrepha fraterculus (Diptera: Tephritidae) (Wiedemann) males under laboratory conditions, supporting its use as a treatment for sterile males within the context of the Sterile Insect Technique (SIT). Here we evaluated sexu...

  7. Evaluation of strategies for the release of male sea lampreys (Petromyzon marinus) in Lake Superior for a proposed sterile-male-release program

    USGS Publications Warehouse

    Kaye, C.A.; Heinrich, J.W.; Genovese, J.H.; Hanson, L.H.; McDonald, R.B.; Slade, J.W.; Swink, W.D.

    2003-01-01

    Successful implementation of a sea lamprey (Petromyzon marinus) control technique that uses sterilized males to reduce reproduction presently depends on the importation of large numbers of males outside of the target population. Strategies were examined for releasing male sea lampreys from Lakes Michigan and Huron into the Lake Superior spawning population and the ability of these introduced males to compete with resident males and spawn with resident females. During 1987, 553 (9%) of 6,324 imported fertile males released at 12 shoreline and one offshore site in Lake Superior were recaptured. Most remained within 20 km of the release site and entered the first stream encountered. During 1988, 393 (18%) of 2,208 imported fertile males released directly into three spawning rivers were recaptured. In both cases, animals released early during the spawning run were more likely to be recaptured than those released later. Introduced males successfully competed with resident males and spawned with resident females. Demonstrating that male sea lampreys could reproduce successfully when relocated supported subsequent large-scale field trials of the sterile-male-release technique.

  8. Registration of N614, A3N615, N616, and N617 Shattercane Genetic Stocks with cytoplasmic or nuclear male-sterility and juicy or dry midribs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four shattercane [Sorghum bicolor subsp. drummondii (Nees ex Steud) de Wet & Harlan] genetic stocks, N614, A3N615, N616, N617 (Reg. No. XXX, PI 665683 to 665686), with A3 cytoplasmic male-sterility or nuclear male-sterility gene ms3 containing either juicy (dd) or dry (DD) culms were developed joint...

  9. Cytological and comparative proteomic analyses on male sterility in Brassica napus L. induced by the chemical hybridization agent monosulphuron ester sodium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Male sterility induced by a chemical hybridization agent (CHA) is an important tool for utilizing crop heterosis. Monosulphuron ester sodium (MES), a new acetolactate synthase-inhibitor herbicide belonging to the sulphonylurea family, has been developed as an effective CHA to induce male sterility i...

  10. Bioreplicated visual features of nanofabricated buprestid beetle decoys evoke stereotypical male mating flights

    PubMed Central

    Domingue, Michael J.; Lakhtakia, Akhlesh; Pulsifer, Drew P.; Hall, Loyal P.; Badding, John V.; Bischof, Jesse L.; Martín-Palma, Raúl J.; Imrei, Zoltán; Janik, Gergely; Mastro, Victor C.; Hazen, Missy; Baker, Thomas C.

    2014-01-01

    Recent advances in nanoscale bioreplication processes present the potential for novel basic and applied research into organismal behavioral processes. Insect behavior potentially could be affected by physical features existing at the nanoscale level. We used nano-bioreplicated visual decoys of female emerald ash borer beetles (Agrilus planipennis) to evoke stereotypical mate-finding behavior, whereby males fly to and alight on the decoys as they would on real females. Using an industrially scalable nanomolding process, we replicated and evaluated the importance of two features of the outer cuticular surface of the beetle’s wings: structural interference coloration of the elytra by multilayering of the epicuticle and fine-scale surface features consisting of spicules and spines that scatter light into intense strands. Two types of decoys that lacked one or both of these elements were fabricated, one type nano-bioreplicated and the other 3D-printed with no bioreplicated surface nanostructural elements. Both types were colored with green paint. The light-scattering properties of the nano-bioreplicated surfaces were verified by shining a white laser on the decoys in a dark room and projecting the scattering pattern onto a white surface. Regardless of the coloration mechanism, the nano-bioreplicated decoys evoked the complete attraction and landing sequence of Agrilus males. In contrast, males made brief flying approaches toward the decoys without nanostructured features, but diverted away before alighting on them. The nano-bioreplicated decoys were also electroconductive, a feature used on traps such that beetles alighting onto them were stunned, killed, and collected. PMID:25225359

  11. Heaven It's My Wife! Male Canaries Conceal Extra-Pair Courtships but Increase Aggressions When Their Mate Watches

    PubMed Central

    Ung, Davy; Amy, Mathieu; Leboucher, Gérard

    2011-01-01

    Many animals live in a communication network, an environment where individuals can obtain information about competitors or potential mates by observing interactions between conspecifics. In such an environment, interactants might benefit by changing their signalling behaviour in the presence of an audience. This audience effect seems widespread among species, has been observed during various types of interaction (e.g. intra-sexual vs. inter-sexual interaction) and varies according to the social context (e.g. gender, hierarchical or mating status of the audience). However, the way individuals might adapt their signalling behaviour to a combination of these factors remains poorly understood. To address this question, we studied how the presence of an audience affects the behaviour of male domestic canaries Serinus canaria during two types of interactions: (i) an extra-pair interaction and (ii) a male-male competition for food. Males were observed under three conditions: (a) in the absence of audience, (b) in the presence of their mate or (c) of a familiar female. Our results show that male domestic canaries minutely adapt their courting and agonistic behaviours to a combination of: (i) the type of interaction (extra-pair interaction/male-male competition), (ii) the social context (mate, familiar female or nobody in audience) and (iii) the behaviours of both the audience and the interactant. These results highlight the ability of animals to subtly adapt their behaviour to the social environment. This also raises questions about the cognitive foundations and evolution of these processes especially considering that canaries are known neither for having high cognitive abilities nor for being a typical example for the social intelligence hypothesis. PMID:21857945

  12. Mate vocal recognition in the Scopoli's shearwater Calonectris diomedea: do females and males share the same acoustic code?

    PubMed

    Curé, Charlotte; Mathevon, Nicolas; Aubin, Thierry

    2016-07-01

    Vocal recognition is an important process allowing partners' reunion in most seabirds. Although the acoustic basis of this recognition has been explored in several species, only a few studies have experimentally tested the acoustic coding-decoding strategy used for mate identification. Here, we investigated mate recognition in the Scopoli's shearwater (Calonectris diomedea) by conducting playbacks of calls with modified acoustic features. We showed that females and males in a seabird species with a moderate vocal dimorphism are likely to share the same coding-decoding rule for vocal mate identification. Specifically, a disruption of call temporal structure prevented mate recognition in both sexes, in line with the parameters previously identified as supporting an individual signature. Modifications of spectral cues and envelope structure also impaired recognition, but at a lesser extent: almost half of the tested males and females were still able to recognise their partner. It is likely that this equal ability of female and male Scopoli's shearwaters to vocally recognise their partner could be found in other seabirds.

  13. Transposon Tagging of a Male-Sterility, Female-Sterility Gene, St8, Revealed that the Meiotic MER3 DNA Helicase Activity Is Essential for Fertility in Soybean

    PubMed Central

    Baumbach, Jordan; Pudake, Ramesh N.; Johnson, Callie; Kleinhans, Kaylin; Ollhoff, Alexandrea; Palmer, Reid G.; Bhattacharyya, Madan K.; Sandhu, Devinder

    2016-01-01

    The W4 locus in soybean encodes a dihydroflavonol-4-reductase (DFR2) that regulates pigmentation patterns in flowers and hypocotyl. The mutable w4-m allele that governs variegated flowers has arisen through insertion of a CACTA-type transposable element, Tgm9, in DFR2. In the w4-m line, reversion from variegated to purple flower indicates excision of Tgm9, and its insertion at a new locus. Previously, we have identified a male-sterile, female-sterile mutant among the selfed progenies of a revertant plant carrying only purple flowers. Co-segregation between Tgm9 and the sterility phenotype suggested that the mutant was generated by insertion of Tgm9 at the St8 locus. The transposon was localized to exon 10 of Glyma.16G072300 that shows high identity to the MER3 DNA helicase involved in crossing over. Molecular analysis of fertile branches from two independent revertant plants confirmed precise excision of Tgm9 from the st8 allele, which restored fertility. In soybean, the gene is expressed in flower-buds, trifoliate leaves and stem. Phylogenetic analysis placed St8 in a clade with the Arabidopsis and rice MER3 suggesting that St8 is most likely the orthologous MER3 soybean gene. This study established the utility of Tgm9 in gene identification as well as in forward and reverse genetics studies. PMID:26930200

  14. Organelle Simple Sequence Repeat Markers Help to Distinguish Carpelloid Stamen and Normal Cytoplasmic Male Sterile Sources in Broccoli.

    PubMed

    Shu, Jinshuai; Liu, Yumei; Li, Zhansheng; Zhang, Lili; Fang, Zhiyuan; Yang, Limei; Zhuang, Mu; Zhang, Yangyong; Lv, Honghao

    2015-01-01

    We previously discovered carpelloid stamens when breeding cytoplasmic male sterile lines in broccoli (Brassica oleracea var. italica). In this study, hybrids and multiple backcrosses were produced from different cytoplasmic male sterile carpelloid stamen sources and maintainer lines. Carpelloid stamens caused dysplasia of the flower structure and led to hooked or coiled siliques with poor seed setting, which were inherited in a maternal fashion. Using four distinct carpelloid stamens and twelve distinct normal stamens from cytoplasmic male sterile sources and one maintainer, we used 21 mitochondrial simple sequence repeat (mtSSR) primers and 32 chloroplast SSR primers to identify a mitochondrial marker, mtSSR2, that can differentiate between the cytoplasm of carpelloid and normal stamens. Thereafter, mtSSR2 was used to identify another 34 broccoli accessions, with an accuracy rate of 100%. Analysis of the polymorphic sequences revealed that the mtSSR2 open reading frame of carpelloid stamen sterile sources had a deletion of 51 bases (encoding 18 amino acids) compared with normal stamen materials. The open reading frame is located in the coding region of orf125 and orf108 of the mitochondrial genomes in Brassica crops and had the highest similarity with Raphanus sativus and Brassica carinata. The current study has not only identified a useful molecular marker to detect the cytoplasm of carpelloid stamens during broccoli breeding, but it also provides evidence that the mitochondrial genome is maternally inherited and provides a basis for studying the effect of the cytoplasm on flower organ development in plants.

  15. Male Moth Songs Tempt Females to Accept Mating: The Role of Acoustic and Pheromonal Communication in the Reproductive Behaviour of Aphomia sociella

    PubMed Central

    Kindl, Jiří; Kalinová, Blanka; Červenka, Milan; Jílek, Milan; Valterová, Irena

    2011-01-01

    Background Members of the subfamily Galleriinae have adapted to different selective environmental pressures by devising a unique mating process. Galleriinae males initiate mating by attracting females with either chemical or acoustic signals (or a combination of both modalities). Six compounds considered candidates for the sex pheromone have recently been identified in the wing gland extracts of Aphomia sociella males. Prior to the present study, acoustic communication had not been investigated. Signals mediating female attraction were likewise unknown. Methodology/Principal Findings Observations of A. sociella mating behaviour and recordings of male acoustic signals confirmed that males initiate the mating process. During calling behaviour (stationary wing fanning and pheromone release), males disperse pheromone from their wing glands. When a female approaches, males cease calling and begin to produce ultrasonic songs as part of the courtship behaviour. Replaying of recorded courting songs to virgin females and a comparison of the mating efficiency of intact males with males lacking tegullae proved that male ultrasonic signals stimulate females to accept mating. Greenhouse experiments with isolated pheromone glands confirmed that the male sex pheromone mediates long-range female attraction. Conclusion/Significance Female attraction in A. sociella is chemically mediated, but ultrasonic communication is also employed during courtship. Male ultrasonic songs stimulate female sexual display and significantly affect mating efficiency. Considerable inter-individual differences in song structure exist. These could play a role in female mate selection provided that the female's ear is able to discern them. The A. sociella mating strategy described above is unique within the subfamily Galleriinae. PMID:22065997

  16. Changes in blood testosterone concentrations after surgical and chemical sterilization of male free-roaming dogs in southern Chile.

    PubMed

    Vanderstichel, R; Forzán, M J; Pérez, G E; Serpell, J A; Garde, E

    2015-04-01

    There is a growing interest in chemical sterilization as an alternative to surgical castration in large-scale sterilization campaigns to control canine populations. An important step toward understanding the short-term and long-term effects of chemical sterilants is to determine their impact on blood testosterone concentrations, particularly as these could influence dog behavior after treatment. A field trial was conducted with 118 free-roaming male dogs in the Chilean Patagonia, where 36 dogs were chemically sterilized using EsterilSol, 39 dogs were surgically castrated, and 43 dogs remained intact as controls. Blood testosterone levels were determined at four time periods: on enrollment 6 months before treatment (t-6m), at the time of treatment (t0, within one hour after surgical castration or chemical sterilization and during a concurrent 2-week period for the control group), four (t+4m), and six (t+6m) months after treatment. Intrinsic and temporal factors were evaluated; age was significantly associated with testosterone, where dogs 2- to 4-year-old had the highest testosterone concentrations (P = 0.036), whereas body weight and body condition scores were not associated with testosterone; testosterone concentration was not influenced by time of day, month, or season. After treatment (t+4m and t+6m), all of the surgically castrated dogs had testosterone concentrations below 1.0 ng/mL. On the basis of this cut point (<1 ng/mL), testosterone remained unchanged in 66% of the chemically sterilized dogs at both t+4m and t+6m; it remained low for 22% of dogs at both t+4m and t+6m; it was unchanged at t+4m but low at t+6m in 9% of dogs; and, it was low at t+4m but reverted back to unchanged at t+6m in one dog (3%). Incidentally, testosterone in chemically sterilized dogs increased dramatically within 1 hour of treatment (t0), more than doubling (131%) the concentration of control dogs at the time of treatment (t0), likely because of severe necrosis of

  17. MALE STERILITY1 Is Required for Tapetal Development and Pollen Wall Biosynthesis[W][OA

    PubMed Central

    Yang, Caiyun; Vizcay-Barrena, Gema; Conner, Katie; Wilson, Zoe A.

    2007-01-01

    The Arabidopsis thaliana MALE STERILITY1 (MS1) gene is critical for viable pollen formation and has homology to the PHD-finger class of transcription factors; however, its role in pollen development has not been fully defined. We show that MS1 transcription appears to be autoregulated by the wild-type MS1 transcript or protein. Using a functional green fluorescent protein (GFP) fusion to analyze the temporal and spatial expression of MS1, we demonstrate that the MS1:GFP protein is nuclear localized within the tapetum and is expressed in a developmentally regulated manner between late tetraspore and microspore release, then rapidly breaks down, probably by ubiquitin-dependent proteolysis. Absence of MS1 expression results in changes in tapetal secretion and exine structure. Microarray analysis has shown that 260 (228 downregulated and 32 upreglated) genes have altered expression in young ms1 buds. These genes are primarily associated with pollen wall and coat formation; however, a number of transcription factors and Cys proteases have also been identified as the putative primary regulatory targets of MS1. Ectopic expression of MS1 alters transcriptional regulation of vegetative gene expression, resulting in stunted plants with increased levels of branching, partially fertile flowers and an apparent increase in wall material on mature pollen. MS1 therefore plays a critical role in the induction of pollen wall and pollen coat materials in the tapetum and, ultimately, the production of viable pollen. PMID:18032629

  18. Genetics of incipient speciation in Drosophila mojavensis. I. Male courtship song, mating success, and genotype x environment interactions.

    PubMed

    Etges, William J; de Oliveira, Cássia Cardoso; Gragg, Erin; Ortíz-Barrientos, Daniel; Noor, Mohamed A F; Ritchie, Michael G

    2007-05-01

    Few studies have examined genotype by environment (GxE) effects on premating reproductive isolation and associated behaviors, even though such effects may be common when speciation is driven by adaptation to different environments. In this study, mating success and courtship song differences among diverging populations of Drosophila mojavensis were investigated in a two-environment quantitative trait locus (QTL) analysis. Baja California and mainland Mexico populations of D. mojavensis feed and breed on different host cacti, so these host plants were used to culture F2 males to examine host-specific QTL effects and GxE interactions influencing mating success and courtship songs. Linear selection gradient analysis showed that mainland females mated with males that produced songs with significantly shorter L(long)-IPIs, burst durations, and interburst intervals. Twenty-one microsatellite loci distributed across all five major chromosomes were used to localize effects of mating success, time to copulation, and courtship song components. Male courtship success was influenced by a single detected QTL, the main effect of cactus, and four GxE interactions, whereas time to copulation was influenced by three different QTLs on the fourth chromosome. Multiple-locus restricted maximum likelihood (REML) analysis of courtship song revealed consistent effects linked with the same fourth chromosome markers that influenced time to copulation, a number of GxE interactions, and few possible cases of epistasis. GxE interactions for mate choice and song can maintain genetic variation in populations, but alter outcomes of sexual selection and isolation, so signal evolution and reproductive isolation may be slowed in diverging populations. Understanding the genetics of incipient speciation in D. mojavensis clearly depends on cactus-specific expression of traits associated with courtship behavior and sexual isolation.

  19. Do males bite females' antennae to coerce copulation or to continue mate guarding in Oiceoptoma subrufum (Coleoptera: Silphinae)?

    PubMed

    Sumitomo, Hiroyuki; Shiraishi, Kyosuke; Hirota, Tadao

    2014-06-01

    In several species, males frequently immobilize females during copulation. In some species, female immobilization enables males to copulate with unwilling females, while in others, female immobilization prolongs postcopulatory guarding. Male carrion beetles often bite and pull hard on one of the female's antennae during copulatory mounting. Previous descriptive studies have hypothesized that antenna biting is important for postcopulatory guarding in Silphinae. Here, we observed the mating behavior of Oiceoptoma subrufum, to understand the roles of antenna-biting in the initiation and termination of copulation. We compared the success and duration of intromission and pre- and postcopulatory mounting duration between males that did and did not bite female antennae during copulatory mounting. The success and duration of intromission and precopulatory mounting duration were unaffected by antenna biting. However, antenna-biting males mounted females for longer after intromission compared to non-biting males. These results indicate that antenna biting contributes to postcopulatory guarding behavior, not coercive copulation, in O. subrufum.

  20. Natural Variation in the Strength and Direction of Male Mating Preferences for Female Pheromones in Drosophila melanogaster

    PubMed Central

    Pischedda, Alison; Shahandeh, Michael P.; Cochrane, Wesley G.; Cochrane, Veronica A.; Turner, Thomas L.

    2014-01-01

    Many animal species communicate using chemical signals. In Drosophila, cuticular hydrocarbons (CHCs) are involved in species and sexual identification, and have long been thought to act as stimulatory pheromones as well. However, a previous study reported that D. melanogaster males were more attracted to females that were lacking CHCs. This surprising result is consistent with several evolutionary hypotheses but is at odds with other work demonstrating that female CHCs are attractive to males. Here, we investigated natural variation in male preferences for female pheromones using transgenic flies that cannot produce CHCs. By perfuming females with CHCs and performing mate choice tests, we found that some male genotypes prefer females with pheromones, some have no apparent preference, and at least one male genotype prefers females without pheromones. This variation provides an excellent opportunity to further investigate the mechanistic causes and evolutionary implications of divergent pheromone preferences in D. melanogaster males. PMID:24489930

  1. DNA methylation changes in photoperiod-thermo-sensitive male sterile rice PA64S under two different conditions.

    PubMed

    Chen, Xiaojun; Hu, Jihong; Zhang, Hongyuan; Ding, Yi

    2014-03-01

    Epigenetic modification can occur at a high frequency in crop plants and might generate phenotypic variation without changes in DNA sequences. DNA methylation is an important epigenetic modification that may contribute to environmentally-induced phenotypic variations by regulating gene expression. Rice Photoperiod-Thermo-Sensitive Genic Male Sterile (PTGMS) lines can transform from sterility to fertility under lower temperatures and short-day (SD) conditions during anther development. So far, little is known about the DNA methylation variation of PTGMS throughout the genome in rice. In this study, we investigated DNA cytosine methylation alterations in the young panicles of PTGMS line PA64S under two different conditions using methylation sensitive amplified polymorphism (MSAP) method. Compared with the DNA methylation level of PA64S under lower temperatures and SD conditions (fertility), higher methylation was observed in PA64S (sterility). The sequences of 25 differentially amplified fragments were successfully obtained and annotated. Three methylated fragments, which are homologous to D2, NAD7 and psaA, were confirmed by bisulfite sequencing and their expression levels were also evaluated by qPCR. Real time quantitative PCR analysis revealed that five of the six selected methylated genes were downregulated in PA64S (sterility). These results suggested that DNA methylation may be involved in the sterility-fertility transition of PA64S under two different environmental conditions.

  2. Open Field Release of Genetically Engineered Sterile Male Aedes aegypti in Malaysia

    PubMed Central

    Raduan, Norzahira; Kwee Wee, Lim; Hong Ming, Wong; Guat Ney, Teoh; Rahidah A.A., Siti; Salman, Sawaluddin; Subramaniam, Selvi; Nordin, Oreenaiza; Hanum A.T., Norhaida; Angamuthu, Chandru; Marlina Mansor, Suria; Lees, Rosemary S.; Naish, Neil; Scaife, Sarah; Gray, Pam; Labbé, Geneviève; Beech, Camilla; Nimmo, Derric; Alphey, Luke; Vasan, Seshadri S.; Han Lim, Lee; Wasi A., Nazni; Murad, Shahnaz

    2012-01-01

    Background Dengue is the most important mosquito-borne viral disease. In the absence of specific drugs or vaccines, control focuses on suppressing the principal mosquito vector, Aedes aegypti, yet current methods have not proven adequate to control the disease. New methods are therefore urgently needed, for example genetics-based sterile-male-release methods. However, this requires that lab-reared, modified mosquitoes be able to survive and disperse adequately in the field. Methodology/Principal Findings Adult male mosquitoes were released into an uninhabited forested area of Pahang, Malaysia. Their survival and dispersal was assessed by use of a network of traps. Two strains were used, an engineered ‘genetically sterile’ (OX513A) and a wild-type laboratory strain, to give both absolute and relative data about the performance of the modified mosquitoes. The two strains had similar maximum dispersal distances (220 m), but mean distance travelled of the OX513A strain was lower (52 vs. 100 m). Life expectancy was similar (2.0 vs. 2.2 days). Recapture rates were high for both strains, possibly because of the uninhabited nature of the site. Conclusions/Significance After extensive contained studies and regulatory scrutiny, a field release of engineered mosquitoes was safely and successfully conducted in Malaysia. The engineered strain showed similar field longevity to an unmodified counterpart, though in this setting dispersal was reduced relative to the unmodified strain. These data are encouraging for the future testing and implementation of genetic control strategies and will help guide future field use of this and other engineered strains. PMID:22970102

  3. Increased vulnerability of hippocampal CA1 neurons to hypoperfusion in ataxia and male sterility (AMS) mouse.

    PubMed

    Liang, Xueyun; Nagai, Atsushi; Sheikh, Abdullah Md; Wang, Hui; Mitaki, Shingo; Araki, Asuka; Maruyama, Riruke; Harada, Takayuki

    2013-02-04

    The nna1 gene mutation is associated with spontaneous degeneration of cerebellar Purkinje cells and germ cells in Ataxia and Male Sterility (AMS) mouse. Since nna1 is also expressed in hippocampal neurons, we investigated their vulnerability to hypoperfusion in AMS mouse. Eight-week-old male wild type (WT) and AMS mice were subjected to bilateral common carotid artery occlusion (BCCAO) for 10 min and sacrificed 1, 3, 7 and 28 days after BCCAO. Nissl staining revealed the neuronal cell loss and pyknotic change in the CA1 of AMS mice. TUNEL(+) apoptotic cells were found in the area at 7 days in AMS mice. Bcl-2 mRNA and protein in WT hippocampus were increased, while they were not increased in AMS. Bax mRNA was increased in AMS. Moreover, Bax activation was immunohistochemically demonstrated only in AMS at 3 and 7 days after BCCAO. An oxidative DNA damage marker, 8-hydroxydeoxyguanosine-positive cells were increased in both strains at 1 day; decreased in WT at 3 days but remained high in AMS. BCCAO increased glutathione, an antioxidant, in WT, but not in AMS at 3 days. The mRNA level of mitochondrial uncoupling protein 2, a regulator of oxidative stress, was increased only in WT at 1 day. Nna1 mRNA was similarly expressed in WT and AMS, but the protein was undetectable in AMS. Thus, our results indicate the increased vulnerability of hippocampal CA1 neurons of AMS mice to cerebral hypoperfusion could be due to an imbalance between oxidative stress and antioxidative defense system.

  4. Reproductive traits and number of matings in males and females of Cerambyx welensii (Coleoptera: Cerambycidae) an emergent pest of oaks.

    PubMed

    Torres-Vila, L M; Mendiola-Diaz, F J; Conejo-Rodríguez, Y; Sánchez-González, Á

    2016-06-01

    The longhorn beetle Cerambyx welensii is an emerging pest involved in oak decline episodes, whose damage is increasingly reported in dehesa open woodlands. Knowledge of the reproductive biology of C. welensii is a crucial goal due to its new pest status. In this study, we assess the reproductive traits of both sexes in the laboratory (25°C and 60% relative humidity ). In females, body length was 44.9 ± 0.9 mm (mean ± SE), fecundity 132 ± 12 eggs, fertility 70 ± 1 %, longevity 70 ± 3 days, preoviposition period 2 ± 0.2 days, oviposition period 44 ± 3 days and postoviposition period 19 ± 3 days. Fecundity was positively correlated with female size, longevity and oviposition period. Daily fecundity was 3.0 ± 0.2 eggs/day and showed a fluctuating synovigenic pattern with a slight decreasing trend over time. Egg length was 4.24 ± 0.01 mm and egg volume 8.14 ± 0.04 mm3. Egg size was correlated with female size but the relative size of eggs was larger in smaller females. Incubation time was 13.9 ± 0.1 days and hatching did not depend on egg size. Neonate size was positively correlated with egg length. Females were polyandrous (more than 20 lifetime matings) but multiple mating did not increase fecundity, fertility or longevity. In males, body length was 43.7 ± 0.6 mm and longevity 52 ± 3 days. Unlike with females, longevity was positively correlated with male size. Males were polygynous (up to 30 lifetime matings) but mating history did not affect male longevity. Rather to the contrary, long-lived males mated more times because they had more mating chances. Lastly, C. welensii reproductive traits were compared with those other Cerambycidae species and discussed from an adaptive perspective. Our data will be useful to improve management of C. welensii in order to prevent or mitigate its impact in dehesa woodlands and other oak forests.

  5. Transcriptome Sequencing Analyses between the Cytoplasmic Male Sterile Line and Its Maintainer Line in Welsh Onion (Allium fistulosum L.)

    PubMed Central

    Liu, Qianchun; Lan, Yanping; Wen, Changlong; Zhao, Hong; Wang, Jian; Wang, Yongqin

    2016-01-01

    Cytoplasmic male sterility (CMS) is important for exploiting heterosis in crop plants and also serves as a model for investigating nuclear–cytoplasmic interaction. The molecular mechanism of cytoplasmic male sterility and fertility restoration was investigated in several important economic crops but remains poorly understood in the Welsh onion. Therefore, we compared the differences between the CMS line 64-2 and its maintainer line 64-1 using transcriptome sequencing with the aim of determining critical genes and pathways associated with male sterility. This study combined two years of RNA-seq data; there were 1504 unigenes (in May 2013) and 2928 unigenes (in May 2014) that were differentially expressed between the CMS and cytoplasmic male maintainer Welsh onion varieties. Known CMS-related genes were found in the set of differentially expressed genes and checked by qPCR. These genes included F-type ATPase, NADH dehydrogenase, cytochrome c oxidase, etc. Overall, this study demonstrated that the CMS regulatory genes and pathways may be associated with the mitochondria and nucleus in the Welsh onion. We believe that this transcriptome dataset will accelerate the research on CMS gene clones and other functional genomics research on A. fistulosum L. PMID:27376286

  6. A randomized, controlled, multicenter contraceptive efficacy clinical trial of the intravas device, a nonocclusive surgical male sterilization

    PubMed Central

    Lu, Wen-Hong; Liang, Xiao-Wei; Gu, Yi-Qun; Wu, Wei-Xiong; Bo, Li-Wei; Zheng, Tian-Gui; Chen, Zhen-Wen

    2014-01-01

    Because of unavoidable complications of vasectomy, this study was undertaken to assess the efficacy and safety of male sterilization with a nonobstructive intravas device (IVD) implanted into the vas lumen by a mini-surgical method compared with no-scalpel vasectomy (NSV). IVDs were categorized into two types: IVD-B has a tail used for fixing to the vas deferens (fixed wing) whereas IVD-A does not. A multicenter prospective randomized controlled clinical trial was conducted in China. The study was comprised of 1459 male volunteers seeking vasectomy who were randomly assigned to the IVD-A (n = 487), IVD-B (n = 485) or NSV (n = 487) groups and underwent operation. Follow-up included visits at the 3rd–6th and 12th postoperative months. The assessments of the subjects involved regular physical examinations (including general and andrological examinations) and semen analysis. The subjects’ partners also underwent monitoring for pregnancy by monthly interviews regarding menstruation and if necessary, urine tests. There were no significant differences in pregnancy rates (0.65% for IVD-A, 0 for IVD-B and 0.21% for NSV) among the three groups (P > 0.05). The cumulative rates of complications at the 12th postoperative month were zero, 0.9% and 1.7% in the three groups, respectively. In conclusion, IVD male sterilization exhibits a low risk of long-term adverse events and was found to be effective as a male sterilization method, similar to the NSV technique. IVD male sterilization is expected to be a novel contraceptive method. PMID:24589454

  7. The study and analysis of the mating behavior and sound production of male cicada Psalmocharias alhageos (Kol.) (Homoptera:Cicadidae) to make disruption in mating.

    PubMed

    Zamanian, H; Mehdipour, M; Ghaemi, N

    2008-09-01

    Psalmocharias alhageos is an important pest of vine in most parts of Iran, Afghanistan, Pakistan, southern areas of Russia, Turkey and Iraq. This cicada is spread in most provinces in Iran such as Esfahan, Hamedan, Qazvin, Markazi, Lorestan, Qom, Kerman, Tehran and Kordestan. In addition to vine, this insect damages some other fruit trees, such as apple, sour cherry, quince, peach, pomegranate and pear trees and some non-fruit trees, namely white poplar, ash, elm, eglantine, silk and black poplar trees. The nymphs of cicada damage the trees by feeding on root, adult insects on young bud and by oviposition under branch barks. Nourishing root by nymph leads to the weakness of the tree and hinder its growth. The high density oviposition of adult insects inside young barks causes withering of branches. The resulted damage on vine products is 40% which is one of the most important factors in product reduction in vineyard. This research was conducted in Takestan in Qazvin. It was conducted for the first time to study the behaviors of the mates of this vine cicada in order to manage it. Two systems were used to record the sound of male cicada called analog voice-recorder and digital voice recorder. To analyze the recorded sound of the male cicada we used of spectrum analyzer, digital storage oscilloscope and protens 7 computer softwares. We could call the attention of natural enemies an disturb the male insect's attracting sound by producing natural and artificial sound in the range of 1-6 kHz in two different ripeness status of the fruits and could prevent mating and oviposition of female cicadas.

  8. Audience effects in the Atlantic molly (Poecilia mexicana)–prudent male mate choice in response to perceived sperm competition risk?

    PubMed Central

    Ziege, Madlen; Mahlow, Kristin; Hennige-Schulz, Carmen; Kronmarck, Claudia; Tiedemann, Ralph; Streit, Bruno; Plath, Martin

    2009-01-01

    Background Multidirectional interactions in social networks can have a profound effect on mate choice behavior; e.g., Poecilia mexicana males show weaker expression of mating preferences when being observed by a rival. This may be an adaptation to reduce sperm competition risk, which arises because commonly preferred female phenotypes will receive attention also from surrounding males, and/or because other males can copy the focal male's mate choice. Do P. mexicana males indeed respond to perceived sperm competition risk? We gave males a choice between two females and repeated the tests under one of the following conditions: (1) an empty transparent cylinder was presented (control); (2) another ("audience") male inside the cylinder observed the focal male throughout the 2nd part, or (3) the audience male was presented only before the tests, but could not eavesdrop during the actual choice tests (non-specific sperm competition risk treatments); (4) the focal male could see a rival male interact sexually with the previously preferred, or (5) with the non-preferred female before the 2nd part of the tests (specific sperm competition risk treatments). Results The strength of individual male preferences declined slightly also during the control treatment (1). However, this decrease was more than two-fold stronger in audience treatment (2), i.e., with non-specific sperm competition risk including the possibility for visual eavesdropping by the audience male. No audience effect was found in treatments (3) and (5), but a weak effect was also observed when the focal male had seen the previously preferred female sexually interact with a rival male (treatment 4; specific sperm competition risk). Conclusion When comparing the two 'non-specific sperm competition risk' treatments, a very strong effect was found only when the audience male could actually observe the focal male during mate choice [treatment (2)]. This suggests that focal males indeed attempt to conceal their mating

  9. Transcriptional Profiles of Mating-Responsive Genes from Testes and Male Accessory Glands of the Mediterranean Fruit Fly, Ceratitis capitata

    PubMed Central

    Scolari, Francesca; Gomulski, Ludvik M.; Ribeiro, José M. C.; Siciliano, Paolo; Meraldi, Alice; Falchetto, Marco; Bonomi, Angelica; Manni, Mosè; Gabrieli, Paolo; Malovini, Alberto; Bellazzi, Riccardo; Aksoy, Serap; Gasperi, Giuliano; Malacrida, Anna R.

    2012-01-01

    Background Insect seminal fluid is a complex mixture of proteins, carbohydrates and lipids, produced in the male reproductive tract. This seminal fluid is transferred together with the spermatozoa during mating and induces post-mating changes in the female. Molecular characterization of seminal fluid proteins in the Mediterranean fruit fly, Ceratitis capitata, is limited, although studies suggest that some of these proteins are biologically active. Methodology/Principal Findings We report on the functional annotation of 5914 high quality expressed sequence tags (ESTs) from the testes and male accessory glands, to identify transcripts encoding putative secreted peptides that might elicit post-mating responses in females. The ESTs were assembled into 3344 contigs, of which over 33% produced no hits against the nr database, and thus may represent novel or rapidly evolving sequences. Extraction of the coding sequences resulted in a total of 3371 putative peptides. The annotated dataset is available as a hyperlinked spreadsheet. Four hundred peptides were identified with putative secretory activity, including odorant binding proteins, protease inhibitor domain-containing peptides, antigen 5 proteins, mucins, and immunity-related sequences. Quantitative RT-PCR-based analyses of a subset of putative secretory protein-encoding transcripts from accessory glands indicated changes in their abundance after one or more copulations when compared to virgin males of the same age. These changes in abundance, particularly evident after the third mating, may be related to the requirement to replenish proteins to be transferred to the female. Conclusions/Significance We have developed the first large-scale dataset for novel studies on functions and processes associated with the reproductive biology of Ceratitis capitata. The identified genes may help study genome evolution, in light of the high adaptive potential of the medfly. In addition, studies of male recovery dynamics in terms

  10. Gene expression divergence and nucleotide differentiation between males of different color morphs and mating strategies in the ruff

    PubMed Central

    Ekblom, Robert; Farrell, Lindsay L; Lank, David B; Burke, Terry

    2012-01-01

    By next generation transcriptome sequencing, it is possible to obtain data on both nucleotide sequence variation and gene expression. We have used this approach (RNA-Seq) to investigate the genetic basis for differences in plumage coloration and mating strategies in a non-model bird species, the ruff (Philomachus pugnax). Ruff males show enormous variation in the coloration of ornamental feathers, used for individual recognition. This polymorphism is linked to reproductive strategies, with dark males (Independents) defending territories on leks against other Independents, whereas white morphs (Satellites) co-occupy Independent's courts without agonistic interactions. Previous work found a strong genetic component for mating strategy, but the genes involved were not identified. We present feather transcriptome data of more than 6,000 de-novo sequenced ruff genes (although with limited coverage for many of them). None of the identified genes showed significant expression divergence between males, but many genetic markers showed nucleotide differentiation between different color morphs and mating strategies. These include several feather keratin genes, splicing factors, and the Xg blood-group gene. Many of the genes with significant genetic structure between mating strategies have not yet been annotated and their functions remain to be elucidated. We also conducted in-depth investigations of 28 pre-identified coloration candidate genes. Two of these (EDNRB and TYR) were specifically expressed in black- and rust-colored males, respectively. We have demonstrated the utility of next generation transcriptome sequencing for identifying and genotyping large number of genetic markers in a non-model species without previous genomic resources, and highlight the potential of this approach for addressing the genetic basis of ecologically important variation. PMID:23145334

  11. Failure of glucocorticoid feedback in males of a population of small marsupials (Antechinus swainsonii) during the period of mating.

    PubMed

    McDonald, I R; Lee, A K; Than, K A; Martin, R W

    1986-01-01

    In an investigation of the factors leading to the increase in the concentration of plasma free glucocorticoid, which results in immunosuppression and death after mating of all males in natural populations of a small shrew-like marsupial, the dusky antechinus (Antechinus swainsonii), the integrity of the glucocorticoid feedback control of the concentration of plasma cortisol was examined by use of dexamethasone-suppression tests. Injection of 0.2 mg dexamethasone/kg i.m. caused a marked fall in the concentration of plasma cortisol 17 h later, approximately 2 months and 2 weeks before the annual mating period in mid-July. However, the same dose had no significant effect on the increased concentration of plasma cortisol characteristic of the mid- to late July mating period. Injection of 100 i.u. ACTH/kg i.m. caused a significant increase in the concentration of plasma cortisol 6-7 h later on all occasions, indicating that the responsiveness of the adrenal cortex to ACTH did not change. Pretreatment with dexamethasone had no effect on the ACTH-stimulated cortisol concentration, ruling out a possible direct effect of dexamethasone on adrenocortical secretion in this species. Dexamethasone also reduced the concentration of plasma testosterone when the level was low, before the mating period, but not when the level was high, at the beginning of the mating period. It is concluded that, in association with a rapid increase in the concentration of plasma testosterone, an increase in aggression and intense mating activity, glucocorticoid feedback control of ACTH secretion is impaired.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Characterizing and marker-assisting a novel chili pepper (Capsicum annuum L.) yellow bud mutant with cytoplasmic male sterility.

    PubMed

    Sun, G S; Dai, Z L; Bosland, P W; Wang, Q; Sun, C Q; Zhang, Z C; Ma, Z H

    2017-02-23

    Cytoplasmic male sterility (CMS) in pepper is a better way to produce hybrid seeds compared to manual production. We used the two sequence characterized amplified region (SCAR) markers (CRF-SCAR and CMS-SCAR130) in CMS pepper, to identify the genotype. We assembled two CMS yellow bud mutants (YBM; YBM12-A and YBM12-B). This mutation in leaf color is controlled by a single dominant nuclear gene. The aim was to create a new hybrid seed production method that reduces the costs and increases F1 hybrid seed purity. The results suggest that the CRF-SCAR and CMS-SCAR130 markers can be used together in multiple generations to screen for restorer or maintainer genes. We found the marker linked to the restorer gene (Rf) in the C-line and F1 hybrids, as well as partially in the F2 generation, whereas it was not found in the sterile YBM12-A or the maintainer line YBM12-B. In the F2 population, sterility and fertility segregated at a 3:1 ratio based on the CRF-SCAR marker. A 130 bp fragment was produced in the YBM12-A, F1, and F2 populations, suggesting that these lines contained sterile cytoplasm. A 140 bp fragment present in the YBM12-B and C-line indicated that these lines contained normal cytoplasm. In addition, we identified some morphological characters distinguishing sterile and fertile buds and flowers that may be linked to the sterility gene. If more restorer lines are identified, CMS expressing the YBM trait can be used in hybrid seed production.

  13. Cytoplasmic Male Sterility-Associated Chimeric Open Reading Frames Identified by Mitochondrial Genome Sequencing of Four Cajanus Genotypes

    PubMed Central

    Tuteja, Reetu; Saxena, Rachit K.; Davila, Jaime; Shah, Trushar; Chen, Wenbin; Xiao, Yong-Li; Fan, Guangyi; Saxena, K. B.; Alverson, Andrew J.; Spillane, Charles; Town, Christopher; Varshney, Rajeev K.

    2013-01-01

    The hybrid pigeonpea (Cajanus cajan) breeding technology based on cytoplasmic male sterility (CMS) is currently unique among legumes and displays major potential for yield increase. CMS is defined as a condition in which a plant is unable to produce functional pollen grains. The novel chimeric open reading frames (ORFs) produced as a results of mitochondrial genome rearrangements are considered to be the main cause of CMS. To identify these CMS-related ORFs in pigeonpea, we sequenced the mitochondrial genomes of three C. cajan lines (the male-sterile line ICPA 2039, the maintainer line ICPB 2039, and the hybrid line ICPH 2433) and of the wild relative (Cajanus cajanifolius ICPW 29). A single, circular-mapping molecule of length 545.7 kb was assembled and annotated for the ICPA 2039 line. Sequence annotation predicted 51 genes, including 34 protein-coding and 17 RNA genes. Comparison of the mitochondrial genomes from different Cajanus genotypes identified 31 ORFs, which differ between lines within which CMS is present or absent. Among these chimeric ORFs, 13 were identified by comparison of the related male-sterile and maintainer lines. These ORFs display features that are known to trigger CMS in other plant species and to represent the most promising candidates for CMS-related mitochondrial rearrangements in pigeonpea. PMID:23792890

  14. Reversible male sterility in eggplant (Solanum melongena L.) by artificial microRNA-mediated silencing of general transcription factor genes.

    PubMed

    Toppino, Laura; Kooiker, Maarten; Lindner, Matias; Dreni, Ludovico; Rotino, Giuseppe L; Kater, Martin M

    2011-08-01

    Since decades, plant male sterility is considered a powerful tool for biological containment to minimize unwanted self-pollination for hybrid seed production. Furthermore, prevention of pollen dispersal also answers to concerns regarding transgene flow via pollen from Genetically Modified (GM) crops to traditional crop fields or wild relatives. We induced male sterility by suppressing endogenous general transcription factor genes, TAFs, using anther-specific promoters combined with artificial microRNA (amiRNA) technology (Schwab et al., 2006). The system was made reversible by the ethanol inducible expression of an amiRNA-insensitive form of the target gene. We provide proof of concept in eggplant, a cultivated crop belonging to the Solanaceae family that includes many important food crops. The transgenic eggplants that we generated are completely male sterile and fertility can be fully restored by short treatments with ethanol, confirming the efficiency but also the reliability of the system in view of open field cultivation. By combining this system with induced parthenocarpy (Rotino et al., 1997), we provide a novel example of complete transgene containment in eggplant, which enables biological mitigation measures for the benefit of coexistence or biosafety purposes for GM crop cultivation.

  15. The influence of territoriality and mating system on the evolution of male care: a phylogenetic study on fish.

    PubMed

    Ah-King, M; Kvarnemo, C; Tullberg, B S

    2005-03-01

    Evolution of male care is still poorly understood. Using phylogenetically matched-pairs comparisons we tested for effects of territoriality and mating system on male care evolution in fish. All origins of male care were found in pair-spawning species (with or without additional males such as sneakers) and none were found in group-spawning species. However, excluding group spawners, male care originated equally often in pair-spawning species with additional males as in strict pair-spawning species. Evolution of male care was also significantly related to territoriality. Yet, most pair-spawning taxa with male care are also territorial, making their relative influence difficult to separate. Furthermore, territoriality also occurs in group-spawning species. Hence, territoriality is not sufficient for male care to evolve. Rather, we argue that it is the combination of territoriality and pair spawning with sequential polygyny that favours the evolution of male care, and we discuss our results in relation to paternity assurance and sexual selection.

  16. Indirect fitness consequences of mate choice in sticklebacks: offspring of brighter males grow slowly but resist parasitic infections.

    PubMed Central

    Barber, I; Arnott, S A; Braithwaite, V A; Andrew, J; Huntingford, F A

    2001-01-01

    'Good genes' models of sexual selection suggest that elaborate male sexual ornaments have evolved as reliable signals of male quality because only males of high genetic viability are able to develop and maintain them. Females benefit from choosing such individuals if quality is heritable. A key prediction is that the offspring of males with elaborate mating displays will perform better than those of less elaborate males, but it has proved difficult to demonstrate such an effect independently of the effects of differences in parental investment. We tested for 'good genes' linked to male ornamentation in the three-spined stickleback Gasterosteus aculeatus using in vitro fertilization to generate maternal half-siblings, which were raised without parental care. Maternal half-siblings sired by brightly coloured males grew less quickly than half-siblings sired by dull males but were more resistant to a controlled disease challenge. Among the offspring that became infected, those with brighter fathers had higher white blood cell counts. This suggests that highly ornamented males confer disease resistance on their offspring. The association with reduced growth suggests a mechanism for the maintenance of heritable variation in both disease resistance and male sexual coloration. PMID:12123300

  17. Coevolutionary Feedbacks between Female Mating Interval and Male Allocation to Competing Sperm Traits Can Drive Evolution of Costly Polyandry.

    PubMed

    Bocedi, Greta; Reid, Jane M

    2016-03-01

    Complex coevolutionary feedbacks between female mating interval and male sperm traits have been hypothesized to explain the evolution and persistence of costly polyandry. Such feedbacks could potentially arise because polyandry creates sperm competition and consequent selection on male allocation to sperm traits, while the emerging sperm traits could create female sperm limitation and, hence, impose selection for increased polyandry. However, the hypothesis that costly polyandry could coevolve with male sperm dynamics has not been tested. We built a genetically explicit individual-based model to simulate simultaneous evolution of female mating interval and male allocation to sperm number versus longevity, where these two sperm traits trade off. We show that evolution of competing sperm traits under polyandry can indeed cause female sperm limitation and, hence, promote further evolution and persistence of costly polyandry, particularly when sperm are costly relative to the degree of female sperm limitation. These feedbacks were stronger, and greater polyandry evolved, when postcopulatory competition for paternity followed a loaded rather than fair raffle and when sperm traits had realistically low heritability. We therefore demonstrate that the evolution of allocation to sperm traits driven by sperm competition can prevent males from overcoming female sperm limitation, thereby driving ongoing evolution of costly polyandry.

  18. Female preference for multi-modal courtship: multiple signals are important for male mating success in peacock spiders

    PubMed Central

    Girard, Madeline B.; Elias, Damian O.; Kasumovic, Michael M.

    2015-01-01

    A long-standing goal for biologists has been to understand how female preferences operate in systems where males have evolved numerous sexually selected traits. Jumping spiders of the Maratus genus are exceptionally sexually dimorphic in appearance and signalling behaviour. Presumably, strong sexual selection by females has played an important role in the evolution of complex signals displayed by males of this group; however, this has not yet been demonstrated. In fact, despite apparent widespread examples of sexual selection in nature, empirical evidence is relatively sparse, especially for species employing multiple modalities for intersexual communication. In order to elucidate whether female preference can explain the evolution of multi-modal signalling traits, we ran a series of mating trials using Maratus volans. We used video recordings and laser vibrometry to characterize, quantify and examine which male courtship traits predict various metrics of mating success. We found evidence for strong sexual selection on males in this system, with success contingent upon a combination of visual and vibratory displays. Additionally, independently produced, yet correlated suites of multi-modal male signals are linked to other aspects of female peacock spider behaviour. Lastly, our data provide some support for both the redundant signal and multiple messages hypotheses for the evolution of multi-modal signalling. PMID:26631566

  19. A modulatory effect of male voice pitch on long-term memory in women: evidence of adaptation for mate choice?

    PubMed

    Smith, David S; Jones, Benedict C; Feinberg, David R; Allan, Kevin

    2012-01-01

    From a functionalist perspective, human memory should be attuned to information of adaptive value for one's survival and reproductive fitness. While evidence of sensitivity to survival-related information is growing, specific links between memory and information that could impact upon reproductive fitness have remained elusive. Here, in two experiments, we showed that memory in women is sensitive to male voice pitch, a sexually dimorphic cue important for mate choice because it not only serves as an indicator of genetic quality, but may also signal behavioural traits undesirable in a long-term partner. In Experiment 1, we report that women's visual object memory is significantly enhanced when an object's name is spoken during encoding in a masculinised (i.e., lower-pitch) versus feminised (i.e., higher-pitch) male voice, but that no analogous effect occurs when women listen to other women's voices. Experiment 2 replicated this pattern of results, additionally showing that lowering and raising male voice pitch enhanced and impaired women's memory, respectively, relative to a baseline (i.e., unmanipulated) voice condition. The modulatory effect of sexual dimorphism cues in the male voice may reveal a mate-choice adaptation within women's memory, sculpted by evolution in response to the dilemma posed by the double-edged qualities of male masculinity.

  20. Male genital size reflects a tradeoff between attracting mates and avoiding predators in two live-bearing fish species

    PubMed Central

    Langerhans, R. Brian; Layman, Craig A.; DeWitt, Thomas J.

    2005-01-01

    Male genitalia may experience more rapid, divergent evolution than any other animal character, but why? Research during the past several decades has culminated in the view that genital diversification primarily results from postmating sexual selection (e.g., sperm competition or cryptic female choice). However, the potential roles of premating sexual selection (e.g., mate choice) and natural selection have received little attention. We examined the possible importance of these mechanisms by investigating divergence in male genitalia among populations differing in predator regime for two species of live-bearing fish (Gambusia affinis in Texas and Gambusia hubbsi in The Bahamas). When controlled for body size, males exhibited a larger gonopodium (sperm-transfer organ) in predator-free environments than in predatory environments, a trend that persisted across space (multiple populations), time (multiple years), and species. By conducting laboratory experiments with G. affinis, we found that premating sexual selection seems to favor larger male genitalia (females exhibited mating preference for males having larger gonopodia), but natural selection in the presence of predatory fishes seems to favor reduced genital size (larger gonopodium size was associated with reduced burst-swimming performance, an important antipredator behavior). Although postmating sexual selection is widely presumed to be the most important mechanism driving genital diversification, these findings suggest that alternative mechanisms, particularly for organisms that cannot retract their genitalia, may also prove important. PMID:15894618

  1. The effect of aqueous extract of gross and commercial yerba mate (Ilex paraguariensis) on intra-abdominal and epididymal fat and glucose levels in male Wistar rats.

    PubMed

    Silva, Raquel D'Agostini; Bueno, Audrin Loss Scopel; Gallon, Carin Weirich; Gomes, Luana Ferreira; Kaiser, Samuel; Pavei, Cabral; Ortega, George González; Kucharski, Luiz Carlos; Jahn, Matheus Parmegiani

    2011-09-01

    This study analyzed the plasma lipid profile, glucose levels and fat deposits in male rats treated with aqueous extract of gross yerba mate, commercial yerba mate or water. Yerba mate treatment did not change body weight gain and lipid profile. The consumption of gross yerba mate significantly increased blood glucose (6.6 mmol/L) as compared to the water (4.8 mmol/L) and commercial group (5.2 mmol/L) and decreased epididymal and intra-abdominal deposits (10.1mg/g and 23.7 mg/g of weight) as compared to the water (15.4 mg/g and 36.9 mg/g of weight) and commercial group (12.5mg/g and 28 mg/g of weight). The results suggest that gross yerba mate reduces fat more efficiently but produces a greater increase in blood glucose when compared to commercial yerba mate and water groups.

  2. Organelle Simple Sequence Repeat Markers Help to Distinguish Carpelloid Stamen and Normal Cytoplasmic Male Sterile Sources in Broccoli

    PubMed Central

    Shu, Jinshuai; Liu, Yumei; Li, Zhansheng; Zhang, Lili; Fang, Zhiyuan; Yang, Limei; Zhuang, Mu; Zhang, Yangyong; Lv, Honghao

    2015-01-01

    We previously discovered carpelloid stamens when breeding cytoplasmic male sterile lines in broccoli (Brassica oleracea var. italica). In this study, hybrids and multiple backcrosses were produced from different cytoplasmic male sterile carpelloid stamen sources and maintainer lines. Carpelloid stamens caused dysplasia of the flower structure and led to hooked or coiled siliques with poor seed setting, which were inherited in a maternal fashion. Using four distinct carpelloid stamens and twelve distinct normal stamens from cytoplasmic male sterile sources and one maintainer, we used 21 mitochondrial simple sequence repeat (mtSSR) primers and 32 chloroplast SSR primers to identify a mitochondrial marker, mtSSR2, that can differentiate between the cytoplasm of carpelloid and normal stamens. Thereafter, mtSSR2 was used to identify another 34 broccoli accessions, with an accuracy rate of 100%. Analysis of the polymorphic sequences revealed that the mtSSR2 open reading frame of carpelloid stamen sterile sources had a deletion of 51 bases (encoding 18 amino acids) compared with normal stamen materials. The open reading frame is located in the coding region of orf125 and orf108 of the mitochondrial genomes in Brassica crops and had the highest similarity with Raphanus sativus and Brassica carinata. The current study has not only identified a useful molecular marker to detect the cytoplasm of carpelloid stamens during broccoli breeding, but it also provides evidence that the mitochondrial genome is maternally inherited and provides a basis for studying the effect of the cytoplasm on flower organ development in plants. PMID:26407159

  3. The health of a nation predicts their mate preferences: cross-cultural variation in women's preferences for masculinized male faces.

    PubMed

    DeBruine, Lisa M; Jones, Benedict C; Crawford, John R; Welling, Lisa L M; Little, Anthony C

    2010-08-07

    Recent formulations of sexual selection theory emphasize how mate choice can be affected by environmental factors, such as predation risk and resource quality. Women vary greatly in the extent to which they prefer male masculinity and this variation is hypothesized to reflect differences in how women resolve the trade-off between the costs (e.g. low investment) and benefits (e.g. healthy offspring) associated with choosing a masculine partner. A strong prediction of this trade-off theory is that women's masculinity preferences will be stronger in cultures where poor health is particularly harmful to survival. We investigated the relationship between women's preferences for male facial masculinity and a health index derived from World Health Organization statistics for mortality rates, life expectancies and the impact of communicable disease. Across 30 countries, masculinity preference increased as health decreased. This relationship was independent of cross-cultural differences in wealth or women's mating strategies. These findings show non-arbitrary cross-cultural differences in facial attractiveness judgements and demonstrate the use of trade-off theory for investigating cross-cultural variation in women's mate preferences.

  4. Embryonic pathogenesis of hypogonadism and renal hypoplasia in hgn/hgn rats characterized by male sterility, reduced female fertility and progressive renal insufficiency.

    PubMed

    Suzuki, Hiroetsu; Yagi, Mio; Saito, Kenichi; Suzuki, Katsushi

    2007-03-01

    Congenital hypoplasia and dysplasia affect the postnatal development of organs, their physiological functioning in adulthood and the incidence of related diseases at an advanced age. Hypogonadic (hgn/hgn) rats are characterized by male sterility, reduced female fertility, progressive renal insufficiency and growth retardation, all controlled by a single recessive allele (hgn) located on chromosome 10. Since our previous studies indicated that the hypoplasia (dysplasia) of the affected organs was present at birth, we examined the embryonic pathogenesis. We mated hgn/hgn females to Brown Norway males and backcrossed F(1) males to hgn/hgn females. The resulting N(1) fetuses were genotyped using a hgn-linked microsatellite. Both sexes of hgn/hgn fetuses showed low body weight after embryonic day (ED) 15.5 and renal hypoplasia after ED 17.5. Their kidneys contained a reduced number of nephrons in a poorly formed nephrogenic zone and renal cortex. The hgn/hgn ovaries contained a small number of oogonia at ED 15.5 and oocytes after ED 17.5. Testicular growth defects were obvious after ED 17.5, and reduced numbers of Sertoli cells were detected at ED 19.5 and 21.5. The seminiferous cords in hgn/hgn testes contained more apoptotic and mitotic cells than those in +/hgn testes. These findings suggest that the phenotypes described in adult hgn/hgn rats result from embryonic hypogenesis, which continues to early postnatal stage and causes a reduction in functional tissues and cells. Since hgn/hgn rats have an insertion mutation in the microtubule-associated protein Spag5 gene, the embryonic hypogenesis described in hgn/hgn rats might result from defective cell proliferation.

  5. Males and females contribute unequally to offspring genetic diversity in the polygynandrous mating system of wild boar.

    PubMed

    Pérez-González, Javier; Costa, Vânia; Santos, Pedro; Slate, Jon; Carranza, Juan; Fernández-Llario, Pedro; Zsolnai, Attila; Monteiro, Nuno M; Anton, István; Buzgó, József; Varga, Gyula; Beja-Pereira, Albano

    2014-01-01

    The maintenance of genetic diversity across generations depends on both the number of reproducing males and females. Variance in reproductive success, multiple paternity and litter size can all affect the relative contributions of male and female parents to genetic variation of progeny. The mating system of the wild boar (Sus scrofa) has been described as polygynous, although evidence of multiple paternity in litters has been found. Using 14 microsatellite markers, we evaluated the contribution of males and females to genetic variation in the next generation in independent wild boar populations from the Iberian Peninsula and Hungary. Genetic contributions of males and females were obtained by distinguishing the paternal and maternal genetic component inherited by the progeny. We found that the paternally inherited genetic component of progeny was more diverse than the maternally inherited component. Simulations showed that this finding might be due to a sampling bias. However, after controlling for the bias by fitting both the genetic diversity in the adult population and the number of reproductive individuals in the models, paternally inherited genotypes remained more diverse than those inherited maternally. Our results suggest new insights into how promiscuous mating systems can help maintain genetic variation.

  6. Males and Females Contribute Unequally to Offspring Genetic Diversity in the Polygynandrous Mating System of Wild Boar

    PubMed Central

    Pérez-González, Javier; Costa, Vânia; Santos, Pedro; Slate, Jon; Carranza, Juan; Fernández-Llario, Pedro; Zsolnai, Attila; Monteiro, Nuno M.; Anton, István; Buzgó, József; Varga, Gyula; Beja-Pereira, Albano

    2014-01-01

    The maintenance of genetic diversity across generations depends on both the number of reproducing males and females. Variance in reproductive success, multiple paternity and litter size can all affect the relative contributions of male and female parents to genetic variation of progeny. The mating system of the wild boar (Sus scrofa) has been described as polygynous, although evidence of multiple paternity in litters has been found. Using 14 microsatellite markers, we evaluated the contribution of males and females to genetic variation in the next generation in independent wild boar populations from the Iberian Peninsula and Hungary. Genetic contributions of males and females were obtained by distinguishing the paternal and maternal genetic component inherited by the progeny. We found that the paternally inherited genetic component of progeny was more diverse than the maternally inherited component. Simulations showed that this finding might be due to a sampling bias. However, after controlling for the bias by fitting both the genetic diversity in the adult population and the number of reproductive individuals in the models, paternally inherited genotypes remained more diverse than those inherited maternally. Our results suggest new insights into how promiscuous mating systems can help maintain genetic variation. PMID:25541986

  7. It takes two to tango: reproductive skew and social correlates of male mating success in a lek-breeding bird

    PubMed Central

    Ryder, Thomas B.; Parker, Patricia G.; Blake, John G.; Loiselle, Bette A.

    2009-01-01

    Variance in reproductive success among individuals is a defining characteristic of many social vertebrates. Yet, our understanding of which male attributes contribute to reproductive success is still fragmentary in most cases. Male–male reproductive coalitions, where males jointly display to attract females, are of particular interest to evolutionary biologists because one male appears to forego reproduction to assist the social partner. By examining the relationship between social behaviour and reproductive success, we can elucidate the proximate function of coalitions in the context of mate choice. Here, we use data from a 4-year study of wire-tailed manakins (Pipra filicauda) to provide molecular estimates of reproductive skew and to test the hypothesis that male–male social interactions, in the context of coordinated displays, positively influence a male's reproductive success. More specifically, we quantify male–male social interactions using network metrics and predict that greater connectivity will result in higher relative reproductive success. Our data show that four out of six leks studied had significant reproductive skew, with success apportioned to very few individuals in each lek. Metrics of male social affiliations derived from our network analysis, especially male connectivity, measured as the number of males with whom the focal male has extended interactions, were strong predictors of the number of offspring sired. Thus, network connectivity is associated with male fitness in wire-tailed manakins. This pattern may be the result of shared cues used by both sexes to assess male quality, or the result of strict female choice for coordinated display behaviour. PMID:19324732

  8. Copulation is reactivated by bromocriptine in male rats after reaching sexual satiety with a same sexual mate.

    PubMed

    Rojas-Hernández, Jorge; Juárez, Jorge

    2015-11-01

    Male sexual satiety has been associated with a decrease in dopamine levels. Spontaneous recovery of copulatory behavior begins at least 72 h after sexual satiety is reached or in the condition in which a sexually-satiated male is exposed to a new receptive female distinct from the one with which sexual satiety was reached. The aim of the present study was to explore whether dopaminergic activation by bromocriptine (BrCr) can reactivate copulatory behavior with the same sexual mate immediately after sexual satiety is reached. Male rats were divided into three groups exposed to one of the following three conditions: 1) administration of 2 mg/kgs.c. of BrCr and exposure to the same female with whom sexual satiety was previously reached; 2) administration of 0.3 mLs.c. of the vehicle solution with exposure to the same female with whom sexual satiety was reached; and, 3) exposure to a new receptive female after sexual satiety was reached. Results showed that BrCr significantly reactivated copulatory capability in sexually-satiated males with the same receptive female. In contrast, no males in the vehicle group ejaculated with the same female after reaching sexual exhaustion. Copulation was reactivated by BrCr in a way similar to that observed in untreated males exposed to a new receptive female (i.e., the Coolidge effect). The reversal of sexual satiety in the males treated with BrCr could be explained by its action on D2 family receptors, which promotes a reactivation of sexual motivation at a level sufficient to allow renewed copulation with the same female mate.

  9. Urinary C-peptide levels in male bonobos (Pan paniscus) are related to party size and rank but not to mate competition.

    PubMed

    Surbeck, Martin; Deschner, Tobias; Behringer, Verena; Hohmann, Gottfried

    2015-05-01

    Within- and between-species variation in male mating strategies has been attributed to a multitude of factors including male competitive ability and the distribution of fertile females across space and time. Differences in energy balance across and within males allow for the identification of some of the trade-offs associated with certain social and mating strategies. Bonobos live in groups with a high degree of fission-fusion dynamics, there is co-dominance between the sexes and a linear dominance hierarchy among males. Males compete over access to females, breeding is aseasonal, and females exhibit sexual swellings over extended time periods. In this study we use urinary C-peptide (UCP) levels in male bonobos (Pan paniscus) obtained from 260 urine samples from a wild bonobo community, to quantify male energy balance during mate competition and levels of gregariousness in the species. Although high ranking males are more aggressive, spend more time in proximity to maximally tumescent females, and have higher mating frequencies, we found no indication that mate guarding or mate competition affected male energy balance. Our results showed a positive correlation between monthly mean UCP levels and mean party size. When traveling in large parties, high ranking males had higher UCP levels than those of the low ranking males. These results support the hypothesis that patterns of fission-fusion dynamics in bonobos are either linked to energy availability in the environment or to the energetic costs of foraging. The finding of a rank-bias in UCP levels in larger parties could also reflect an increase in contest competition among males over access to food.

  10. [Cloning and expression of atp6 and atp9 genes from ramie (Boehmeria nivea (L.) Gaud.) and their relationship with cytoplasmic male sterility].

    PubMed

    Duan, Ji-Qiang; DU, Guang-Hui; Li, Jian-Yong; Liang, Xue-Ni; Liu, Fei-Hu

    2008-11-01

    The atp6 and apt9 gene fragments associated with cytoplasmic male sterility (CMS) were cloned from the mitochondrial DNA of a ramie (Boehmeria nivea (L.) Gaud.) cytoplasmic male sterile line and its maintainer and restorer lines using PCR and degenerated primer strategy. The primers were designed according to the reserved sequences in the encoding region of mitochondrial genes atp6 and atp9 of some dicotyledons from GenBank. These fragments did not have complete encoding region but showed the homology of 94% and 85% with atp6 and atp9 genes from the referred dicotyledons in GenBank. The complete atp6 and atp9 genes including the complete open reading frames were cloned by means of amplifying the 3' and 5'end unknown sequences of these gene fragments using DNA Walking method. The atp6 gene showed no difference among ramie male sterile line, maintainer and restorer lines at mtDNA sequence, transcription and translation control and protein level. However, compared to the maintainer and restorer lines, the atp9 gene of the male sterile line was different and deletion in several bases at the 3' end of the encoding region. An abnormally high expression of atp9 gene in the male sterile line at the budding stage and full-bloom stage was analyzed by RT-PCR analysis. These results indicated that the variation in DNA sequence and/or abnormality in expression of atp9 gene in the male sterile line maybe closely related to ramie CMS.

  11. Sterile 'Judas' carp--Surgical sterilisation does not impair growth, endocrine and behavioural responses of male carp.

    PubMed

    Patil, Jawahar G; Purser, G J; Nicholson, A M

    2015-09-15

    Use of 'Judas' fish to betray the locations of conspecifics is a powerful tool in management of invasive pest fish but poses a risk of contributing to recruitment. Our aim therefore was to generate surgically sterilised male common carp (Cyprinus carpio) and test whether they readily assimilate into wild populations, retain sexual behaviour and successfully betray the locations of feral carp. Male common carp were surgically sterilised (n=44) adopting a two-point nip technique, using either a haemoclip, suture or electro cautery to tie each of the testicular ducts about 2.5 cm cranial to urogenital sinus-retaining all of the glandular testis tissue. Observed survival (95%) and success (>70%) rates were relatively high. Plasma steroids (11-keto testosterone and 17β-estradiol) were quantified by immunoassay. A subset of sterile and control male fish (n=7 each) were implanted with radio-transmitters and released into Lake Sorell (50 km(2)) and their ability to betray the location of feral carp was assessed by radio tracking and targeted fishing. There was a statistically significant difference in 11-keto testosterone and 17β-estradiol levels over time (P<0.05), but not between the sterile and control groups within each sampling time (P>0.05), implying that surgery did not compromise the animals physiologically. The sterile Judas fish integrated well into the population-behaving similarly to control Judas males and assisted in the capture of feral carp. The study marks a significant breakthrough in the management of this pest fish with potential adoption to the management of other pest fish globally.

  12. The reproductive biology of male cottonmouths (Agkistrodon piscivorus): do plasma steroid hormones predict the mating season?

    PubMed

    Graham, Sean P; Earley, Ryan L; Hoss, Shannon K; Schuett, Gordon W; Grober, Matthew S

    2008-01-01

    To better understand the proximate causation of the two major types of mating seasons described for North American pitvipers, we conducted a field study of the cottonmouth (Agkistrodon piscivorus) in Georgia from September 2003 to May 2005 that included an extensive observational regime and collection of tissues for behavioral, anatomical, histological, and hormone analysis. Enzyme immunoassays (EIA) of plasma samples and standard histological procedures were conducted on reproductive tissues. Evidence from the annual testosterone (T) and sexual segment of the kidney (SSK) cycle and their relationship to the spermatogenic cycle provide correlative evidence of a unimodal mating pattern in this species of pitviper, as these variables consistently predict the mating season in all snake species previously examined under natural conditions. In most reptiles studied to date, high plasma levels of T and corticosterone (CORT) coincide during the mating period, making the cottonmouth an exception to this trend; we suggest two possible explanations for increased CORT during spring (regulation of a spring basking period), and decreased CORT during summer (avoiding reproductive behavioral inhibition), in this species.

  13. Humor Ability Reveals Intelligence, Predicts Mating Success, and Is Higher in Males

    ERIC Educational Resources Information Center

    Greengross, Gil; Miller, Geoffrey

    2011-01-01

    A good sense of humor is sexually attractive, perhaps because it reveals intelligence, creativity, and other "good genes" or "good parent" traits. If so, intelligence should predict humor production ability, which in turn should predict mating success. In this study, 400 university students (200 men and 200 women) completed…

  14. Irradiation of adult Epiphyas postvittana (Lepidoptera: Tortricidae): egg sterility in parental and F1 generations.

    PubMed

    Jang, Eric B; McInnis, Donald O; Kurashima, Rick; Woods, Bill; Suckling, David M

    2012-02-01

    Adult Epiphyas postvittana Walker were irradiated using a Cobalt 60 source to determine the dose needed to achieve complete egg sterility of mated female moths, and egg sterility of female moths mated to F1 generation males. Adult male and female E. postvittana were irradiated at 100, 200, 250, and 300 Gy and their fertility (when crossed with normal moths) was compared with nonirradiated moths. Viable progeny (determined by egg hatch) were found at doses of 100 and 200 Gy, but very little at 250 and 300 Gy. In particular, there was no survival of female progeny into the F1 generation. Males irradiated at 250 and 300 Gy had very low egg eclosion rates (2.25 and 1.86% at 250 and 300 Gy, respectively) when mated with normal females. The F2 generation from those male progeny had a mean percent hatched of < 1.02%. Based on our results, a dose of 250-300 Gy is recommended for irradiation of E. postvittana adults used for sterile insect technique (SIT) if sterility of parental moths is the desired outcome. Our data also suggests that inclusion of F1 hybrid sterility rather than parental generation sterility into programs using the SIT may allow for doses lower than what we have reported, especially during initial phases of an eradication program where increase fitness of moths might be desirable. Further research is needed to verify the use of F1 hybrid sterility in light brown apple moth SIT programs.

  15. Transcriptomic Analysis of Differentially Expressed Genes during Flower Organ Development in Genetic Male Sterile and Male Fertile Tagetes erecta by Digital Gene-Expression Profiling.

    PubMed

    Ai, Ye; Zhang, Qinghua; Wang, Weining; Zhang, Chunling; Cao, Zhe; Bao, Manzhu; He, Yanhong

    2016-01-01

    Tagetes erecta is an important commercial plant of Asteraceae family. The male sterile (MS) and male fertile (MF) two-type lines of T. erecta have been utilized in F1 hybrid production for many years, but no report has been made to identify the genes that specify its male sterility that is caused by homeotic conversion of floral organs. In this study, transcriptome assembly and digital gene expression profiling were performed to generate expression profiles of MS and MF plants. A cDNA library was generated from an equal mixture of RNA isolated from MS and MF flower buds (1 mm and 4 mm in diameter). Totally, 87,473,431 clean tags were obtained and assembled into 128,937 transcripts among which 65,857 unigenes were identified with an average length of 1,188 bp. About 52% of unigenes (34,176) were annotated in Nr, Nt, Pfam, KOG/COG, Swiss-Prot, KO (KEGG Ortholog database) and/or GO. Taking the above transcriptome as reference, 125 differentially expressed genes were detected in both developmental stages of MS and MF flower buds. MADS-box genes were presumed to be highly related to male sterility in T. erecta based on histological and cytological observations. Twelve MADS-box genes showed significantly different expression levels in flower buds 4 mm in diameter, whereas only one gene expressed significantly different in flower buds 1 mm in diameter between MS and MF plants. This is the first transcriptome analysis in T. erecta and will provide a valuable resource for future genomic studies, especially in flower organ development and/or differentiation.

  16. Transcriptomic Analysis of Differentially Expressed Genes during Flower Organ Development in Genetic Male Sterile and Male Fertile Tagetes erecta by Digital Gene-Expression Profiling

    PubMed Central

    Ai, Ye; Zhang, Qinghua; Wang, Weining; Zhang, Chunling; Cao, Zhe; Bao, Manzhu; He, Yanhong

    2016-01-01

    Tagetes erecta is an important commercial plant of Asteraceae family. The male sterile (MS) and male fertile (MF) two-type lines of T. erecta have been utilized in F1 hybrid production for many years, but no report has been made to identify the genes that specify its male sterility that is caused by homeotic conversion of floral organs. In this study, transcriptome assembly and digital gene expression profiling were performed to generate expression profiles of MS and MF plants. A cDNA library was generated from an equal mixture of RNA isolated from MS and MF flower buds (1 mm and 4 mm in diameter). Totally, 87,473,431 clean tags were obtained and assembled into 128,937 transcripts among which 65,857 unigenes were identified with an average length of 1,188 bp. About 52% of unigenes (34,176) were annotated in Nr, Nt, Pfam, KOG/COG, Swiss-Prot, KO (KEGG Ortholog database) and/or GO. Taking the above transcriptome as reference, 125 differentially expressed genes were detected in both developmental stages of MS and MF flower buds. MADS-box genes were presumed to be highly related to male sterility in T. erecta based on histological and cytological observations. Twelve MADS-box genes showed significantly different expression levels in flower buds 4 mm in diameter, whereas only one gene expressed significantly different in flower buds 1 mm in diameter between MS and MF plants. This is the first transcriptome analysis in T. erecta and will provide a valuable resource for future genomic studies, especially in flower organ development and/or differentiation. PMID:26939127

  17. Silencing of meiosis-critical genes for engineering male sterility in plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Engineering sterile traits in plants through the tissue-specific expression of a cytotoxic gene provides an effective way for containing transgene flow; however, the microbial origin of cytotoxic genes has raised concerns. In an attempt to develop a safe alternative, we have chosen the meiosis-crit...

  18. Turgid female toads give males the slip: a new mechanism of female mate choice in the Anura

    PubMed Central

    Bruning, Bas; Phillips, Benjamin L.; Shine, Richard

    2010-01-01

    In many anuran species, males vocalize to attract females but will grasp any female that comes within reach and retain their hold unless displaced by a rival male. Thus, female anurans may face strong selection to repel unwanted suitors, but no mechanism is known for doing so. We suggest that a defensive trait (the ability to inflate the body to ward off attack) has been co-opted for this role: by inflating their bodies, females are more difficult for males to grasp and hence, it is easier for another male to displace an already amplexed rival. Inflating a model female cane toad (Bufo marinus) strongly reduced a male's ability to maintain amplexus; and females who were experimentally prevented from inflating their bodies experienced no successful takeovers from rival males, in contrast to control females. Thus, the ability of a female cane toad to inflate her body may allow her to manipulate the outcome of male–male competition. This overlooked mechanism of anuran mate choice may reflect a common evolutionary pattern, whereby females co-opt defensive traits for use in sexual selection. PMID:20053661

  19. Sperm production and mating potential of males after a cold shock on pupae of the parasitoid wasp Dinarmus basalis (Hymenoptera: Pteromalidae).

    PubMed

    Lacoume, Sandrine; Bressac, Christophe; Chevrier, Claude

    2007-10-01

    For ectothermic species, temperature is a key environmental factor influencing several aspects of their physiology and ecology, acting particularly on reproduction. To measure the consequences of a severe thermal stress during development on male reproduction, a cold shock (1h at -18 degrees C) was tested on Dinarmus basalis pupae. D. basalis (Hymenoptera: Pteromalidae) is a parasitoid wasp in which sperm management in both male and female is of prime importance. After a cold shock, developmental success was reduced, with a quarter of cold-shocked males not emerging correctly. The stress effects were estimated at the level of sperm stock in seminal vesicles of males at different ages and on the ability of 2-day-old males to access females in single and multiple mating and in male-male competition. Cold-shocked males had a reduced sperm stock compared to control males and this difference persisted with age. The rate of sperm production was similar in both groups. The consequences of a cold shock on male reproductive ability were perceptible in multiple mating and male-male competition but not in single mating. Cold-shocked males were at a disadvantage, inseminating fewer females and copulating less frequently. Finally, male pupae of D. basalis were able to withstand severe temperature stresses and their reproductive functions were partially preserved.

  20. Cytological basis of sterility in male and female hybrids between sibling species of grey voles Microtus arvalis and M. levis

    PubMed Central

    Torgasheva, Anna A.; Borodin, Pavel M.

    2016-01-01

    To make insight into the cytological basis of reproductive isolation, we examined chromosome synapsis and recombination in sterile male and female hybrids between Microtus arvalis and M. levis. These sibling species differ by a series of chromosomal rearrangements (fusions, inversions, centromere shifts and heterochromatin insertions). We found that meiosis in male hybrids was arrested at leptotene with complete failure of chromosome pairing and DNA double-strand breaks repair. In the female hybrids meiosis proceeded to pachytene; however, the oocytes varied in the degree of pairing errors. Some of them demonstrated almost correct chromosome pairing, while most of them contained a varying number of univalents and multivalents with extensive regions of asynapsis and non-homologous synapsis. Variation between oocytes was probably caused by stochasticity in the ratio of homologous to non-homologous pairing initiations. We suggest that substantial chromosomal and genetic divergence between the parental species affects preliminary alignment of homologues, homology search and elimination of ectopic interhomologue interactions that are required for correct homologous pairing. Apparently, pairing failure in male and aberrant synapsis in female vole hybrids followed by meiotic silencing of unsynapsed chromatin cause apoptosis of gametocytes and sterility. PMID:27811955

  1. Determination of cytoplasmic male sterile factors in onion plants (Allium cepa L.) using PCR-RFLP and SNP markers.

    PubMed

    Cho, Kwang-Soo; Yang, Tae-Jin; Hong, Su-Young; Kwon, Young-Seok; Woo, Jong-Gyu; Park, Hyo-Guen

    2006-06-30

    We have developed a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) marker that can distinguish male-fertile (N) and male-sterile (S) cytoplasm in onions. The PCR-RFLP marker was located in a chloroplast psbA gene amplicon. Digesting the amplicons from different cytoplasm-containing varieties with the restriction enzyme MspI revealed that N-cytoplasm plants have a functional MspI site (CCGG), whereas the S-cytoplasm plants has a substitution in that site (CTGG), and thus no MspI target. The results obtained using this PCR-RFLP marker to distinguish between cytoplasmic male sterile factors in 35 onion varieties corresponded with those using a CMS-specific sequence-characterized amplified region (SCAR) marker. Moreover, the PCR-RFLP marker can identify N- ot S-cytoplasms in DNA sample mixtures in which they are in up to a 10-fold minority, indicating that use of the marker has high diagnostic precision. We also demonstrated the usefulness of the SNP detected in the psbA gene for high-throughput discrimination of CMS factors using Real-time PCR and a TaqMan probe assay.

  2. Negative effects of prolonged dietary restriction on male mating effort: nuptial gifts as honest indicators of long-term male condition

    PubMed Central

    Macedo-Rego, Renato C.; Costa-Schmidt, Luiz Ernesto; Santos, Eduardo S. A.; Machado, Glauco

    2016-01-01

    The handicap principle proposes that sexual signals must be costly to be honest. Honesty may be maintained by the costs paid by honest signallers or by the potential costs of cheating. In the latter, handicaps should emerge as a consequence of specific biological constraints, such as life-history trade-offs. Nuptial prey-giving arthropods are good systems to investigate the honesty of sexual signals taking into account trade-offs between self-maintenance and mating effort. We experimentally evaluated if prolonged food shortage during early adulthood imposes long-term negative effects on gift construction by males of the spider Paratrechalea ornata. We also evaluated whether a burst of food availability improved body condition of poorly fed males, increasing their frequency of gift construction. Poorly fed males hardly constructed gifts, even after a marked increase in feeding rate, which clearly improved their body condition. Moreover, initially poorly fed males that latter received high food intake constructed lighter gifts than continuously well fed males. The long-term effects of prolonged dietary restriction on male propensity to construct a gift and on the size of this gift may increase the honesty of this sexually selected signal. From the female’s perspective the offer of a gift may bring information on male quality. PMID:26908253

  3. Negative effects of prolonged dietary restriction on male mating effort: nuptial gifts as honest indicators of long-term male condition.

    PubMed

    Macedo-Rego, Renato C; Costa-Schmidt, Luiz Ernesto; Santos, Eduardo S A; Machado, Glauco

    2016-02-24

    The handicap principle proposes that sexual signals must be costly to be honest. Honesty may be maintained by the costs paid by honest signallers or by the potential costs of cheating. In the latter, handicaps should emerge as a consequence of specific biological constraints, such as life-history trade-offs. Nuptial prey-giving arthropods are good systems to investigate the honesty of sexual signals taking into account trade-offs between self-maintenance and mating effort. We experimentally evaluated if prolonged food shortage during early adulthood imposes long-term negative effects on gift construction by males of the spider Paratrechalea ornata. We also evaluated whether a burst of food availability improved body condition of poorly fed males, increasing their frequency of gift construction. Poorly fed males hardly constructed gifts, even after a marked increase in feeding rate, which clearly improved their body condition. Moreover, initially poorly fed males that latter received high food intake constructed lighter gifts than continuously well fed males. The long-term effects of prolonged dietary restriction on male propensity to construct a gift and on the size of this gift may increase the honesty of this sexually selected signal. From the female's perspective the offer of a gift may bring information on male quality.

  4. Cytological characterization of a thermo-sensitive cytoplasmic male-sterile wheat line having K-type cytoplasm of Aegilops kotschyi

    PubMed Central

    Meng, Liying; Liu, Zihan; Zhang, Lingli; Hu, Gan; Song, Xiyue

    2016-01-01

    Male sterility is an important tool for obtaining crop heterosis. A thermo-sensitive cytoplasmic male-sterile (TCMS) line was developed recently using a new method based on tiller regeneration. In the present study, we explored the critical growth stages required to maintain thermo-sensitive male sterility in TCMS lines and found that fertility is associated with abnormal tapetal and microspore development. We investigated the fertility and cytology of temperature-treated plant anthers at various developmental stages. TCMS line KTM3315A exhibited thermo-sensitive male sterility in Zadoks growth stages 41–49 and 58–59. Morphologically, the line exhibited thermo-sensitive male sterility at 3–9 days before heading and at 3–6 days before flowering, and it was partially restored in three locations during spring and summer. TCMS line KTM3315A plants exhibited premature tapetal programmed cell death (PCD) from the early uninucleate stage of microspore development until the tapetal cells degraded completely. Microspore development was then blocked and the pollen abortion type was stainable abortion. Thus, male fertility in the line KTM3315A is sensitive to temperature and premature tapetal PCD is the main cause of pollen abortion, where it determines the starting period and affects male fertility conversion in K-type TCMS lines at certain temperatures. PMID:28163591

  5. Cytological characterization of a thermo-sensitive cytoplasmic male-sterile wheat line having K-type cytoplasm of Aegilops kotschyi.

    PubMed

    Meng, Liying; Liu, Zihan; Zhang, Lingli; Hu, Gan; Song, Xiyue

    2016-12-01

    Male sterility is an important tool for obtaining crop heterosis. A thermo-sensitive cytoplasmic male-sterile (TCMS) line was developed recently using a new method based on tiller regeneration. In the present study, we explored the critical growth stages required to maintain thermo-sensitive male sterility in TCMS lines and found that fertility is associated with abnormal tapetal and microspore development. We investigated the fertility and cytology of temperature-treated plant anthers at various developmental stages. TCMS line KTM3315A exhibited thermo-sensitive male sterility in Zadoks growth stages 41-49 and 58-59. Morphologically, the line exhibited thermo-sensitive male sterility at 3-9 days before heading and at 3-6 days before flowering, and it was partially restored in three locations during spring and summer. TCMS line KTM3315A plants exhibited premature tapetal programmed cell death (PCD) from the early uninucleate stage of microspore development until the tapetal cells degraded completely. Microspore development was then blocked and the pollen abortion type was stainable abortion. Thus, male fertility in the line KTM3315A is sensitive to temperature and premature tapetal PCD is the main cause of pollen abortion, where it determines the starting period and affects male fertility conversion in K-type TCMS lines at certain temperatures.

  6. Sterile inflammation as a factor in human male infertility: Involvement of Toll like receptor 2, biglycan and peritubular cells

    PubMed Central

    Mayer, C.; Adam, M.; Glashauser, L.; Dietrich, K.; Schwarzer, J.U.; Köhn, F.-M.; Strauss, L.; Welter, H.; Poutanen, M.; Mayerhofer, A.

    2016-01-01

    Changes in the wall of seminiferous tubules in men with impaired spermatogenesis imply sterile inflammation of the testis. We tested the hypothesis that the cells forming the wall of seminiferous tubules, human testicular peritubular cells (HTPCs), orchestrate inflammatory events and that Toll like receptors (TLRs) and danger signals from the extracellular matrix (ECM) of this wall are involved. In cultured HTPCs we detected TLRs, including TLR2. A TLR-2 ligand (PAM) augmented interleukin 6 (IL-6), monocyte chemo-attractant protein-1 (MCP-1) and pentraxin 3 (PTX3) in HTPCs. The ECM-derived proteoglycan biglycan (BGN) is secreted by HTPCs and may be a TLR2-ligand at HTPCs. In support, recombinant human BGN increased PTX3, MCP-1 and IL-6 in HTPCs. Variable endogenous BGN levels in HTPCs derived from different men and differences in BGN levels in the tubular wall in infertile men were observed. In testes of a systemic mouse model for male infertility, testicular sterile inflammation and elevated estradiol (E2) levels, BGN was also elevated. Hence we studied the role of E2 in HTPCs and observed that E2 elevated the levels of BGN. The anti-estrogen ICI 182,780 blocked this action. We conclude that TLR2 and BGN contribute to sterile inflammation and infertility in man. PMID:27849015

  7. Clinical Evaluation of Non-surgical Sterilization of Male Cats with Single Intra-testicular Injection of Calcium Chloride

    PubMed Central

    2011-01-01

    Background Calcium chloride solution is an established injectable sterilant in dogs and other mammals. With cat populations a continuing problem, we sought to explore its first use in cats. Six cats per group were injected with 5%, 10% or 20% calcium chloride dihydrate in saline solution with lignocaine hydrochloride, a local anaesthetic. Results At the 60th day post-injection, cat testes were collected and showed complete testicular necrosis and replacement by fibrous tissue; very low sperm counts; and reduction of serum testosterone by at least 70% in 20% dose. Androgenic enzyme activities and their expressions were also reduced in all the treated groups along with intra-testicular testosterone concentration was also low. Increased testicular lipid peroxidation, with reduced antioxidants and mitochondrial membrane potential, were evident following calcium chloride treatments. However, there were no apparent changes in serum concentrations of cortisol, fasting blood sugar level, blood urea nitrogen, packed cell volume, or total serum protein following calcium chloride injection, suggesting that this method of sterilization is not associated with any general stress response. Conclusion Calcium chloride solution demonstrates potential for androgenesis-eliminating nonsurgical sterilization of male cats in addition to its proven efficacy in dogs and other mammals. PMID:21774835

  8. [Preliminary gene-mapping of photoperiod-temperature sensitive genic male sterility in wheat (Triticum aestivum L.)].

    PubMed

    Cao, Shuang-He; Guo, Xiao-Li; Liu, Dong-Cheng; Zhang, Xiang-Qi; Zhang, Ai-Min

    2004-03-01

    The photoperiod-temperature sensitive genic male sterile (PTSGMS) line in wheat is important for the utilization of heterosis. The wheat line, BAU3338, is an excellent PTSGMS material identified in the recent years. In this study, its PTSGMS genes were mapped using molecular markers, SSR and ISSR. The result of molecular analysis showed that the two PTSGMS loci were identified and designated as ptms1 and ptms2, respectively. In addition, the genetic effect analysis indicated that the locus effect of ptms1 was 2-3 times larger than that of ptms2.

  9. Effects of selected neuropeptides, mating status and castration on male reproductive tract movements and immunolocalization of neuropeptides in earwigs.

    PubMed

    Rankin, Susan M; TeBrugge, Victoria A; Murray, Jill A; Schuler, Ashley M; Tobe, Stephen S

    2009-01-01

    In earwigs, the male reproductive system is complex, comprising accessory glands and long dual intromittent organs for transfer of materials to the female and for removal of rival sperm. We investigated potential factors altering contractions of the male reproductive tracts in vitro. Tracts from 0-day (newly emerged) males displayed relatively little motility in vitro; however, those from 5-day (intermediate stage of sexual maturity) and 8-day (fully mature) males pulsed vigorously. Both 1 and 100 nM proctolin (RYLPT-OH) stimulated the rate of contraction of reproductive tracts from both 5-day and 8-day males. In contrast, 1 nM and 100 nM FGLa AST (cockroach allatostatin) did not affect pulsations. However, 10 microM FGLa AST decreased activity of reproductive tracts. Mating decreased motility of tracts from 5-day old males, but did not alter motility of tracts from 8-day old males. Castration of larvae significantly suppressed reproductive tract motility in subsequent 8-day old adults compared with those of intact or sham-operated adults. Castration also suppressed seminal vesicle size. Lastly, we assessed the presence and distribution of proctolin-like and allatostatin-like immunoreactivity in tissues. Immunoreactivity to FGLa AST and proctolin was widespread, occurring in the brain and ventral ganglia. Surprisingly, we did not detect immunoreactivity to either FGLa AST or proctolin within the reproductive system; however, proctolin immunoreactivity was evident in nerves extending from the terminal ganglion of 8-day, but not 0-day, males. Collectively, these experiments demonstrate that the male earwig reproductive system is an appropriate model for use in addressing sexual maturation and activities in male insects.

  10. Comparison of reproductive traits of regular and irradiated male desert locust Schistocerca gregaria (Orthoptera: Acrididae): Evidence of last-male sperm precedence

    PubMed Central

    Dushimirimana, Severin; Hance, Thierry; Damiens, David

    2012-01-01

    Summary The sterile insect technique (SIT) is increasingly used to control pest insect populations. The success of SIT control programs depends on the ability to release sterile males and on the capacity of sterile males to compete with wild males to inseminate wild females. In this study, we evaluated the mating performance of Schistocerca gregaria (Försk.) males irradiated with 4 Gray. We compared reproductive traits, such as duration of precopulation time, mating duration, quantity of sperm stored by females after copulation, number of females mated successively and postmating competition of irradiated males with non-irradiated males. Irradiated males were able to mate but the resulting number of offspring was dramatically reduced compared to the average number of offspring observed during a regular mating. During a single copulation, irradiated males transferred fewer sperm than regular males but, theoretically, this quantity is enough to fertilize all the eggs produced by a female during its reproductive life. Irradiated males also had the ability to remove sperm from a previous mating with unirraditated males. This new information on the mating strategies helps explain the post-copulation guarding behaviour of S. gregaria. PMID:23213413

  11. The Evolutionary Consequences of Disrupted Male Mating Signals: An Agent-Based Modelling Exploration of Endocrine Disrupting Chemicals in the Guppy

    PubMed Central

    Senior, Alistair McNair; Nakagawa, Shinichi; Grimm, Volker

    2014-01-01

    Females may select a mate based on signalling traits that are believed to accurately correlate with heritable aspects of male quality. Anthropogenic actions, in particular chemicals released into the environment, are now disrupting the accuracy of mating signals to convey information about male quality. The long-term prediction for disrupted mating signals is most commonly loss of female preference. Yet, this prediction has rarely been tested using quantitative models. We use agent-based models to explore the effects of rapid disruption of mating signals. In our model, a gene determines survival. Males signal their level of genetic quality via a signal trait, which females use to select a mate. We allowed this system of sexual selection to become established, before introducing a disruption between the male signal trait and quality, which was similar in nature to that induced by exogenous chemicals. Finally, we assessed the capacity of the system to recover from this disruption. We found that within a relatively short time frame, disruption of mating signals led to a lasting loss of female preference. Decreases in mean viability at the population-level were also observed, because sexual-selection acting against newly arising deleterious mutations was relaxed. The ability of the population to recover from disrupted mating signals was strongly influenced by the mechanisms that promoted or maintained genetic diversity in traits under sexual selection. Our simple model demonstrates that environmental perturbations to the accuracy of male mating signals can result in a long-term loss of female preference for those signals within a few generations. What is more, the loss of this preference can have knock-on consequences for mean population fitness. PMID:25047080

  12. The evolutionary consequences of disrupted male mating signals: an agent-based modelling exploration of endocrine disrupting chemicals in the guppy.

    PubMed

    Senior, Alistair McNair; Nakagawa, Shinichi; Grimm, Volker

    2014-01-01

    Females may select a mate based on signalling traits that are believed to accurately correlate with heritable aspects of male quality. Anthropogenic actions, in particular chemicals released into the environment, are now disrupting the accuracy of mating signals to convey information about male quality. The long-term prediction for disrupted mating signals is most commonly loss of female preference. Yet, this prediction has rarely been tested using quantitative models. We use agent-based models to explore the effects of rapid disruption of mating signals. In our model, a gene determines survival. Males signal their level of genetic quality via a signal trait, which females use to select a mate. We allowed this system of sexual selection to become established, before introducing a disruption between the male signal trait and quality, which was similar in nature to that induced by exogenous chemicals. Finally, we assessed the capacity of the system to recover from this disruption. We found that within a relatively short time frame, disruption of mating signals led to a lasting loss of female preference. Decreases in mean viability at the population-level were also observed, because sexual-selection acting against newly arising deleterious mutations was relaxed. The ability of the population to recover from disrupted mating signals was strongly influenced by the mechanisms that promoted or maintained genetic diversity in traits under sexual selection. Our simple model demonstrates that environmental perturbations to the accuracy of male mating signals can result in a long-term loss of female preference for those signals within a few generations. What is more, the loss of this preference can have knock-on consequences for mean population fitness.

  13. Production of heritable partial sterility in the mouse by methyl methanesulphonate

    PubMed Central

    Jackson, H.; Partington, M.; Walpole, A. L.

    1964-01-01

    Partial sterility, in the sense of reduced reproductive capacity, has been demonstrated in the F1 progeny of male mice mated in the second week after a single dose of methyl methanesulphonate (50 mg/kg, intraperitoneally) with females of proved fertility. Sterility, both partial and complete, was encountered in the F2 generation obtained by mating F1 males and females with fertile partners. These results show that the compound, in a substerilizing dose, is capable of producing transmissible genetic damage. It is suggested that the procedure used is a practicable method of testing drugs for possible genetic effects. PMID:14256811

  14. The effects of diet, mating duration , female to male ratios and temperature on ovary activation, mating success and fecundity of Aethina tumida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of natural diet, mating and temperature on the ovary activation and fecundity of small hive beetles (SHB) Aethina tumida Murray were studied. The natural diets evaluated were brood, pollen, honey and their various combinations. Duration of mating (1 day versus 2 days), ratio of female (F...

  15. Alternative Mating Tactics in Male Chameleons (Chamaeleo chamaeleon) Are Evident in Both Long-Term Body Color and Short-Term Courtship Pattern

    PubMed Central

    Keren-Rotem, Tammy; Levy, Noga; Wolf, Lior; Bouskila, Amos; Geffen, Eli

    2016-01-01

    Alternative mating tactics in males of various taxa are associated with body color, body size, and social status. Chameleons are known for their ability to change body color following immediate environmental or social stimuli. In this study, we examined whether the differential appearance of male common chameleon during the breeding season is indeed an expression of alternative mating tactics. We documented body color of males and used computer vision techniques to classify images of individuals into discrete color patterns associated with seasons, individual characteristics, and social contexts. Our findings revealed no differences in body color and color patterns among males during the non-breeding season. However, during the breeding season males appeared in several color displays, which reflected body size, social status, and behavioral patterns. Furthermore, smaller and younger males resembled the appearance of small females. Consequently, we suggest that long-term color change in males during the breeding season reflects male alternative mating tactics. Upon encounter with a receptive female, males rapidly alter their appearance to that of a specific brief courtship display, which reflects their social status. The females, however, copulated indiscriminately in respect to male color patterns. Thus, we suggest that the differential color patterns displayed by males during the breeding season are largely aimed at inter-male signaling. PMID:27409771

  16. Fitness improvement of mass-reared sterile males of Ceratitis capitata (Vienna 8 strain) (Diptera: Tephritidae) after gut enrichment with probiotics.

    PubMed

    Hamden, Heithem; Guerfali, Meriem M'Saad; Fadhl, Selma; Saidi, Mouldi; Chevrier, Claude

    2013-04-01

    Successful mass rearing is crucial for sterile insect technique programs. It has been shown that the sterilizing process using gammaradiation results in damage to midgut tissue, cellular organelles, and gut microbiota of flies. This can be responsible for the inferiority of sterile males compared with wild males. A bacteria-enhanced diet could contribute to the improvement of the fly's fitness. We investigated ways of increasing the competitiveness of mass-reared Mediterranean fruit fly, Ceratitis capitata (Wiedemann) sterile males. We tested the hypothesis that the addition of beneficial bacteria to the larvae's diet would lead to a significant increase in their levels in the gut of the sterile adults and consequently improve their size and fitness. As expected, enriching the diet of mass-rearing Vienna-8 strain larvae with beneficial bacteria (Klebsiella pneumonia, Enterobacter spp., and Citrobacter freundii) resulted in increase in the number of Enterobacteriacae communities inhabiting the male's gut and a subsequent significant increase in the size of males and other morphometric traits and enhanced sexual performance of males at emergence.

  17. Identification and Functional Analysis of microRNAs Involved in the Anther Development in Cotton Genic Male Sterile Line Yu98-8A

    PubMed Central

    Yang, Xiaojie; Zhao, Yuanming; Xie, Deyi; Sun, Yao; Zhu, Xunlu; Esmaeili, Nardana; Yang, Zuoren; Wang, Ye; Yin, Guo; Lv, Shuping; Nie, Lihong; Tang, Zhongjie; Zhao, Fu’an; Li, Wu; Mishra, Neelam; Sun, Li; Zhu, Wei; Fang, Weiping

    2016-01-01

    Hybrid vigor contributes in a large way to the yield and quality of cotton (Gossypium hirsutum) fiber. Although microRNAs play essential regulatory roles in flower induction and development, it is still unclear if microRNAs are involved in male sterility, as the regulatory molecular mechanisms of male sterility in cotton need to be better defined. In this study, two independent small RNA libraries were constructed and sequenced from the young buds collected from the sporogenous cell formation to the meiosis stage of the male sterile line Yu98-8A and the near-isogenic line. Sequencing revealed 1588 and 1536 known microRNAs and 347 and 351 novel miRNAs from male sterile and male fertile libraries, respectively. MicroRNA expression profiles revealed that 49 conserved and 51 novel miRNAs were differentially expressed. Bioinformatic and degradome analysis indicated the regulatory complexity of microRNAs during flower induction and development. Further RT-qPCR and physiological analysis indicated that, among the different Kyoto Encyclopedia Gene and Genomes pathways, indole-3-acetic acid and gibberellic acid signaling transduction pathways may play pivotal regulatory functions in male sterility. PMID:27739413

  18. Casanovas are liars: behavioral syndromes, sperm competition risk, and the evolution of deceptive male mating behavior in live-bearing fishes.

    PubMed

    Bierbach, David; Makowicz, Amber M; Schlupp, Ingo; Geupel, Holger; Streit, Bruno; Plath, Martin

    2013-01-01

    Male reproductive biology can by characterized through competition over mates as well as mate choice. Multiple mating and male mate choice copying, especially in internally fertilizing species, set the stage for increased sperm competition, i.e., sperm of two or more males can compete for fertilization of the female's ova. In the internally fertilizing fish Poecilia mexicana, males respond to the presence of rivals with reduced expression of mating preferences (audience effect), thereby lowering the risk of by-standing rivals copying their mate choice. Also, males interact initially more with a non-preferred female when observed by a rival, which has been interpreted in previous studies as a strategy to mislead rivals, again reducing sperm competition risk (SCR). Nevertheless, species might differ consistently in their expression of aggressive and reproductive behaviors, possibly due to varying levels of SCR. In the current study, we present a unique data set comprising ten poeciliid species (in two cases including multiple populations) and ask whether species can be characterized through consistent differences in the expression of aggression, sexual activity and changes in mate choice under increased SCR. We found consistent species-specific differences in aggressive behavior, sexual activity as well as in the level of misleading behavior, while decreased preference expression under increased SCR was a general feature of all but one species examined. Furthermore, mean sexual activity correlated positively with the occurrence of potentially misleading behavior. An alternative explanation for audience effects would be that males attempt to avoid aggressive encounters, which would predict stronger audience effects in more aggressive species. We demonstrate a positive correlation between mean aggressiveness and sexual activity (suggesting a hormonal link as a mechanistic explanation), but did not detect a correlation between aggressiveness and audience effects. Suites

  19. Male and female condition influence mating performance and sexual receptivity in two tropical fruit flies (Diptera: Tephritidae) with contrasting life histories.

    PubMed

    Aluja, M; Rull, J; Sivinski, J; Trujillo, G; Pérez-Staples, D

    2009-12-01

    Recent recognition of widespread polyandry in insects has generated considerable interest in understanding why females mate multiple times and in identifying factors that affect mating rate and inhibit female remating. However, little attention has been paid to understanding the question from both a female and male perspective, particularly with respect to factors that may simultaneously influence female remating rates. Here, we report on a study aimed at ascertaining the possible interactive effects that male and female size and diet, and female access to a host could have on mating latency, probability, and duration and female refractory period using two tropical fruit fly species with contrasting life histories. Of all factors tested, adult diet played the most significant role. Both Anastrepha ludens and Anastrepha obliqua males which had constant access to protein and sucrose mated more often, had shorter copulations and induced longer refractory periods in females than males fed a low quality diet (sucrose offered every third day). Female size and the interaction with male diet determined how quickly female A. ludens mated for the first time. Smaller females mated sooner with low quality fed males than with high quality fed males while there was no difference for large females, suggesting that male choice may be at play if high quality fed males discriminate against smaller females. Copulation duration also depended on both male and female nutritional condition, and the interaction between male diet and female size and diet. Large and high quality fed females had shorter copulations regardless of male condition. Importantly, for A. ludens, female refractory period depended on male size and the nutritional condition of both males and females, which could indicate that for this species, female receptivity does not depend only on the condition of the male ejaculate. For A. obliqua refractory period was associated with the interaction between male size and diet

  20. Treatment with arginine vasotocin alters mating calls and decreases call attractiveness in male túngara frogs.

    PubMed

    Kime, Nicole M; Whitney, Tina K; Ryan, Michael J; Rand, A Stanley; Marler, Catherine A

    2010-01-15

    The peptide hormone arginine vasotocin (AVT) and its mammalian homolog arginine vasopressin modulate a variety of social behaviors in vertebrates. In anurans, AVT influences the production of advertisement calls, the acoustic signals that males use to attract females and repel rival males. In this study, we investigate the effects of AVT on call characteristics in the túngara frog (Physalaemus pustulosus). Túngara frogs produce a "whine" that is important for species recognition; they may also produce a second, attractive call component, the "chuck". We used a field playback experiment to determine changes in male calling behavior following treatment with AVT. A previous study showed that AVT alters call rate and the production of chucks; in the current analysis, we focus on changes in the whine. Males produce shorter whines with higher initial frequencies following treatment with AVT. Call changes do not vary with a social stimulus. We also used female phonotaxis experiments to investigate the effects of call changes on female mate choice. Females disfavor the calls produced by males treated with exogenous AVT. We suggest that AVT influences motivation to call and the motor control of call production, but that over-stimulation of the vocal system limited the production of attractive calls in this experimental context.

  1. Reduced expression of CDP-DAG synthase changes lipid composition and leads to male sterility in Drosophila

    PubMed Central

    Laurinyecz, Barbara; Péter, Mária; Vedelek, Viktor; Kovács, Attila L.; Juhász, Gábor; Maróy, Péter; Vígh, László; Balogh, Gábor; Sinka, Rita

    2016-01-01

    Drosophila spermatogenesis is an ideal system to study the effects of changes in lipid composition, because spermatid elongation and individualization requires extensive membrane biosynthesis and remodelling. The bulk of transcriptional activity is completed with the entry of cysts into meiotic division, which makes post-meiotic stages of spermatogenesis very sensitive to even a small reduction in gene products. In this study, we describe the effect of changes in lipid composition during spermatogenesis using a hypomorphic male sterile allele of the Drosophila CDP-DAG synthase (CdsA) gene. We find that the CdsA mutant shows defects in spermatid individualization and enlargement of mitochondria and the axonemal sheath of the spermatids. Furthermore, we could genetically rescue the male sterile phenotype by overexpressing Phosphatidylinositol synthase (dPIS) in a CdsA mutant background. The results of lipidomic and genetic analyses of the CdsA mutant highlight the importance of correct lipid composition during sperm development and show that phosphatidic acid levels are crucial in late stages of spermatogenesis. PMID:26791243

  2. PMS1T, producing phased small-interfering RNAs, regulates photoperiod-sensitive male sterility in rice

    PubMed Central

    Fan, Yourong; Yang, Jiangyi; Mathioni, Sandra M.; Yu, Jinsheng; Shen, Jianqiang; Yang, Xuefei; Wang, Lei; Zhang, Qinghua; Cai, Zhaoxia; Xu, Caiguo; Li, Xianghua; Xiao, Jinghua; Zhang, Qifa

    2016-01-01

    Phased small-interfering RNAs (phasiRNAs) are a special class of small RNAs, which are generated in 21- or 24-nt intervals from transcripts of precursor RNAs. Although phasiRNAs have been found in a range of organisms, their biological functions in plants have yet to be uncovered. Here we show that phasiRNAs generated by the photopheriod-sensetive genic male sterility 1 (Pms1) locus were associated with photoperiod-sensitive male sterility (PSMS) in rice, a germplasm that started the two-line hybrid rice breeding. The Pms1 locus encodes a long-noncoding RNA PMS1T that was preferentially expressed in young panicles. PMS1T was targeted by miR2118 to produce 21-nt phasiRNAs that preferentially accumulated in the PSMS line under long-day conditions. A single nucleotide polymorphism in PMS1T nearby the miR2118 recognition site was critical for fertility change, likely leading to differential accumulation of the phasiRNAs. This result suggested possible roles of phasiRNAs in reproductive development of rice, demonstrating the potential importance of this RNA class as regulators in biological processes. PMID:27965387

  3. Fine mapping of the epistatic suppressor gene (esp) of a recessive genic male sterility in rapeseed (Brassica napus L.).

    PubMed

    Xu, Zhenghua; Xie, Yanzhou; Hong, Dengfeng; Liu, Pingwu; Yang, Guangsheng

    2009-09-01

    9012AB, a recessive genic male sterility (RGMS) line derived from spontaneous mutation in Brassica napus, has been playing an important role in rapeseed hybrid production in China. The male sterility of 9012AB is controlled by two recessive genes (ms3 and ms4) interacting with one recessive epistatic suppressor gene (esp). The objective of this study was to develop PCR-based markers tightly linked to the esp gene and construct a high-resolution map surrounding the esp gene. From the survey of 512 AFLP primer combinations, 3 tightly linked AFLP markers were obtained and successfully converted to codominant or dominant SCAR markers. Furthermore, a codominant SSR marker (Ra2G08) associated with the esp gene was identified through genetic map integration. For fine mapping of the esp gene, these PCR-based markers were analyzed in a large BC1 population of 2545 plants. The esp gene was then genetically restricted to a region of 1.03 cM, 0.35 cM from SSR marker Ra2G08 and 0.68 cM from SCAR marker WSC6. The SCAR marker WSC5 co-segregated with the target gene. These results lay a solid foundation for map-based cloning of esp and will facilitate the selection of RGMS lines and their temporary maintainers.

  4. Aberrant Meiotic Prophase I Leads to Genic Male Sterility in the Novel TE5A Mutant of Brassica napus

    PubMed Central

    Yan, Xiaohong; Zeng, Xinhua; Wang, Shasha; Li, Keqi; Yuan, Rong; Gao, Hongfei; Luo, Junling; Liu, Fang; Wu, Yuhua; Li, Yunjing; Zhu, Li; Wu, Gang

    2016-01-01

    Genic male sterility (GMS) has already been extensively utilized for hybrid rapeseed production. TE5A is a novel thermo-sensitive dominant GMS line in Brassica napus, however, its mechanisms of GMS remain largely unclear. Histological and Transmission electron microscopy (TEM) analyses of anthers showed that the male gamete development of TE5A was arrested at meiosis prophase I. EdU uptake of S-phase meiocytes revealed that the TE5A mutant could accomplish DNA replication, however, chromosomal and fluorescence in situ hybridization (FISH) analyses of TE5A showed that homologous chromosomes could not pair, synapse, condense and form bivalents. We then analyzed the transcriptome differences between young floral buds of sterile plants and its near-isogenic fertile plants through RNA-Seq. A total of 3,841 differentially expressed genes (DEGs) were obtained, some of which were associated with homologous chromosome behavior and cell cycle control during meiosis. Dynamic expression changes of selected candidate DEGs were then analyzed at different anther developmental stages. The present study not only demonstrated that the TE5A mutant had defects in meiotic prophase I via detailed cytological analysis, but also provided a global insight into GMS-associated DEGs and elucidated the mechanisms of GMS in TE5A through RNA-Seq. PMID:27670217

  5. Colour Cues That Are Not Directly Attached to the Body of Males Do Not Influence the Mate Choice of Zebra Finches.

    PubMed

    Krause, E Tobias

    2016-01-01

    Mate choice decisions of female zebra finches are generally thought to rely on the assessment of male quality, which includes the specific ornamentation of males. A commonly used paradigm to experimentally manipulate a male's attractiveness is to add a coloured leg ring to the bird. Some studies have shown that female zebra finches prefer or alter their investment in males that have an additional red leg ring compared with males with green leg rings. Whether the coloured artificial ornaments need to be attached to the male's body or whether environmental colouration could have a similar effect on male attractiveness remains unclear. Here, I investigated this novel context to determine whether female choice between males is affected by environmental colour cues that are not directly attached to the male's body in four experiments involving 220 zebra finches (Taeniopygia guttata). A first experiment revealed that females chose males with red colour cues in the environmental background over males with green cues in the background. Based on this finding, I conducted follow-up experiments to obtain a deeper understanding of how environmental colour cues affect mate choice. Therefore, I examined whether female choice behaviour or male behaviour was altered in two additional experiments. Both experiments failed to show any effects of environmental colour cues on female choice or on male behaviour. Therefore, I replicated the initial experiment in a fourth experiment. Again replication failed; thus, the initial results indicating that environmental colouration affects mate choice behaviour of female zebra finches were not supported by the three subsequent experiments; thus, the outcome of the first experiment seems to be a false positive. Taking my results together, I found no robust support for the idea that environmental colour cues that are not directly attached to the body of male zebra finches affect female mate choice decisions.

  6. Genetics of reproductive isolation in the Drosophila simulans clade: DNA marker-assisted mapping and characterization of a hybrid-male sterility gene, Odysseus (Ods).

    PubMed

    Perez, D E; Wu, C I; Johnson, N A; Wu, M L

    1993-05-01

    In this study, we address the question of whether there exist major genes that cause complete male sterility in the interspecific hybrids of Drosophila and, if they do, how these genes may be characterized at the molecular level. Our approach is to introgress small segments of the X chromosome from Drosophila mauritiana (or Drosophila sechellia) into Drosophila simulans by repeated backcrosses for more than 20 generations. The introgressions are monitored by both visible mutations and a series of DNA markers. We compare the extent of introgressions that cause male sterility with those that do not. If a major sterility factor exists, there should be a sharp boundary between these two classes of introgressions and their breakpoints should demarcate such a gene. Furthermore, if male sterility is the only major fitness effect associated with the introgression, recombination analysis should yield a pattern predicted by the classical three-point cross. Both the genetic and molecular analyses suggest the presence of a major sterility factor from D. mauritiana, which we named Odysseus (Ods), in the cytological interval of 16D. We thus formalize three criteria for inferring the existence of a major gene within an introgression: (1) complete penetrance of sterility, (2) complementarity in recombination analysis, and (3) physical demarcation. Introgressions of Ods from D. sechellia do not cause sterility. Twenty-two introgressions in our collection have breakpoints in this interval of about 500 kb, making it possible to delineate Ods more precisely for molecular identification. The recombination analysis also reveals the complexity of the introgressed segments--even relatively short ones may contain a second male sterility factor and partial viability genes and may also interfere with crossovers. The spermatogenic defects associated with Ods and/or a second factor were characterized by phase-contrast microscopy.

  7. iTRAQ-facilitated proteomic profiling of anthers from a photosensitive male sterile mutant and wild-type cotton (Gossypium hirsutum L.).

    PubMed

    Liu, Ji; Pang, Chaoyou; Wei, Hengling; Song, Meizhen; Meng, Yanyan; Ma, Jianhui; Fan, Shuli; Yu, Shuxun

    2015-08-03

    Male sterility is a common phenomenon in flowering plants, and it has been successfully developed in several crops by taking advantage of heterosis. Cotton (Gossypium hirsutum L.) is an important economic crop, used mainly for the production of textile fiber. Using a space mutation breeding technique, a novel photosensitive genetic male sterile mutant CCRI9106 was isolated from the wild-type upland cotton cultivar CCRI040029. To use CCRI9106 in cotton hybrid breeding, it is of great importance to study the molecular mechanisms of its male sterility. Here, histological and iTRAQ-facilitated proteomic analyses of anthers were performed to explore male sterility mechanisms of the mutant. Scanning and transmission electron microscopy of the anthers showed that the development of pollen wall in CCRI9106 was severely defective with a lack of exine formation. At the protein level, 6121 high-confidence proteins were identified and 325 of them showed differential expression patterns between mutant and wild-type anthers. The proteins up- or down-regulated in MT anthers were mainly involved in exine formation, protein degradation, calcium ion binding,etc. These findings provide valuable information on the proteins involved in anther and pollen development, and contribute to elucidate the mechanism of male sterility in upland cotton.

  8. High-resolution fine mapping of ps-2, a mutated gene conferring functional male sterility in tomato due to non-dehiscent anthers.

    PubMed

    Gorguet, Benoit; Schipper, Danny; van Heusden, Adriaan W; Lindhout, Pim

    2006-11-01

    Functional male sterility is an important trait for the production of hybrid seeds. Among the genes coding for functional male sterility in tomato is the positional sterility gene ps-2. ps-2 is monogenic recessive, confers non-dehiscent anthers and is the most suitable for practical uses. In order to have tools for molecular-assisted selection (MAS) we fine mapped the ps-2 locus. This was done in an F(2) segregating population derived from the interspecific cross between a functionally male sterile line (ps-2/ps-2; Solanum lycopersicum) and a functionally male fertile line (S. pimpinellifolium). Here we report the procedure that has led to the high-resolution fine mapping of the ps-2 locus in a 1.65 cM interval delimited by markers T0958 and T0635 on the short arm of Chromosome 4. The presence of many COS markers in the local high-resolution map allowed us to study the synteny between tomato and Arabidopsis at the ps-2 locus region. No obvious candidate gene for ps-2 was identified among the known functional male sterility genes in Arabidopsis.

  9. Mathematical model in controlling dengue transmission with sterile mosquito strategies

    NASA Astrophysics Data System (ADS)

    Aldila, D.; Nuraini, N.; Soewono, E.

    2015-09-01

    In this article, we propose a mathematical model for controlling dengue disease transmission with sterile mosquito techniques (SIT). Sterile male introduced from lab in to habitat to compete with wild male mosquito for mating with female mosquito. Our aim is to displace gradually the natural mosquito from the habitat. Mathematical model analysis for steady states and the basic reproductive ratio are performed analytically. Numerical simulation are shown in some different scenarios. We find that SIT intervention is potential to controlling dengue spread among humans population

  10. [Isolation and identification of specific sequences correlated to cytoplasmic male sterility and fertile maintenance in cauliflower (Brassica oleracea var. botrytis)].

    PubMed

    Wang, Chun Guo; Chen, Xiao Qiang; Li, Hui; Zhao, Qian Cheng; Sun, De Ling; Song, Wen Qin

    2008-02-01

    Analysis of ISSR (Inter-Simple Sequence Repeat) and DDRT-PCR (Differential Display Reverse Transcriptase Polymerase Chain Reaction) was performed between cytoplasmic male sterility cauliflower ogura-A and its corresponding maintainer line ogura-B. Totally, 306 detectable bands were obtained by ISSR using thirty oligonucleotide primers. Commonly, six to twelve bands were produced per primer. Among all these primers only the amplification of primer ISSR3 was polymorphic, an 1100 bp specific band was only detected in maintainer line, named ISSR3(1100). Analysis of this sequence indicated that ISSR3(1100) was high homologous with the corresponding sequences of mitochondrial genome in Brassica napus and Arabidopsis thaliana,which suggested that ISSR3(1100) may derive from mitochondrial genome in cauliflower. To carry out DDRT-PCR analysis, three anchor primers and fifteen random primers were selected to combine. Totally, 1122 bands from 1 000 bp to 50 bp were detected. However, only four bands, named ogura-A 205, ogura-A383, ogura-B307 and ogura-B352, were confirmed to be different display in both lines. This result was further identified by reverse Northern dot blotting analysis. Among these four bands, ogura-A205 and ogura-A383 only express in cytoplasmic male sterility line, while ogura-B307 and ogura-B352 were only detected in maintainer line. Analysis of these sequences indicated that it was the first time that these four sequences were reported in cauliflower. Interestingly, ogura-A205 and ogura-B307 did not exhibit any similarities to other reported sequences in other species, more investigations were required to obtain further information. ogura-A383 and ogura-B352 were also two new sequences, they showed high similarities to corresponding chloroplast sequences of Arabidopsis thaliana and Brassica rapa subsp. pekinensis. So we speculated that these two sequences may derive from chloroplast genome. All these results obtained in this study offer new and

  11. Sequencing and annotation of the chloroplast DNAs and identification of polymorphisms distinguishing normal male-fertile and male-sterile cytoplasms of onion.

    PubMed

    von Kohn, Christopher; Kiełkowska, Agnieszka; Havey, Michael J

    2013-12-01

    Male-sterile (S) cytoplasm of onion is an alien cytoplasm introgressed into onion in antiquity and is widely used for hybrid seed production. Owing to the biennial generation time of onion, classical crossing takes at least 4 years to classify cytoplasms as S or normal (N) male-fertile. Molecular markers in the organellar DNAs that distinguish N and S cytoplasms are useful to reduce the time required to classify onion cytoplasms. In this research, we completed next-generation sequencing of the chloroplast DNAs of N- and S-cytoplasmic onions; we assembled and annotated the genomes in addition to identifying polymorphisms that distinguish these cytoplasms. The sizes (153 538 and 153 355 base pairs) and GC contents (36.8%) were very similar for the chloroplast DNAs of N and S cytoplasms, respectively, as expected given their close phylogenetic relationship. The size difference was primarily due to small indels in intergenic regions and a deletion in the accD gene of N-cytoplasmic onion. The structures of the onion chloroplast DNAs were similar to those of most land plants with large and small single copy regions separated by inverted repeats. Twenty-eight single nucleotide polymorphisms, two polymorphic restriction-enzyme sites, and one indel distributed across 20 chloroplast genes in the large and small single copy regions were selected and validated using diverse onion populations previously classified as N or S cytoplasmic using restriction fragment length polymorphisms. Although cytoplasmic male sterility is likely associated with the mitochondrial DNA, maternal transmission of the mitochondrial and chloroplast DNAs allows for polymorphisms in either genome to be useful for classifying onion cytoplasms to aid the development of hybrid onion cultivars.

  12. Colour Cues That Are Not Directly Attached to the Body of Males Do Not Influence the Mate Choice of Zebra Finches

    PubMed Central

    2016-01-01

    Mate choice decisions of female zebra finches are generally thought to rely on the assessment of male quality, which includes the specific ornamentation of males. A commonly used paradigm to experimentally manipulate a male’s attractiveness is to add a coloured leg ring to the bird. Some studies have shown that female zebra finches prefer or alter their investment in males that have an additional red leg ring compared with males with green leg rings. Whether the coloured artificial ornaments need to be attached to the male’s body or whether environmental colouration could have a similar effect on male attractiveness remains unclear. Here, I investigated this novel context to determine whether female choice between males is affected by environmental colour cues that are not directly attached to the male’s body in four experiments involving 220 zebra finches (Taeniopygia guttata). A first experiment revealed that females chose males with red colour cues in the environmental background over males with green cues in the background. Based on this finding, I conducted follow-up experiments to obtain a deeper understanding of how environmental colour cues affect mate choice. Therefore, I examined whether female choice behaviour or male behaviour was altered in two additional experiments. Both experiments failed to show any effects of environmental colour cues on female choice or on male behaviour. Therefore, I replicated the initial experiment in a fourth experiment. Again replication failed; thus, the initial results indicating that environmental colouration affects mate choice behaviour of female zebra finches were not supported by the three subsequent experiments; thus, the outcome of the first experiment seems to be a false positive. Taking my results together, I found no robust support for the idea that environmental colour cues that are not directly attached to the body of male zebra finches affect female mate choice decisions. PMID:27977719

  13. Mating system of the European hornet Vespa crabro: male seeking strategies and evidence for the involvement of a sex pheromone.

    PubMed

    Spiewok, S; Schmolz, E; Ruther, J

    2006-12-01

    We describe details of the mate finding strategy of drones of the European hornet, Vespa crabro, and present evidence for the involvement of sex pheromones. Tests were carried out with free flying drones in natural habitats. Males patrolled the nest site itself, as well as nearby nonresource-based sites, without showing territorial behavior. Patrolling was restricted to sunny spots in the vegetation, and thus, the locations changed throughout the day. Drones were attracted to both caged gynes and to dead workers treated with gyne extracts, indicating the presence of a female-produced sex attractant. Treated workers also elicited copulation attempts by the attracted drones. Extracts from gynes, workers, and drones contained exclusively cuticular lipids, and the profile from gynes was much more diverse than that of workers and drones. The most striking differences observed related to the alkenes, monomethyl- and dimethylalkanes. The results provide a lead for potential attracting and copulation-releasing semiochemicals in V. crabro.

  14. Cytomixis and meiotic abnormalities during microsporogenesis are responsible for male sterility and chromosome variations in Houttuynia cordata.

    PubMed

    Guan, J-Z; Wang, J-J; Cheng, Z-H; Liu, Y; Li, Z-Y

    2012-01-17

    Houttuynia cordata (Saururaceae) is a leaf vegetable and a medicinal herb througout much of Asia. Cytomixis and meiotic abnormalities during microsporogenesis were found in two populations of H. cordata with different ploidy levels (2n = 38, 96). Cytomixis occurred in pollen mother cells during meiosis at high frequencies and with variable degrees of chromatin/chromosome transfer. Meiotic abnormalities, such as chromosome laggards, asymmetric segregation and polyads, also prevailed in pollen mother cells at metaphase of the first division and later stages. They were caused by cytomixis and resulted in very low pollen viability and male sterility. Pollen mother cells from the population with 2n = 38 showed only simultaneous cytokinesis, but most pollen mother cells from the population with 2n = 96 showed successive cytokinesis; a minority underwent simultaneous cytokinesis. Cytomixis and irregular meiotic divisions appear to be the origin of the intraspecific polyploidy in this species, which has large variations in chromosome numbers.

  15. A novel function for the Hox gene Abd-B in the male accessory gland regulates the long-term female post-mating response in Drosophila.

    PubMed

    Gligorov, Dragan; Sitnik, Jessica L; Maeda, Robert K; Wolfner, Mariana F; Karch, François

    2013-03-01

    In insects, products of the male reproductive tract are essential for initiating and maintaining the female post-mating response (PMR). The PMR includes changes in egg laying, receptivity to courting males, and sperm storage. In Drosophila, previous studies have determined that the main cells of the male accessory gland produce some of the products required for these processes. However, nothing was known about the contribution of the gland's other secretory cell type, the secondary cells. In the course of investigating the late functions of the homeotic gene, Abdominal-B (Abd-B), we discovered that Abd-B is specifically expressed in the secondary cells of the Drosophila male accessory gland. Using an Abd-B BAC reporter coupled with a collection of genetic deletions, we discovered an enhancer from the iab-6 regulatory domain that is responsible for Abd-B expression in these cells and that apparently works independently from the segmentally regulated chromatin domains of the bithorax complex. Removal of this enhancer results in visible morphological defects in the secondary cells. We determined that mates of iab-6 mutant males show defects in long-term egg laying and suppression of receptivity, and that products of the secondary cells are influential during sperm competition. Many of these phenotypes seem to be caused by a defect in the storage and gradual release of sex peptide in female mates of iab-6 mutant males. We also found that Abd-B expression in the secondary cells contributes to glycosylation of at least three accessory gland proteins: ovulin (Acp26Aa), CG1656, and CG1652. Our results demonstrate that long-term post-mating changes observed in mated females are not solely induced by main cell secretions, as previously believed, but that secondary cells also play an important role in male fertility by extending the female PMR. Overall, these discoveries provide new insights into how these two cell types cooperate to produce and maintain a robust female PMR.

  16. Do males time their mate-guarding effort with the fertile phase in order to secure fertilisation in Cayo Santiago rhesus macaques?

    PubMed

    Dubuc, Constance; Muniz, Laura; Heistermann, Michael; Widdig, Anja; Engelhardt, Antje

    2012-05-01

    In contrast to most mammalian species, female sexual activity is not limited to the fertile phase of the ovarian cycle in anthropoid primates, which has long been proposed to conceal the timing of ovulation to males. It is now generally believed that females are still most attractive during the fertile phase, leading to high-ranking males successfully mate-guarding them specifically during this period. While studies conducted in species exhibiting exaggerated sexual swellings (probabilistic signal of the fertile phase) have generally supported this hypothesis, mixed support comes from others. Here, we investigated whether high-ranking males timed mate-guarding effort towards female fertile phases in rhesus macaques (Macaca mulatta). In this species, adult females do not exhibit sexual swellings, but undergo facial skin colour variation, an alternative oestrogen-dependent graded-signal of female reproductive status. We collected behavioural, hormonal and genetic paternity data during two mating seasons for one group of the free-ranging population of Cayo Santiago. Our results show that mate-guarding by top-ranking males did not completely cover the entire female fertile phase and that this tactic accounted for only 30-40% of all fertilisations observed. Males tended to prolong mate-guarding into the luteal phase (null probability of fertilisation), which mirrors the pattern of male attraction to female facial colour reported in an earlier study. These findings suggest that males may have limited knowledge regarding the exact timing of females' fertile phase in rhesus macaques, which presumably allows females to gain more control over reproduction relative to other anthropoid primate species.

  17. Influences of Mating Group Composition on the Behavioral Time-Budget of Male and Female Alpine Ibex (Capra ibex) during the Rut

    PubMed Central

    Tettamanti, Federico; Viblanc, Vincent A.

    2014-01-01

    During the rut, polygynous ungulates gather in mixed groups of individuals of different sex and age. Group social composition, which may vary on a daily basis, is likely to have strong influences on individual’s time-budget, with emerging properties at the group-level. To date, few studies have considered the influence of group composition on male and female behavioral time budget in mating groups. Focusing on a wild population of Alpine ibex, we investigated the influence of group composition (adult sex ratio, the proportion of dominant to subordinate males, and group size) on three behavioral axes obtained by Principal Components Analysis, describing male and female group time-budget. For both sexes, the first behavioral axis discerned a trade-off between grazing and standing/vigilance behavior. In females, group vigilance behavior increased with increasingly male-biased sex ratio, whereas in males, the effect of adult sex ratio on standing/vigilance behavior depended on the relative proportion of dominant males in the mating group. The second axis characterized courtship and male-male agonistic behavior in males, and moving and male-directed agonistic behavior in females. Mating group composition did not substantially influence this axis in males. However, moving and male-directed agonistic behavior increased at highly biased sex ratios (quadratic effect) in females. Finally, the third axis highlighted a trade-off between moving and lying behavior in males, and distinguished moving and female-female agonistic behavior from lying behavior in females. For males, those behaviors were influenced by a complex interaction between group size and adult sex ratio, whereas in females, moving and female-female agonistic behaviors increased in a quadratic fashion at highly biased sex ratios, and also increased with increasing group size. Our results reveal complex behavioral trade-offs depending on group composition in the Alpine ibex, and emphasize the importance of

  18. Transcriptomic Analysis Reveals New Insights into High-Temperature-Dependent Glume-Unclosing in an Elite Rice Male Sterile Line

    PubMed Central

    Fu, Chongyun; Wang, Feng; Liu, Wuge; Liu, Dilin; Li, Jinhua; Zhu, Manshan; Liao, Yilong; Liu, Zhenrong; Huang, Huijun; Zeng, Xueqin; Ma, Xiaozhi

    2017-01-01

    Glume-unclosing after anthesis is a widespread phenomenon in hybrid rice and also a maternal hereditary trait. The character of Glume-unclosing in rice male sterile lines also seriously influences germination rate and the commercial quality of hybrid rice seeds. We validated that the type of glume-unclosing after anthesis in the elite rice thermo-sensitive genic male sterile (TGMS) line RGD-7S was caused by high temperature. Transcriptomic sequencing of rice panicles was performed to explore the change of transcript profiles under four conditions: pre- and post-anthesis under high temperature (HRGD0 and HRGD1), and pre- and post-anthesis under low temperature (LRGD0 and LRGD1). We identified a total of 14,540 differentially expressed genes (DEGs) including some heat shock factors (HSFs) across the four samples. We found that more genes were up-regulated than down-regulated in the sample pair HRGD1vsHRGD0. These up-regulated genes were significantly enriched in the three biological processes of carbohydrate metabolism, response to water and cell wall macromolecular metabolism. Simultaneously, we also found that the HSF gene OsHsfB1 was specially up-regulated in HRGD1vsHRGD0. However, the down-regulated DEGs in LRGD1vsLRGD0 were remarkably clustered in the biological process of carbohydrate metabolism. This suggests that carbohydrate metabolism may play a key role in regulation of glume-unclosing under high temperature in RGD-7S. We also analyzed the expression pattern of genes enriched in carbohydrate metabolism and several HSF genes under different conditions and provide new insights into the cause of rice glume-unclosing. PMID:28261226

  19. Contrasting reproductive strategies of triploid hybrid males in vertebrate mating systems.

    PubMed

    Pruvost, N B M; Mikulíček, P; Choleva, L; Reyer, H-U

    2015-01-01

    The scarcity of parthenogenetic vertebrates is often attributed to their 'inferior' mode of clonal reproduction, which restricts them to self-reproduce their own genotype lineage and leaves little evolutionary potential with regard to speciation and evolution of sexual reproduction. Here, we show that for some taxa, such uniformity does not hold. Using hybridogenetic water frogs (Pelophylax esculentus) as a model system, we demonstrate that triploid hybrid males from two geographic regions exhibit very different reproductive modes. With an integrative data set combining field studies, crossing experiments, flow cytometry and microsatellite analyses, we found that triploid hybrids from Central Europe are rare, occur in male sex only and form diploid gametes of a single clonal lineage. In contrast, triploid hybrids from north-western Europe are widespread, occur in both sexes and produce recombined haploid gametes. These differences translate into contrasting reproductive roles between regions. In Central Europe, triploid hybrid males sexually parasitize diploid hybrids and just perpetuate their own genotype--which is the usual pattern in parthenogens. In north-western Europe, on the other hand, the triploid males are gamete donors for diploid hybrids, thereby stabilizing the mixed 2n-3n hybrid populations. By demonstrating these contrasting roles in male reproduction, we draw attention to a new significant evolutionary potential for animals with nonsexual reproduction, namely reproductive plasticity.

  20. Relationship between male sterility and β-1,3-glucanase activity and callose deposition-related gene expression in wheat (Triticum aestivum L.).

    PubMed

    Liu, H Z; Zhang, G S; Zhu, W W; Ba, Q S; Niu, N; Wang, J W; Ma, S C; Wang, J S

    2015-01-26

    In previous studies, we first isolated one different protein β-1,3-glucanase using two-dimensional electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry from normal wheat (Triticum aestivum L.) and chemical hybridization agent-induced male sterility (CIMS) wheat. In this experiment, β-1,3-glucanase activity and the expression of a callose deposition-related gene, UDP-glucose phosphorylase (UGPase), were determinate in normal, CIMS, and genetic male sterility (GS) wheat. β-1,3-glucanase activity was significantly different between the fertile and sterile lines during callose synthesis and degradation, but there was no difference between CIMS and GS wheat. The UGPase gene of callose deposition was highly expressed in the meiophase and sharply decreased in the tetrad stage. However, the expression of the UGPase gene was significantly different between the fertile and sterile lines. These data indicated that β-1,3-glucanase activity and the expression of the UGPase gene play important roles in the male sterility of wheat. Consequently, pollen mother cells (PMCs) might degenerate at the early meiosis stage, and differences in UGPase gene expression and β-1,3-glucanase activity might eventually result in complete pollen collapse. In addition, the critical period of anther abortion might be the meiosis stage to the tetrad stage rather than what we previously thought, the mononuclear period.

  1. Specific down-regulation of spermatogenesis genes targeted by 22G RNAs in hybrid sterile males associated with an X-Chromosome introgression.

    PubMed

    Li, Runsheng; Ren, Xiaoliang; Bi, Yu; Ho, Vincy Wing Sze; Hsieh, Chia-Ling; Young, Amanda; Zhang, Zhihong; Lin, Tingting; Zhao, Yanmei; Miao, Long; Sarkies, Peter; Zhao, Zhongying

    2016-09-01

    Hybrid incompatibility (HI) prevents gene flow between species, thus lying at the heart of speciation genetics. One of the most common HIs is male sterility. Two superficially contradictory observations exist for hybrid male sterility. First, an introgression on the X Chromosome is more likely to produce male sterility than on autosome (so-called large-X theory); second, spermatogenesis genes are enriched on the autosomes but depleted on the X Chromosome (demasculinization of X Chromosome). Analysis of gene expression in Drosophila hybrids suggests a genetic interaction between the X Chromosome and autosomes that is essential for male fertility. However, the prevalence of such an interaction and its underlying mechanism remain largely unknown. Here we examine the interaction in nematode species by contrasting the expression of both coding genes and transposable elements (TEs) between hybrid sterile males and its parental nematode males. We use two lines of hybrid sterile males, each carrying an independent introgression fragment from Caenorhabditis briggsae X Chromosome in an otherwise Caenorhabditis nigoni background, which demonstrate similar defects in spermatogenesis. We observe a similar pattern of down-regulated genes that are specific for spermatogenesis between the two hybrids. Importantly, the down-regulated genes caused by the X Chromosome introgressions show a significant enrichment on the autosomes, supporting an epistatic interaction between the X Chromosome and autosomes. We investigate the underlying mechanism of the interaction by measuring small RNAs and find that a subset of 22G RNAs specifically targeting the down-regulated spermatogenesis genes is significantly up-regulated in hybrids, suggesting that perturbation of small RNA-mediated regulation may contribute to the X-autosome interaction.

  2. Specific down-regulation of spermatogenesis genes targeted by 22G RNAs in hybrid sterile males associated with an X-Chromosome introgression

    PubMed Central

    Li, Runsheng; Ren, Xiaoliang; Bi, Yu; Ho, Vincy Wing Sze; Hsieh, Chia-Ling; Young, Amanda; Zhang, Zhihong; Lin, Tingting; Zhao, Yanmei; Miao, Long; Sarkies, Peter

    2016-01-01

    Hybrid incompatibility (HI) prevents gene flow between species, thus lying at the heart of speciation genetics. One of the most common HIs is male sterility. Two superficially contradictory observations exist for hybrid male sterility. First, an introgression on the X Chromosome is more likely to produce male sterility than on autosome (so-called large-X theory); second, spermatogenesis genes are enriched on the autosomes but depleted on the X Chromosome (demasculinization of X Chromosome). Analysis of gene expression in Drosophila hybrids suggests a genetic interaction between the X Chromosome and autosomes that is essential for male fertility. However, the prevalence of such an interaction and its underlying mechanism remain largely unknown. Here we examine the interaction in nematode species by contrasting the expression of both coding genes and transposable elements (TEs) between hybrid sterile males and its parental nematode males. We use two lines of hybrid sterile males, each carrying an independent introgression fragment from Caenorhabditis briggsae X Chromosome in an otherwise Caenorhabditis nigoni background, which demonstrate similar defects in spermatogenesis. We observe a similar pattern of down-regulated genes that are specific for spermatogenesis between the two hybrids. Importantly, the down-regulated genes caused by the X Chromosome introgressions show a significant enrichment on the autosomes, supporting an epistatic interaction between the X Chromosome and autosomes. We investigate the underlying mechanism of the interaction by measuring small RNAs and find that a subset of 22G RNAs specifically targeting the down-regulated spermatogenesis genes is significantly up-regulated in hybrids, suggesting that perturbation of small RNA-mediated regulation may contribute to the X-autosome interaction. PMID:27197225

  3. Mating behavior and fertility of broiler breeder males reared on shortened growth cycles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the more difficult tasks when raising broiler breeder cockerels is controlling weight gain in the rearing house without inflicting excess stress. This is a period of time for the young male when many portions of reproductive system are in the formative stages and, if neglected, can have lif...

  4. Female mating receptivity after injection of male-derived extracts in Callosobruchus maculatus.

    PubMed

    Yamane, Takashi; Miyatake, Takahisa; Kimura, Yoshinobu

    2008-12-01

    The effects of male-derived extracts on female receptivity were investigated in Callosobruchus maculatus (Coleoptera: Bruchidae). Injection of aqueous extracts of the male reproductive tract into the abdomen of females reduced receptivity. Aqueous extracts of male reproductive tracts were divided to three molecular weight (MW) fractions by ultrafiltration: Fractions: (I) MW<3 kDa, (II) 3-14 kDa, and (III)>14 kDa. Fraction II reduced female receptivity from 3h after injection, and Fraction III reduced female receptivity from 2 days after injection. On the other hand, no effect on receptivity was found for Fraction I. Furthermore, male reproductive tract organs were divided into accessory gland, testis, and seminal vesicle including the ejaculatory duct. Aqueous extracts of the seminal vesicle reduced receptivity of females immediately following injection, while aqueous extracts of the accessory gland reduced receptivity at the second day. The results suggest that the components of Fraction II existed in the seminal vesicle, and those of Fraction III in the accessory gland. The results of the present and the previous studies in Callosobruchus chinensis, a species closely related to C. maculatus, were compared and are discussed from the viewpoint of the significance of ejaculation in the two species.

  5. Telipogon peruvianus (Orchidaceae) Flowers Elicit Pre-Mating Behaviour in Eudejeania (Tachinidae) Males for Pollination

    PubMed Central

    Cairampoma, Lianka; Stauffer, Fred W.; Ayasse, Manfred

    2016-01-01

    Several neotropical orchid genera have been proposed as being sexually deceptive; however, this has been carefully tested in only a few cases. The genus Telipogon has long been assumed to be pollinated by male tachinid flies during pseudocopulatory events but no detailed confirmatory reports are available. Here, we have used an array of methods to elucidate the pollination mechanism in Telipogon peruvianus. The species presents flowers that have a mean floral longevity of 33 days and that are self-compatible, although spontaneous self-pollination does not occur. The flowers attract males of four tachinid species but only the males of an undescribed Eudejeania (Eudejeania aff. browni; Tachinidae) species are specific pollinators. Males visit the flowers during the first few hours of the day and the pollination success is very high (42% in one patch) compared with other sexually deceptive species. Female-seeking males are attracted to the flowers but do not attempt copulation with the flowers, as is usually described in sexually deceptive species. Nevertheless, morphological analysis and behavioural tests have shown an imperfect mimicry between flowers and females suggesting that the attractant stimulus is not based only on visual cues, as long thought. Challenging previous conclusions, our chemical analysis has confirmed that flowers of Telipogon release volatile compounds; however, the role of these volatiles in pollinator behaviour remains to be established. Pollinator behaviour and histological analyses indicate that Telipogon flowers possess scent-producing structures throughout the corolla. Our study provides the first confirmed case of (i) a sexually deceptive species in the Onciidinae, (ii) pollination by pre-copulatory behaviour and (iii) pollination by sexual deception involving tachinid flies. PMID:27812201

  6. Telipogon peruvianus (Orchidaceae) Flowers Elicit Pre-Mating Behaviour in Eudejeania (Tachinidae) Males for Pollination.

    PubMed

    Martel, Carlos; Cairampoma, Lianka; Stauffer, Fred W; Ayasse, Manfred

    2016-01-01

    Several neotropical orchid genera have been proposed as being sexually deceptive; however, this has been carefully tested in only a few cases. The genus Telipogon has long been assumed to be pollinated by male tachinid flies during pseudocopulatory events but no detailed confirmatory reports are available. Here, we have used an array of methods to elucidate the pollination mechanism in Telipogon peruvianus. The species presents flowers that have a mean floral longevity of 33 days and that are self-compatible, although spontaneous self-pollination does not occur. The flowers attract males of four tachinid species but only the males of an undescribed Eudejeania (Eudejeania aff. browni; Tachinidae) species are specific pollinators. Males visit the flowers during the first few hours of the day and the pollination success is very high (42% in one patch) compared with other sexually deceptive species. Female-seeking males are attracted to the flowers but do not attempt copulation with the flowers, as is usually described in sexually deceptive species. Nevertheless, morphological analysis and behavioural tests have shown an imperfect mimicry between flowers and females suggesting that the attractant stimulus is not based only on visual cues, as long thought. Challenging previous conclusions, our chemical analysis has confirmed that flowers of Telipogon release volatile compounds; however, the role of these volatiles in pollinator behaviour remains to be established. Pollinator behaviour and histological analyses indicate that Telipogon flowers possess scent-producing structures throughout the corolla. Our study provides the first confirmed case of (i) a sexually deceptive species in the Onciidinae, (ii) pollination by pre-copulatory behaviour and (iii) pollination by sexual deception involving tachinid flies.

  7. Analysis of Quantitative Traits in Two Long-Term Randomly Mated Soybean Populations I. Genetic Variances

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genetic effects of long term random mating and natural selection aided by genetic male sterility were evaluated in two soybean [Glycine max (L.) Merr.] populations: RSII and RSIII. Population means, variances, and heritabilities were estimated to determine the effects of 26 generations of random...

  8. Genetic and phenotypic correlations of quantitative traits in two long-term randomly mated soybean populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genetic effects of long term random mating and natural selection aided by genetic male sterility (gms) were evaluated in two soybean [Glycine max (L.) Merr.] populations designated: RSII and RSIII. These populations were evaluated in the field at three locations each with two replications. Genot...

  9. Central oxytocin receptors mediate mating-induced partner preferences and enhance correlated activation across forebrain nuclei in male prairie voles

    PubMed Central

    Johnson, Zachary V.; Walum, Hasse; Jamal, Yaseen A.; Xiao, Yao; Keebaugh, Alaine C.; Inoue, Kiyoshi; Young, Larry J.

    2016-01-01

    Oxytocin (OT) is a deeply conserved nonapeptide that acts both peripherally and centrally to modulate reproductive physiology and sociosexual behavior across divergent taxa, including humans. In vertebrates, the distribution of the oxytocin receptor (OTR) in the brain is variable within and across species, and OTR signaling is critical for a variety of species-typical social and reproductive behaviors, including affiliative and pair bonding behaviors in multiple socially monogamous lineages of fishes, birds, and mammals. Early work in prairie voles suggested that the endogenous OT system modulates mating-induced partner preference formation in females but not males; however, there is significant evidence that central OTRs may modulate pair bonding behavior in both sexes. In addition, it remains unclear how transient windows of central OTR signaling during sociosexual interaction modulate neural activity to produce enduring shifts in sociobehavioral phenotypes, including the formation of selective social bonds. Here we re-examine the role of the central OT system in partner preference formation in male prairie voles using a selective OTR antagonist delivered intracranially. We then use the same antagonist to examine how central OTRs modulate behavior and immediate early gene (Fos) expression, a metric of neuronal activation, in males during brief sociosexual interaction with a female. Our results suggest that, as in females, OTR signaling is critical for partner preference formation in males and enhances correlated activation across sensory and reward processing brain areas during sociosexual interaction. These results are consistent with the hypothesis that central OTR signaling facilitates social bond formation by coordinating activity across a pair bonding neural network. PMID:26643557

  10. Central oxytocin receptors mediate mating-induced partner preferences and enhance correlated activation across forebrain nuclei in male prairie voles.

    PubMed

    Johnson, Zachary V; Walum, Hasse; Jamal, Yaseen A; Xiao, Yao; Keebaugh, Alaine C; Inoue, Kiyoshi; Young, Larry J

    2016-03-01

    Oxytocin (OT) is a deeply conserved nonapeptide that acts both peripherally and centrally to modulate reproductive physiology and sociosexual behavior across divergent taxa, including humans. In vertebrates, the distribution of the oxytocin receptor (OTR) in the brain is variable within and across species, and OTR signaling is critical for a variety of species-typical social and reproductive behaviors, including affiliative and pair bonding behaviors in multiple socially monogamous lineages of fishes, birds, and mammals. Early work in prairie voles suggested that the endogenous OT system modulates mating-induced partner preference formation in females but not males; however, there is significant evidence that central OTRs may modulate pair bonding behavior in both sexes. In addition, it remains unclear how transient windows of central OTR signaling during sociosexual interaction modulate neural activity to produce enduring shifts in sociobehavioral phenotypes, including the formation of selective social bonds. Here we re-examine the role of the central OT system in partner preference formation in male prairie voles using a selective OTR antagonist delivered intracranially. We then use the same antagonist to examine how central OTRs modulate behavior and immediate early gene (Fos) expression, a metric of neuronal activation, in males during brief sociosexual interaction with a female. Our results suggest that, as in females, OTR signaling is critical for partner preference formation in males and enhances correlated activation across sensory and reward processing brain areas during sociosexual interaction. These results are consistent with the hypothesis that central OTR signaling facilitates social bond formation by coordinating activity across a pair bonding n