Effectiveness of calcium hypochlorite on viral and bacterial contamination of alfalfa seeds.

PubMed

Wang, Qing; Kniel, Kalmia E

2014-10-01

Alfalfa sprouts have been involved in numerous foodborne outbreaks, which has increased the awareness for seed and sprout safety. This study compared the effectiveness of calcium hypochlorite (Ca(OCl)2) on the inactivation of bacteria and viruses on alfalfa seeds and in the presence of a simulated organic load. Alfalfa seeds were inoculated with human norovirus (huNoV) genogroup II (GII), murine norovirus (MNV), Tulane virus (TV), Escherichia coli O104:H4, and Salmonella enterica serovar Agona. Seeds were treated with Ca(OCl)2 (2000 ppm or 20,000 ppm with the average of free chlorine 1388 ± 117 mg/L and 11,472 ± 1500 mg/L, respectively, pH adjusted to 7.00). The reduction of huNoV genomic copies indicated that huNoV was relatively resistant to Ca(OCl)2 regardless of concentrations. Significant reductions were observed in the order of TV < Salmonella Agona < MNV < E. coli O104:H4 at 20,000 ppm Ca(OCl)2. A similar trend was found at 2000 ppm Ca(OCl)2 in the order of TV, Salmonella Agona, MNV < E. coli O104:H4. Ca(OCl)2 at 20,000 ppm was more effective than 2000 ppm for all the organisms tested. This trend was also observed in samples containing an artificial organic material load. Ca(OCl)2 activity on virus inactivation decreased as the organic load increased. Reduction was greater in fetal bovine serum-containing samples compared to alfalfa seeds, indicating a close relationship between the organisms and alfalfa seeds. Ca(OCl)2 could not completely inactivate bacteria or viruses inoculated on seeds, and high levels of E. coli O104:H4 and Salmonella Agona were present on sprouts from sanitized seed samples following a 7-day germination period.

Advanced Residual Strength Degradation Rate Modeling for Advanced Composite Structures. Volume II. Tasks II and III.

DTIC Science & Technology

1981-07-01

ADVANCED COMPOSITE STRUCTURES VOLUME II - TASKS Ix AND III K. N. Lauraitis Tl J. T. Ryder ?l4 D. E. Pettit ~ Lockheed-California Company S Burbank...Strength Degradation Rate Final Report Modeling for Advanced Composite Structures 1 July 1979 to 29 May 1981 Vol II - Task II and III S. PERFORMIN ONG...identify by block namber) composites , graphite/epoxy, impact damage, damaged holes, fatigue, damage propagation, residual strength, NDI 20. ABSTRACT

AmeriFlux US-Tw3 Twitchell Alfalfa

DOE Data Explorer

Baldocchi, Dennis [University of California, Berkeley

2016-01-01

This is the AmeriFlux version of the carbon flux data for the site US-Tw3 Twitchell Alfalfa. Site Description - The Twitchell Alfalfa site is an alfalfa field owned by the state of California and leased to third parties for farming. The tower was installed on May 24, 2013. This site and the surrounding region are part of the San Joaquin - Sacramento River Delta drained beginning in the 1850's and subsequently used for agriculture. The field has been alfalfa for X years…., Crop rotation occurs every 5-6 years. The site is harvested by mowing and bailing several times per year. The field is fallow typically between November and February. The site is irrigated by periodically-flooded ditches surrounding the field. The site is irrigated by raising, and subsequently lowering the water table??

Allelopathic effect of alfalfa (Medicago sativa) on bladygrass (Imperata cylindrica).

PubMed

Abdul-Rahman, A A; Habib, S A

1989-09-01

Greenhouse and laboratory experiments were conducted at the Agricultural and Water Resources Research Center Station, Baghdad, in 1985 and 1986 to investigate the possible allelopathic potential of alfalfa (Medicago saliva L.) and its decomposed residues on bladygrass (Imperata cylin-drica L. Beauv.), a noxious weed in Iraq, and to isolate, characterize, and quantify possible allelopathic agents in alfalfa residues and root exudates. Results indicated that decomposed alfalfa roots and their associated soil produced a 51-56% reduction in bladygrass seed germination. Root and shoot length of bladygrass seedlings were reduced by an average of 88%. Decayed and undecayed mixtures of alfalfa roots and soil at 0.015∶1 (w/w) inhibited bladygrass seedlings reproduced from rhizomes by 30 and 42%. It was found that root exudates of alfalfa seedlings caused significant reduction in shoot and root dry weights of bladygrass seedlings when alfalfa and bladygrass were grown together in nutrient culture. Caffeic, chlorogenic, isochloro-genic,p-coumaric,p-OH-benzoic, and ferulic acids were detected in alfalfa root exudates and residues. The highest amount (126 fig phenolic acids/g soil) of these compounds was found in alfalfa root residues after six months of decomposition in soil.

Redesigning alfalfa to reduce protein losses

USDA-ARS?s Scientific Manuscript database

Alfalfa is often referred to as the “Queen of Forages” due to its relatively good digestibility, high protein, and ability to readily fix nitrogen. But there’s a big drawback to alfalfa – much of its protein is lost during the harvest and ensiling process, and more is lost in the rumen of livestock....

Alfalfa seed germination and yield ratio and alfalfa sprout microbial keeping quality following irradiation of seeds and sprouts.

PubMed

Rajkowski, K T; Thayer, D W

2001-12-01

Foods can be treated with gamma radiation, a nonthermal food process, to inactivate foodborne pathogens and fungi, to kill insects on or in fruits and vegetables, and to increase shelf life. Gamma irradiation is especially well suited for these treatments because of its ability to penetrate commercial pallets of foods. Irradiated fruits, vegetables, poultry, and hamburger have been received favorably by the public and are now available in supermarkets. The use of irradiation on fresh alfalfa sprouts was studied to determine its effect on keeping quality as related to aerobic microbial load. After an irradiation dose of 2 kGy, the total aerobic count decreased from 10(5-8) to 10(3-5) CFU/g, and the total coliform counts decreased from 10(5-8) to 10(3-0) CFU/g. The results showed that the sprouts maintained their structure after irradiation, and the keeping quality was extended to 21 days, which is an increase of 10 days from the usual shelf life. The effect of various doses of irradiation on alfalfa seeds as measured by percent germination and yield ratio (wt/wt) of sprouts was determined. There was little effect on the percent germination, but as the dose increased, the yield ratio of alfalfa sprouts decreased. As the length of growing time increased, so did the yield ratio of the lower dose irradiated seeds (1 to 2 kGy). The irradiation process can be used to increase the shelf life of alfalfa sprouts, and irradiating alfalfa seeds at doses up to 2 kGy does not unacceptably decrease the yield ratio for production of alfalfa sprouts.

Broadening the U.S. alfalfa germplasm base

USDA-ARS?s Scientific Manuscript database

Over 4000 alfalfa (Medicago sativa L.) plant introductions (PIs) exist in the USDA-ARS National Plant Germplasm System (NPGS). NAAIC has discussed/proposed pre-breeding efforts to utilize this germplasm for creating pre-commercial alfalfa germplasm. Funding constraints have been one impediment to th...

Lessons learned in managing alfalfa-grass mixtures

USDA-ARS?s Scientific Manuscript database

Grass-alfalfa mixtures have a number of benefits that make them attractive to producers. However, they can be problematic to establish and maintain. Research programs have made progress in understanding the benefits and challenges of alfalfa-grass mixtures. Mixtures may have greater winter survival ...

Occurrence of transgenic feral alfalfa (Medicago sativa subsp. sativa L.) in alfalfa seed production areas in the United States

USDA-ARS?s Scientific Manuscript database

Genetically-engineered glyphosate-resistant alfalfa (Medicago sativa subsp. sativa) was commercialized in 2011. The potential risk of transgene dispersal into the environment is not clearly understood for alfalfa, a perennial crop that is cross-pollinated by insects. We gathered data on feral and tr...

Relationship of crop radiance to alfalfa agronomic values

NASA Technical Reports Server (NTRS)

Tucker, C. J.; Elgin, J. H., Jr.; Mcmurtrey, J. E., III

1980-01-01

Red and photographic infrared spectral data of alfalfa were collected at the time of the third and fourth cuttings using a hand-held radiometer for the earlier alfalfa cutting. Significant linear and non-linear correlation coefficients were found between the spectral variables and plant height, biomass, forage water content, and estimated canopy cover. For the alfalfa of the later cutting, which had experienced a period of severe drought stress which limited growth, the spectral variables were found to be highly correlated with the estimated drought scores.

Aviation Pilot Training II. Task Analyses: [Year II.] Field Review Copy.

ERIC Educational Resources Information Center

Upchurch, Richard

This guide for aviation pilot II training begins with a course description, resource information, and a course outline. Tasks/competencies are categorized into 10 concept/duty areas: understanding aircraft staffs and procedures for safe recovery; understanding procedures for constant altitude turns; understanding procedures for traffic pattern…

Occurrence of Transgenic Feral Alfalfa (Medicago sativa subsp. sativa L.) in Alfalfa Seed Production Areas in the United States.

PubMed

Greene, Stephanie L; Kesoju, Sandya R; Martin, Ruth C; Kramer, Matthew

2015-01-01

The potential environmental risks of transgene exposure are not clear for alfalfa (Medicago sativa subsp. sativa), a perennial crop that is cross-pollinated by insects. We gathered data on feral alfalfa in major alfalfa seed-production areas in the western United States to (1) evaluate evidence that feral transgenic plants spread transgenes and (2) determine environmental and agricultural production factors influencing the location of feral alfalfa, especially transgenic plants. Road verges in Fresno, California; Canyon, Idaho; and Walla Walla, Washington were surveyed in 2011 and 2012 for feral plants, and samples were tested for the CP4 EPSPS protein that conveys resistance to glyphosate. Of 4580 sites surveyed, feral plants were observed at 404 sites. Twenty-seven percent of these sites had transgenic plants. The frequency of sites having transgenic feral plants varied among our study areas. Transgenic plants were found in 32.7%, 21.4.7% and 8.3% of feral plant sites in Fresno, Canyon and Walla Walla, respectively. Spatial analysis suggested that feral populations started independently and tended to cluster in seed and hay production areas, places where seed tended to drop. Significant but low spatial auto correlation suggested that in some instances, plants colonized nearby locations. Neighboring feral plants were frequently within pollinator foraging range; however, further research is needed to confirm transgene flow. Locations of feral plant clusters were not well predicted by environmental and production variables. However, the likelihood of seed spillage during production and transport had predictive value in explaining the occurrence of transgenic feral populations. Our study confirms that genetically engineered alfalfa has dispersed into the environment, and suggests that minimizing seed spillage and eradicating feral alfalfa along road sides would be effective strategies to minimize transgene dispersal.

Occurrence of Transgenic Feral Alfalfa (Medicago sativa subsp. sativa L.) in Alfalfa Seed Production Areas in the United States

PubMed Central

Greene, Stephanie L.; Kesoju, Sandya R.; Martin, Ruth C.; Kramer, Matthew

2015-01-01

The potential environmental risks of transgene exposure are not clear for alfalfa (Medicago sativa subsp. sativa), a perennial crop that is cross-pollinated by insects. We gathered data on feral alfalfa in major alfalfa seed-production areas in the western United States to (1) evaluate evidence that feral transgenic plants spread transgenes and (2) determine environmental and agricultural production factors influencing the location of feral alfalfa, especially transgenic plants. Road verges in Fresno, California; Canyon, Idaho; and Walla Walla, Washington were surveyed in 2011 and 2012 for feral plants, and samples were tested for the CP4 EPSPS protein that conveys resistance to glyphosate. Of 4580 sites surveyed, feral plants were observed at 404 sites. Twenty-seven percent of these sites had transgenic plants. The frequency of sites having transgenic feral plants varied among our study areas. Transgenic plants were found in 32.7%, 21.4.7% and 8.3% of feral plant sites in Fresno, Canyon and Walla Walla, respectively. Spatial analysis suggested that feral populations started independently and tended to cluster in seed and hay production areas, places where seed tended to drop. Significant but low spatial auto correlation suggested that in some instances, plants colonized nearby locations. Neighboring feral plants were frequently within pollinator foraging range; however, further research is needed to confirm transgene flow. Locations of feral plant clusters were not well predicted by environmental and production variables. However, the likelihood of seed spillage during production and transport had predictive value in explaining the occurrence of transgenic feral populations. Our study confirms that genetically engineered alfalfa has dispersed into the environment, and suggests that minimizing seed spillage and eradicating feral alfalfa along road sides would be effective strategies to minimize transgene dispersal. PMID:26699337

Alfalfa Biomass Germplasms: SFP Detection and Transcriptome Analysis

USDA-ARS?s Scientific Manuscript database

Advances in alfalfa [Medicago sativa (L.) subsp. sativa] breeding, molecular genetics, and genomics have been slow because this crop is an allogamous autotetraploid (2n = 4x = 32) with complex polysomic inheritance. Increasing cellulose and decreasing lignin in alfalfa stem cell walls would improve ...

Alfalfa production with subsurface drip irrigation in the Central Great Plains

USDA-ARS?s Scientific Manuscript database

Irrigated alfalfa production is gaining interest because of the growing number of dairies in the semi-arid U.S. Central Great Plains and its longstanding superior profitability compared to other alternative crops grown in the region. Irrigation requirements for alfalfa are great because of alfalfa's...

Solid-substrate fermentation of alfalfa for enhanced protein recovery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bajracharya, R.; Madgett, R.E.

1979-04-01

Solid-substrate fermentations for extraction of protein from pressed alfalfa residues with Aspergillus Sp. QM 9994, Aspergillus niger QM 877, and Rhizopus nigricans QM 387 were conducted in shake flasks. Upon reimbibing and second pressing, total protein recovery from alfalfa was increased from 47.2% for control samples and up to 64.5% for fermented samples. Analysis of juice from fermented samples indicated the presence of cellulase as well as pectinase activities. Dialysis cultures of cellulase-producing fungi showed that total biomass production and solids consumption were much higher than those of a mutant strain lacking the ability to produce cellulase, indicating significant utilizationmore » of cellulosic materials in alfalfa. The biomass yields in the former case ranged from 39-47% based on total solids consumption. Since some of the cellulosic and other carbohydrate constituents in alfalfa may be converted into fungal protein, final alfalfa residues following protein extraction in a commercial process would be less bulky for storage and handling and would be more digestible as a nonruminant animal feed.« less

Allelopathic interference of alfalfa (Medicago sativa L.) genotypes to annual ryegrass (Lolium rigidum).

PubMed

Zubair, Hasan Muhammad; Pratley, James E; Sandral, G A; Humphries, A

2017-07-01

Alfalfa (Medicago sativa L.) genotypes at varying densities were investigated for allelopathic impact using annual ryegrass (Lolium rigidum) as the target species in a laboratory bioassay. Three densities (15, 30, and 50 seedlings/beaker) and 40 alfalfa genotypes were evaluated by the equal compartment agar method (ECAM). Alfalfa genotypes displayed a range of allelopathic interference in ryegrass seedlings, reducing root length from 5 to 65%. The growth of ryegrass decreased in response to increasing density of alfalfa seedlings. At the lowest density, Q75 and Titan9 were the least allelopathic genotypes. An overall inhibition index was calculated to rank each alfalfa genotype. Reduction in seed germination of annual ryegrass occurred in the presence of several alfalfa genotypes including Force 10, Haymaster7 and SARDI Five. A comprehensive metabolomic analysis using Quadruple Time of Flight (Q-TOF), was conducted to compare six alfalfa genotypes. Variation in chemical compounds was found between alfalfa root extracts and exudates and also between genotypes. Further individual compound assessments and quantitative study at greater chemical concentrations are needed to clarify the allelopathic activity. Considerable genetic variation exists among alfalfa genotypes for allelopathic activity creating the opportunity for its use in weed suppression through selection.

Molecular basis of protein structure in proanthocyanidin and anthocyanin-enhanced Lc-transgenic alfalfa in relation to nutritive value using synchrotron-radiation FTIR microspectroscopy: A novel approach

NASA Astrophysics Data System (ADS)

Yu, Peiqiang; Jonker, Arjan; Gruber, Margaret

2009-09-01

24) and amide II areas (average of 10) and their ratio (average of 2.4) compared with non-transgenic alfalfa. Cluster analysis and principal component analysis showed no significant differences between the two genotypes in the broad molecular fingerprint region, amides I and II regions, and the carbohydrate molecular region, indicating they are highly related to each other. The results suggest that transgenic Lc-alfalfa leaves contain similar proteins to non-transgenic alfalfa (because amide I and II intensities were identical), but a subtle difference in protein molecular structure after freeze drying. Further study is needed to understand the relationship between these structural profiles and biological features such as protein nutrient availability, protein bypass and digestive behavior of livestock fed with this type of forage.

Transgene movement in commercial alfalfa seed production: Implications for seed purity

USDA-ARS?s Scientific Manuscript database

The United States is a major exporter of alfalfa seed and hay and the organic dairy industry is one of the fastest growing agricultural sectors. With the advent of genetically-engineered (GE) alfalfa concerns have risen regarding the coexistence of GE and non GE alfalfa since the crop is largely ou...

Effects of alfalfa meal on carcase quality and fat metabolism of Muscovy ducks.

PubMed

Jiang, J F; Song, X M; Huang, X; Wu, J L; Zhou, W D; Zheng, H C; Jiang, Y Q

2012-01-01

1. The effects of alfalfa meal on carcase quality and fat metabolism of Muscovy duck were evaluated. The objective of this research was to establish whether alfalfa meal can reduce fat content and improve carcase quality of Muscovy duck. Animal products with a high fat content present a risk factor for many diseases. Reducing fat content in poultry products is an important goal for the poultry industry. 2. A total of 240 14-d-old white Muscovy ducks were selected and randomly allocated to 1 of 4 dietary treatments containing 0, 3, 6, and 9% of alfalfa meal for 5 weeks. Growth performances were recorded and carcase characteristics and lipid parameters were analysed. 3. Results showed that 3, 6, and 9% alfalfa meal in diet had no significant effects on growth performance of Muscovy ducks from 14 to 49 d of age. Ducks given 3, 6, and 9% alfalfa meal had significantly higher dressing percentage and lower abdominal fat percentage compared with those given no alfalfa meal. Ducks given 9% alfalfa meal had higher breast meat percentage compared with those given no alfalfa meal. The concentrations of triglyceride, total cholesterol, low density lipoprotein (LDL), very low density lipoprotein (VLDL) and free fatty acid in serum of ducks fed on alfalfa meal decreased. Alfalfa meal in the diet decreased abdominal fat percentage and improved carcase traits of Muscovy duck. 4. The study showed that dietary alfalfa meal decreased abdominal fat percentage and improved carcase traits, without an adverse effect on performance.

The Undergraduate ALFALFA Team: Collaborative Research Projects

NASA Astrophysics Data System (ADS)

Cannon, John M.; Koopmann, Rebecca A.; Haynes, Martha P.; Undergraduate ALFALFA Team, ALFALFA Team

2016-01-01

The NSF-sponsored Undergraduate ALFALFA (Arecibo Legacy Fast ALFA) Team (UAT) has allowed faculty and students from a wide range of public and private colleges and especially those with small astronomy programs to learn how science is accomplished in a large collaboration while contributing to the scientific goals of a legacy radio astronomy survey. The UAT has achieved this through close collaboration with ALFALFA PIs to identify research areas accessible to undergraduates. In this talk we will summarize the main research efforts of the UAT, including multiwavelength followup observations of ALFALFA sources, the UAT Collaborative Groups Project, the Survey of HI in Extremely Low-mass Dwarfs (SHIELD), and the Arecibo Pisces-Perseus Supercluster Survey. This work has been supported by NSF grants AST-0724918/0902211, AST-075267/0903394, AST-0725380, and AST-1211005.

Modelling the dynamics of feral alfalfa populations and its management implications.

PubMed

Bagavathiannan, Muthukumar V; Begg, Graham S; Gulden, Robert H; Van Acker, Rene C

2012-01-01

Feral populations of cultivated crops can pose challenges to novel trait confinement within agricultural landscapes. Simulation models can be helpful in investigating the underlying dynamics of feral populations and determining suitable management options. We developed a stage-structured matrix population model for roadside feral alfalfa populations occurring in southern Manitoba, Canada. The model accounted for the existence of density-dependence and recruitment subsidy in feral populations. We used the model to investigate the long-term dynamics of feral alfalfa populations, and to evaluate the effectiveness of simulated management strategies such as herbicide application and mowing in controlling feral alfalfa. Results suggest that alfalfa populations occurring in roadside habitats can be persistent and less likely to go extinct under current roadverge management scenarios. Management attempts focused on controlling adult plants alone can be counterproductive due to the presence of density-dependent effects. Targeted herbicide application, which can achieve complete control of seedlings, rosettes and established plants, will be an effective strategy, but the seedbank population may contribute to new recruits. In regions where roadside mowing is regularly practiced, devising a timely mowing strategy (early- to mid-August for southern Manitoba), one that can totally prevent seed production, will be a feasible option for managing feral alfalfa populations. Feral alfalfa populations can be persistent in roadside habitats. Timely mowing or regular targeted herbicide application will be effective in managing feral alfalfa populations and limit feral-population-mediated gene flow in alfalfa. However, in the context of novel trait confinement, the extent to which feral alfalfa populations need to be managed will be dictated by the tolerance levels established by specific production systems for specific traits. The modelling framework outlined in this paper could be

Agricultural Science and Mechanics I & II. Task Analyses. Competency-Based Education.

ERIC Educational Resources Information Center

Henrico County Public Schools, Glen Allen, VA. Virginia Vocational Curriculum Center.

This task analysis guide is intended to help teachers and administrators develop instructional materials and implement competency-based education in the agricultural science and mechanics courses. Section 1 contains a validated task inventory for agricultural science and mechanics I and II. For each task, applicable information pertaining to…

The Use of Gene Modification and Advanced Molecular Structure Analyses towards Improving Alfalfa Forage.

PubMed

Lei, Yaogeng; Hannoufa, Abdelali; Yu, Peiqiang

2017-01-29

Alfalfa is one of the most important legume forage crops in the world. In spite of its agronomic and nutritive advantages, alfalfa has some limitations in the usage of pasture forage and hay supplement. High rapid degradation of protein in alfalfa poses a risk of rumen bloat to ruminants which could cause huge economic losses for farmers. Coupled with the relatively high lignin content, which impedes the degradation of carbohydrate in rumen, alfalfa has unbalanced and asynchronous degradation ratio of nitrogen to carbohydrate (N/CHO) in rumen. Genetic engineering approaches have been used to manipulate the expression of genes involved in important metabolic pathways for the purpose of improving the nutritive value, forage yield, and the ability to resist abiotic stress. Such gene modification could bring molecular structural changes in alfalfa that are detectable by advanced structural analytical techniques. These structural analyses have been employed in assessing alfalfa forage characteristics, allowing for rapid, convenient and cost-effective analysis of alfalfa forage quality. In this article, we review two major obstacles facing alfalfa utilization, namely poor protein utilization and relatively high lignin content, and highlight genetic studies that were performed to overcome these drawbacks, as well as to introduce other improvements to alfalfa quality. We also review the use of advanced molecular structural analysis in the assessment of alfalfa forage for its potential usage in quality selection in alfalfa breeding.

The Use of Gene Modification and Advanced Molecular Structure Analyses towards Improving Alfalfa Forage

PubMed Central

Lei, Yaogeng; Hannoufa, Abdelali; Yu, Peiqiang

2017-01-01

Alfalfa is one of the most important legume forage crops in the world. In spite of its agronomic and nutritive advantages, alfalfa has some limitations in the usage of pasture forage and hay supplement. High rapid degradation of protein in alfalfa poses a risk of rumen bloat to ruminants which could cause huge economic losses for farmers. Coupled with the relatively high lignin content, which impedes the degradation of carbohydrate in rumen, alfalfa has unbalanced and asynchronous degradation ratio of nitrogen to carbohydrate (N/CHO) in rumen. Genetic engineering approaches have been used to manipulate the expression of genes involved in important metabolic pathways for the purpose of improving the nutritive value, forage yield, and the ability to resist abiotic stress. Such gene modification could bring molecular structural changes in alfalfa that are detectable by advanced structural analytical techniques. These structural analyses have been employed in assessing alfalfa forage characteristics, allowing for rapid, convenient and cost-effective analysis of alfalfa forage quality. In this article, we review two major obstacles facing alfalfa utilization, namely poor protein utilization and relatively high lignin content, and highlight genetic studies that were performed to overcome these drawbacks, as well as to introduce other improvements to alfalfa quality. We also review the use of advanced molecular structural analysis in the assessment of alfalfa forage for its potential usage in quality selection in alfalfa breeding. PMID:28146083

[Population dynamics of ground carabid beetles and spiders in a wheat field along the wheat-alfalfa interface and their response to alfalfa mowing].

PubMed

Liu, Wen-Hui; Hu, Yi-Jun; Hu, Wen-Chao; Hong, Bo; Guan, Xiao-Qing; Ma, Shi-Yu; He, Da-Han

2014-09-01

Taking the wheat-alfalfa and wheat-wheat interfaces as model systems, sampling points were set by the method of pitfall trapping in the wheat field at the distances of 3 m, 6 m, 9 m, 12 m, 15 m, 18 m, 21 m, 24 m, and 27 m from the interface. The species composition and abundance of ground carabid beetles and spiders captured in pitfalls were investigated. The results showed that, to some extent there was an edge effect on species diversity and abundance of ground carabid beetles and spiders along the two interfaces. A marked edge effect was observed between 15 m and 18 m along the alfalfa-wheat interface, while no edge effect was found at a distance over 20 m. The edge effect along the wheat-wheat interface was weaker in comparison to the alfalfa-wheat interface. Alfalfa mowing resulted in the migration of a large number of ground carabid beetles and spiders to the adjacent wheat filed. During ten days since mowing, both species and abundance of ground carabid beetles and spiders increased in wheat filed within the distance of 20 m along the alfalfa-wheat interface. The spatial distribution of species diversity of ground beetles and spiders, together with the population abundance of the dominant Chlaenius pallipes and Pardosa astrigera, were depicted, which could directly indicate the migrating process of natural enemy from alfalfa to wheat field.

Aphanomyces root rot of alfalfa: Widespread distribution of race 2 in Minnesota

USDA-ARS?s Scientific Manuscript database

Strong seedling establishment in alfalfa is important to achieve the plant density needed to out-compete weeds and produce high biomass yields. Establishing alfalfa can be challenging because alfalfa seeds and seedlings are vulnerable to several pathogens present in soil. Wet soil conditions favor t...

The Use of Gene Modification and Advanced Molecular Structure Analyses towards Improving Alfalfa Forage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lei, Yaogeng; Hannoufa, Abdelali; Yu, Peiqiang

Alfalfa is one of the most important legume forage crops in the world. In spite of its agronomic and nutritive advantages, alfalfa has some limitations in the usage of pasture forage and hay supplement. High rapid degradation of protein in alfalfa poses a risk of rumen bloat to ruminants which could cause huge economic losses for farmers. Coupled with the relatively high lignin content, which impedes the degradation of carbohydrate in rumen, alfalfa has unbalanced and asynchronous degradation ratio of nitrogen to carbohydrate (N/CHO) in rumen. Genetic engineering approaches have been used to manipulate the expression of genes involved inmore » important metabolic pathways for the purpose of improving the nutritive value, forage yield, and the ability to resist abiotic stress. Such gene modification could bring molecular structural changes in alfalfa that are detectable by advanced structural analytical techniques. These structural analyses have been employed in assessing alfalfa forage characteristics, allowing for rapid, convenient and cost-effective analysis of alfalfa forage quality. In this article, we review two major obstacles facing alfalfa utilization, namely poor protein utilization and relatively high lignin content, and highlight genetic studies that were performed to overcome these drawbacks, as well as to introduce other improvements to alfalfa quality. We also review the use of advanced molecular structural analysis in the assessment of alfalfa forage for its potential usage in quality selection in alfalfa breeding.« less

Phytotoxicity of water-soluble substances from alfalfa and barley soil extracts on four crop species.

PubMed

Read, J J; Jensen, E H

1989-02-01

Problems associated with continuously planting alfalfa (Medicago saliva L.) or seeding to thicken depleted alfalfa stands may be due to autotoxicity, an intraspecific form of allelopathy. A bioassay approach was utilized to characterize the specificity and chemical nature of phytotoxins in extracts of alfalfa soils as compared to fallow soil or soil where a cereal was the previous crop. In germination chamber experiments, water-soluble substances present in methanol extracts of soil cropped to alfalfa or barley (Hordeum vulgare L.) decreased seedling root length of alfalfa L-720, winter wheat (Triticum aestivum L. Nugaines) and radish (Raphanus sativa L. Crimson Giant). Five days after germination, seedling dry weights of alfalfa and radish in alfalfa soil extracts were lower compared to wheat or red clover (Trifolium pralense L. Kenland). Growth of red clover was not significantly reduced by soil extracts from cropped soil. Extracts of crop residue screened from soil cropped to alfalfa or barley significantly reduced seedling root length; extracts of alfalfa residue caused a greater inhibition of seedling dry weight than extracts of barely residue. A phytotoxic, unidentified substance present in extracts of crop residue screened from alfalfa soil, which inhibited seedling root length of alfalfa, was isolated by thin-layer chromatography (TLC). Residues from a soil cropped continuously to alfalfa for 10 years had the greatest phytotoxic activity.

PRN 2009-1: Establishment of Antimicrobial Exposure Assessment Task Force II

EPA Pesticide Factsheets

This PR notice announces the establishment of the Antimicrobial Exposure Assessment Task Force II, an industry-wide task force to develop mixer, loader, applicator and post-application exposure data for antimicrobial pesticides used in various settings.

Questioning the rule of thumb: can verbal tasks be administered during the CVLT-II delay interval?

PubMed

Williams, Bethany R; Donovick, Peter J

2008-09-01

In the manual for the California Verbal Learning Test - II (CVLT-II), the authors suggest that nonverbal, rather than verbal, tasks be administered during the delay interval between administrations of the Short- and Long-Delay Recall trials of this test. They contend that this method minimizes the retroactive interference produced by intervening tasks. The purpose of the current study was to compare the extent to which verbal and nonverbal intervening tasks produce retroactive interference on CVLT-II List A recall following the long-delay. Participants in the present study were 120 undergraduate students. All participants completed the CVLT-II, and were randomly assigned to a group in which they were administered either a verbal (WAIS-III Vocabulary or Peabody Picture Vocabulary Test - IIIB) or nonverbal (Raven's Standard Progressive Matrices or WAIS-III Block Design) intervening task during the long-delay interval of the CVLT-II. Statistical analyses revealed that regardless of the type of intervening task given, participants in all groups recalled the same number of words and produced a similar number of intrusions during the CVLT-II recall trials. This indicates that not all verbal tasks produce retroactive effects beyond those produced by nonverbal tasks.

Practices that support coexistence: A survey of Alfalfa growers

USDA-ARS?s Scientific Manuscript database

The alfalfa industry has worked hard to foster the coexistence of genetically-engineered (GE) and conventional alfalfa production by developing a set of best management practices that aim to limit adventitious-presence (AP) of GE traits in conventional seed. The general goal is to minimize transgene...

Over-Expression of Arabidopsis EDT1 Gene Confers Drought Tolerance in Alfalfa (Medicago sativa L.)

PubMed Central

Zheng, Guangshun; Fan, Cunying; Di, Shaokang; Wang, Xuemin; Xiang, Chengbin; Pang, Yongzhen

2017-01-01

Alfalfa (Medicago sativa L.) is an important legume forage crop with great economic value. However, as the growth of alfalfa is seriously affected by an inadequate supply of water, drought is probably the major abiotic environmental factor that most severely affects alfalfa production worldwide. In an effort to enhance alfalfa drought tolerance, we transformed the Arabidopsis Enhanced Drought Tolerance 1 (AtEDT1) gene into alfalfa via Agrobacterium-mediated transformation. Compared with wild type plants, drought stress treatment resulted in higher survival rates and biomass, but reduced water loss rates in the transgenic plants. Furthermore, transgenic alfalfa plants had increased stomatal size, but reduced stomatal density, and these stomatal changes contributed greatly to reduced water loss from leaves. Importantly, transgenic alfalfa plants exhibited larger root systems with larger root lengths, root weight, and root diameters than wild type plants. The transgenic alfalfa plants had reduced membrane permeability and malondialdehyde content, but higher soluble sugar and proline content, higher superoxide dismutase activity, higher chlorophyll content, enhanced expression of drought-responsive genes, as compared with wild type plants. Notably, transgenic alfalfa plants grew better in a 2-year field trial and showed enhanced growth performance with increased biomass yield. All of our morphological, physiological, and molecular analyses demonstrated that the ectopic expression of AtEDT1 improved growth and enhanced drought tolerance in alfalfa. Our study provides alfalfa germplasm for use in forage improvement programs, and may help to increase alfalfa production in arid lands. PMID:29326737

Over-Expression of Arabidopsis EDT1 Gene Confers Drought Tolerance in Alfalfa (Medicago sativa L.).

PubMed

Zheng, Guangshun; Fan, Cunying; Di, Shaokang; Wang, Xuemin; Xiang, Chengbin; Pang, Yongzhen

2017-01-01

Alfalfa ( Medicago sativa L.) is an important legume forage crop with great economic value. However, as the growth of alfalfa is seriously affected by an inadequate supply of water, drought is probably the major abiotic environmental factor that most severely affects alfalfa production worldwide. In an effort to enhance alfalfa drought tolerance, we transformed the Arabidopsis Enhanced Drought Tolerance 1 ( AtEDT1 ) gene into alfalfa via Agrobacterium -mediated transformation. Compared with wild type plants, drought stress treatment resulted in higher survival rates and biomass, but reduced water loss rates in the transgenic plants. Furthermore, transgenic alfalfa plants had increased stomatal size, but reduced stomatal density, and these stomatal changes contributed greatly to reduced water loss from leaves. Importantly, transgenic alfalfa plants exhibited larger root systems with larger root lengths, root weight, and root diameters than wild type plants. The transgenic alfalfa plants had reduced membrane permeability and malondialdehyde content, but higher soluble sugar and proline content, higher superoxide dismutase activity, higher chlorophyll content, enhanced expression of drought-responsive genes, as compared with wild type plants. Notably, transgenic alfalfa plants grew better in a 2-year field trial and showed enhanced growth performance with increased biomass yield. All of our morphological, physiological, and molecular analyses demonstrated that the ectopic expression of AtEDT1 improved growth and enhanced drought tolerance in alfalfa. Our study provides alfalfa germplasm for use in forage improvement programs, and may help to increase alfalfa production in arid lands.

Pollen and seed mediated gene flow in commercial alfalfa seed production fields

USDA-ARS?s Scientific Manuscript database

The potential for gene flow has been widely recognized since alfalfa is pollinated by bees. The Western US is a major exporter of alfalfa seed and hay and the organic dairy industry is one of the fastest growing agricultural sectors. Because of this, many alfalfa producers are impacted by market sen...

Molecular Basis of Protein Structure in Proanthocyanidin and Anthocyanin-Enhanced Lc-transgenic Alfalfa in Relation to Nutritive Value Using Synchrotron-Radiation FTIR Microspectroscopy: A Novel Approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, P.; Jonker, A; Gruber, M

2009-01-01

amide II areas (average of 10) and their ratio (average of 2.4) compared with non-transgenic alfalfa. Cluster analysis and principal component analysis showed no significant differences between the two genotypes in the broad molecular fingerprint region, amides I and II regions, and the carbohydrate molecular region, indicating they are highly related to each other. The results suggest that transgenic Lc-alfalfa leaves contain similar proteins to non-transgenic alfalfa (because amide I and II intensities were identical), but a subtle difference in protein molecular structure after freeze drying. Further study is needed to understand the relationship between these structural profiles and biological features such as protein nutrient availability, protein bypass and digestive behavior of livestock fed with this type of forage.« less

Detection of Norspermidine and Norspermine in Medicago sativa L. (Alfalfa) 1

PubMed Central

Rodriguez-Garay, Benjamin; Phillips, Gregory C.; Kuehn, Glenn D.

1989-01-01

Shoot meristem tissues of alfalfa, Medicago sativa L., were found by high performance liquid chromatography analyses to contain the uncommon polyamines, norspermidine and norspermine. The chemical structures of norspermidine and norspermine, purified from alfalfa, were confirmed by comparison of mass spectra with those from authentic standards. The discovery of norspermidine and norspermine in alfalfa implicates the presence of at least two biosynthetic enzymes, a polyamine oxidase and a previously uncharacterized aminopropyltransferase. PMID:16666576

Effects of alfalfa meal on the intestinal microbial diversity and immunity of growing ducks.

PubMed

Jiang, J F; Song, X M; Wu, J L; Jiang, Y Q

2014-12-01

This study was conducted to investigate the effects of alfalfa meal diets on the intestinal microbial diversity and immunity of growing egg-type ducks. A total of 128 healthy 7-week-old female egg-type Shaoxing ducks were selected and randomly assigned into four dietary treatments: 0%, 3%, 6% and 9% alfalfa meal for 8 weeks. Each treatment consisted of four replicates of eight ducks each. Polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) was used to characterize the microbiota. The results showed that the DGGE fingerprints of the V6-V8 fragments of the 16S rRNA from the caeca and faeces of ducks fed 3%, 6% and 9% alfalfa meal had significantly higher microbiota species richness than those fed 0% alfalfa meal (p < 0.05). The Shannon-Weiner index of the microbiota from the caeca and faeces of ducks fed 3%, 6% and 9% alfalfa meal was significantly higher than those fed 0% alfalfa meal (p < 0.05). Molecular analysis of the caecal and faecal DNA extracts showed that the alfalfa meal diet promotes the intestinal microbial diversity, as indicated by their higher species richness and Shannon-Weiner index. However, the groups did not significantly differ in terms of average daily gain, feed intake and gain-to-feed ratio (p > 0.05), and the 3-9% alfalfa meal did not affect the growth performance of the growing egg-type ducks. The proliferation of T and B lymphocytes was significantly greater (p < 0.05) in the groups supplemented with 3%, 6% and 9% of alfalfa meal than the unsupplemented control group, and alfalfa meal promoted the lymphocytes proliferation of the growing egg-type ducks. Dietary alfalfa meal supplementation increases intestinal microbial community diversity and improves of the immune response growing egg-type ducks. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

Assessing disease stress and modeling yield losses in alfalfa

NASA Astrophysics Data System (ADS)

Guan, Jie

Alfalfa is the most important forage crop in the U.S. and worldwide. Fungal foliar diseases are believed to cause significant yield losses in alfalfa, yet, little quantitative information exists regarding the amount of crop loss. Different fungicides and application frequencies were used as tools to generate a range of foliar disease intensities in Ames and Nashua, IA. Visual disease assessments (disease incidence, disease severity, and percentage defoliation) were obtained weekly for each alfalfa growth cycle (two to three growing cycles per season). Remote sensing assessments were performed using a hand-held, multispectral radiometer to measure the amount and quality of sunlight reflected from alfalfa canopies. Factors such as incident radiation, sun angle, sensor height, and leaf wetness were all found to significantly affect the percentage reflectance of sunlight reflected from alfalfa canopies. The precision of visual and remote sensing assessment methods was quantified. Precision was defined as the intra-rater repeatability and inter-rater reliability of assessment methods. F-tests, slopes, intercepts, and coefficients of determination (R2) were used to compare assessment methods for precision. Results showed that among the three visual disease assessment methods (disease incidence, disease severity, and percentage defoliation), percentage defoliation had the highest intra-rater repeatability and inter-rater reliability. Remote sensing assessment method had better precision than the percentage defoliation assessment method based upon higher intra-rater repeatability and inter-rater reliability. Significant linear relationships between canopy reflectance (810 nm), percentage defoliation and yield were detected using linear regression and percentage reflectance (810 nm) assessments were found to have a stronger relationship with yield than percentage defoliation assessments. There were also significant linear relationships between percentage defoliation, dry

Quality Evaluation of Biscuits Supplemented with Alfalfa Seed Flour

PubMed Central

Ullah, Fahim; Ahmad, Sajjad; Wahab, Said; Zeb, Alam; Khan Khattak, Mansoor; Khan, Saleem; Kang, Min

2016-01-01

The effect of alfalfa seed flour supplementation on the quality characteristics of refined wheat flour-based biscuits was studied. The proximate composition of refined wheat flour and alfalfa seed flour was determined. Refined wheat flour contained 12.43% moisture, 11.52% crude protein, 1.61% crude fat, 0.71% crude fiber, 1.43% ash and 70.83% nitrogen free extract, while alfalfa seed flour contained 5.79%, 29.49%, 12.71%, 5.53%, 4.80% and 41.73% moisture, crude protein, crude fat, crude fiber, ash and nitrogen free extract correspondingly. Alfalfa seed flour at 5%, 10%, 15% and 20% supplementation levels was incorporated in refined wheat flour to produce composite flour. The biscuits prepared were subjected to quality evaluation. Physical analysis of biscuits disclosed that supplementation of alfalfa seed flour decreased the width from 47.25 to 42 mm and the spread factor from 62.7 to 53.12, while it increased the thickness from 7.53 to 8.10 mm. Supplementation of refined wheat flour–based biscuits with alfalfa seed flour at different inclusion levels significantly (p < 0.05) increased the crude protein content from 10.19% to 15.30%, the crude fiber content from 0.73% to 1.62%, the crude fat content from 17.46% to 21.59% and the ash content from 1.37% to 1.92%, whereas it decreased the moisture content from 3.57% to 3.26% and the nitrogen free extract from 66.90% to 59.32%. The effect of supplementation on the mineral contents of biscuits was also significant (p < 0.05). Potassium, magnesium, calcium, iron and zinc contents increased from 105.30, 14.65, 43.91, 3.74 and 0.94 to 145.00, 26.64, 79.60, 7.93 and 1.60 mg/100 g, respectively. Sensory evaluation revealed that the quality score of biscuits in terms of color, taste, texture and overall acceptability decreased with increased supplementation. The present research work confirmed that a maximum of 10% alfalfa seed flour supplementation in refined wheat flour could produce acceptable biscuits with an

Alfalfa virus S, a new species in the family Alphaflexiviridae

USDA-ARS?s Scientific Manuscript database

A new species of the family Alphaflexiviridae provisionally named alfalfa virus S (AVS) was discovered in alfalfa samples originating from Sudan. A complete nucleotide sequence of the viral genome consisting of 8,349 nucleotides excluding the 3’ poly(A) tail was determined by high throughput sequenc...

Using RNA-Seq for gene identification, polymorphism detection and transcript profiling in two alfalfa genotypes with divergent cell wall composition in stems

PubMed Central

2011-01-01

Background Alfalfa, [Medicago sativa (L.) sativa], a widely-grown perennial forage has potential for development as a cellulosic ethanol feedstock. However, the genomics of alfalfa, a non-model species, is still in its infancy. The recent advent of RNA-Seq, a massively parallel sequencing method for transcriptome analysis, provides an opportunity to expand the identification of alfalfa genes and polymorphisms, and conduct in-depth transcript profiling. Results Cell walls in stems of alfalfa genotype 708 have higher cellulose and lower lignin concentrations compared to cell walls in stems of genotype 773. Using the Illumina GA-II platform, a total of 198,861,304 expression sequence tags (ESTs, 76 bp in length) were generated from cDNA libraries derived from elongating stem (ES) and post-elongation stem (PES) internodes of 708 and 773. In addition, 341,984 ESTs were generated from ES and PES internodes of genotype 773 using the GS FLX Titanium platform. The first alfalfa (Medicago sativa) gene index (MSGI 1.0) was assembled using the Sanger ESTs available from GenBank, the GS FLX Titanium EST sequences, and the de novo assembled Illumina sequences. MSGI 1.0 contains 124,025 unique sequences including 22,729 tentative consensus sequences (TCs), 22,315 singletons and 78,981 pseudo-singletons. We identified a total of 1,294 simple sequence repeats (SSR) among the sequences in MSGI 1.0. In addition, a total of 10,826 single nucleotide polymorphisms (SNPs) were predicted between the two genotypes. Out of 55 SNPs randomly selected for experimental validation, 47 (85%) were polymorphic between the two genotypes. We also identified numerous allelic variations within each genotype. Digital gene expression analysis identified numerous candidate genes that may play a role in stem development as well as candidate genes that may contribute to the differences in cell wall composition in stems of the two genotypes. Conclusions Our results demonstrate that RNA-Seq can be

Pythium species causing damping-off of alfalfa in Minnesota: Identification, pathogenicity and fungicide sensitivity

USDA-ARS?s Scientific Manuscript database

Damping-off and seed rot is an important disease of alfalfa, severely affecting stand establishment when conditions favor the disease. Globally, 15 Pythium species are reported to cause damping-off and seed rot of alfalfa, although surveys of species causing disease on alfalfa in Minnesota are lacki...

Effects of alfalfa and orchardgrass on digestion by dairy cows.

PubMed

Holden, L A; Glenn, B P; Erdman, R A; Potts, W E

1994-09-01

The effects of alfalfa and orchardgrass diets of similar NDF content on ruminal digestion and digesta kinetics as measured using radiolabeled herbage were evaluated in Holstein cows. Two dry and two lactating cows, fitted with ruminal and duodenal cannulas, were fed 12 times daily at restricted and ad libitum intakes, respectively, in a crossover design. Diets were 65:35 and 55:45 hay: concentrate in DM for alfalfa and orchardgrass, respectively, with approximately 19% CP and 42% NDF. The DMI by lactating cows was greater for the alfalfa diet than for the orchardgrass diet. Ruminal and apparent total tract digestibilities of NDF and ADF were less for cows consuming the alfalfa diet than for those on the orchardgrass diet. Particle size of ruminal digesta, based on specific activity from a ruminal pulse-dose of 14C-labeled alfalfa or orchardgrass, did not decrease consistently with time and was greater than fecal particle size, suggesting selective retention of large digesta particles before passage. Ruminal and total tract fractional passage rates of indigestible NDF, based on 14C-labeled forage, did not differ as a result of forage or lactation stage, but NDF gut fill was greater in lactating than in dry cows, indicating that changes in gut fill were related more to differences in intake than to passage rate.

Multiwalled carbon nanotubes in alfalfa and wheat: toxicology and uptake.

PubMed

Miralles, Pola; Johnson, Errin; Church, Tamara L; Harris, Andrew T

2012-12-07

Data on the bioavailability and toxicity of carbon nanotubes (CNTs) in the environment, and, in particular, on their interactions with vascular plants, are limited. We investigated the effects of industrial-grade multiwalled CNTs (75 wt% CNTs) and their impurities on alfalfa and wheat. Phytotoxicity assays were performed during both seed germination and seedling growth. The germinations of both species were tolerant of up to 2560 mg l(-1) CNTs, and root elongation was enhanced in alfalfa and wheat seedlings exposed to CNTs. Remarkably, catalyst impurities also enhanced root elongation in alfalfa seedlings as well as wheat germination. Thus the impurities, not solely the CNTs, impacted the plants. CNT internalization by plants was investigated using electron microscopy and two-dimensional Raman mapping. The latter showed that CNTs were adsorbed onto the root surfaces of alfalfa and wheat without significant uptake or translocation. Electron microscopy investigations of internalization were inconclusive owing to poor contrast, so Fe(3)O(4)-functionalized CNTs were prepared and studied using energy-filter mapping of Fe(3)O(4). CNTs bearing Fe(3)O(4) nanoparticles were detected in the epidermis of one wheat root tip only, suggesting that internalization was possible but unusual. Thus, alfalfa and wheat tolerated high concentrations of industrial-grade multiwalled CNTs, which adsorbed onto their roots but were rarely taken up.

Multiwalled carbon nanotubes in alfalfa and wheat: toxicology and uptake

PubMed Central

Miralles, Pola; Johnson, Errin; Church, Tamara L.; Harris, Andrew T.

2012-01-01

Data on the bioavailability and toxicity of carbon nanotubes (CNTs) in the environment, and, in particular, on their interactions with vascular plants, are limited. We investigated the effects of industrial-grade multiwalled CNTs (75 wt% CNTs) and their impurities on alfalfa and wheat. Phytotoxicity assays were performed during both seed germination and seedling growth. The germinations of both species were tolerant of up to 2560 mg l−1 CNTs, and root elongation was enhanced in alfalfa and wheat seedlings exposed to CNTs. Remarkably, catalyst impurities also enhanced root elongation in alfalfa seedlings as well as wheat germination. Thus the impurities, not solely the CNTs, impacted the plants. CNT internalization by plants was investigated using electron microscopy and two-dimensional Raman mapping. The latter showed that CNTs were adsorbed onto the root surfaces of alfalfa and wheat without significant uptake or translocation. Electron microscopy investigations of internalization were inconclusive owing to poor contrast, so Fe3O4-functionalized CNTs were prepared and studied using energy-filter mapping of Fe3O4. CNTs bearing Fe3O4 nanoparticles were detected in the epidermis of one wheat root tip only, suggesting that internalization was possible but unusual. Thus, alfalfa and wheat tolerated high concentrations of industrial-grade multiwalled CNTs, which adsorbed onto their roots but were rarely taken up. PMID:22977097

Roadside alfalfa: Innocent bystanders or conveyers of genetically-engineered traits?

USDA-ARS?s Scientific Manuscript database

Clumps of alfalfa are a common sight along roads and vacant lots in areas that grow alfalfa for hay or seed. So what role do feral roadside plants play in dispersing transgenes? Is there a risk that transgenic feral plants serve as reservoirs or conduits that might facilitate the movement of transg...

Modeling feral alfalfa (Medicago sativa subsp. sativa L.) occurrence using topographical and environmental variables

USDA-ARS?s Scientific Manuscript database

Because alfalfa is a perennial species cross pollinated by bees and can establish along roadsides and ruderal areas, there is concern that feral plants can serve as reservoirs and conduits for transgenic genes. The objective of this study was to survey feral alfalfa in alfalfa seed production areas ...

Dynamics of predation on Lygus hesperus (Hemiptera: Miridae) in alfalfa trap cropped organic strawberry

USDA-ARS?s Scientific Manuscript database

Alfalfa (Medicago sativa L.) can be strategically planted as a trap crop for Lygus spp. in California’s organic strawberry fields. Alfalfa has been shown to attract both Lygus spp. and, in turn, a Lygus-specific parasitoid, Peristenus relictus (Ruthe). However, the impact of alfalfa trap-cropped st...

Selenium and sulfur relationships in alfalfa and soil under field conditions, San Joaquin Valley, California

USGS Publications Warehouse

Severson, R.C.; Gough, L.P.

1992-01-01

Relationships between total Se and S or soluble SeO4 and SO4 in soils and tissue concentrations in alfalfa (Medicago sativa L.), under field conditions in the San Joaquin Valley of California, suggest that the rate of accumulation of Se in alfalfa may be reduced in areas where high Se and S concentrations in soils were measured. These data suggest that the balance between carbonate and sulfate minerals in soil may have a greater influence on uptake of Se by alfalfa than does the balance of SeO4 and SO4 in soil solution. Soil and alfalfa were sampled from areas representing a wide range in soil Se and S concentrations. Specific sampling locations were selected based on a previous study of Se, S, and other elements where 721 soil samples were collected to map landscape variability and distribution of elements. Six multiple-linear regression equations were developed between total and/or soluble soil chemical constituents and tissue concentrations of Se in alfalfa. We chose a regression model that accounted for 72% of the variability in alfalfa Se concentrations based on an association of elements in soil (total C, S, Se, and Sr) determined by factor analysis. To prepare a map showing the spatial distribution of estimated alfalfa Se concentrations, the model was applied to the data from the previously collected 721 soil samples. Estimated alfalfa Se concentrations in most of the study area were within a range that is predicted to produce alfalfa with neither Se deficiency nor toxicity when consumed by livestock. A few small areas are predicted to produce alfalfa that potentially would not meet minimum dietary needs of livestock.

Evaluation of DCS III Transmission Alternatives, Phase II, Task 1.

DTIC Science & Technology

1981-08-31

Agency Defense Communications Engineering Center Reston, Virginia 22090 Contract No. DCA 100-79-C--0044 ,D ii 2 01982 ONG SPACI IAE K ROONOO IIACH...Transmission Media Alternatives Task 2. Development of Evolving DCS Transmission System Al ternatives Task 3. Identification of Technology and Regulatory...For existing tree growth, add 15 m. For smaller vegetation, add 3 m. 11. Determine the antenna tower heights to insure line-of-sight clearance above the

Alfalfa (Medicago sativa L.) shoot saponins: identification and bio-activity by the assessment of aphid feeding.

PubMed

Mazahery-Laghab, H; Yazdi-Samadi, B; Bagheri, M; Bagheri, A R

2011-01-01

Biochemical components in alfalfa (Medicago sativa L.), such as saponins, can act as protecting factors against bio-stresses. Saponins are also antifeedants and show oral toxicity towards higher and lower animals. Changes in saponins, such as variation in the carbon skeleton, or hydrolysis of saponin glycosides and other conjugates, may change their biological effects. The aims of this research were to study saponin variation in different growth stages of alfalfa and to investigate the biological role of saponins in the spotted alfalfa aphid, Therioaphis maculata. Saponins from alfalfa shoots in different growth stages were extracted, chemically purified and analysed by TLC. Specific saponins such as soyasaponin1 from root and shoot and two bisdesmosides of medicagenic acid, one from shoot and another from root tissues, were identified using reference compounds allowing changes in saponin composition during plant development in different shoot tissues of alfalfa to be assessed. The response of the alfalfa aphid to feeding on alfalfa in different growth stages was studied. No significant difference in the survival of aphids, from neonate to adult, was observed, but due to the antibiotic effects of saponins, two differences were found in the onset of nymph production and cumulative nymph production. The results show that the saponin composition in alfalfa changes with plant development and this, in turn, can often negatively affect the development of specific insect pests such as the spotted alfalfa aphid, suggesting a possible biological role of alfalfa saponins.

Proteomic Identification of Differentially Expressed Proteins during Alfalfa (Medicago sativa L.) Flower Development.

PubMed

Chen, Lingling; Chen, Quanzhu; Zhu, Yanqiao; Hou, Longyu; Mao, Peisheng

2016-01-01

Flower development, pollination, and fertilization are important stages in the sexual reproduction process of plants; they are also critical steps in the control of seed formation and development. During alfalfa ( Medicago sativa L.) seed production, some distinct phenomena such as a low seed setting ratio, serious flower falling, and seed abortion commonly occur. However, the causes of these phenomena are complicated and largely unknown. An understanding of the mechanisms that regulate alfalfa flowering is important in order to increase seed yield. Hence, proteomic technology was used to analyze changes in protein expression during the stages of alfalfa flower development. Flower samples were collected at pre-pollination (S1), pollination (S2), and the post-pollination senescence period (S3). Twenty-four differentially expressed proteins were successfully identified, including 17 down-regulated in pollinated flowers, one up-regulated in pollinated and senesced flowers, and six up-regulated in senesced flowers. The largest proportions of the identified proteins were involved in metabolism, signal transduction, defense response, oxidation reduction, cell death, and programmed cell death (PCD). Their expression profiles demonstrated that energy metabolism, carbohydrate metabolism, and amino acid metabolism provided the nutrient foundation for pollination in alfalfa. Furthermore, there were three proteins involved in multiple metabolic pathways: dual specificity kinase splA-like protein (kinase splALs), carbonic anhydrase, and NADPH: quinone oxidoreductase-like protein. Expression patterns of these proteins indicated that MAPK cascades regulated multiple processes, such as signal transduction, stress response, and cell death. PCD also played an important role in the alfalfa flower developmental process, and regulated both pollination and flower senescence. The current study sheds some light on protein expression profiles during alfalfa flower development and

Proteomic Identification of Differentially Expressed Proteins during Alfalfa (Medicago sativa L.) Flower Development

PubMed Central

Chen, Lingling; Chen, Quanzhu; Zhu, Yanqiao; Hou, Longyu; Mao, Peisheng

2016-01-01

Flower development, pollination, and fertilization are important stages in the sexual reproduction process of plants; they are also critical steps in the control of seed formation and development. During alfalfa (Medicago sativa L.) seed production, some distinct phenomena such as a low seed setting ratio, serious flower falling, and seed abortion commonly occur. However, the causes of these phenomena are complicated and largely unknown. An understanding of the mechanisms that regulate alfalfa flowering is important in order to increase seed yield. Hence, proteomic technology was used to analyze changes in protein expression during the stages of alfalfa flower development. Flower samples were collected at pre-pollination (S1), pollination (S2), and the post-pollination senescence period (S3). Twenty-four differentially expressed proteins were successfully identified, including 17 down-regulated in pollinated flowers, one up-regulated in pollinated and senesced flowers, and six up-regulated in senesced flowers. The largest proportions of the identified proteins were involved in metabolism, signal transduction, defense response, oxidation reduction, cell death, and programmed cell death (PCD). Their expression profiles demonstrated that energy metabolism, carbohydrate metabolism, and amino acid metabolism provided the nutrient foundation for pollination in alfalfa. Furthermore, there were three proteins involved in multiple metabolic pathways: dual specificity kinase splA-like protein (kinase splALs), carbonic anhydrase, and NADPH: quinone oxidoreductase-like protein. Expression patterns of these proteins indicated that MAPK cascades regulated multiple processes, such as signal transduction, stress response, and cell death. PCD also played an important role in the alfalfa flower developmental process, and regulated both pollination and flower senescence. The current study sheds some light on protein expression profiles during alfalfa flower development and

Alfalfa transgene dispersal and adventitious presence: understanding grower perception of risk

USDA-ARS?s Scientific Manuscript database

Recognizing the importance of coexistence, the alfalfa industry has developed a set of Best Management Practices (BMP) to maintain separation of GE and conventional production. But the success of BMP depends upon the degree that growers comply. Therefore we surveyed 530 alfalfa hay and seed producer...

Intercrop movement of convergent lady beetle, Hippodamia convergens (Coleoptera: Coccinellidae), between adjacent cotton and alfalfa.

PubMed

Bastola, Anup; Parajulee, Megha N; Porter, R Patrick; Shrestha, Ram B; Chen, Fa-Jun; Carroll, Stanley C

2016-02-01

A 2-year study was conducted to characterize the intercrop movement of convergent lady beetle, Hippodamia convergens Guerin-Meneville (Coleoptera: Coccinellidae) between adjacent cotton and alfalfa. A dual protein-marking method was used to assess the intercrop movement of the lady beetles in each crop. In turns field collected lady beetles in each crop were assayed by protein specific ELISA to quantify the movement of beetles between the crops. Results indicated that a high percentage of convergent lady beetles caught in cotton (46% in 2008; 56% in 2009) and alfalfa (46% in 2008; 71% in 2009) contained a protein mark, thus indicating that convergent lady beetle movement was largely bidirectional between the adjacent crops. Although at a much lower proportion, lady beetles also showed unidirectional movement from cotton to alfalfa (5% in 2008 and 6% in 2009) and from alfalfa to cotton (9% in 2008 and 14% in 2009). The season-long bidirectional movement exhibited by the beetles was significantly higher in alfalfa than cotton during both years of the study. The total influx of lady beetles (bidirectional and unidirectional combined) was significantly higher in alfalfa compared with that in cotton for both years. While convergent lady beetles moved between adjacent cotton and alfalfa, they were more attracted to alfalfa when cotton was not flowering and/or when alfalfa offered more opportunities for prey. This study offers much needed information on intercrop movement of the convergent lady beetle that should facilitate integrated pest management decisions in cotton utilizing conservation biological control. © 2014 Institute of Zoology, Chinese Academy of Sciences.

Complete genome sequence of a new enamovirus from Argentina infecting alfalfa plants showing dwarfism symptoms.

PubMed

Bejerman, Nicolás; Giolitti, Fabián; Trucco, Verónica; de Breuil, Soledad; Dietzgen, Ralf G; Lenardon, Sergio

2016-07-01

Alfalfa dwarf disease, probably caused by synergistic interactions of mixed virus infections, is a major and emergent disease that threatens alfalfa production in Argentina. Deep sequencing of diseased alfalfa plant samples from the central region of Argentina resulted in the identification of a new virus genome resembling enamoviruses in sequence and genome structure. Phylogenetic analysis suggests that it is a new member of the genus Enamovirus, family Luteoviridae. The virus is tentatively named "alfalfa enamovirus 1" (AEV-1). The availability of the AEV-1 genome sequence will make it possible to assess the genetic variability of this virus and to construct an infectious clone to investigate its role in alfalfa dwarfism disease.

Enhancing pollination by attracting & retaining leaf cutting bees (Megachile rotundata) in alfalfa seed production fields

USDA-ARS?s Scientific Manuscript database

The alfalfa leafcutting bee, Megachile rotundata (F.), has become an important managed pollinator of alfalfa, Medicago sativa L. One problem when using alfalfa leafcutting bees as managed pollinator, is the dispersal of many females upon release, even when adequate nesting sites are present. While d...

Detection of the genetic variation of polygalacturonase-inhibiting protein gene 2 in autotetraploid alfalfa (Medicago sativa) using an improved SSCP technique.

PubMed

Gui, Z; Liu, H Q; Wang, Y; Yuan, Q H; Xin, N; Zhang, X; Li, X L; Pi, Y S; Gao, J M

2014-12-04

In this study, 2 approaches were adopted to obtain good single-strand conformation polymorphism (SSCP) data for autotetraploid alfalfa; primers were added to PCR products, and fluorescent-labeled primers were utilized. PCR-SSCP conditions for a 331-bp fragment in the coding region of polygalacturonase-inhibiting protein gene 2 in alfalfa (MsPGIP2) were optimized, and the results showed that the best SSCP gel pattern could be obtained when the loading mixture was made by mixing 1 μL PCR products, 0.2 to 0.8 μL unlabeled primers (50 μM) and 4 to 16 μL loading buffer. Furthermore, the use of the fluorescent-labeled primers resulted in 2 separated electrophoresis images from 2 complementary single DNA strands, thus making the determination of alleles and idiotypes a relatively easy task. In addition, the results of sequencing prove that the determination of alleles and idiotypes were accurate based on SSCP analysis. Finally, a total of 9 alleles with 18 SNP sites were identified for MsPGIP2 in the alfalfa variety 'Algonquin'. In conclusion, MsPGIP2 possessed great genetic variation, and the addition of primers to the PCR products in combination with the fluorescent labeling of primers could significantly improve the sensitivity and resolution of SSCP analysis. This technique could be used for genetic diversity detection and marker-assisted breeding of useful genes in autopolyploid species such as alfalfa.

Complete nucleotide sequence of Alfalfa mosaic virus isolated from alfalfa (Medicago sativa L.) in Argentina.

PubMed

Trucco, Verónica; de Breuil, Soledad; Bejerman, Nicolás; Lenardon, Sergio; Giolitti, Fabián

2014-06-01

The complete nucleotide sequence of an Alfalfa mosaic virus (AMV) isolate infecting alfalfa (Medicago sativa L.) in Argentina, AMV-Arg, was determined. The virus genome has the typical organization described for AMV, and comprises 3,643, 2,593, and 2,038 nucleotides for RNA1, 2 and 3, respectively. The whole genome sequence and each encoding region were compared with those of other four isolates that have been completely sequenced from China, Italy, Spain and USA. The nucleotide identity percentages ranged from 95.9 to 99.1 % for the three RNAs and from 93.7 to 99 % for the protein 1 (P1), protein 2 (P2), movement protein and coat protein (CP) encoding regions, whereas the amino acid identity percentages of these proteins ranged from 93.4 to 99.5 %, the lowest value corresponding to P2. CP sequences of AMV-Arg were compared with those of other 25 available isolates, and the phylogenetic analysis based on the CP gene was carried out. The highest percentage of nucleotide sequence identity of the CP gene was 98.3 % with a Chinese isolate and 98.6 % at the amino acid level with four isolates, two from Italy, one from Brazil and the remaining one from China. The phylogenetic analysis showed that AMV-Arg is closely related to subgroup I of AMV isolates. To our knowledge, this is the first report of a complete nucleotide sequence of AMV from South America and the first worldwide report of complete nucleotide sequence of AMV isolated from alfalfa as natural host.

Contribution of exopeptidases to formation of nonprotein nitrogen during ensiling of alfalfa.

PubMed

Tao, L; Zhou, H; Guo, X S; Long, R J; Zhu, Y; Cheng, W

2011-08-01

The experiment was conducted to investigate the exopeptidase classes in alfalfa (Medicago sativa L.) leaves, and to determine their contribution to the formation of nonprotein nitrogen (NPN) components during ensiling. Six classes of inhibitors that included bestatin (aminopeptidase inhibitor), potato carboxypeptidase inhibitor (PCI, carboxypeptidase inhibitor), 1,10-phenanthroline (dipeptidase inhibitor), diprotin A (dipeptidyl-peptidase inhibitor), butabindide (tripeptidyl-peptidase inhibitor), and dipeptide Phe-Arg (peptidyl-dipeptidase inhibitor) were used. To determine the contribution of each exopeptidase to the formation of NPN products, aqueous extracts of fresh alfalfa were fermented to imitate the proteolytic process of ensiled alfalfa and to ensure that each class of exopeptidase inhibitor would have immediate contact with the proteases in the alfalfa extract. Five classes of exopeptidases; namely, aminopeptidase, carboxypeptidase, dipeptidase, dipeptidyl-peptidase, and tripeptidyl-peptidase, were shown to be present in alfalfa leaves, each playing a different role in alfalfa protein degradation. Aminopeptidase, carboxypeptidase, and dipeptidase were the main exopeptidases contributing to the formation of NH(3)-N. Among the 5 exopeptidases, tripeptidyl-peptidase appeared to be the principal exopeptidase in hydrolyzing forage protein into peptides, whereas carboxypeptidase and dipeptidase appeared to be more important in contributing to the formation of amino acid-N. Dipeptidyl-peptidase and tripeptidyl-peptidase did not play a role in the formation of NH(3)-N or amino acid-N. Dipeptidase, carboxypeptidase, and tripeptidyl-peptidase were the principal exopeptidases for hydrolyzing forage protein into NPN during ensilage, and treatment with a mixture of the 5 inhibitors reduced the total NPN concentration in the fermented alfalfa extract to about 45% of that in the control after 21 d of fermentation. Copyright © 2011 American Dairy Science Association

[Alfalfa quality evaluation in the field by near-infrared reflectance spectroscopy].

PubMed

Xu, Rui-Xuan; Li, Dong-Ning; Yang, Dong-Hai; Lin, Jian-Hai; Xiang, Min; Zhang, Ying-Jun

2013-11-01

To explore the feasibility of using near-infrared reflectance spectroscopy (NIRS) to evaluate alfalfa quality rapidly in the field and try to find the appropriate machine and sample preparation method, the representative population of 170 fresh alfalfa samples collected from different regions with different stages and different cuts were scanned by a portable NIRS spectrometer (1 100 - 1 800 nm). This is the first time to build models of fresh alfalfa to rapidly estimate quality in the field for harvesting in time. The calibrations of dry matter (DM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were developed through the partial least squares regression (PLS). The determination coefficients of cross-validation (R2((CV)) were 0.831 4, 0.597 9, 0.803 6, 0.786 1 for DM, CP, NDF, ADF, respectively; the root mean standard error of cross-validation (RMSECV) were 1.241 1, 0.261 4, 0.990 3, 0.830 6; The determination coefficients of validation (R2(V)) were 0.815 0, 0.401 1, 0.784 9, 0.752 1 and the root mean standard errors of validation(RMSEP)were 1.06, 0.31, 0.95, 0.80 for DM, CP, NDF, ADF, respectively. For fresh alfalfa ,the calibration of DM, NDF, ADF can do rough quantitative analysis but the CP's calibration is failed. however, as CP in alfalfa hay is enough for animal and the DM, NDF and ADF is the crucial indicator for evaluating havest time, the model of DM, NDF and ADF can be used for evaluating the alfalfa quality rapidly in the field.

Identifying OH Imposters in the ALFALFA HI Survey

NASA Astrophysics Data System (ADS)

Suess, Katherine; Darling, Jeremiah K.; Haynes, Martha P.; Giovanelli, Riccardo

2015-01-01

OH megamasers (OHMs) are rare, luminous molecular masers that are typically observed in (ultra) luminous infrared galaxies and serve as markers of major galaxy mergers. In blind emission line surveys such as the ALFALFA (Arecibo Legacy Fast Arecibo L-Band Feed Array) survey for neutral hydrogen (HI) in the local universe, OHMs at z~0.2 can mimic z~0.05 HI lines. We present the results of optical spectroscopy of ambiguous HI detections in the ALFALFA 40% data release [1] detected by WISE but with uncertain optical counterparts. The optical redshifts, obtained from observations at the Apache Point Observatory 3.5m telescope, identified 127 HI optical counterparts and discovered five new OHMs. Fifty-six candidates remain ambiguous. The new OHMs are the first detected in a blind spectral line survey.The number of OHMs in ALFALFA matches predictions based on the OH luminosity function [2]. Additionally, the OHMs found in a blind survey do not seem to differ from those found in previous targeted surveys. This provides validation of the methods used in previous IR-selected OHM surveys and indicates there is no previously unknown OHM-producing population at z~0.2. We also provide a method for future surveys to separate OH and HI lines without expensive spectral observations. This method utilizes infrared colors and magnitudes, such as WISE mid-IR data. Since the fraction of OHMs found in flux-limited HI surveys is expected to increase with the redshift of the survey [3], this analysis can be applied to future flux-limited high-redshift hydrogen surveys.We thank the ALFALFA team for observing and producing the survey dataset. The ALFALFA team at Cornell is supported by NSF AST-1107390 and the Brinson Foundation.[1] Haynes, M. P., R. Giovanelli, A. M. Martin, K. M. Hess, A. Saintonge, et al. 2011, Astron J, 142, 142[2] Darling, J. & R. Giovanelli 2002, Astrophys J, 572, 810[3] Briggs, F. H. 1998, A&A, 336, 815

Growth dynamics of Salmonella enterica strains on alfalfa sprouts and in waste seed irrigation water.

PubMed

Howard, Michael B; Hutcheson, Steven W

2003-01-01

Alfalfa sprouts and other seed sprouts have been implicated in numerous outbreaks of salmonellosis. The source of these epidemics appears to have been low-level contamination of seeds by Salmonella bacteria that developed into clinically significant populations during the seed germination process. To test the possibility that Salmonella enterica strains carry host range determinants that allow them to grow on alfalfa, strains isolated from alfalfa or other sources were surveyed for their ability to grow on germinating alfalfa seeds. An S. enterica serovar Cubana strain originally isolated from contaminated alfalfa sprouts multiplied most rapidly during the initial 24 h of the seed germination process. Germinating alfalfa seeds supported the multiplication of S. enterica cells prior to the emergence of the root radicle at 72 h. Thereafter, much lower rates of multiplication were apparent. The ability of S. enterica to grow on germinating alfalfa seeds was independent of the serovar, isolation source, or virulence of the strain. Isolates obtained from alfalfa attained population levels similar to those observed for strains isolated from contaminated meat products or stools. Each of the strains could be detected in the waste irrigation water, with populations being strongly correlated with those detected on the germinating alfalfa seeds. The S. enterica strains were capable of utilizing the waste irrigation water as a sole carbon and nitrogen source. S. enterica strains thus appear to grow saprophytically on soluble organics released from seeds during early phases of germination. The ability to detect S. enterica in the waste irrigation water early in the germination process indicates that this method may be used as a simple way to monitor the contamination of sprouts during commercial operations.

Gas, Stars, and Star Formation in Alfalfa Dwarf Galaxies

NASA Technical Reports Server (NTRS)

Huang, Shan; Haynes, Martha P.; Giovanelli, Riccardo; Brinchmann, Jarle; Stierwalt, Sabrina; Neff, Susan G.

2012-01-01

We examine the global properties of the stellar and Hi components of 229 low H i mass dwarf galaxies extracted from the ALFALFA survey, including a complete sample of 176 galaxies with H i masses <10(sup 7.7) solar mass and Hi line widths <80 kilometers per second. Sloan Digital Sky Survey (SDSS) data are combined with photometric properties derived from Galaxy Evolution Explorer to derive stellar masses (M*) and star formation rates (SFRs) by fitting their UV-optical spectral energy distributions (SEDs). In optical images, many of the ALFALFA dwarfs are faint and of low surface brightness; only 56% of those within the SDSS footprint have a counterpart in the SDSS spectroscopic survey. A large fraction of the dwarfs have high specific star formation rates (SSFRs), and estimates of their SFRs and M* obtained by SED fitting are systematically smaller than ones derived via standard formulae assuming a constant SFR. The increased dispersion of the SSFR distribution at M* approximately less than10(exp 8)M(sub 0) is driven by a set of dwarf galaxies that have low gas fractions and SSFRs; some of these are dE/dSphs in the Virgo Cluster. The imposition of an upper Hi mass limit yields the selection of a sample with lower gas fractions for their M* than found for the overall ALFALFA population. Many of the ALFALFA dwarfs, particularly the Virgo members, have H i depletion timescales shorter than a Hubble time. An examination of the dwarf galaxies within the full ALFALFA population in the context of global star formation (SF) laws is consistent with the general assumptions that gas-rich galaxies have lower SF efficiencies than do optically selected populations and that Hi disks are more extended than stellar ones.

GAS, STARS, AND STAR FORMATION IN ALFALFA DWARF GALAXIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang Shan; Haynes, Martha P.; Giovanelli, Riccardo

2012-06-15

We examine the global properties of the stellar and H I components of 229 low H I mass dwarf galaxies extracted from the ALFALFA survey, including a complete sample of 176 galaxies with H I masses <10{sup 7.7} M{sub Sun} and H I line widths <80 km s{sup -1}. Sloan Digital Sky Survey (SDSS) data are combined with photometric properties derived from Galaxy Evolution Explorer to derive stellar masses (M{sub *}) and star formation rates (SFRs) by fitting their UV-optical spectral energy distributions (SEDs). In optical images, many of the ALFALFA dwarfs are faint and of low surface brightness; onlymore » 56% of those within the SDSS footprint have a counterpart in the SDSS spectroscopic survey. A large fraction of the dwarfs have high specific star formation rates (SSFRs), and estimates of their SFRs and M{sub *} obtained by SED fitting are systematically smaller than ones derived via standard formulae assuming a constant SFR. The increased dispersion of the SSFR distribution at M{sub *} {approx}< 10{sup 8} M{sub Sun} is driven by a set of dwarf galaxies that have low gas fractions and SSFRs; some of these are dE/dSphs in the Virgo Cluster. The imposition of an upper H I mass limit yields the selection of a sample with lower gas fractions for their M{sub *} than found for the overall ALFALFA population. Many of the ALFALFA dwarfs, particularly the Virgo members, have H I depletion timescales shorter than a Hubble time. An examination of the dwarf galaxies within the full ALFALFA population in the context of global star formation (SF) laws is consistent with the general assumptions that gas-rich galaxies have lower SF efficiencies than do optically selected populations and that H I disks are more extended than stellar ones.« less

Seed rot and damping-off of alfalfa in Minnesota caused by Pythium and Fusarium species

USDA-ARS?s Scientific Manuscript database

Globally, 15 Pythium species have been found to cause damping-off and seed rot of alfalfa, although surveys of species causing disease on alfalfa in the Midwestern U.S. are lacking. Pathogens were isolated by a seedling baiting technique from soil of five alfalfa fields in Minnesota with high levels...

Partial replacement of alfalfa fiber with fiber from ground corn cobs or wheat middlings.

PubMed

Depies, K K; Armentano, L E

1995-06-01

This trial examined the effect of using corn cobs or wheat middlings to replace alfalfa partially as the dietary fiber source for lactating cows. Multiparous midlactation cows were used in three 4 x 4 Latin squares with 21-d periods. A low fiber, basal diet contained 26.8 g of total NDF, including 14.7 g of alfalfa NDF/100 g of dietary DM. Dietary fiber was increased by addition of more alfalfa, corn cobs, or wheat middlings to obtain 27.4, 28.9, and 27.9%, respectively, of total dietary NDF. Intake (24.9 kg of DM/d) and milk yield (31.6 kg/d) were not different among treatments. Nonforage fiber sources raised milk fat concentration above basal amounts (3.1% to 3.4% fat) and decreased ruminating time below that of the high alfalfa diet (423 to 390 min/d). Fat test was raised approximately one-half as much per unit of NDF from these nonforage feeds as it was per unit of NDF from alfalfa. When additional dietary fiber came from nonforage sources, milk protein concentration (3.3%) was greater than when alfalfa provided the added fiber (3.2%).

Alfalfa Responses to Gypsum Application Measured Using Undisturbed Soil Columns

PubMed Central

Tirado-Corbalá, Rebecca; Slater, Brian K.; Dick, Warren A.; Barker, Dave

2017-01-01

Gypsum is an excellent source of Ca and S, both of which are required for crop growth. Large amounts of by-product gypsum [Flue gas desulfurization gypsum-(FGDG)] are produced from coal combustion in the United States, but only 4% is used for agricultural purposes. The objective of this study was to evaluate the effects of (1) untreated, (2) short-term (4-year annual applications of gypsum totaling 6720 kg ha−1), and (3) long-term (12-year annual applications of gypsum totaling 20,200 kg ha−1) on alfalfa (Medicago sativa L.) growth and nutrient uptake, and gypsum movement through soil. The study was conducted in a greenhouse using undisturbed soil columns of two non-sodic soils (Celina silt loam and Brookston loam). Aboveground growth of alfalfa was not affected by gypsum treatments when compared with untreated (p > 0.05). Total root biomass (0–75 cm) for both soils series was significantly increased by gypsum application (p = 0.04), however, increased root growth was restricted to 0–10 cm depth. Soil and plant analyses indicated no unfavorable environmental impact from of the 4-year and 12-year annual application of FGDG. We concluded that under sufficient water supply, by-product gypsum is a viable source of Ca and S for land application that might benefit alfalfa root growth, but has less effect on aboveground alfalfa biomass production. Undisturbed soil columns were a useful adaptation of the lysimeter method that allowed detailed measurements of alfalfa nutrient uptake, root biomass, and yield and nutrient movement in soil. PMID:28696383

Measuring the inefficiency of allowing self-pollinated alfalfa progeny into breeding nurseries

USDA-ARS?s Scientific Manuscript database

Although alfalfa is generally considered an outcrossing species the incidence of self-pollination during insect pollination can be substantial with an observed average 30% selfing rate. Despite this, alfalfa breeders utilizing space plant evaluation nurseries make no attempt to discriminate self-pol...

Selfing rate in an alfalfa seed production field pollinated with leafcutter bees

USDA-ARS?s Scientific Manuscript database

Self-pollination or “selfing” in autotetraploid alfalfa (Medicago sativa L.) (2n = 4x = 32) leads to severe inbreeding depression. Investigating selfing in alfalfa seed production may allow mitigation strategy development against potential negative impacts of selfing on varietal performance. Using m...

Influence of particle size on the effectiveness of the fiber in alfalfa silage.

PubMed

Clark, P W; Armentano, L E

2002-11-01

The objective was to determine the influence of alfalfa silage particle length on milk yield, milk composition, and chewing activity. Sixteen multiparous lactating Holsteins were used in each of two separate feeding trials over a 2-yr period providing two repetitions. Each trial was based on 4 x 4 Latin squares with 21-d periods. All four diets (2-yr average, dry basis) contained a basal level of 10.7% neutral detergent fiber from corn silage and 2.3% neutral detergent fiber from chopped alfalfagrass hay. One of the diets served as a low forage, low fiber control and contained only the basal forages. The other three diets contained an additional 8.6% neutral detergent fiber from coarser alfalfa silage, finely rechopped alfalfa silage or an equal mixture ofthe two. An increase in the forage content above the basal amount using alfalfa silage increased 4% fat-corrected milk yield, milk fat yield and concentration, eating time, and total chewing time. Dry matter intake was not influenced by diet. Linear increases in rumination and total chewing times were observed as the mean particle size of the alfalfa silage increased from finer to coarser. There was no linear effect of alfalfa silage particle size on milk yield, 4% fat-corrected milk yield, dry matter intake, or milk composition.

An Insight into microRNA156 Role in Salinity Stress Responses of Alfalfa.

PubMed

Arshad, Muhammad; Gruber, Margaret Y; Wall, Ken; Hannoufa, Abdelali

2017-01-01

Salinity is one of the major abiotic stresses affecting alfalfa productivity. Developing salinity tolerant alfalfa genotypes could contribute to sustainable crop production. The functions of microRNA156 (miR156) have been investigated in several plant species, but so far, no studies have been published that explore the role of miR156 in alfalfa response to salinity stress. In this work, we studied the role of miR156 in modulating commercially important traits of alfalfa under salinity stress. Our results revealed that overexpression of miR156 increased biomass, number of branches and time to complete growth stages, while it reduced plant height under control and salinity stress conditions. We observed a miR156-related reduction in neutral detergent fiber under non-stress, and acid detergent fiber under mild salinity stress conditions. In addition, enhanced total Kjeldahl nitrogen content was recorded in miR156 overexpressing genotypes under severe salinity stress. Furthermore, alfalfa genotypes overexpressing miR156 exhibited an altered ion homeostasis under salinity conditions. Under severe salinity stress, miR156 downregulated SPL transcription factor family genes, modified expression of other important transcription factors, and downstream salt stress responsive genes. Taken together, our results reveal that miR156 plays a role in mediating physiological and transcriptional responses of alfalfa to salinity stress.

Metabolomic Analysis of Alfalfa (Medicago sativa L.) Root-Symbiotic Rhizobia Responses under Alkali Stress.

PubMed

Song, Tingting; Xu, Huihui; Sun, Na; Jiang, Liu; Tian, Pu; Yong, Yueyuan; Yang, Weiwei; Cai, Hua; Cui, Guowen

2017-01-01

Alkaline salts (e.g., NaHCO 3 and Na 2 CO 3 ) causes more severe morphological and physiological damage to plants than neutral salts (e.g., NaCl and Na 2 SO 4 ) due to differences in pH. The mechanism by which plants respond to alkali stress is not fully understood, especially in plants having symbotic relationships such as alfalfa ( Medicago sativa L.). Therefore, a study was designed to evaluate the metabolic response of the root-nodule symbiosis in alfalfa under alkali stress using comparative metabolomics. Rhizobium-nodulized (RI group) and non-nodulized (NI group) alfalfa roots were treated with 200 mmol/L NaHCO 3 and, roots samples were analyzed for malondialdehydyde (MDA), proline, glutathione (GSH), superoxide dismutase (SOD), and peroxidase (POD) content. Additionally, metabolite profiling was conducted using gas chromatography combined with time-of-flight mass spectrometry (GC/TOF-MS). Phenotypically, the RI alfalfa exhibited a greater resistance to alkali stress than the NI plants examined. Physiological analysis and metabolic profiling revealed that RI plants accumulated more antioxidants (SOD, POD, GSH), osmolytes (sugar, glycols, proline), organic acids (succinic acid, fumaric acid, and alpha-ketoglutaric acid), and metabolites that are involved in nitrogen fixation. Our pairwise metabolomics comparisons revealed that RI alfalfa plants exhibited a distinct metabolic profile associated with alkali putative tolerance relative to NI alfalfa plants. Data provide new information about the relationship between non-nodulized, rhizobium-nodulized alfalfa and alkali resistance.

Metabolomic Analysis of Alfalfa (Medicago sativa L.) Root-Symbiotic Rhizobia Responses under Alkali Stress

PubMed Central

Song, Tingting; Xu, Huihui; Sun, Na; Jiang, Liu; Tian, Pu; Yong, Yueyuan; Yang, Weiwei; Cai, Hua; Cui, Guowen

2017-01-01

Alkaline salts (e.g., NaHCO3 and Na2CO3) causes more severe morphological and physiological damage to plants than neutral salts (e.g., NaCl and Na2SO4) due to differences in pH. The mechanism by which plants respond to alkali stress is not fully understood, especially in plants having symbotic relationships such as alfalfa (Medicago sativa L.). Therefore, a study was designed to evaluate the metabolic response of the root-nodule symbiosis in alfalfa under alkali stress using comparative metabolomics. Rhizobium-nodulized (RI group) and non-nodulized (NI group) alfalfa roots were treated with 200 mmol/L NaHCO3 and, roots samples were analyzed for malondialdehydyde (MDA), proline, glutathione (GSH), superoxide dismutase (SOD), and peroxidase (POD) content. Additionally, metabolite profiling was conducted using gas chromatography combined with time-of-flight mass spectrometry (GC/TOF-MS). Phenotypically, the RI alfalfa exhibited a greater resistance to alkali stress than the NI plants examined. Physiological analysis and metabolic profiling revealed that RI plants accumulated more antioxidants (SOD, POD, GSH), osmolytes (sugar, glycols, proline), organic acids (succinic acid, fumaric acid, and alpha-ketoglutaric acid), and metabolites that are involved in nitrogen fixation. Our pairwise metabolomics comparisons revealed that RI alfalfa plants exhibited a distinct metabolic profile associated with alkali putative tolerance relative to NI alfalfa plants. Data provide new information about the relationship between non-nodulized, rhizobium-nodulized alfalfa and alkali resistance. PMID:28744296

Bacterial stem blight of alfalfa: A disease that increases frost damage

USDA-ARS?s Scientific Manuscript database

Alfalfa producers count on the first harvest in late spring to deliver the highest tonnage and best quality of forage of the year. A late frost can significantly reduce both yield and quality. Losses are due not only to the physical damage from freezing of the alfalfa stem and leaves but also from d...

The importance of potassium in resistance to crown rot disease in alfalfa

USDA-ARS?s Scientific Manuscript database

Nitrogen, phosphate, and potassium (potash, K2O) are the three most important nutrients in alfalfa growth and development. Nitrogen fertilization is not required because alfalfa has a high rate of biological nitrogen fixation. Phosphorus and potassium are frequently applied as fertilizer, but potass...

A first report and complete genome sequence of alfalfa enamovirus from Sudan

USDA-ARS?s Scientific Manuscript database

A full genome sequence of a viral pathogen, provisionally named alfalfa enamovirus 2 (AEV-2), was reconstructed from short reads obtained by Illumina RNA sequencing of alfalfa sample originating from Sudan. Ambiguous nucleotides in the resultant consensus assembly and identity of the predicted virus...

Forage accumulation and nutritive value of reduced lignin and reference alfalfa cultivars

USDA-ARS?s Scientific Manuscript database

Reduced lignin alfalfa (Medicago sativa L.) cultivars have the potential to increase the feeding value of alfalfa for livestock by improving the forage fiber digestibility and to increase harvest management flexibility. The objectives were to compare the yield and forage nutritive value of reduced ...

Do glyphosate resistant feral plants and hay fields spread the transgene to conventional alfalfa seed fields?

USDA-ARS?s Scientific Manuscript database

In addition to meeting domestic needs, large amounts of alfalfa seed and hay produced in the US are being exported overseas. Because alfalfa is an insect pollinated crop, gene flow is a concern. Adding to this alfalfa readily naturalizes along roadsides, irrigation ditches, and unmanaged habitats; a...

Environmental impact assessment of alfalfa (Medicago sativa L.) hay production.

PubMed

Bacenetti, Jacopo; Lovarelli, Daniela; Tedesco, Doriana; Pretolani, Roberto; Ferrante, Valentina

2018-09-01

On-farm production of hay and high-protein-content feed has several advantages such as diversification of on-farm cultivated crops, reduction of off-farm feed concentrates transported over long distances and a reduction in runoff during the winter season if grown crops are perennial. Among those crops cultivated for high-protein-content feed, alfalfa (Medicago sativa L.) is one of the most important in the Italian context. Nevertheless, up to now, only a few studies have assessed the environmental performance of alfalfa hay production. In this study, using the Life Cycle Assessment approach, the environmental impact of alfalfa hay production in Northern Italy was analyzed. More in detail, two production practices (without and with irrigation) were compared. The results show that alfalfa hay production in irrigated fields has a better environmental performance compared to non-irrigated production, mainly because of the yield increase achieved with irrigation. In particular, for the Climate Change impact category, the impact is equal to 84.54 and 80.21kgCO 2 /t of hay for the scenario without and with irrigation, respectively. However, for two impact categories (Ozone Depletion and Human Toxicity-No Cancer Effect), the impact of irrigation completely offsets the yield increase, and the cultivation practice without irrigation shows the best environmental performance. For both scenarios, the mechanization of harvest is the main environmental hotspot, mostly due to fuel consumption and related combustion emissions. Wide differences were highlighted by comparing the two scenarios with the Ecoinvent process of alfalfa hay production; these differences are mostly due to the cultivation practice and, in particular, to the more intensive fertilization in Swiss production. Copyright © 2018 Elsevier B.V. All rights reserved.

Animal feed compositions containing phytase derived from transgenic alfalfa and methods of use thereof

DOEpatents

Austin-Phillips, Sandra; Koegel, Richard G.; Straub, Richard J.; Cook, Mark

1999-01-01

A value-added composition of matter containing plant matter from transgenic alfalfa which expresses exogenous phytase activity is disclosed. The phytase activity is a gene product of an exogenous gene encoding for phytase which has been stably incorporated into the genome of alfalfa plants. The transgenic alfalfa expresses phytase activity in nutritionally-significant amounts, thereby enabling its use in animal feeds to eliminate the need for phosphorous supplementation of livestock, poultry, and fish feed rations.

Animal feed compositions containing phytase derived from transgenic alfalfa and methods of use thereof

DOEpatents

Austin-Phillips, Sandra; Koegel, Richard G.; Straub, Richard J.; Cook, Mark

2001-01-01

A value-added composition of matter containing plant matter from transgenic alfalfa which expresses exogenous phytase activity is disclosed. The phytase activity is a gene product of an exogenous gene encoding for phytase which has been stably incorporated into the genome of alfalfa plants. The transgenic alfalfa expresses phytase activity in nutritionally-significant amounts, thereby enabling its use in animal feeds to eliminate the need for phosphorous supplementation of livestock, poultry, and fish feed rations.

Maximizing the expression of transgenic traits into elite alfalfa germplasm using a supertransgene configuration in heterozygous conditions.

PubMed

Jozefkowicz, Cintia; Frare, Romina; Fox, Romina; Odorizzi, Ariel; Arolfo, Valeria; Pagano, Elba; Basigalup, Daniel; Ayub, Nicolas; Soto, Gabriela

2018-05-01

A novel process for the production of transgenic alfalfa varieties. Numerous species of legumes, including alfalfa, are critical factors for agroecosystems due to their ability to grow without nitrogen fertilizers derived from non-renewable fossil fuels, their contribution of organic nitrogen to the soil, and their increased nutritional value. Alfalfa is the main source of vegetable proteins in meat and milk production systems worldwide. Despite the economic and ecological importance of this autotetraploid and allogamous forage crop, little progress has been made in the incorporation of transgenic traits into commercial alfalfa. This is mainly due to the unusually strong transgene silencing and complex reproductive behavior of alfalfa, which limit the production of events with high transgene expression and the introgression of selected events within heterogeneous synthetic populations, respectively. In this report, we describe a novel procedure, called supertransgene process, where a glufosinate-tolerant alfalfa variety was developed using a single event containing the BAR transgene associated with an inversion. This approach can be used to maximize the expression of transgenic traits into elite alfalfa germplasm and to reduce the cost of production of transgenic alfalfa cultivars, contributing to the public improvement of this legume forage and other polyploid and outcrossing crop species.

Inactivation of Human Norovirus and Its Surrogates on Alfalfa Seeds by Aqueous Ozone.

PubMed

Wang, Qing; Markland, Sarah; Kniel, Kalmia E

2015-08-01

Alfalfa sprouts have been associated with numerous foodborne outbreaks. Previous studies investigated the effectiveness of aqueous ozone on bacterially contaminated seeds, yet little is known about the response of human norovirus (huNoV). This study assessed aqueous ozone for the disinfection of alfalfa seeds contaminated with huNoV and its surrogates. The inactivation of viruses without a food matrix was also investigated. Alfalfa seeds were inoculated with huNoV genogroup II, Tulane virus (TV), and murine norovirus (MNV); viruses alone or inoculated on seeds were treated in deionized water containing 6.25 ppm of aqueous ozone with agitation at 22°C for 0.5, 1, 5, 15, or 30 min. The data showed that aqueous ozone resulted in reductions of MNV and TV infectivity from 1.66 ± 1.11 to 5.60 ± 1.11 log PFU/g seeds; for all treatment times, significantly higher reductions were observed for MNV (P < 0.05). Viral genomes were relatively resistant, with a reduction of 1.50 ± 0.14 to 3.00 ± 0.14 log genomic copies/g seeds; the reduction of TV inoculated in water was similar to that of huNoV, whereas MNV had significantly greater reductions in genomic copies (P < 0.05). Similar trends were observed in ozone-treated viruses alone, with significantly higher levels of inactivation (P < 0.05), especially with reduced levels of infectivity for MNV and TV. The significant inactivation by aqueous ozone indicates that ozone may be a plausible substitute for chlorine as an alternative treatment for seeds. The behavior of TV was similar to that of huNoV, which makes it a promising surrogate for these types of scenarios.

Identification of Alfalfa Leaf Diseases Using Image Recognition Technology

PubMed Central

Qin, Feng; Liu, Dongxia; Sun, Bingda; Ruan, Liu; Ma, Zhanhong; Wang, Haiguang

2016-01-01

Common leaf spot (caused by Pseudopeziza medicaginis), rust (caused by Uromyces striatus), Leptosphaerulina leaf spot (caused by Leptosphaerulina briosiana) and Cercospora leaf spot (caused by Cercospora medicaginis) are the four common types of alfalfa leaf diseases. Timely and accurate diagnoses of these diseases are critical for disease management, alfalfa quality control and the healthy development of the alfalfa industry. In this study, the identification and diagnosis of the four types of alfalfa leaf diseases were investigated using pattern recognition algorithms based on image-processing technology. A sub-image with one or multiple typical lesions was obtained by artificial cutting from each acquired digital disease image. Then the sub-images were segmented using twelve lesion segmentation methods integrated with clustering algorithms (including K_means clustering, fuzzy C-means clustering and K_median clustering) and supervised classification algorithms (including logistic regression analysis, Naive Bayes algorithm, classification and regression tree, and linear discriminant analysis). After a comprehensive comparison, the segmentation method integrating the K_median clustering algorithm and linear discriminant analysis was chosen to obtain lesion images. After the lesion segmentation using this method, a total of 129 texture, color and shape features were extracted from the lesion images. Based on the features selected using three methods (ReliefF, 1R and correlation-based feature selection), disease recognition models were built using three supervised learning methods, including the random forest, support vector machine (SVM) and K-nearest neighbor methods. A comparison of the recognition results of the models was conducted. The results showed that when the ReliefF method was used for feature selection, the SVM model built with the most important 45 features (selected from a total of 129 features) was the optimal model. For this SVM model, the

Identification of Alfalfa Leaf Diseases Using Image Recognition Technology.

PubMed

Qin, Feng; Liu, Dongxia; Sun, Bingda; Ruan, Liu; Ma, Zhanhong; Wang, Haiguang

2016-01-01

Common leaf spot (caused by Pseudopeziza medicaginis), rust (caused by Uromyces striatus), Leptosphaerulina leaf spot (caused by Leptosphaerulina briosiana) and Cercospora leaf spot (caused by Cercospora medicaginis) are the four common types of alfalfa leaf diseases. Timely and accurate diagnoses of these diseases are critical for disease management, alfalfa quality control and the healthy development of the alfalfa industry. In this study, the identification and diagnosis of the four types of alfalfa leaf diseases were investigated using pattern recognition algorithms based on image-processing technology. A sub-image with one or multiple typical lesions was obtained by artificial cutting from each acquired digital disease image. Then the sub-images were segmented using twelve lesion segmentation methods integrated with clustering algorithms (including K_means clustering, fuzzy C-means clustering and K_median clustering) and supervised classification algorithms (including logistic regression analysis, Naive Bayes algorithm, classification and regression tree, and linear discriminant analysis). After a comprehensive comparison, the segmentation method integrating the K_median clustering algorithm and linear discriminant analysis was chosen to obtain lesion images. After the lesion segmentation using this method, a total of 129 texture, color and shape features were extracted from the lesion images. Based on the features selected using three methods (ReliefF, 1R and correlation-based feature selection), disease recognition models were built using three supervised learning methods, including the random forest, support vector machine (SVM) and K-nearest neighbor methods. A comparison of the recognition results of the models was conducted. The results showed that when the ReliefF method was used for feature selection, the SVM model built with the most important 45 features (selected from a total of 129 features) was the optimal model. For this SVM model, the

The Role of Proanthocyanidins Complex in Structure and Nutrition Interaction in Alfalfa Forage

PubMed Central

Jonker, Arjan; Yu, Peiqiang

2016-01-01

Alfalfa (Medicago sativa L.) is one of the main forages grown in the world. Alfalfa is a winter hardy, drought tolerant, N-fixing legume with a good longevity, high yield, high nutrient levels, high digestibility, unique structural to non-structural components ratio, high dry matter intake, and high animal productivity per hectare. However, its main limitation is its excessively rapid initial rate of protein degradation in the rumen, which results in pasture bloat and inefficient use of protein with consequent excessive excretions of nitrogen into the environment. Proanthocyanidins are secondary plant metabolites that can bind with protein and thereby reduce the rate and extent of ruminal protein degradation. However, these secondary metabolites do not accumulate in alfalfa. This review aims to firstly describe the events involved in the rapid release of protein from alfalfa and its effect on ruminant nutrition, environmental pollution, and pasture bloat; secondly, to describe occurrence, structure, functions and benefits of moderate amounts of proanthocyanidin; and finally, to describe the development of alfalfa which accumulates moderate amounts of proanthocyanidins. The emphasis of this review focuses on the role of proanthocyanidins compounds in structure and nutrition interaction in ruminant livestock systems. PMID:27223279

The Role of Proanthocyanidins Complex in Structure and Nutrition Interaction in Alfalfa Forage.

PubMed

Jonker, Arjan; Yu, Peiqiang

2016-05-23

Alfalfa (Medicago sativa L.) is one of the main forages grown in the world. Alfalfa is a winter hardy, drought tolerant, N-fixing legume with a good longevity, high yield, high nutrient levels, high digestibility, unique structural to non-structural components ratio, high dry matter intake, and high animal productivity per hectare. However, its main limitation is its excessively rapid initial rate of protein degradation in the rumen, which results in pasture bloat and inefficient use of protein with consequent excessive excretions of nitrogen into the environment. Proanthocyanidins are secondary plant metabolites that can bind with protein and thereby reduce the rate and extent of ruminal protein degradation. However, these secondary metabolites do not accumulate in alfalfa. This review aims to firstly describe the events involved in the rapid release of protein from alfalfa and its effect on ruminant nutrition, environmental pollution, and pasture bloat; secondly, to describe occurrence, structure, functions and benefits of moderate amounts of proanthocyanidin; and finally, to describe the development of alfalfa which accumulates moderate amounts of proanthocyanidins. The emphasis of this review focuses on the role of proanthocyanidins compounds in structure and nutrition interaction in ruminant livestock systems.

ALFALFA DISCOVERY OF THE MOST METAL-POOR GAS-RICH GALAXY KNOWN: AGC 198691

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hirschauer, Alec S.; Salzer, John J.; Rhode, Katherine L., E-mail: ash@astro.indiana.edu, E-mail: slaz@astro.indiana.edu, E-mail: krhode@indiana.edu

We present spectroscopic observations of the nearby dwarf galaxy AGC 198691. This object is part of the Survey of H i in Extremely Low-Mass Dwarfs project, which is a multi-wavelength study of galaxies with H i masses in the range of 10{sup 6}–10{sup 7.2} M {sub ⊙}, discovered by the Arecibo Legacy Fast ALFA (ALFALFA) survey. We have obtained spectra of the lone H ii region in AGC 198691 with the new high-throughput KPNO Ohio State Multi-Object Spectrograph on the Mayall 4 m, as well as with the Blue Channel spectrograph on the MMT 6.5 m telescope. These observations enablemore » the measurement of the temperature-sensitive [O iii] λ 4363 line and hence the determination of a “direct” oxygen abundance for AGC 198691. We find this system to be an extremely metal-deficient (XMD) system with an oxygen abundance of 12+log(O/H) = 7.02 ± 0.03, making AGC 198691 the lowest-abundance star-forming galaxy known in the local universe. Two of the five lowest-abundance galaxies known have been discovered by the ALFALFA blind H i survey; this high yield of XMD galaxies represents a paradigm shift in the search for extremely metal-poor galaxies.« less

Alfalfa (Medicago sativa L.) seed yield in relation to phosphorus fertilization and honeybee pollination.

PubMed

Al-Kahtani, Saad Naser; Taha, El-Kazafy Abdou; Al-Abdulsalam, Mohammed

2017-07-01

This investigation was conducted at the Agricultural and Veterinary Training and Research Station, King Faisal University, Al-Ahsa, Saudi Arabia, during the alfalfa growing season in 2014. The study aimed to evaluate the impact of phosphorus fertilization and honeybee pollination on alfalfa seed production. The experiment was divided into 9 treatments of open pollination, honeybee pollination, and non-pollination with three different levels (0, 300 or 600 kg P 2 O 5 /ha/year) of triple super phosphate. All vegetative growth attributes of Hassawi alfalfa were significantly higher in the non-insect pollination plots, while the yield and yield component traits were significantly higher with either open pollination or honeybee pollination in parallel with the increasing level of phosphorus fertilizer up to 600 kg P 2 O 5 /ha/year in light salt-affected loamy sand soils. There was no seed yield in Hassawi alfalfa without insect pollination. Therefore, placing honeybee colonies near the fields of Hassawi alfalfa and adding 600 kg P 2 O 5 /ha/year can increase seed production.

Study on the reduction and hysteresis effect of soil nitrogen pollution by Alfalfa in channel buffer bank

NASA Astrophysics Data System (ADS)

Chi, Yixia; Xue, Lianqing; Zhang, Zhanyu; Li, Dongying

2018-01-01

Based on the simulation experiments of solute transport in channel buffer bank and pot experiments, this study analyzed the transport of nitrogen pollution from farmland drains along the South-North Water Transfer east route project; and compared the nitrogen transport rule and purification effect of alfalfa in channel buffer bank soil under situations of bare land and alfalfa mulching. The results showed that: (1) soil nitrogen content decreased gradually with the width increase of channel buffer bank by the soil adsorption and decomposition; (2) the migration rates of nitrogen were 0.06 g·kg-1 by the alfalfa mulching; (3) the removed rates of nitrogen from the soil were 0.088 g·kg-1 by cutting alfalfa; (4) the residual nitrogen of soil with alfalfa was 10% of the bare land. Alfalfa in channel buffer bank had obvious reduction and hysteresis effect to soil nitrogen pollution.

[Determination of Hard Rate of Alfalfa (Medicago sativa L.) Seeds with Near Infrared Spectroscopy].

PubMed

Wang, Xin-xun; Chen, Ling-ling; Zhang, Yun-wei; Mao, Pei-sheng

2016-03-01

Alfalfa (Medicago sativa L.) is the most commonly grown forage crop due to its better quality characteristics and high adaptability in China. However, there was 20%-80% hard seeds in alfalfa which could not be identified easily from non hard seeds which would cause the loss of seed utilization value and plant production. This experiment was designed for 121 samples of alfalfa. Seeds were collected according to different regions, harvested year and varieties. 31 samples were artificial matched as hard rates ranging from 20% to 80% to establish a model for hard seed rate by near infrared spectroscopy (NIRS) with Partial Least Square (PLS). The objective of this study was to establish a model and to estimate the efficiency of NIRS for determining hard rate of alfalfa seeds. The results showed that the correlation coefficient (R2(cal)) of calibration model was 0.981 6, root mean square error of cross validation (RMSECV) was 5.32, and the ratio of prediction to deviation (RPD) was 3.58. The forecast model in this experiment presented the satisfied precision. The proposed method using NIRS technology is feasible for identification and classification of hard seed in alfalfa. A new method, as nondestructive testing of hard seed rate, was provided to theoretical basis for fast nondestructive detection of hard seed rates in alfalfa.

Water savings from reduced alfalfa cropping in California's Upper San Joaquin Valley

NASA Astrophysics Data System (ADS)

Singh, K. K.; Gray, J.

2017-12-01

Water and food and forage security are inextricably linked. In fact, 90% of global freshwater is consumed for food production. Food demand increases as populations grow and diets change, making water increasingly scarce. This tension is particularly acute, contentious, and popularly appreciated in California's Central Valley, which is one of the most important non-grain cropping areas in the United States. While the water-intensive production of tree nuts like almonds and pistachios has received the most popular attention, it is California's nation-leading alfalfa production that consumes the most water. Alfalfa, the "Queen of Forages" is the preferred feedstock for California's prodigious dairy industry. It is grown year-round, and single fields can be harvested more than four times a year; a practice which can require in excess of 1.5 m of irrigation water. Given the water scarcity in the region, the production of alfalfa is under increasing scrutiny with respect to long-term sustainability. However, the potential water savings associated with alternative crops, and various levels of alfalfa replacement have not been quantified. Here, we address that knowledge gap by simulating the ecohydrology of the Upper San Joaquin's cropping system under various scenarios of alfalfa crop replacement with crops of comparable economic value. Specifically, we use the SWAT model to evaluate the water savings that would be realized at 33%, 66%, and 100% alfalfa replacement with economically comparable, but more water efficient crops such as tomatoes. Our results provide an important quantification of the potential water savings under alternative cropping systems that, importantly, also addresses the economic concerns of farmers. Results like these provide critical guidance to farmers and land/water decision makers as they plan for a more sustainable and productive agricultural future.

Physiological response of glandular-haired alfalfa to potato leafhopper (Hemiptera: Cicadellidae) injury.

PubMed

Lamp, W O; Alexander, L C; Nguyen, M

2007-02-01

Plant tolerance to herbivory is a key approach for managing pests. In alfalfa, Medicago sativa, the potato leafhopper, Empoasca fabae, is a major pest as a result of the cascade of plant responses to piercing-sucking injury. To identify tolerance to its injury based on alfalfa physiology, experiments were conducted in the field and greenhouse. In our comparison of the response of field-grown alfalfa cultivars to standardized leafhopper densities, net photosynthesis and transpiration rates of 'Geneva' leaves were reduced by 18 and 21%, respectively, by leafhopper presence compared with a rate change of <1% of resistant 'EverGreen' leaves. Under greenhouse conditions, alfalfa clones varied in their level of gas exchange (net photosynthesis and transpiration) and stem elongation responses to leafhopper injury. For example, in the comparison of seven clones, net photosynthesis declined an average of 40.7% with leafhopper injury, although individual clones varied from 26.6 to 74.3% reduction. Internode elongation after 2 d was 60.3% less on injured stems compared with healthy stems, but again, the individual clones varied from 17.3 to 91.9%. In a time-course study of selected clones, clones varied in their level of injury just after and 3 d after insect removal. Gas exchange responses of all clones recovered by 7 d after cessation of injury. In a choice test, leafhoppers spent similar amounts of time on the susceptible clone and the most tolerant clone; however, their precise feeding behaviors were not measured. Thus, the variable response of clones to injury may be either true physiological tolerance or antixenosis from a change in feeding behavior. This study showed putative tolerance to leafhopper injury among alfalfa genotypes, suggesting that tolerance could be the basis for crop protection in alfalfa from potato leafhopper injury.

Thermal inactivation of Salmonella and Escherichia coli O157:H7 on alfalfa seeds.

PubMed

Feng, Guoping; Churey, John J; Worobo, Randy W

2007-07-01

Alfalfa seeds inoculated with five strains of Salmonella or Escherichia coli O157:H7 were subjected to dry heat at 55 degrees C for up to 8 days. Five-log reductions in Salmonella or E. coli O157:H7 on seeds were observed. No pathogens were detected on the sprouted seeds, which were initially inoculated with ca. 2 log CFU/g of Salmonella or more than 8 log CFU/g of E. coli O157:H7. The percentages of germination of the alfalfa seeds did not significantly decrease after 6 days of heating at 55 degrees C. These results showed that heat treatment of alfalfa seeds at 55 degrees C for up to 6 days was effective in enhancing the safety of alfalfa sprouts without affecting germination significantly.

VizieR Online Data Catalog: HI-bearing ultra-diffuse ALFALFA galaxies (Leisman+, 2017)

NASA Astrophysics Data System (ADS)

Leisman, L.; Haynes, M. P.; Janowiecki, S.; Hallenbeck, G.; Jozsa, G.; Giovanelli, R.; Adams, E. A. K.; Neira, D. B.; Cannon, J. M.; Janesh, W. F.; Rhode, K. L.; Salzer, J. J.

2018-02-01

All sources discussed here have available SDSS and ALFALFA data. The ALFALFA observations, data reduction, and catalog products are detailed elsewhere (e.g., Giovanelli+ 2005AJ....130.2598G ; Saintonge 2007AJ....133.2087S ; Haynes+ 2011, J/AJ/142/170). (1 data file).

Improving ethanol production from alfalfa stems via ambient-temperature acid pretreatment and washing

USDA-ARS?s Scientific Manuscript database

The concept of co-production of liquid fuel (ethanol) along with animal feed on farm was proposed. The strategy of using ambient-temperature acid pretreatment, ensiling, and washing to improve ethanol production from alfalfa stems was investigated. Alfalfa stems were separated and pretreated with su...

Transgenic Alfalfa Plants Expressing the Sweetpotato Orange Gene Exhibit Enhanced Abiotic Stress Tolerance

PubMed Central

Wang, Zhi; Ke, Qingbo; Kim, Myoung Duck; Kim, Sun Ha; Ji, Chang Yoon; Jeong, Jae Cheol; Lee, Haeng-Soon; Park, Woo Sung; Ahn, Mi-Jeong; Li, Hongbing; Xu, Bingcheng; Deng, Xiping; Lee, Sang-Hoon; Lim, Yong Pyo; Kwak, Sang-Soo

2015-01-01

Alfalfa (Medicago sativa L.), a perennial forage crop with high nutritional content, is widely distributed in various environments worldwide. We recently demonstrated that the sweetpotato Orange gene (IbOr) is involved in increasing carotenoid accumulation and enhancing resistance to multiple abiotic stresses. In this study, in an effort to improve the nutritional quality and environmental stress tolerance of alfalfa, we transferred the IbOr gene into alfalfa (cv. Xinjiang Daye) under the control of an oxidative stress-inducible peroxidase (SWPA2) promoter through Agrobacterium tumefaciens-mediated transformation. Among the 11 transgenic alfalfa lines (referred to as SOR plants), three lines (SOR2, SOR3, and SOR8) selected based on their IbOr transcript levels were examined for their tolerance to methyl viologen (MV)-induced oxidative stress in a leaf disc assay. The SOR plants exhibited less damage in response to MV-mediated oxidative stress and salt stress than non-transgenic plants. The SOR plants also exhibited enhanced tolerance to drought stress, along with higher total carotenoid levels. The results suggest that SOR alfalfa plants would be useful as forage crops with improved nutritional value and increased tolerance to multiple abiotic stresses, which would enhance the development of sustainable agriculture on marginal lands. PMID:25946429

Extraction, composition, and functional properties of dried alfalfa (Medicago sativa L.) leaf protein.

PubMed

Hojilla-Evangelista, Mila P; Selling, Gordon W; Hatfield, Ronald; Digman, Matthew

2017-02-01

Alfalfa is considered a potential feedstock for biofuels; co-products with value-added uses would enhance process viability. This work evaluated dried alfalfa leaves for protein production and describes the functional properties of the protein. Dried alfalfa leaves contained 260 g kg -1 dry basis (DB) crude protein, with albumins being the major fraction (260 g kg -1 of total protein). Alkali solubilization for 2 h at 50 °C, acid precipitation, dialysis, and freeze-drying produced a protein concentrate (600 g kg -1 DB crude protein). Alfalfa leaf protein concentrate showed moderate solubility (maximum 500 g kg -1 soluble protein from pH 5.5 to 10), excellent emulsifying properties (activity 158-219 m 2  g -1 protein, stability 17-49 min) and minimal loss of solubility during heating at pH ≥ 7.0. It is technically feasible to extract protein with desirable emulsifying and heat stability properties from dried alfalfa leaves; however, the dried form may not be a practical starting material for protein production, given the difficulty of achieving high yields and high-purity protein product. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Transgenic alfalfa plants expressing the sweetpotato Orange gene exhibit enhanced abiotic stress tolerance.

PubMed

Wang, Zhi; Ke, Qingbo; Kim, Myoung Duck; Kim, Sun Ha; Ji, Chang Yoon; Jeong, Jae Cheol; Lee, Haeng-Soon; Park, Woo Sung; Ahn, Mi-Jeong; Li, Hongbing; Xu, Bingcheng; Deng, Xiping; Lee, Sang-Hoon; Lim, Yong Pyo; Kwak, Sang-Soo

2015-01-01

Alfalfa (Medicago sativa L.), a perennial forage crop with high nutritional content, is widely distributed in various environments worldwide. We recently demonstrated that the sweetpotato Orange gene (IbOr) is involved in increasing carotenoid accumulation and enhancing resistance to multiple abiotic stresses. In this study, in an effort to improve the nutritional quality and environmental stress tolerance of alfalfa, we transferred the IbOr gene into alfalfa (cv. Xinjiang Daye) under the control of an oxidative stress-inducible peroxidase (SWPA2) promoter through Agrobacterium tumefaciens-mediated transformation. Among the 11 transgenic alfalfa lines (referred to as SOR plants), three lines (SOR2, SOR3, and SOR8) selected based on their IbOr transcript levels were examined for their tolerance to methyl viologen (MV)-induced oxidative stress in a leaf disc assay. The SOR plants exhibited less damage in response to MV-mediated oxidative stress and salt stress than non-transgenic plants. The SOR plants also exhibited enhanced tolerance to drought stress, along with higher total carotenoid levels. The results suggest that SOR alfalfa plants would be useful as forage crops with improved nutritional value and increased tolerance to multiple abiotic stresses, which would enhance the development of sustainable agriculture on marginal lands.

Alfalfa dodder (Cuscuta campestris) toxicity in horses: clinical, haematological and serum biochemical findings.

PubMed

Abutarbush, S M

2013-07-27

The objective of this observational study is to describe clinical, haematological and serum biochemical findings of horses affected with alfalfa dodder (Cuscuta campestris) toxicity. Twenty horses naturally exposed to alfalfa dodder toxicity were examined and information was collected on history and clinical signs. Physical examination was done on horses in the premises (n=20), and venous blood samples of 12 horses were submitted for haematology and serum biochemical examination for each horse. Abnormal clinical signs started around 36 hours after horses were fed the contaminated alfalfa. Abnormal signs were seen in 11 horses and those included diarrhoea (n=8), decreased appetite (n=7), neurological signs (n=4) and abdominal pain (n=1). Some horses had multiple clinical signs of the above. The results of complete blood cell count revealed leukocytopenia, neutropenia and thrombocytopenia. Serum biochemical analysis revealed decreased ALP, AST and CPK levels and increased direct bilirubin level. The used alfalfa was stopped immediately and a different alfalfa from a new container that did not contain any weeds was fed. Horses on the premises were observed closely, and the abnormal clinical signs resolved within three days. No treatment was implemented. Knowledge about toxicity of horses by Cuscuta species is scarce in the English veterinary literature and very limited.

The Undergraduate ALFALFA Groups Project: Properties of the Galaxy Group MKW 11

NASA Astrophysics Data System (ADS)

Manglitz, Scott; Russell, P.; Turner, J.; Crone, M.

2009-01-01

The Undergraduate ALFALFA team is an NSF-funded collaboration of 14 institutions that supports undergraduate research using data from the Arecibo Legacy Fast ALFA (ALFALFA) survey. As part of this project, we are examining MKW 11, a galaxy group with an unusual, irregular X-ray distribution centered on what appears to be an X-ray bright tidal filament. Its optical velocity distribution is large and non-Gaussian, suggesting that it is in the process of merging. Here we present the position and velocity structure of MKW 11 using the radio sources in the blind ALFALFA survey. Besides a complicated structure, our results suggest a deficiency of HI gas in galaxies that are near the center of the group.

The demography of feral alfalfa (Medicago sativa L.) populations occurring in roadside habitats in Southern Manitoba, Canada: implications for novel trait confinement.

PubMed

Bagavathiannan, Muthukumar V; Gulden, Robert H; Begg, Graham S; Van Acker, Rene C

2010-09-01

Feral populations of cultivated crops can act as reservoirs for novel genetically engineered (GE) traits and aid in trait movement at the landscape level. However, little information is available on the potential of cultivated crops to become feral. In this study, we investigated the ferality of alfalfa populations (non-GE version) occurring in roadside habitats. Knowledge on the nature of roadside alfalfa populations would be useful for designing efficient trait confinement protocols and coexistence strategies in alfalfa. We investigated roadside alfalfa populations from 2006 to 2009 in three rural municipalities (Hanover, MacDonald, and Springfield) in Southern Manitoba, Canada. We studied the demography of these populations including seedbank, seedling recruitment, and fecundity and examined the impact of road verge mowing on key life stages of these populations. We also compared the growth and reproductive attributes of roadside and cultivated alfalfa populations. Alfalfa is reproductively successful in roadside habitats and capable of establishing self-perpetuating populations. A substantial portion of the alfalfa seeds we extracted from seedbank samples were viable but not germinable, suggesting some degree of seedbank persistence in roadside habitats. In the roadside habitat, alfalfa seedlings recruited successfully, however, seedling mortality was high when seedlings were in close proximity to well-established alfalfa plants. Mowing dramatically reduced the reproductive success of roadside alfalfa. Generally, the growth and reproduction of roadside alfalfa was comparable to cultivated alfalfa except for total fecundity. Considering the long lifespan (>10 years) of alfalfa and the levels of fecundity, seedbank, and seedling survival we observed, long-term persistence of roadside alfalfa populations seems reasonable. In the context of novel trait confinement, our results suggest that feral alfalfa populations required to be managed if there is a desire

Extraction, composition, and functional properties of dried alfalfa (Medicago sativa L.) leaf protein

USDA-ARS?s Scientific Manuscript database

Alfalfa, traditionally used for animal feed, has attracted attention as a potential feedstock for biofuels and the viability of the process would be enhanced by co-products with value-added uses. This study describes extraction of protein from dried alfalfa leaves and the functional properties of th...

Prohexadione-calcium improves stand density and yield of alfalfa interseeded into silage corn

USDA-ARS?s Scientific Manuscript database

Interseeded alfalfa (Medicago sativa L.) could serve as a dual-purpose crop to provide groundcover for silage corn (Zea mays L.) and forage during subsequent years of production, but interspecific competition often leads to poor stands of alfalfa and unsatisfactory yields of corn. Four experiments e...

Occurrence of alfalfa (Medicago sativa L.) populations along roadsides in southern Manitoba, Canada and their potential role in intraspecific gene flow.

PubMed

Bagavathiannan, Muthukumar V; Gulden, Robert H; Van Acker, Rene C

2011-04-01

Alfalfa is a highly outcrossing perennial species that can be noticed in roadsides as feral populations. There remains little information available on the extent of feral alfalfa populations in western Canadian prairies and their role in gene flow. The main objectives of this study were (a) to document the occurrence of feral alfalfa populations, and (b) to estimate the levels of outcrossing facilitated by feral populations. A roadside survey confirmed widespread occurrence of feral alfalfa populations, particularly in alfalfa growing regions. The feral populations were dynamic and their frequency ranged from 0.2 to 1.7 populations km(-1). In many cases, the nearest feral alfalfa population from alfalfa production field was located within a distance sufficient for outcrossing in alfalfa. The gene flow study confirmed that genes can move back and forth between feral and cultivated alfalfa populations. In this study, the estimated outcrossing levels were 62% (seed fields to feral), 78% (feral to seed fields), 82% (hay fields to feral) and 85% (feral to feral). Overall, the results show that feral alfalfa plants are prevalent in alfalfa producing regions in western Canada and they can serve as bridges for gene flow at landscape level. Management of feral populations should be considered, if gene flow is a concern. Emphasis on preventing seed spill/escapes and intentional roadside planting of alfalfa cultivars will be particularly helpful. Further, realistic and pragmatic threshold levels should be established for markets sensitive to the presence of GE traits.

Transcriptome responses in alfalfa associated with tolerance to intensive animal grazing

PubMed Central

Wang, Junjie; Zhao, Yan; Ray, Ian; Song, Mingzhou

2016-01-01

Tolerance of alfalfa (Medicago sativa L.) to animal grazing varies widely within the species. However, the molecular mechanisms influencing the grazing tolerant phenotype remain uncharacterized. The objective of this study was to identify genes and pathways that control grazing response in alfalfa. We analyzed whole-plant de novo transcriptomes from grazing tolerant and intolerant populations of M. sativa ssp. falcata subjected to grazing by sheep. Among the Gene Ontology terms which were identified as grazing responsive in the tolerant plants and differentially enriched between the tolerant and intolerant populations (both grazed), most were associated with the ribosome and translation-related activities, cell wall processes, and response to oxygen levels. Twenty-one grazing responsive pathways were identified that also exhibited differential expression between the tolerant and intolerant populations. These pathways were associated with secondary metabolite production, primary carbohydrate metabolic pathways, shikimate derivative dependent pathways, ribosomal subunit composition, hormone signaling, wound response, cell wall formation, and anti-oxidant defense. Sequence polymorphisms were detected among several differentially expressed homologous transcripts between the tolerant and intolerant populations. These differentially responsive genes and pathways constitute potential response mechanisms for grazing tolerance in alfalfa. They also provide potential targets for molecular breeding efforts to develop grazing-tolerant cultivars of alfalfa. PMID:26763747

Migratory Bee Hive Transportation Contributes Insignificantly to Transgenic Pollen Movement Between Spatially Isolated Alfalfa Seed Fields.

PubMed

Boyle, Natalie K; Kesoju, Sandya R; Greene, Stephanie L; Martin, Ruth C; Walsh, Douglas B

2017-02-01

Contracted commercial beekeeping operations provide an essential pollination service to many agricultural systems worldwide. Increased use of genetically engineered crops in agriculture has raised concerns over pollinator-mediated gene flow between transgenic and conventional agricultural varieties. This study evaluated whether contracted migratory beekeeping practices influence transgenic pollen flow among spatially isolated alfalfa fields. Twelve honey bee (Apis mellifera L.) colonies were permitted to forage on transgenic alfalfa blossoms for 1 wk in Touchet, WA. The hives were then transported 112 km to caged conventional alfalfa plots following one and two nights of isolation (8 and 32 h, respectively) from the transgenic source. Alfalfa seed harvested from the conventional plots was assessed for the presence of the transgene using a new seedling germination assay. We found that 8 h of isolation from a transgenic alfalfa source virtually eliminated the incidence of cross-pollination between the two varieties.

Effect of calcium salt of long-chain fatty acids and alfalfa supplementation on performance of Holstein bulls.

PubMed

He, Yang; Niu, Wenjing; Qiu, Qinghua; Xia, Chuanqi; Shao, Taoqi; Wang, Haibo; Li, Qianwen; Yu, Zhantao; Gao, Zhibiao; Rahman, Muhammad Aziz Ur; Su, Huawei; Cao, Binghai

2018-01-09

The purpose of this study was to assess the effects of calcium salt of long-chain fatty acids (CSFA) and alfalfa on beef cattle in the late fattening. 48 Holstein bulls were selected and randomly divided into 4 groups, feeding four dietary that Leymus chinensis with (LC) or with no (LN) 2.4% CSFA, and alfalfa replaced 50% Leymus chinensis with (AC) or with no (AN) 2.4% CSFA. The results indicated that alfalfa improved the feed conversion rate ( P < 0.05). CSFA increased serum low density lipoprotein cholesterol, and reduced the cooking loss of Longissimus muscle ( P < 0.05). CSFA and alfalfa reduced Acetate/Propionate. Alfalfa and CASF had significant additive effects on the apparent digestibility of dry matter, crude protein, neutral detergent fiber, acid detergent fiber, organic matter and rumen fermentation for acetate, isobutyrate, butyrate, isovalerate, total volatile fatty acids ( P < 0.05). CSFA increased microbial diversity index when compared with alfalfa ( P < 0.05), but no significant differences were detected in bacterial genera abundances among diets. The relative abundances of rumen bacterial genera have significant correlation with apparent digestibility of nutrients, rumen fermentation characteristics and serum biochemical parameters ( P < 0.05). These results comprehensively evaluated the additive effects of alfalfa and CSFA on the application in Holstein bulls.

Stress responses in alfalfa (Medicago sativa L. )

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kessmann, H.; Edwards, R.; Dixon, R.A.

1990-09-01

The isoflavonoid conjugates medicarpin-3-O-glucoside-6{double prime}-O-malonate (MGM), afrormosin-7-O-glucoside (AG), and afrormosin-7-O-glucoside-6{double prime}-O-malonate (AGM) were isolated and characterized from cell suspension cultures of alfalfa (Medicago sativa L.), where they were the major constitutive secondary metabolites. They were also found in alfalfa roots but not in other parts of the plant. The phytoalexin medicarpin accumulated rapidly in suspension cultured cells treated with elicitor from Colletotrichum lindemuthianum, and this was subsequently accompanied by an increase in the levels of MGM. In contrast, net accumulation of afrormosin conjugates was not affected by elicitor treatment. Labeling studies with ({sup 14}C)phenylalanine indicated that afrormosin conjugates were themore » major de novo synthesized isoflavonoid products in unelicited cells. During elicitation, ({sup 14}C)phenylalanine was incorporated predominantly into medicarpin, although a significant proportion of the newly synthesized medicarpin was also conjugated. Treatment of {sup 14}C-labeled, elicited cells with L-{alpha}-aminooxy-{beta}-phenylpropionic acid, a potent inhibitor of PAL activity in vivo, resulted in the initial appearance of labeled medicarpin of very low specific activity, suggesting that the phytoalexin could be released from a preformed conjugate under these conditions. Our data draw attention to the involvement of isoflavone hydroxylases during the constitutive and elicitor-induced accumulation of isoflavonoids and their conjugates in alfalfa cell cultures.« less

Economics of growth regulator treatment of alfalfa seed for interseeding into silage corn

USDA-ARS?s Scientific Manuscript database

Previous studies have focused on interseeding of alfalfa into corn for use as a temporary cover crop rather than as a means of jump-starting alfalfa production after corn. In ongoing field studies, we are evaluating whether plant growth regulators (PGR) may be used to aid the establishment of inters...

Alfalfa (Medicago sativa L.) forage production, tissue and soil nutrient concentration under three N based broiler litter regimes

USDA-ARS?s Scientific Manuscript database

Alfalfa (Medicago sativa L.) is considered as most important forage legume grown in Kentucky. Alfalfa supports many livestock production systems including the beef, dairy, and horse industries in Kentucky. Being a legume, alfalfa typically meets its N requirement through symbiotic N2 fixation, but h...

The alfalfa research program in USDA-ARS

USDA-ARS?s Scientific Manuscript database

Alfalfa research is currently conducted by scientists employed by the USDA-Agricultural Research Service (ARS) in nine laboratories located in Minnesota (Saint Paul), Wisconsin (Madison, Prairie du Sac, Marshfield), Maryland (Beltsville), Utah (Logan), Washington (Prosser, Pullman), and Iowa (Ames)....

A kairomone based attract-and-kill system effective against alfalfa looper (Lepidoptera: Noctuidae).

PubMed

Camelo, Leonardo de A; Landolt, Peter J; Zack, Richard S

2007-04-01

A chemical lure derived from flowers that are visited by moths attracts male and female alfalfa loopers, Autographa californica (Speyer) (Lepidoptera: Noctuidae). This feeding attractant is dispensed from polypropylene bottles that provide controlled release for several weeks. A killing station was tested in the laboratory, in a screenhouse, and in the field in combination with this lure as an "attract-and-kill" system. Starved alfalfa looper adults (moths) were strongly attracted to the attract-and-kill station in a flight tunnel, and 90.9% of female moths and 87.6% of male moths that contacted the station died. In commercial fields of alfalfa hay, female moths captured in monitoring traps were reduced by 80-93% in plots receiving 125 attract-and-kill stations per hectare. In screenhouse trials using two attract-and-kill stations per screenhouse, oviposition on potted lettuce plants by starved female alfalfa looper moths was reduced by 98.5%. Moths were less likely to be attracted to lures when provided sugar before flight tunnel assays, and oviposition by fed moths was much less affected by attract-and-kill stations in screenhouse trials, compared with starved moths. This method has potential as a means to manage alfalfa looper populations in vegetable and other agricultural crops. However, consideration must be given to competing food and odor sources in the field.

Interaction of bale size and preservative rate for large-round bales of alfalfa hay

USDA-ARS?s Scientific Manuscript database

Recently, two studies conducted at the US Dairy Forage Research Center have reported inconsistent storage responses following the application of propionic-acid-based preservatives to alfalfa or alfalfa-orchardgrass hays. One of these studies utilized 5-foot-diameter round bales, and produced disappo...

Chloroxyanion residue on seeds and sprouts after chlorine dioxide sanitation of alfalfa seed

USDA-ARS?s Scientific Manuscript database

The effects of a 6-h chlorine dioxide sanitation of alfalfa seed (0, 50, 100, and 200 mg/kg seed) on total coliform bacteria, seed germination, and on the presence of chlorate and perchlorate residues in seed rinse, seed soak, and in alfalfa sprouts was determined. Chlorate residues in 20000 ppm cal...

HI-bearing Ultra Diffuse Galaxies in the ALFALFA Survey

NASA Astrophysics Data System (ADS)

Leisman, Lukas; Janowiecki, Steven; Jones, Michael G.; ALFALFA Almost Darks Team

2018-01-01

The Arecibo Legacy Fast ALFA (Arecibo L-band Feed Array) extragalactic HI survey, with over 30,000 high significance extragalactic sources, is well positioned to locate gas-bearing, low surface brightness sources missed by optical detection algorithms. We investigate the nature of a population of HI-bearing sources in ALFALFA with properties similar to "ultra-diffuse" galaxies (UDGs): galaxies with stellar masses of dwarf galaxies, but radii of L* galaxies. These "HI-bearing ultra-diffuse" sources (HUDS) constitute a small, but pertinent, fraction of the dwarf-mass galaxies in ALFALFA. They are bluer and have more irregular morphologies than the optically-selected UDGs found in clusters, and they appear to be gas-rich for their stellar mass, indicating low star formation efficiency. To illuminate potential explanations for the extreme properties of these sources we explore their environments and estimate their halo properties. We conclude that environmental mechanism are unlikely the cause of HUDS' properties, as they exist in environments equivalent to that of the other ALFALFA sources of similar HI-masses, however, we do find some suggestion that these HUDS may reside in high spin parameter halos, a potential explanation for their "ultra-diffuse" nature.

Effectiveness of neutral detergent fiber in whole cottonseed and dried distillers grains compared with alfalfa haylage.

PubMed

Clark, P W; Armentano, L E

1993-09-01

Sixteen Holstein cows in midlactation were used in a 4 x 4 Latin square design to determine the effect of replacing alfalfa NDF with NDF from whole, linted cottonseed or dried distillers grains. Low and high fiber control diets (13 and 19% of dietary DM from alfalfa haylage NDF, respectively) were compared with diets designed to contain 13% of DM from alfalfa haylage NDF plus 6% of DM from either cottonseed NDF or distillers grains NDF. Dry matter intake, milk yield, and milk protein yield were lower from the high fiber control diet. Milk fat percentage was lower for the low fiber control diet. The cottonseed diet was equal to the high fiber control diet in stimulating rumination. Rumen acetate to propionate ratio was higher for the high fiber control and cottonseed diets. Replacing alfalfa with either of these high fiber by-product feeds increased feed intake and yields of milk fat and protein. The effectiveness of the NDF in distillers grains and cottonseed was not significantly different from that of alfalfa NDF for maintaining milk fat yield. Whole cottonseed and dried distillers grains appear to be good sources of effective fiber for maintaining milk fat test when they are substituted for alfalfa haylage fiber in lactating cow rations.

Influence of summer sowing dates, N fertilization and irrigation on autumn VSP accumulation and dynamics of spring regrowth in alfalfa (Medicago sativa L.).

PubMed

Justes, Eric; Thiébeau, Pascal; Avice, Jean-Christophe; Lemaire, Gilles; Volenec, Jeffrey J; Ourry, Alain

2002-01-01

Herbage yield of alfalfa (Medicago sativa L.) depends on forage management or environmental conditions that change C and N resource acquisition, and endogenous plants factors such as root organic reserves and number of active meristems. The aim of this work is to study the influence of two sowing dates in summer (12 July or 9 August), N fertilization (0 or 100 kg ha(-1)) and/or irrigation applied during the first year of alfalfa establishment on (i) the accumulation of N organic reserves (soluble proteins and more specifically vegetative storage protein) in taproots during autumn, (ii) the number of crown axillary meristems present at the end of winter and (iii) the dynamics of spring shoot growth. Delaying the sowing date for one month reduced root growth and root N storage, especially vegetative storage proteins (VSP) during autumn. Irrespective of sowing dates, N fertilization did not affect root biomass, number of crown buds, total root N, root soluble protein or VSP concentrations. By contrast, water deficiency during alfalfa establishment in the early summer reduced both root growth and N reserve accumulation. When spring growth resumed, there is a significant linear relationship between leaf area development and soluble protein and VSP concentrations in taproots, and also the number of crown buds. The results showed that an early sowing date and adequate water status during the summer allowed alfalfa plants to accumulate N reserves by increasing taproot mass and soluble protein concentrations, especially VSPs. This resulted in rapid shoot regrowth rates the following spring.

Rapid phenotyping of alfalfa root system architecture

USDA-ARS?s Scientific Manuscript database

Root system architecture (RSA) influences the capacity of an alfalfa plant for symbiotic nitrogen fixation, nutrient uptake and water use efficiency, resistance to frost heaving, winterhardiness, and some pest and pathogen resistance. However, we currently lack a basic understanding of root system d...

Complete nucleotide sequence and genome organization of a novel allexivirus from alfalfa (Medicago sativa)

USDA-ARS?s Scientific Manuscript database

A new species of the family Alphaflexiviridae provisionally named Alfalfa virus S (AVS) was diagnosed in alfalfa samples originating from Sudan. A complete nucleotide sequence of the viral genome consisting of 8,349 nucleotides excluding the 3’ poly(A) tail was determined by Illumina NGS technology ...

The impact of lignin downregulation on alfalfa yield, chemical composition, and in vitro gas production.

PubMed

Getachew, Girma; Laca, Emilio A; Putnam, Daniel H; Witte, Dave; McCaslin, Mark; Ortega, Kara P; DePeters, Edward J

2018-02-06

Lignin is a complex, phenolic polymer found in plant cell walls that is essential for mechanical support, water and mineral transport, and defense in vascular plants. Over ten different enzymes play a role in the synthesis of lignin in plants. Suppression of any one enzyme or combinations of these enzymes may change the concentration and composition of lignin in the genetically transformed plants. Two lines of alfalfa that were downregulated for caffeoyl coenzyme A O-methyltransferase were used to assess the impact of lignin downregulation on chemical composition and fermentation rate and extent using an in vitro gas production technique. A total of 64 samples consisting of two reduced lignin (RL) and two controls (CL), four field replicates, two cutting intervals (CIs; 28 and 35 days), and two cuts (Cut-1 and Cut-3) were used. No differences were detected in yield, crude protein, neutral detergent fiber (aNDF), and acid detergent fiber between the lines when harvested at the 28-day CI. The acid detergent lignin (ADL) concentration in RL alfalfa lines was significantly (P < 0.001) lower than in the CL. In alfalfa harvested at the 35-day CI, the RL alfalfa resulted in lower (P < 0.001) yield than CL. RL alfalfa lines had 24% and 22% lower (P < 0.001) ADL in Cut-1 and Cut-3 respectively than CL lines. The in vitro dry matter digestibility and aNDF digestibility (both as determined by the near-infrared reflectance method) were greater (P < 0.001) in RL than in CL lines harvested at the 35-day CI. In alfalfa harvested at the 35-day CI, extent of in vitro gas production and metabolizable energy content were greater in RL than in CL alfalfa. RL lines had 3.8% indigestible aNDF per unit ADL, whereas CL had 3.4% (P < 0.01). The positive effect of lignin downregulation was more pronounced when intervals between harvests were longer (35-day CI compared with the 28-day CI). Lignin downregulation in alfalfa offers an opportunity to extend harvesting time

Proteomic analyses reveal differences in cold acclimation mechanisms in freezing-tolerant and freezing-sensitive cultivars of alfalfa

PubMed Central

Chen, Jing; Han, Guiqing; Shang, Chen; Li, Jikai; Zhang, Hailing; Liu, Fengqi; Wang, Jianli; Liu, Huiying; Zhang, Yuexue

2015-01-01

Cold acclimation in alfalfa (Medicago sativa L.) plays a crucial role in cold tolerance to harsh winters. To examine the cold acclimation mechanisms in freezing-tolerant alfalfa (ZD) and freezing-sensitive alfalfa (W5), holoproteins, and low-abundance proteins (after the removal of RuBisCO) from leaves were extracted to analyze differences at the protein level. A total of 84 spots were selected, and 67 spots were identified. Of these, the abundance of 49 spots and 24 spots in ZD and W5, respectively, were altered during adaptation to chilling stress. Proteomic results revealed that proteins involved in photosynthesis, protein metabolism, energy metabolism, stress and redox and other proteins were mobilized in adaptation to chilling stress. In ZD, a greater number of changes were observed in proteins, and autologous metabolism and biosynthesis were slowed in response to chilling stress, thereby reducing consumption, allowing for homeostasis. The capability for protein folding and protein biosynthesis in W5 was enhanced, which allows protection against chilling stress. The ability to perceive low temperatures was more sensitive in freezing-tolerant alfalfa compared to freezing-sensitive alfalfa. This proteomics study provides new insights into the cold acclimation mechanism in alfalfa. PMID:25774161

Scaling and Predicting the Geotechnical Resistance Provided by Alfalfa in Experimental Studies of Alluvial-Channel Morphology and Planform

NASA Astrophysics Data System (ADS)

Bankhead, N.; Simon, A.

2008-12-01

Several complex interactions occur between riparian vegetation and bank stability processes. Although there are both positive and negative effects of riparian vegetation on streambank stability, a link between increased vegetation density and decreased bank erosion and lateral migration rates of channels has generally been recorded. The ability of vegetation to promote increased bank stability leads to a positive feedback, in which bank stability then allows the growth and establishment of more vegetation. To study interactions between vegetation density and channel planform, past flume studies have used alfalfa sprouts (Medicago sativa), seeded over the entire floodplain in varying densities. Such studies have observed reductions in braiding intensity with increased alfalfa density. It has been assumed in these studies that the alfalfa sprouts increase the resistance of the bank material to lateral erosion. When alfalfa sprouts are scaled up they simulate mature riparian trees well. However, the geotechnical properties of alfalfa roots, and quantification of the increase in resistance provided to the banks under different densities of alfalfa have thus far been ignored. It is therefore unknown if the resistance provided by the alfalfa roots also scales well to real-world root-reinforcement values. To quantify additional bank strength, alfalfa sprouts were grown in sand and the roots tested at regular intervals to measure tensile strength. Results of tensile-strength measurements for alfalfa sprouts displayed the typical non-linear decrease of tensile strength (in MPa) with increasing root diameter. Values for the additional cohesion provided by alfalfa roots were calculated by inputting alfalfa tensile-strength and root density data to the root-reinforcement model, RipRoot, resulting in root-reinforcement values of 0 to 11.8 kPa. These values are similar to those that would be expected under field conditions. The root-cohesion values calculated for alfalfa sprouts

Silicon Priming Created an Enhanced Tolerance in Alfalfa (Medicago sativa L.) Seedlings in Response to High Alkaline Stress.

PubMed

Liu, Duo; Liu, Miao; Liu, Xiao-Long; Cheng, Xian-Guo; Liang, Zheng-Wei

2018-01-01

Alkaline stress as a result of higher pH usually triggers more severe physiological damage to plants than that of saline stress with a neutral pH. In the present study, we demonstrated that silicon (Si) priming of alfalfa ( Medicago sativa L.) seedlings increased their tolerance to high alkaline stress situations. Gongnong No. 1 seedlings were subjected to alkaline stress simulated by 25 mM Na 2 CO 3 (pH 11.2). Alkaline stress greatly decreased the biomass and caused severe lodging or wilting of alfalfa seedlings. In contrast, the application of Si to alfalfa seedlings 36 h prior to the alkaline treatment significantly alleviated the damage symptoms and greatly increased the biomass and chlorophyll content. Because of being concomitant with increasing photosynthesis and water use efficiency, decreasing membrane injury and malondialdehyde content, and increasing peroxidase and catalase ascorbate activities in alfalfa leaves, thereby alleviating the triggered oxidative damage by alkaline stress to the plant. Furthermore, Si priming significantly decreased the accumulation of protein and proline content in alfalfa, thus reducing photosynthetic feedback repression. Si priming significantly accumulated more Na in the roots, but led to a decrease of Na accumulation and an increase of K accumulation in the leaves under alkaline stress. Meanwhile, Si priming decreased the accumulation of metal ions such as Mg, Fe, Mn, and Zn in the roots of alfalfa seedlings under alkaline stress. Collectively, these results suggested that Si is involved in the metabolic or physiological changes and has a potent priming effect on the alkaline tolerance of alfalfa seedlings. The present study indicated that Si priming is a new approach to improve the alkaline tolerance in alfalfa and provides increasing information for further exploration of the alkaline stress response at the molecular level in alfalfa.

Silicon Priming Created an Enhanced Tolerance in Alfalfa (Medicago sativa L.) Seedlings in Response to High Alkaline Stress

PubMed Central

Liu, Duo; Liu, Miao; Liu, Xiao-Long; Cheng, Xian-Guo; Liang, Zheng-Wei

2018-01-01

Alkaline stress as a result of higher pH usually triggers more severe physiological damage to plants than that of saline stress with a neutral pH. In the present study, we demonstrated that silicon (Si) priming of alfalfa (Medicago sativa L.) seedlings increased their tolerance to high alkaline stress situations. Gongnong No. 1 seedlings were subjected to alkaline stress simulated by 25 mM Na2CO3 (pH 11.2). Alkaline stress greatly decreased the biomass and caused severe lodging or wilting of alfalfa seedlings. In contrast, the application of Si to alfalfa seedlings 36 h prior to the alkaline treatment significantly alleviated the damage symptoms and greatly increased the biomass and chlorophyll content. Because of being concomitant with increasing photosynthesis and water use efficiency, decreasing membrane injury and malondialdehyde content, and increasing peroxidase and catalase ascorbate activities in alfalfa leaves, thereby alleviating the triggered oxidative damage by alkaline stress to the plant. Furthermore, Si priming significantly decreased the accumulation of protein and proline content in alfalfa, thus reducing photosynthetic feedback repression. Si priming significantly accumulated more Na in the roots, but led to a decrease of Na accumulation and an increase of K accumulation in the leaves under alkaline stress. Meanwhile, Si priming decreased the accumulation of metal ions such as Mg, Fe, Mn, and Zn in the roots of alfalfa seedlings under alkaline stress. Collectively, these results suggested that Si is involved in the metabolic or physiological changes and has a potent priming effect on the alkaline tolerance of alfalfa seedlings. The present study indicated that Si priming is a new approach to improve the alkaline tolerance in alfalfa and provides increasing information for further exploration of the alkaline stress response at the molecular level in alfalfa. PMID:29896213

Effects of chlorpyrifos and chlorantraniliprole on fermentation quality of alfalfa (Medicago sativa L.) silage inoculated with or without Lactobacillus plantarum LP.

PubMed

Zhang, Qing; Yu, Zhu; Wang, Xianguo; Na, Risu

2017-03-01

The effects of pesticides and Lactobacillus plantarum (LP) on fermentation quality of alfalfa (Medicago sativa L.) silage were investigated. Chlorpyrifos and chlorantraniliprole were sprayed on the surface of alfalfa plants at 658.6 and 45.0 g active ingredient/ha, respectively. Alfalfa plants were harvested on day 5 post-application and ensiled with or without LP. Chlorpyrifos and chlorantraniliprole decreased the yeast count of alfalfa material (P < 0.05). Both pesticides increased the butyric acid content of alfalfa silage (P < 0.001). Chlorpyrifos increased pH and decreased lactic acid, acetic acid and short-chain fatty acid contents (P < 0.05). LP decreased pH and butyric acid content, and increased lactic acid and short-chain fatty acid contents of alfalfa silage treated with pesticides (P < 0.05). LP increased the concentration of chlorpyrifos residue in alfalfa silage (P < 0.05). Chlorpyrifos and chlorantraniliprole affected the microbial communities of the material before ensiling, especially coliform bacteria and yeast; the two pesticide residues were reduced after the fermentation of alfalfa silage and affected the fermentation process, whereas LP improved the fermentation quality of pesticides-contaminated alfalfa silage and slowed down the dissipation of chlorpyrifos. © 2016 Japanese Society of Animal Science.

Substituting oat hay or maize silage for portion of alfalfa hay affects growth performance, ruminal fermentation, and nutrient digestibility of weaned calves

PubMed Central

Zou, Yang; Zou, XinPing; Li, XiZhi; Guo, Gang; Ji, Peng; Wang, Yan; Li, ShengLi; Wang, YaJing; Cao, ZhiJun

2018-01-01

Objective The impact of forage feeding strategy on growth performance, ruminal fermentation and nutrient digestibility in post-weaning calves was investigated. Methods Forty-five female Holstein calves (body weight [BW] = 79.79±0.38 kg) were enrolled in the 35-d study at one week after weaning and randomly assigned to one of three dietary treatments. All diets were fed as total mixed ration containing 60% (dry matter [DM] basis) of basal starter feed and 40% (DM basis) of forage, but varied in composition of forage source including i) alfalfa (40% DM, AH); ii) alfalfa hay (26.7% DM)+oat hay (13.3% DM; OH); iii) alfalfa hay (26.7% DM)+corn silage (13.3% DM; WS). Results Dry matter intake was not different among treatment groups (p>0.05). However, BW (p<0.05) and average daily gain (p<0.05) of calves fed AH and OH were greater than WS-fed calves, whereas heart girth was greater in OH-fed calves than those fed AH and WS (p<0.05). Ruminal fermentation parameters including proportion of butyric acid, acetated-to-propionate ratio, concentration of total volatile fatty acid, protozoal protein, bacterial protein, and microbial protein in rumen were the highest in OH (p<0.05) and the lowest in WS. Compared with the AH and WS, feeding oat hay to postweaning calves increased crude protein digestibility (p<0.05), and decreased duration of diarrhea (p<0.05) and fecal index (p<0.05). Conclusion Our results suggested that partially replacing alfalfa hay with oat hay improved ruminal fermentation, nitrogen utilization, and reduced incidence of diarrhea in post-weaning dairy calves. PMID:28728373

Wrinkled alfalfa seeds harbor more aerobic bacteria and are more difficult to sanitize than smooth seeds.

PubMed

Charkowski, A O; Sarreal, C Z; Mandrell, R E

2001-09-01

At least 14 separate outbreaks of food poisoning attributed to either Salmonella enterica or Escherichia coli O157:H7 have been traced to sprouts in the past decade. Seeds contaminated with human pathogens caused most of these outbreaks, thus many sprout growers are now treating alfalfa seeds with the sanitizing agent, calcium hypochlorite (Ca[OCl]2), prior to sprouting. The efficacy of alfalfa seed sanitation varies between seed lots and between seeds within each lot. Alfalfa seeds from different seed lots were sorted by type in an effort to determine if certain seed types carry more aerobic bacteria than other seed types. Seeds with a wrinkled type, characteristic of lygus bug damage, had significantly higher levels of culturable aerobic bacteria and were more difficult to sanitize than smooth, healthy seeds. After sanitation, wrinkled alfalfa seeds that had been inoculated with S. enterica ser. Newport carried significantly higher levels of Salmonella Newport than smooth seeds. If S. enterica is present on wrinkled seeds in naturally contaminated seed lots, it may be difficult to chemically sanitize the seed lot. Removal of the wrinkled alfalfa seeds from the seed lots, perhaps by adapting color sorting equipment similar to that used to sort rice grains and other seeds, should reduce the level of aerobic bacteria in seed lots and may result in lower levels of human pathogens on contaminated alfalfa seeds.

Removal of toxic heavy metal ions in runoffs by modified alfalfa and juniper

Treesearch

J.S. Han; J.K. Park; S.H. Min

2000-01-01

A series of batch isotherm tests was performed with alfalfa and juniper fibers to evaluate the effectiveness in filtering toxic heavy metals from stormwater. The adsorption of the heavy metal ions on the alfalfa and juniper fibers was strongly dependent on the equilibrium pH value of the solution. The change in sorption rate over time showed that two different sorption...

Effects of residual novaluron on reproduction in alfalfa leafcutting bees, Megachile rotundata F. (Megachilidae).

PubMed

Pitts-Singer, Theresa L; Barbour, James D

2017-01-01

The chitin synthesis inhibitor novaluron can suppress pests that affect alfalfa seed production, but can negatively affect reproductive success in the alfalfa pollinator Megachile rotundata. Novaluron is considered to be a reduced-risk insecticide because it disrupts ecdysis and is non-lethal to adult insects, but some exposed adults have fewer eggs and suppressed egg hatch. For this experiment, bees nested in field cages where they were exposed to alfalfa that had never been treated with novaluron, alfalfa that had recently been sprayed or alfalfa that had been sprayed 1 and 2 weeks earlier. Compared with the control, greater proportions of dead eggs and larvae and lower proportions of live prepupae occurred when bees were exposed to recent novaluron sprays as well as one- or two-week old spray residues. Two possible routes of residual pesticide exposure were revealed. Mother bees become contaminated through ingestion or direct contact, or pollen-nectar provisions become contaminated with novaluron (1) on or within leaf pieces that surround provisions or (2) transferred from mother bees' bodies to provisions. We found strong immature mortality effects of novaluron and its residues on M. rotundata. Understanding all possible pesticide exposure routes for pollinating bees enhances decision-making for maintaining bee populations while protecting crops. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

76 FR 5780 - Determination of Regulated Status of Alfalfa Genetically Engineered for Tolerance to the...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-02

...] Determination of Regulated Status of Alfalfa Genetically Engineered for Tolerance to the Herbicide Glyphosate... for tolerance to the herbicide glyphosate based on APHIS' final environmental impact statement. FOR... regulated status of alfalfa genetically engineered for tolerance to the herbicide glyphosate based on an...

Lignin Modification Leads to Increased Nodule Numbers in Alfalfa1[C][W][OPEN

PubMed Central

Gallego-Giraldo, Lina; Bhattarai, Kishor; Pislariu, Catalina I.; Nakashima, Jin; Jikumaru, Yusuke; Kamiya, Yuji; Udvardi, Michael K.; Monteros, Maria J.; Dixon, Richard A.

2014-01-01

Reduction of lignin levels in the forage legume alfalfa (Medicago sativa) by down-regulation of the monolignol biosynthetic enzyme hydroxycinnamoyl coenzyme A:shikimate hydroxycinnamoyl transferase (HCT) results in strongly increased digestibility and processing ability of lignocellulose. However, these modifications are often also associated with dwarfing and other changes in plant growth. Given the importance of nitrogen fixation for legume growth, we evaluated the impact of constitutively targeted lignin modification on the belowground organs (roots and nodules) of alfalfa plants. HCT down-regulated alfalfa plants exhibit a striking reduction in root growth accompanied by an unexpected increase in nodule numbers when grown in the greenhouse or in the field. This phenotype is associated with increased levels of gibberellins and certain flavonoid compounds in roots. Although HCT down-regulation reduced biomass yields in both the greenhouse and field experiments, the impact on the allocation of nitrogen to shoots or roots was minimal. It is unlikely, therefore, that the altered growth phenotype of reduced-lignin alfalfa is a direct result of changes in nodulation or nitrogen fixation efficiency. Furthermore, HCT down-regulation has no measurable effect on carbon allocation to roots in either greenhouse or 3-year field trials. PMID:24406794

Identification of loci Associated with Resistance to Root-Rot Diseases in Autotetraploid Alfalfa using Genome-Wide Sequencing and Association Mapping

USDA-ARS?s Scientific Manuscript database

Alfalfa (Medicago sativa L.) is the world-wide forage crop. Changing trends to multipurpose uses increases demand for alfalfa. However, the production of alfalfa is challenged by endemic and emerging diseases. Identification of genes/loci controlling disease resistance will facilitate breeding for i...

MicroRNA156 improves drought stress tolerance in alfalfa (Medicago sativa) by silencing SPL13.

PubMed

Arshad, Muhammad; Feyissa, Biruk A; Amyot, Lisa; Aung, Banyar; Hannoufa, Abdelali

2017-05-01

Alfalfa (Medicago sativa) is an important forage crop that is often grown in areas that frequently experience drought and water shortage. MicroRNA156 (miR156) is an emerging tool for improving various traits in plants. We tested the role of miR156d in drought response of alfalfa, and observed a significant improvement in drought tolerance of miR156 overexpression (miR156OE) alfalfa genotypes compared to the wild type control (WT). In addition to higher survival and reduced water loss, miR156OE genotypes also maintained higher stomatal conductance compared to WT during drought stress. Furthermore, we observed an enhanced accumulation of compatible solute (proline) and increased levels of abscisic acid (ABA) and antioxidants in miR156OE genotypes. Similarly, alfalfa plants with reduced expression of miR156-targeted SPL13 showed reduced water loss and enhanced stomatal conductance, chlorophyll content and photosynthetic assimilation. Several genes known to be involved in drought tolerance were differentially expressed in leaf and root of miR156 overexpression plants. Taken together, our findings reveal that miR156 improves drought tolerance in alfalfa at least partially by silencing SPL13. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Accumulation and residue of napropamide in alfalfa (Medicago sativa) and soil involved in toxic response.

PubMed

Cui, Li E; Yang, Hong

2011-06-15

Napropamide belongs to the amide herbicide family and widely used to control weeds in farmland. Intensive use of the herbicide has resulted in widespread contamination to ecosystems. The present study demonstrated an analysis on accumulation of the toxic pesticide napropamide in six genotypes of alfalfa (Medicago sativa), along with biological parameters and its residues in soils. Soil was treated with napropamide at 3 mg kg(-1) dry soil and alfalfa plants were cultured for 10 or 30 d, respectively. The maximum value for napropamide accumulation is 0.426 mg kg(-1) in shoots and 2.444 mg kg(-1) in roots. The napropamide-contaminated soil with alfalfa cultivation had much lower napropamide concentrations than the control (soil without alfalfa cultivation). Also, the content of napropamide residue in the rhizosphere was significantly lower than that in the non-rhizosphere soil. M. sativa exposed to 3 mg kg(-1) napropamide showed inhibited growth. Further analysis revealed that plants treated with napropamide accumulated more reactive oxygen species (O(2)(-) and H(2)O(2)) and less amounts of chlorophyll. However, not all cultivars showed oxidative injury, suggesting that the alfalfa cultivars display different tolerance to napropamide. Copyright © 2011 Elsevier B.V. All rights reserved.

Fermentation, degradation and microbial nitrogen partitioning for three forage colour phenotypes within anthocyanidin-accumulating Lc-alfalfa progeny.

PubMed

Jonker, Arjan; Gruber, Margaret Y; Wang, Yuxi; Narvaez, Nelmy; Coulman, Bruce; McKinnon, John J; Christensen, David A; Azarfar, Arash; Yu, Peiqiang

2012-08-30

Alfalfa has the disadvantage of having a rapid initial rate of protein degradation, which results in pasture bloat, low efficiency of protein utilisation and excessive nitrogen (N) pollution into the environment for cattle. Introducing a gene that stimulates the accumulation of monomeric/polymeric anthocyanidins might reduce the ruminal protein degradation rate (by fixing protein and/or direct interaction with microbes) and additionally reduce methane emission. The objectives of this study were to evaluate in vitro fermentation, degradation and microbial N partitioning of three forage colour phenotypes (green, light purple-green (LPG) and purple-green (PG)) within newly developed Lc-progeny and to compare them with those of parental green non-transgenic (NT) alfalfa. PG-Lc accumulated more anthocyanidin compared with Green-Lc (P < 0.05), with LPG-Lc intermediate. Volatile fatty acids and potentially degradable dry matter (DM) and N were similar among the four phenotypes. Gas, methane and ammonia accumulation rates were slower for the two purple-Lc phenotypes compared with NT-alfalfa (P < 0.05), while Green-Lc was intermediate. Effective degradable DM and N were lower in the three Lc-phenotypes (P < 0.05) compared with NT-alfalfa. Anthocyanidin concentration was negatively correlated (P < 0.05) with gas and methane production rates and effective degradability of DM and N. The Lc-alfalfa phenotypes accumulated anthocyanidin. Fermentation and degradation parameters indicated a reduced rate of fermentation and effective degradability for both purple anthocyanidin-accumulating Lc-alfalfa phenotypes compared with NT-alfalfa. Copyright © 2012 Society of Chemical Industry.

Fixed-Precision Sequential Sampling Plans for Estimating Alfalfa Caterpillar, Colias lesbia, Egg Density in Alfalfa, Medicago sativa, Fields in Córdoba, Argentina

PubMed Central

Serra, Gerardo V.; Porta, Norma C. La; Avalos, Susana; Mazzuferi, Vilma

2013-01-01

The alfalfa caterpillar, Colias lesbia (Fabricius) (Lepidoptera: Pieridae), is a major pest of alfalfa, Medicago sativa L. (Fabales: Fabaceae), crops in Argentina. Its management is based mainly on chemical control of larvae whenever the larvae exceed the action threshold. To develop and validate fixed-precision sequential sampling plans, an intensive sampling programme for C. lesbia eggs was carried out in two alfalfa plots located in the Province of Córdoba, Argentina, from 1999 to 2002. Using Resampling for Validation of Sampling Plans software, 12 additional independent data sets were used to validate the sequential sampling plan with precision levels of 0.10 and 0.25 (SE/mean), respectively. For a range of mean densities of 0.10 to 8.35 eggs/sample, an average sample size of only 27 and 26 sample units was required to achieve a desired precision level of 0.25 for the sampling plans of Green and Kuno, respectively. As the precision level was increased to 0.10, average sample size increased to 161 and 157 sample units for the sampling plans of Green and Kuno, respectively. We recommend using Green's sequential sampling plan because it is less sensitive to changes in egg density. These sampling plans are a valuable tool for researchers to study population dynamics and to evaluate integrated pest management strategies. PMID:23909840

The Arecibo Pisces-Perseus Survey: An Undergraduate ALFALFA Team Project

NASA Astrophysics Data System (ADS)

O'Donoghue, Aileen A.; Koopmann, Rebecca A.; Haynes, Martha P.; Jones, Michael; Craig, David; Hallenbeck, Gregory L.; Rosenberg, Jessica L.; Venkatesan, Aparna; Undergraduate ALFALFA Team

2016-01-01

The Milky Way's position in an outer filament of Lanieakea affords us a striking view of the Pisces-Perseus Supercluster (PPS) arcing roughly from 22h to 4h and 0° to +50° concentrated between cz = 4,000 km/s and cz = 8,000 km/s as a "wall" parallel to the plane of the sky. It is bounded by voids both between Laniakea and PPS and beyond PPS. Within this box, the 70% ALFALFA survey has detected 4,800 galaxies within cz = 8,000 km/s. Of these, 80% have masses greater than 108 M⊙. At the distance of the PPS, galaxies with MHI ≤ 108 M⊙ are below the ALFALFA detection limit. Thus to further explore this rich diversity of galaxy environments and the adjoining voids, the Undergraduate ALFALFA Team is in the process of using the L-band Wide receiver at Arecibo Observatory for the Arecibo Pisces-Perseus Supercluster Survey (APPSS). We will observe galaxies with 108 M⊙ ≤ MHI ≤ 109 M⊙ chosen from the SDSS DR12 and GALEX catalogs. We are limiting our observations to the PPS ridge in 21h 30m to 3h 15m and 23° to 35°. Since this region lacks SDSS spectroscopy, targets have been selected using photometric criteria derived from SDSS and GALEX observations for galaxies detected by ALFALFA. The results of these observations will allow us to constrain the HI mass function along the PPS ridge. Application of the Tully-Fisher relation will allow a robust measure of the infall velocities of galaxies into the filament. This work has been supported by NSF grant AST-1211005.

The Undergraduate ALFALFA Team: A Model for Undergraduate Participation and Outreach in Large Research Collaborations

NASA Astrophysics Data System (ADS)

Martin, A. M.; Koopmann, R.; Higdon, S.; Balonek, T. J.; Haynes, M. P.; Giovanelli, R.; Adams, E. A. K.; Kent, B. R.; Stierwalt, S.

2011-09-01

The Arecibo Legacy Fast ALFA (ALFALFA) blind neutral hydrogen survey is an ongoing project that includes an innovative undergraduate outreach component promoting the participation of students and faculty at undergraduate-focused institutions in a large, multi-year research collaboration. The survey, which will ultimately detect ˜30,000 gas-rich galaxies, provides resources and authentic opportunities for undergraduates and faculty, including a high fraction of women and minorities, through the Undergraduate ALFALFA Team (UAT), an NSF-sponsored consortium of 18 participating institutions. The UAT experience features annual workshops at the Arecibo Observatory with hands-on experience for undergrad participants and their faculty mentors. Graduate students on the Cornell ALFALFA Team help plan and facilitate UAT activities and benefit by developing their own skills as mentors, project supervisors, and science communicators. The UAT is developing online lesson plans and activity guides that make use of the ALFALFA online data archive and of innovative learning techniques supported by the findings of astronomy education research.

Effects of silo type on ensiling alfalfa

USDA-ARS?s Scientific Manuscript database

Various silo types are used on dairy farms, but there is uncertainty as to how silo type affects losses and silage quality. The objective of this study was to compare three silo types, filled with alfalfa from the same fields and emptied simultaneously, relative to filling rates, dry matter (DM) los...

Rhizobia from Lanzarote, the Canary Islands, that nodulate Phaseolus vulgaris have characteristics in common with LMW RNA group II Sinorhizobium meliloti of Medicago, Melilotus and Trigonella from soils of mainland Spain

USDA-ARS?s Scientific Manuscript database

Several isolates from nodules of Phaseolus vulgaris grown in soil of Lanzarote, an island of the Canaries, had electrophoretic LMW RNA patterns identical with a less common pattern within S. meliloti (assigned as group II) obtained from nodules of alfalfa and alfalfa-related legumes grown in northe...

Paternity testing in an autotetraploid alfalfa breeding polycross

USDA-ARS?s Scientific Manuscript database

Determining unknown parentage in autotetraploid alfalfa (Medicago sativa L.) (2n = 4x = 32) can improve breeding gains. Exclusion analysis based paternity testing SAS code is presented, amenable to genotyping errors, for autotetraploid species utilizing co-dominant molecular markers with ambiguous d...

Nitrogen management for first-year corn after alfalfa

USDA-ARS?s Scientific Manuscript database

Rotating alfalfa with corn can increase corn yield potential due to improved soil physical properties that enhance water infiltration and root extension, altered soil microbial communities, and reduced pest pressure. In addition, fertilizer nitrogen (N) requirements are commonly reduced by about 100...

Expression of Anthocyanins and Proanthocyanidins after Transformation of Alfalfa with Maize Lc12

PubMed Central

Ray, Heather; Yu, Min; Auser, Patricia; Blahut-Beatty, Laureen; McKersie, Brian; Bowley, Steve; Westcott, Neil; Coulman, Bruce; Lloyd, Alan; Gruber, Margaret Y.

2003-01-01

Three anthocyanin regulatory genes of maize (Zea mays; Lc, B-Peru, and C1) were introduced into alfalfa (Medicago sativa) in a strategy designed to stimulate the flavonoid pathway and alter the composition of flavonoids produced in forage. Lc constructs included a full-length gene and a gene with a shortened 5′-untranslated region. Lc RNA was strongly expressed in Lc transgenic alfalfa foliage, but accumulation of red-purple anthocyanin was observed only under conditions of high light intensity or low temperature. These stress conditions induced chalcone synthase and flavanone 3-hydroxylase expression in Lc transgenic alfalfa foliage compared with non-transformed plants. Genotypes containing the Lc transgene construct with a full-length 5′-untranslated region responded more quickly to stress conditions and with a more extreme phenotype. High-performance liquid chromatography analysis of field-grown tissue indicated that flavone content was reduced in forage of the Lc transgenic plants. Leucocyanidin reductase, the enzyme that controls entry of metabolites into the proanthocyanidin pathway, was activated both in foliage and in developing seeds of the Lc transgenic alfalfa genotypes. Proanthocyanidin polymer was accumulated in the forage, but (+)-catechin monomers were not detected. B-Peru transgenic and C1 transgenic populations displayed no visible phenotypic changes, although these transgenes were expressed at detectable levels. These results support the emerging picture of Lc transgene-specific patterns of expression in different recipient species. These results demonstrate that proanthocyanidin biosynthesis can be stimulated in alfalfa forage using an myc-like transgene, and they pave the way for the development of high quality, bloat-safe cultivars with ruminal protein bypass. PMID:12857826

Undergraduate ALFALFA Team: Star Formation in the NGC 5846 Group of Galaxies

NASA Astrophysics Data System (ADS)

Viani, Lucas; Koopmann, R. A.; Darling, H.; ALFALFA Team

2013-01-01

We examine gas and star formation properties of galaxies in the NGC 5846 group. Narrowband Halpha and broadband R images for a sample of galaxies were obtained at the KPNO WIYN 0.9m with MOSAIC and the SMARTS 0.9m telescope at CTIO. Neutral hydrogen data from the Arecibo Legacy Fast ALFA (ALFALFA) survey trace the cold neutral gas content. The amounts and extents of star formation in a subsample of galaxies are compared as a function of cold gas content and position in the group. The typical star formation rates and extents of NGC 5846 galaxies are less than those of isolated galaxies and similar to those of galaxies located in the Virgo Cluster and other group environments. This work is part of the Undergraduate ALFALFA (Arecibo Legacy Fast ALFA) Team Groups Project, a collaborative undertaking of faculty and undergraduates at 11 institutions, aimed at investigating properties of galaxy groups surveyed by the ALFALFA blind HI survey.

First report of Fusarium wilt of alfalfa caused by Fusarium oxysporum f. sp. medicaginis in Wisconsin

USDA-ARS?s Scientific Manuscript database

Fusarium wilt, caused by Fusarium oxysporum f. sp. medicaginis, is an economically important vascular disease of alfalfa (Medicago sativa) throughout the world. Alfalfa plants with foliar wilt symptoms and reddish-brown arcs in roots consistent with Fusarium wilt were observed in disease assessment ...

Low-dose cone-beam CT via raw counts domain low-signal correction schemes: Performance assessment and task-based parameter optimization (Part II. Task-based parameter optimization).

PubMed

Gomez-Cardona, Daniel; Hayes, John W; Zhang, Ran; Li, Ke; Cruz-Bastida, Juan Pablo; Chen, Guang-Hong

2018-05-01

Different low-signal correction (LSC) methods have been shown to efficiently reduce noise streaks and noise level in CT to provide acceptable images at low-radiation dose levels. These methods usually result in CT images with highly shift-variant and anisotropic spatial resolution and noise, which makes the parameter optimization process highly nontrivial. The purpose of this work was to develop a local task-based parameter optimization framework for LSC methods. Two well-known LSC methods, the adaptive trimmed mean (ATM) filter and the anisotropic diffusion (AD) filter, were used as examples to demonstrate how to use the task-based framework to optimize filter parameter selection. Two parameters, denoted by the set P, for each LSC method were included in the optimization problem. For the ATM filter, these parameters are the low- and high-signal threshold levels p l and p h ; for the AD filter, the parameters are the exponents δ and γ in the brightness gradient function. The detectability index d' under the non-prewhitening (NPW) mathematical observer model was selected as the metric for parameter optimization. The optimization problem was formulated as an unconstrained optimization problem that consisted of maximizing an objective function d'(P), where i and j correspond to the i-th imaging task and j-th spatial location, respectively. Since there is no explicit mathematical function to describe the dependence of d' on the set of parameters P for each LSC method, the optimization problem was solved via an experimentally measured d' map over a densely sampled parameter space. In this work, three high-contrast-high-frequency discrimination imaging tasks were defined to explore the parameter space of each of the LSC methods: a vertical bar pattern (task I), a horizontal bar pattern (task II), and a multidirectional feature (task III). Two spatial locations were considered for the analysis, a posterior region-of-interest (ROI) located within the noise streaks region

7 CFR 202.44 - Proceedings under section 305(b) to determine whether foreign alfalfa or red clover seed is not...

Code of Federal Regulations, 2010 CFR

2010-01-01

... foreign alfalfa or red clover seed is not adapted for general agricultural use in the United States. 202... Proceedings under section 305(b) to determine whether foreign alfalfa or red clover seed is not adapted for... for the purpose of determining whether seed of alfalfa or red clover from any foreign country or...

7 CFR 202.44 - Proceedings under section 305(b) to determine whether foreign alfalfa or red clover seed is not...

Code of Federal Regulations, 2011 CFR

2011-01-01

... foreign alfalfa or red clover seed is not adapted for general agricultural use in the United States. 202... Proceedings under section 305(b) to determine whether foreign alfalfa or red clover seed is not adapted for... for the purpose of determining whether seed of alfalfa or red clover from any foreign country or...

Overexpression of GsZFP1 enhances salt and drought tolerance in transgenic alfalfa (Medicago sativa L.).

PubMed

Tang, Lili; Cai, Hua; Ji, Wei; Luo, Xiao; Wang, Zhenyu; Wu, Jing; Wang, Xuedong; Cui, Lin; Wang, Yang; Zhu, Yanming; Bai, Xi

2013-10-01

GsZFP1 encodes a Cys2/His2-type zinc-finger protein. In our previous study, when GsZFP1 was heterologously expressed in Arabidopsis, the transgenic Arabidopsis plants exhibited enhanced drought and cold tolerance. However, it is still unknown whether GsZFP1 is also involved in salt stress. GsZFP1 is from the wild legume Glycine soja. Therefore, the aims of this study were to further elucidate the functions of the GsZFP1 gene under salt and drought stress in the forage legume alfalfa and to investigate its biochemical and physiological functions under these stress conditions. Our data showed that overexpression of GsZFP1 in alfalfa resulted in enhanced salt tolerance. Under high salinity stress, greater relative membrane permeability and malondialdehyde (MDA) content were observed and more free proline and soluble sugars accumulated in transgenic alfalfa than in the wild-type (WT) plants; in addition, the transgenic lines accumulated less Na(+) and more K(+) in both the shoots and roots. Overexpression of GsZFP1 also enhanced the drought tolerance of alfalfa. The fold-inductions of stress-responsive marker gene expression, including MtCOR47, MtRAB18, MtP5CS, and MtRD2, were greater in transgenic alfalfa than those of WT under drought stress conditions. In conclusion, the transgenic alfalfa plants generated in this study could be used for farming in salt-affected as well as arid and semi-arid areas. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Combination treatments for killing Escherichia coli O157:H7 on alfalfa, radish, broccoli, and mung bean seeds.

PubMed

Bari, M L; Nei, D; Enomoto, K; Todoriki, S; Kawamoto, S

2009-03-01

In this study, the effectiveness of prolonged dry-heat treatment (50 degrees C) alone or in combination with chemical treatments (1% oxalic acid, 0.03% phytic acid, 50% ethanol, electrolyzed acidic water, and electrolyzed alkaline water) in eliminating Escherichia coli O157:H7 on laboratory-inoculated alfalfa, radish, broccoli, and mung bean seeds was compared with that of dry-heat treatment in combination with irradiation treatment. Dry-heat treatment for 17 or 24 h alone could reduce E. coli O157:H7 numbers to below detectable levels in radish, broccoli, and alfalfa seeds, but was unable to reduce the pathogen numbers to below the detectable level in mung bean seeds. In addition, dry-heat treatment for 17 h plus sanitizer treatments were effective in greatly reducing pathogen populations on radish, broccoli, and alfalfa seeds, without compromising the quality of the sprouts, but these treatments did not eliminate the pathogen from radish and alfalfa seeds. Seventeen hours of dry heat followed by a 1.0-kGy dose of irradiation completely eliminated E. coli O157:H7 from radish and mung bean seeds, whereas only a minimum radiation dose of 0.25 kGy was required to completely eliminate the pathogen from broccoli and alfalfa seeds. Dry heat in combination with radiation doses of up to 1.0 kGy did not negatively impact the seed germination rate or length of alfalfa, broccoli, and radish seeds or the length of alfalfa, broccoli, and radish sprouts, but did decrease the length of mung bean sprouts.

Alfalfa varieties differ markedly in seedling survival when interseeded into corn and treated with prohexadione-calcium

USDA-ARS?s Scientific Manuscript database

Interseeded alfalfa could serve as a dual purpose crop for providing groundcover during silage corn production and forage during subsequent years of production, but this system has been unworkable because competition between the co-planted crops often leads to stand failure of interseeded alfalfa. R...

Selective lignin downregulation leads to constitutive defense response expression in alfalfa (Medicago sativa L.).

PubMed

Gallego-Giraldo, Lina; Jikumaru, Yusuke; Kamiya, Yuji; Tang, Yuhong; Dixon, Richard A

2011-05-01

• Downregulation of hydroxycinnamoyl CoA: shikimate hydroxycinnamoyl transferase (HCT) in alfalfa (Medicago sativa) reduces lignin levels and improves forage quality and saccharification efficiency for bioethanol production. However, the plants have reduced stature. It was previously reported that HCT-down-regulated Arabidopsis have impaired auxin transport, but this has recently been disproved. • To address the basis for the phenotypes of lignin-modified alfalfa, we measured auxin transport, profiled a range of metabolites including flavonoids and hormones, and performed in depth transcriptome analyses. • Auxin transport is unaffected in HCT antisense alfalfa despite increased flavonoid biosynthesis. The plants show increased cytokinin and reduced auxin levels, and gibberellin levels and sensitivity are both reduced. Levels of salicylic, jasmonic and abscisic acids are elevated, associated with massive upregulation of pathogenesis and abiotic stress-related genes and enhanced tolerance to fungal infection and drought. • We suggest that HCT downregulated alfalfa plants exhibit constitutive activation of defense responses, triggered by release of bioactive cell wall fragments and production of hydrogen peroxide as a result of impaired secondary cell wall integrity. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

Development of glyphosate-resistant alfalfa (Medicago sativa L.) upon transformation with the GR79Ms gene encoding 5-enolpyruvylshikimate-3-phosphate synthase.

PubMed

Yi, Dengxia; Ma, Lin; Lin, Min; Li, Cong

2018-07-01

The glyphosate-resistant gene, GR79Ms, was successfully introduced into the genome of alfalfa. The transgenic events may serve as novel germplasm resources in alfalfa breeding. Weed competition can reduce the alfalfa yield, generating new alfalfa germplasm with herbicide resistance is essential. To obtain transgenic alfalfa lines with glyphosate resistance, a new synthetic glyphosate-resistant gene GR79Ms encoding 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) was introduced into alfalfa germplasm by Agrobacterium tumefaciens-mediated transformation. In total, 67 transformants were obtained. PCR and Southern blot analyses confirmed that GR79Ms was successfully inserted into the genome of alfalfa. Reverse transcription-PCR and western blot analyses further demonstrated the expression of GR79Ms and its product, GR79Ms EPSPS. Moreover, two homozygous transgenic lines were developed in the T 2 generation by means of molecular-assisted selection. Herbicide tolerance spray tests showed that the transgenic plants T 0 -GR1, T 0 -GR2, T 0 -GR3 and two homozygous lines were able to tolerate fourfold higher commercial usage of glyphosate than non-transgenic plants.

Population Dynamics of Empoasca fabae (Hemiptera: Cicadellidae) in Central Iowa Alfalfa Fields

PubMed Central

Weiser Erlandson, L. A.; Obrycki, J. J.

2015-01-01

Adults and nymphs of Empoasca fabae Harris (Hemiptera: Cicadellidae) and adults of predatory species in the families Coccinellidae, Anthocoridae, Nabidae, Chrysopidae, and Hemerobiidae were sampled in Iowa alfalfa fields from June to September in 1999 and 2000. The relationship between each predatory taxa and E. fabae was examined using regression analysis. In 2000, all predators were found to be positively correlated with the presence of E. fabae during all periods sampled and most likely contributed to mortality. Orius insidiosus (Say) (Hemiptera: Anthoridae) was the most numerous insect predatory species; population numbers ranged from 0 to 1 and 0.1 to 3.7 adults per 0.25 m2 in 1999 and 2000, respectively. Partial life tables were constructed for E. fabae nymphs for two alfalfa-growing periods. Nymphs were grouped into three age intervals: first and second, third and fourth, and fifth instars. For the first alfalfa growing period examined, E. fabae nymphal mortality was 70% in 1999 and 49% in 2000. During the last growing period of each season (August–September), total nymphal mortality was relatively low (<25%). Adult E. fabae density ranged from 5.4 to 25.6 and 1.4–9.2 per 0.25 m2 in 1999 and 2000, respectively. E. fabae population peaks were similar for each age interval in all growing periods. This study provides further information on the population dynamics of E. fabae and its relationship with select predatory species in Iowa alfalfa fields. PMID:26320260

A mineral seed coating for control of seedling diseases of alfalfa suitable for organic production systems

USDA-ARS?s Scientific Manuscript database

Most alfalfa seed is treated with the systemic fungicide mefenoxam (Apron XL) for control of soilborne seedling diseases. However, Apron XL does not have activity against Aphanomyces euteiches, the causal agent of Aphanomyces root rot (ARR), which is an important component of the alfalfa root rot co...

Effect of synthetic auxin herbicides on seed development and viability in genetically-engineered glyphosate-resistant alfalfa

USDA-ARS?s Scientific Manuscript database

Feral populations of cultivated crops have the potential to function as bridges and reservoirs that contribute to the unwanted movement of novel genetically engineered (GE) traits. Recognizing that feral alfalfa has the potential to lower genetic purity in alfalfa seed production fields when it is g...

[Natural nucleotide polymorphism of the Srlk gene that determines salt stress tolerance in alfalfa (Medicago sativa L)].

PubMed

Vishnevskaia, M S; Pavlov, A V; Dziubenko, E A; Dziubenko, N I; Potokina, E K

2014-04-01

Based on legume genome syntheny, the nucleotide sequence of Srlk gene, key role of which in response to salt stress was demonstrated for the model species Medicago truncatula, was identified in the major forage and siderate crop alfalfa (Medicago sativa). In twelve alfalfa samples originating from regions with contrasting growing conditions, 19 SNPs were revealed in the Srlk gene. For two nonsynonymous SNPs, molecular markers were designed that could be further used to analyze the association between Srlk gene nucleotide polymorphism and the variability in salt stress tolerance among alfalfa cultivars.

Alfalfa response to irrigation from limited water supplies

USDA-ARS?s Scientific Manuscript database

A five-year field study (2007-2011) of irrigated alfalfa production with a limited water supply was conducted in southwest Kansas with two years of above-average precipitation, one year of average precipitation, and two years of below-average precipitation. The irrigation treatments were designed to...

Flavonoids released naturally from alfalfa promote development of symbiotic glomus spores in vitro.

PubMed

Tsai, S M; Phillips, D A

1991-05-01

Because flavonoids from legumes induce transcription of nodulation genes in symbiotic rhizobial bacteria, it is reasonable to test whether these compounds alter the development of vesicular-arbuscular mycorrhizal (VAM) fungi that infect those plants. Quercetin-3-O-galactoside, the dominant flavonoid released naturally from alfalfa (Medicago sativa L.) seeds, promoted spore germination of Glomus etunicatum and Glomus macrocarpum in vitro. Quercetin produced the maximum increases in spore germination, hyphal elongation, and hyphal branching in G. etunicatum at 1 to 2.5 muM concentrations. Two flavonoids exuded from alfalfa roots, 4',7-dihydroxyflavone and 4',7-dihydroxyflavanone, also enhanced spore germination of this fungal species. Formononetin, an isoflavone that is released from stressed alfalfa roots, inhibited germination of both Glomus species. These in vitro results suggest that plant flavonoids may facilitate or regulate the development of VAM symbioses and offer new hope for developing pure, plant-free cultures of VAM fungi.

Monolignol biosynthesis in microsomal preparations from lignifying stems of alfalfa (Medicago sativa L.).

PubMed

Guo, Dianjing; Chen, Fang; Dixon, Richard A

2002-11-01

Microsomal preparations from lignifying stems of alfalfa (Medicago sativa L.) contained coniferaldehyde 5-hydroxylase activity and immunodetectable caffeic acid 3-O-methyltransferase (COMT), and catalyzed the S-adenosyl L-methionine (SAM) dependent methylation of caffeic acid, caffeyl aldehyde and caffeyl alcohol. When supplied with NADPH and SAM, the microsomes converted caffeyl aldehyde to coniferaldehyde, 5-hydroxyconiferaldehyde, and traces of sinapaldehyde. Coniferaldehyde was a better precursor of sinapaldehyde than was 5-hydroxyconiferaldehyde. The alfalfa microsomes could not metabolize 4-coumaric acid, 4-coumaraldehyde, 4-coumaroyl CoA, or ferulic acid. No metabolism of monolignol precursors was observed in microsomal preparations from transgenic alfalfa down-regulated in COMT expression. In most microsomal preparations, the level of the metabolic conversions was independent of added recombinant COMT. Taken together, the data provide only limited support for the concept of metabolic channeling in the biosynthesis of S monolignols via coniferaldehyde.

Effects of cold plasma treatment on alfalfa seed growth under simulated drought stress

NASA Astrophysics Data System (ADS)

Jinkui, FENG; Decheng, WANG; Changyong, SHAO; Lili, ZHANG; Xin, TANG

2018-03-01

The effect of different cold plasma treatments on the germination and seedling growth of alfalfa (Medicago sativa L.) seeds under simulated drought stress conditions was investigated. Polyethyleneglycol-6000 (PEG 6000)with the mass fraction of 0% (purified water), 5%, 10%, and 15% were applied to simulate the drought environment. The alfalfa seeds were treated with 15 different power levels ranged between 0-280 W for 15 s. The germination potential, germination rate, germination index, seedling root length, seedling height, and vigor index were investigated. Results indicated significant differences between treated with proper power and untreated alfalfa seeds. With the increase of treatment power, these indexes mentioned above almost presented bimodal curves. Under the different mass fractions of PEG 6000, results showed that the lower power led to increased germination, and the seedlings presented good adaptability to different drought conditions. Meanwhile, higher power levels resulted in a decreased germination rate. Seeds treated with 40 W resulted in higher germination potential, germination rate, seedling height, root length, and vigor index. Vigor indexes of the treated seeds under different PEG 6000 stresses increased by 38.68%, 43.91%, 74.34%, and 39.20% respectively compared to CK0-0, CK5-0, CK10-0, and CK15-0 (the control sample under 0%, 5%, 10%, and 15% PEG 6000). Therefore, 40 W was regarded as the best treatment in this research. Although the trend indexes of alfalfa seeds treated with the same power were statistically the same under different PEG 6000 stresses, the cold plasma treatment had a significant effect on the adaptability of alfalfa seeds in different drought environments. Thus, this kind of treatment is worth implementing to promote seed growth under drought situations.

Proteomics Analysis of Alfalfa Response to Heat Stress

PubMed Central

Li, Weimin; Wei, Zhenwu; Qiao, Zhihong; Wu, Zinian; Cheng, Lixiang; Wang, Yuyang

2013-01-01

The proteome responses to heat stress have not been well understood. In this study, alfalfa (Medicago sativa L. cv. Huaiyin) seedlings were exposed to 25°C (control) and 40°C (heat stress) in growth chambers, and leaves were collected at 24, 48 and 72 h after treatment, respectively. The morphological, physiological and proteomic processes were negatively affected under heat stress. Proteins were extracted and separated by two-dimensional polyacrylamide gel electrophoresis (2-DE), and differentially expressed protein spots were identified by mass spectrometry (MS). Totally, 81 differentially expressed proteins were identified successfully by MALDI-TOF/TOF. These proteins were categorized into nine classes: including metabolism, energy, protein synthesis, protein destination/storage, transporters, intracellular traffic, cell structure, signal transduction and disease/defence. Five proteins were further analyzed for mRNA levels. The results of the proteomics analyses provide a better understanding of the molecular basis of heat-stress responses in alfalfa. PMID:24324825

Contrasting Strategies of Alfalfa Stem Elongation in Response to Fall Dormancy in Early Growth Stage: The Tradeoff between Internode Length and Internode Number

PubMed Central

Wang, Zongli; Sun, Qizhong

2015-01-01

Fall dormancy (FD) in alfalfa (Medicago sativa L.) can be described using 11 FD ratings, is widely used as an important indicator of stress resistance, productive performance and spring growth. However, the contrasting growth strategies in internode length and internode number in alfalfa cultivars with different FD rating are poorly understood. Here, a growth chamber study was conducted to investigate the effect of FD on plant height, aboveground biomass, internode length, and internode number in alfalfa individuals in the early growth stages. In order to simulate the alfalfa growth environment in the early stage, 11 alfalfa cultivars with FD ratings from one to 11 were chosen and seeded at the greenhouse, and then were transplanted into an artificial growth chamber. The experimental design was a randomized complete block in a split-plot arrangement with three replicates. Plant height, above-ground biomass, internode length, and internode number were measured in early growth stage in all individuals. Our findings showed that plant height and the aboveground biomass of alfalfa did not significantly differ among 11 different FD rated cultivars. Also, internode length and internode number positively affected plant height and the aboveground biomass of alfalfa individuals and the average internode length significantly increased with increasing FD rating. However, internode number tended to sharply decline when the FD rating increased. Moreover, there were no correlations, slightly negative correlations, and strongly negative correlations between internode length and internode number in alfalfa individuals among the three scales, including within-FD ratings, within-FD categories and inter-FD ratings, respectively. Therefore, our results highlighted that contrasting growth strategies in stem elongation were adopted by alfalfa with different FD ratings in the early growth stage. Alfalfa cultivars with a high FD rating have longer internodes, whereas more dormant alfalfa

First report of race 2 of Colletotrichum trifolii causing anthracnose on alfalfa (Medicago sativa) in Wisconsin

USDA-ARS?s Scientific Manuscript database

Anthracnose of alfalfa (Medicago sativa), caused by Colletotrichum trifolii, is widespread in the United States. Three physiological races have been described. Race 1 is reported to be the dominant race that is present wherever alfalfa is grown, while race 2 was reported in a limited area in the Mid...

Relationship of red and photographic infrared spectral radiances to alfalfa biomass, forage water content, percentage canopy cover, and severity of drought stress

NASA Technical Reports Server (NTRS)

Tucker, C. J.; Elgin, J. H., Jr.; Mcmurtrey, J. E., III

1979-01-01

Red and photographic infrared spectral data were collected using a handheld radiometer for two cuttings of alfalfa. Significant linear and non-linear correlation coefficients were found between the spectral variables and plant height, biomass, forage water content, and estimated canopy cover for the earlier alfalfa cutting. The alfalfa of later cutting experienced a period of severe drought stress which limited growth. The spectral variables were found to be highly correlated with the estimated drought scores for this alfalfa cutting.

Molybdate in Rhizobial Seed-Coat Formulations Improves the Production and Nodulation of Alfalfa

PubMed Central

Zhou, Jiqiong; Deng, Bo; Zhang, Yingjun; Cobb, Adam B.; Zhang, Zhao

2017-01-01

Rhizobia-legume symbiosis is the most well researched biological nitrogen fixation system. Coating legume seeds with rhizobia is now a recognized practical measure for improving the production of legume corp. However, the efficacy of some commercial rhizobia inoculants cannot be guaranteed in China due to the low rate of live rhizobia in these products. A greenhouse experiment was conducted to assess the effects of different rhizobial inoculant formulations on alfalfa productivity and nitrogen fixation. Two rhizobia strains, (ACCC17631 and ACCC17676), that are effective partners with alfalfa variety Zhongmu No. 1 were assessed with different concentrations of ammonium molybdate in seed-coat formulations with two different coating adhesives. Our study showed that the growth, nodulation, and nitrogen fixation ability of the plants inoculated with the ACCC17631 rhizobial strain were greatest when the ammonium molybdate application was0.2% of the formulation. An ammonium molybdate concentration of 0.1% was most beneficial to the growth of the plants inoculated with the ACCC17676 rhizobial strain. The sodium carboxymethyl cellulose and sodium alginate, used as coating adhesives, did not have a significant effect on alfalfa biomass and nitrogen fixation. However, the addition of skimmed milk to the adhesive improved nitrogenase activity. These results demonstrate that a new rhizobial seed-coat formulation benefitted alfalfa nodulation and yield. PMID:28099471

Molybdate in Rhizobial Seed-Coat Formulations Improves the Production and Nodulation of Alfalfa.

PubMed

Zhou, Jiqiong; Deng, Bo; Zhang, Yingjun; Cobb, Adam B; Zhang, Zhao

2017-01-01

Rhizobia-legume symbiosis is the most well researched biological nitrogen fixation system. Coating legume seeds with rhizobia is now a recognized practical measure for improving the production of legume corp. However, the efficacy of some commercial rhizobia inoculants cannot be guaranteed in China due to the low rate of live rhizobia in these products. A greenhouse experiment was conducted to assess the effects of different rhizobial inoculant formulations on alfalfa productivity and nitrogen fixation. Two rhizobia strains, (ACCC17631 and ACCC17676), that are effective partners with alfalfa variety Zhongmu No. 1 were assessed with different concentrations of ammonium molybdate in seed-coat formulations with two different coating adhesives. Our study showed that the growth, nodulation, and nitrogen fixation ability of the plants inoculated with the ACCC17631 rhizobial strain were greatest when the ammonium molybdate application was0.2% of the formulation. An ammonium molybdate concentration of 0.1% was most beneficial to the growth of the plants inoculated with the ACCC17676 rhizobial strain. The sodium carboxymethyl cellulose and sodium alginate, used as coating adhesives, did not have a significant effect on alfalfa biomass and nitrogen fixation. However, the addition of skimmed milk to the adhesive improved nitrogenase activity. These results demonstrate that a new rhizobial seed-coat formulation benefitted alfalfa nodulation and yield.

Carbohydrate and lipid spectroscopic molecular structures of different alfalfa hay and their relationship with nutrient availability in ruminants

PubMed Central

Yari, Mojtaba; Valizadeh, Reza; Nnaserian, Abbas Ali; Jonker, Arjan; Yu, Peiqiang

2017-01-01

Objective This study was conducted to determine molecular structures related to carbohydrates and lipid in alfalfa hay cut at early bud, late bud and early flower and in the afternoon and next morning using Fourier transform infrared spectroscopy (FT/IR) and to determine their relationship with alfalfa hay nutrient profile and availability in ruminants. Methods Chemical composition analysis, carbohydrate fractionation, in situ ruminal degradability, and DVE/OEB model were used to measure nutrient profile and availability of alfalfa hay. Univariate analysis, hierarchical cluster analysis (CLA) and principal components analysis (PCA) were conducted to identify FT/IR spectra differences. Results The FT/IR non-structural carbohydrate (NSCHO) to total carbohydrates and NSCHO to structural carbohydrate ratios decreased (p<0.05), while lignin to NSCHO and lipid CH3 symmetric to CH2 symmetric ratios increased with advancing maturity (p<0.05). The FT/IR spectra related to structural carbohydrates, lignin and lipids were distinguished for alfalfa hay at three maturities by PCA and CLA, while FT/IR molecular structures related to carbohydrates and lipids were similar between alfalfa hay cut in the morning and afternoon when analyzed by PCA and CLA analysis. Positive correlations were found for FT/IR NSCHO to total carbohydrate and NSCHO to structural carbohydrate ratios with non-fiber carbohydrate (by wet chemistry), ruminal fast and intermediately degradable carbohydrate fractions and total ruminal degradability of carbohydrates and predicted intestinal nutrient availability in dairy cows (r≥0.60; p<0.05) whereas FT/IR lignin to NSCHO and CH3 to CH2 symmetric stretching ratio had negative correlation with predicted ruminal and intestinal nutrient availability of alfalfa hay in dairy cows (r≥−0.60; p<0.05). Conclusion FT/IR carbohydrate and lipid molecular structures in alfalfa hay changed with advancing maturity from early bud to early flower, but not during the day

Boosting Alfalfa (Medicago sativa L.) Production With Rhizobacteria From Various Plants in Saudi Arabia.

PubMed

Daur, Ihsanullah; Saad, Maged M; Eida, Abdul Aziz; Ahmad, Shakeel; Shah, Zahid Hussain; Ihsan, Muhammad Z; Muhammad, Yasir; Sohrab, Sayed S; Hirt, Heribert

2018-01-01

This study focused on rhizobacteria to promote sustainable crop production in arid regions of Saudi Arabia. The study isolated 17 tightly root-adhering rhizobacteria from various plants at Hada Al Sham in Saudi Arabia. All 17 rhizobacterial isolates were confirmed as plant growth promoting rhizobacteria by classical biochemical tests. Using 16S rDNA gene sequence analyses, the strains were identified as Bacillus, Acinetobacter and Enterobacter . Subsequently, the strains were assessed for their ability to improve the physiology, nutrient uptake, growth, and yield of alfalfa plants grown under desert agriculture conditions. The field trials were conducted in a randomized complete block design. Inoculation of alfalfa with any of these 17 strains improved the relative water content; chlorophyll a; chlorophyll b; carotenoid contents; nitrogen (N), phosphorus, and potassium contents; plant height; leaf-to-stem ratio; and fresh and dry weight. Acinetobacter pittii JD-14 was most effective to increase fresh and dry weight of alfalfa by 41 and 34%, respectively, when compared to non-inoculated control plants. Nevertheless, all strains enhanced crop traits when compared to controls plants, indicating that these desert rhizobacterial strains could be used to develop an eco-friendly biofertilizer for alfalfa and possibly other crop plants to enhance sustainable production in arid regions.

Boosting Alfalfa (Medicago sativa L.) Production With Rhizobacteria From Various Plants in Saudi Arabia

PubMed Central

Daur, Ihsanullah; Saad, Maged M.; Eida, Abdul Aziz; Ahmad, Shakeel; Shah, Zahid Hussain; Ihsan, Muhammad Z.; Muhammad, Yasir; Sohrab, Sayed S.; Hirt, Heribert

2018-01-01

This study focused on rhizobacteria to promote sustainable crop production in arid regions of Saudi Arabia. The study isolated 17 tightly root-adhering rhizobacteria from various plants at Hada Al Sham in Saudi Arabia. All 17 rhizobacterial isolates were confirmed as plant growth promoting rhizobacteria by classical biochemical tests. Using 16S rDNA gene sequence analyses, the strains were identified as Bacillus, Acinetobacter and Enterobacter. Subsequently, the strains were assessed for their ability to improve the physiology, nutrient uptake, growth, and yield of alfalfa plants grown under desert agriculture conditions. The field trials were conducted in a randomized complete block design. Inoculation of alfalfa with any of these 17 strains improved the relative water content; chlorophyll a; chlorophyll b; carotenoid contents; nitrogen (N), phosphorus, and potassium contents; plant height; leaf-to-stem ratio; and fresh and dry weight. Acinetobacter pittii JD-14 was most effective to increase fresh and dry weight of alfalfa by 41 and 34%, respectively, when compared to non-inoculated control plants. Nevertheless, all strains enhanced crop traits when compared to controls plants, indicating that these desert rhizobacterial strains could be used to develop an eco-friendly biofertilizer for alfalfa and possibly other crop plants to enhance sustainable production in arid regions. PMID:29670582

Assessing of the contributions of pod photosynthesis to carbon acquisition of seed in alfalfa (Medicago sativa L.).

PubMed

Zhang, Wenxu; Mao, Peisheng; Li, Yuan; Wang, Mingya; Xia, Fangshan; Wang, Hui

2017-02-07

The distribution of carbon from a branch setting pod in alfalfa was investigated during the seed development of seeds to determine the relative contribution of pod and leaf photoassimilates to the total C balance and to investigate the partitioning of these photoassimilates to other plant organs. A 13 Clabeling procedure was used to label C photoassimilates of pods and leaves in alfalfa, and the Δ 13 C values of a pod, leaves, a section of stem and roots were measured during seed development on day 10, 15, 20 and 25 after labeling of the pod. The results showed that the alfalfa pod had photosynthetic capacity early in the development of seeds, and that pod photosynthesis could provide carbon to alfalfa organs including seeds, pods, leaves, stems and roots, in addition to leaf photosynthesis. Photosynthesis in the pod affected the total C balance of the alfalfa branch with the redistribution of a portion of pod assimilates to other plant organs. The assimilated 13 C of the pod was used for the growth requirements of plant seeds and pods. The requirements for assimilated C came primarily from the young pod in early seed development, with later requirements provided primarily from the leaf.

Evaluation of two supplements for the prevention of alfalfa bloat.

PubMed

Hall, J W; Walker, I; Majak, W

1994-11-01

Poloxalene and a mineral mixture feed supplement patented for the treatment of emphysema, polyarthritis, and other pectin related diseases were tested in two trials for their ability to prevent bloat in cattle fed fresh alfalfa. Each trial had a crossover design using three Jersey steers with rumen fistulas per group. Each trial period continued until the total number of cases of bloat reached > or = 24. Treatments were given at 0800 each day. The mineral mixture was given at 100 g/d and 190 mg/kg body weight per day in the first and second trials, respectively. Poloxalene, which was tested only in the second trial, was given at 23 mg/kg body weight per day. Each group of steers was then fed 200 kg of freshly harvested alfalfa in the vegetative to early bloom stages of growth at 0830. In the first trial, only 69% as many cases of bloat occurred on the mineral mixture as on the control treatment, but no significant difference was detected in the second trial. The potency of the alfalfa may have been higher in the second trial, when forage dry matter was lower, magnesium and soluble nitrogen were higher, and bloat occasionally occurred twice a day. Bloat did not occur when the steers were treated with poloxalene. In these trials, poloxalene was completely effective in preventing bloat, but the mineral mixture was only partially so.

Element accumulation in tall fescue and alfalfa

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stucky, D.J.; Newman, T.S.

This study was initiated to examine the effect of three application rates of dried anaerobically digested sludge on two different soil media on the establishment, yield, duration, and element accumulation in tall fescue and alfalfa. In a greenhouse study, acid strip-mine spoil and agricultural soil were used to compare plant growth in sewage-amended and untreated media. Sludge was applied at 0, 314, and 627 metric tons/hectare to the agricultural soil control and the strip mine spoil. Plant yields were significantly higher for strip-mine spoil amended with 627 metric tons/ha and for agricultural soil amended with 314 and 627 metric tons/ha.more » Concentrations of Mn, Ni, Cd, Zn, and Cu were measured in plants and soils. Concentrations of Mn, Zn, Ni, and Cd in tall fescue and alfalfa grown in strip-mine spoils were higher at higher sludge application rates. Sludge application rate did not affect Cu uptake. Concentrations of Mn, Zn, Ni, and Cd in tall fescue were highest during the 180 toese is the fluctuation in nutrient salt concentrations:agreement of experimental and calculated data is obtton beam.« less

Effects of alfalfa and organic fertilizer on benzo[a]pyrene dissipation in an aged contaminated soil.

PubMed

Fu, Dengqiang; Teng, Ying; Luo, Yongming; Tu, Chen; Li, Shixing; Li, Zhengao; Christie, Peter

2012-06-01

A climate-controlled pot experiment was conducted to investigate the effects of planting alfalfa and applying organic fertilizer on the dissipation of benzo[a]pyrene from an aged contaminated agricultural soil. Short-term planting of alfalfa inhibited the dissipation of benzo[a]pyrene from the soil by 8.9%, and organic fertilizer enhanced benzo[a]pyrene removal from the soil by 11.6% compared with the unplanted and unfertilized treatments, respectively. No significant interaction was observed between alfalfa and organic fertilizer on benzo[a]pyrene dissipation. Sterilization completely inhibited the removal of benzo[a]pyrene from the soil indicating that its degradation by indigenous microorganisms may have been the main mechanism of dissipation. Furthermore, significant positive relationships were observed between benzo[a]pyrene removal and the contents of soil ammonium nitrogen, nitrate nitrogen, and total mineral nitrogen at the end of the experiment, suggesting that competition between plants and microorganisms for nitrogen may have inhibited benzo[a]pyrene dissipation in the rhizosphere of alfalfa and the addition of organic fertilizer may facilitate microbial degradation of benzo[a]pyrene in the soil.

The Undergraduate ALFALFA Groups Project: Development of a Galaxy Environment Index

NASA Astrophysics Data System (ADS)

Crone, Mary; Turner, J.; ALFALFA Team

2010-01-01

The Undergraduate ALFALFA (Arecibo Legacy Fast ALFA) Team Groups Project is a collaborative undertaking of faculty and undergraduates at 8 institutions, aimed at investigating properties of galaxy groups surveyed by the ALFALFA blind HI survey. We present a galaxy environment index designed to reflect local density in the regions surrounding galaxy groups. These regions typically include hundreds of galaxies with optical and HI properties that can be compared with environment. For example, an 8x10 degree region surrounding the group MKW 11 includes 535 galaxies at the group redshift of 0.02, 139 of which are detected in HI. This work has been supported by NSF grants AST-0724918, AST-0725267, and AST-0725380.

Transgene silencing of sucrose synthase in alfalfa (Medicago sativa L.) stem vascular tissue suggests a role for invertase in cell wall cellulose synthesis

USDA-ARS?s Scientific Manuscript database

Alfalfa (Medicago sativa L.) plants were transformed with two constructs: (1) a truncated phosphoenolpyruvate carboxylase promoter isolated from alfalfa nodules (PEPC-4) fused to GUS; and (2) PEPC-4 fused with sucrose synthase (SUS) isolated from alfalfa nodules. Histochemical staining for GUS in st...

EFFECTS OF OZONE AND WATER STRESS ON CANOPY TEMPERATURE, WATER USE, AND WATER USE EFFICIENCY OF ALFALFA

EPA Science Inventory

Ozone (O3) and soil water deficit are two environmental stresses that significantly affect the growth and yield of alfalfa. However, little is known of the responses of field-grown alfalfa to O3, and the effects of the interaction between O3 and water stress on canopy temperature...

Extending ALFALFA in the Direction of the Pisces-Perseus Supercluster with the Arecibo L-Band Wide Receiver

NASA Astrophysics Data System (ADS)

O'Donoghue, Aileen A.; Haynes, Martha P.; Koopmann, Rebecca A.; Jones, Michael G.; Hallenbeck, Gregory L.; Giovanelli, Riccardo; Hoffman, Lyle; Craig, David W.; Undergraduate ALFALFA Team

2017-01-01

We have completed three “Harvesting ALFALFA” Arecibo observing programs in the direction of the Pisces-Perseus Supercluster (PPS) since ALFALFA observations were finished in 2012. The first was to perform follow-up observations on high signal-to-noise (S/N > 6.5) ALFALFA detections needing confirmation and low S/N sources lacking optical counterparts. A few more high S/N objects were observed in the second program along with targets visually selected from the Sloan Digital Sky Survey (SDSS). The third program included low S/N ALFALFA sources having optical counterparts with redshifts that were unknown or differed from the ALFALFA observations. It also included more galaxies selected from SDSS by eye and by Structured Query Language (SQL) searches with parameters intended to select galaxies at the distance of the PPS (~6,000 km/s). We used pointed basic Total-Power Position-Switched Observations in the 1340 - 1430 MHz ALFALFA frequency range. For sources of known redshift, we used the Wideband Arecibo Pulsar Processors (WAPP’s) , while for sources of unknown redshift we utilized a hybrid/dual bandwidth Doppler tracking mode using the Arecibo Interim 50-MHz Correlator with 9-level sampling.Results confirmed that a few high S/N ALFALFA sources are spurious as expected from the work of Saintonge (2007), low S/N ALFALA sources lacking an optical counterpart are all likely to be spurious, but low S/N sources with optical counterparts are generally reliable. Of the optically selected sources, about 80% were detected and tended to be near the distance of the PPS.This work has been supported by NSF grant AST-1211005.

Efficacy of electrolyzed oxidizing water in inactivating Salmonella on alfalfa seeds and sprouts.

PubMed

Kim, Chyer; Hung, Yen-Con; Brackett, Robert E; Lin, Chyi-Shen

2003-02-01

Studies have demonstrated that electrolyzed oxidizing (EO) water is effective in reducing foodborne pathogens on fresh produce. This study was undertaken to determine the efficacy of EO water and two different forms of chlorinated water (chlorine water from Cl2 and Ca(OCl)2 as sources of chlorine) in inactivating Salmonella on alfalfa seeds and sprouts. Tengram sets of alfalfa seeds inoculated with a five-strain cocktail of Salmonella (6.3 x 10(4) CFU/g) were subjected to 90 ml of deionized water (control), EO water (84 mg/liter of active chlorine), chlorine water (84 mg/liter of active chlorine), and Ca(OCl)2 solutions at 90 and 20,000 mg/liter of active chlorine for 10 min at 24 +/- 2 degrees C. The application of EO water, chlorinated water, and 90 mg/liter of Ca(OCl)2 to alfalfa seeds for 10 min reduced initial populations of Salmonella by at least 1.5 log10 CFU/g. For seed sprouting, alfalfa seeds were soaked in the different treatment solutions described above for 3 h. Ca(OCl)2 (20,000 mg/liter of active chlorine) was the most effective treatment in reducing the populations of Salmonella and non-Salmonella microflora (4.6 and 7.0 log10 CFU/g, respectively). However, the use of high concentrations of chlorine generates worker safety concerns. Also, the Ca(OCl)2 treatment significantly reduced seed germination rates (70% versus 90 to 96%). For alfalfa sprouts, higher bacterial populations were recovered from treated sprouts containing seed coats than from sprouts with seed coats removed. The effectiveness of EO water improved when soaking treatments were applied to sprouts in conjunction with sonication and seed coat removal. The combined treatment achieved 2.3- and 1.5-log10 CFU/g greater reductions than EO water alone in populations of Salmonella and non-Salmonella microflora, respectively. This combination treatment resulted in a 3.3-log10 CFU/g greater reduction in Salmonella populations than the control (deionized water) treatment.

(Almost) Dark Galaxies in the ALFALFA Survey: HI-bearing Ultra-Diffuse Galaxies, and Beyond

NASA Astrophysics Data System (ADS)

Leisman, Luke; Haynes, Martha P.; Giovanelli, Riccardo; ALFALFA Almost Darks Team

2017-01-01

Scaling relations between HI and stars in galaxies suggest strong ties between their atomic gas content and star formation laws. The Arecibo Legacy Fast ALFA (ALFALFA) blind extragalactic HI survey is well positioned to locate very low surface brightness sources that lie off these relations, the most extreme of which may fall below optical detection limits. Thus, the ALFALFA (Almost) Darks Project has been investigating extreme outliers from these relations by studying the ~1% of ALFALFA sources without apparent stellar counterparts in major optical surveys. We have obtained deep HI and optical imaging of 25 of these candidate "dark" sources. We find that most "dark" sources are not extreme "(almost) dark" galaxies. A few are rare OH Megamasers, redshifted into the ALFALFA bandpass, and many are part of large galactic plumes, stretching as far as 600 kpc from their host galaxy. However, a small handful of sources appear to be galaxies with extreme stellar systems. We find multiple systems with HI mass to stellar mass ratios an order of magnitude larger than typical gas rich dwarfs. Further, we find an isolated population of HI-bearing "ultra diffuse" galaxies (UDGs), with stellar masses of dwarfs, but HI and optical radii of L* galaxies. We suggest that these sources may be related to recently reported gas poor, quiescent UDGs.

Development of simple sequence repeat markers and diversity analysis in alfalfa (Medicago sativa L.).

PubMed

Wang, Zan; Yan, Hongwei; Fu, Xinnian; Li, Xuehui; Gao, Hongwen

2013-04-01

Efficient and robust molecular markers are essential for molecular breeding in plant. Compared to dominant and bi-allelic markers, multiple alleles of simple sequence repeat (SSR) markers are particularly informative and superior in genetic linkage map and QTL mapping in autotetraploid species like alfalfa. The objective of this study was to enrich SSR markers directly from alfalfa expressed sequence tags (ESTs). A total of 12,371 alfalfa ESTs were retrieved from the National Center for Biotechnology Information. Total 774 SSR-containing ESTs were identified from 716 ESTs. On average, one SSR was found per 7.7 kb of EST sequences. Tri-nucleotide repeats (48.8 %) was the most abundant motif type, followed by di-(26.1 %), tetra-(11.5 %), penta-(9.7 %), and hexanucleotide (3.9 %). One hundred EST-SSR primer pairs were successfully designed and 29 exhibited polymorphism among 28 alfalfa accessions. The allele number per marker ranged from two to 21 with an average of 6.8. The PIC values ranged from 0.195 to 0.896 with an average of 0.608, indicating a high level of polymorphism of the EST-SSR markers. Based on the 29 EST-SSR markers, assessment of genetic diversity was conducted and found that Medicago sativa ssp. sativa was clearly different from the other subspecies. The high transferability of those EST-SSR markers was also found for relative species.

De novo characterization of fall dormant and nondormant alfalfa (Medicago sativa L.) leaf transcriptome and identification of candidate genes related to fall dormancy.

PubMed

Zhang, Senhao; Shi, Yinghua; Cheng, Ningning; Du, Hongqi; Fan, Wenna; Wang, Chengzhang

2015-01-01

Alfalfa (Medicago sativa L.) is one of the most widely cultivated perennial forage legumes worldwide. Fall dormancy is an adaptive character related to the biomass production and winter survival in alfalfa. The physiological, biochemical and molecular mechanisms causing fall dormancy and the related genes have not been well studied. In this study, we sequenced two standard varieties of alfalfa (dormant and non-dormant) at two time points and generated approximately 160 million high quality paired-end sequence reads using sequencing by synthesis (SBS) technology. The de novo transcriptome assembly generated a set of 192,875 transcripts with an average length of 856 bp representing about 165.1 Mb of the alfalfa leaf transcriptome. After assembly, 111,062 (57.6%) transcripts were annotated against the NCBI non-redundant database. A total of 30,165 (15.6%) transcripts were mapped to 323 Kyoto Encyclopedia of Genes and Genomes pathways. We also identified 41,973 simple sequence repeats, which can be used to generate markers for alfalfa, and 1,541 transcription factors were identified across 1,350 transcripts. Gene expression between dormant and non-dormant alfalfa at different time points were performed, and we identified several differentially expressed genes potentially related to fall dormancy. The Gene Ontology and pathways information were also identified. We sequenced and assembled the leaf transcriptome of alfalfa related to fall dormancy, and also identified some genes of interest involved in the fall dormancy mechanism. Thus, our research focused on studying fall dormancy in alfalfa through transcriptome sequencing. The sequencing and gene expression data generated in this study may be used further to elucidate the complete mechanisms governing fall dormancy in alfalfa.

De Novo Characterization of Fall Dormant and Nondormant Alfalfa (Medicago sativa L.) Leaf Transcriptome and Identification of Candidate Genes Related to Fall Dormancy

PubMed Central

Cheng, Ningning; Du, Hongqi; Fan, Wenna; Wang, Chengzhang

2015-01-01

Alfalfa (Medicago sativa L.) is one of the most widely cultivated perennial forage legumes worldwide. Fall dormancy is an adaptive character related to the biomass production and winter survival in alfalfa. The physiological, biochemical and molecular mechanisms causing fall dormancy and the related genes have not been well studied. In this study, we sequenced two standard varieties of alfalfa (dormant and non-dormant) at two time points and generated approximately 160 million high quality paired-end sequence reads using sequencing by synthesis (SBS) technology. The de novo transcriptome assembly generated a set of 192,875 transcripts with an average length of 856 bp representing about 165.1 Mb of the alfalfa leaf transcriptome. After assembly, 111,062 (57.6%) transcripts were annotated against the NCBI non-redundant database. A total of 30,165 (15.6%) transcripts were mapped to 323 Kyoto Encyclopedia of Genes and Genomes pathways. We also identified 41,973 simple sequence repeats, which can be used to generate markers for alfalfa, and 1,541 transcription factors were identified across 1,350 transcripts. Gene expression between dormant and non-dormant alfalfa at different time points were performed, and we identified several differentially expressed genes potentially related to fall dormancy. The Gene Ontology and pathways information were also identified. We sequenced and assembled the leaf transcriptome of alfalfa related to fall dormancy, and also identified some genes of interest involved in the fall dormancy mechanism. Thus, our research focused on studying fall dormancy in alfalfa through transcriptome sequencing. The sequencing and gene expression data generated in this study may be used further to elucidate the complete mechanisms governing fall dormancy in alfalfa. PMID:25799491

Weaned beef calves fed selenium-biofortified alfalfa hay have an enriched nasal microbiota compared with healthy controls.

PubMed

Hall, Jean A; Isaiah, Anitha; Estill, Charles T; Pirelli, Gene J; Suchodolski, Jan S

2017-01-01

Selenium (Se) is an essential trace mineral important for immune function and overall health of cattle. The nasopharyngeal microbiota in cattle plays an important role in overall respiratory health, especially when stresses associated with weaning, transport, and adaptation to a feedlot affect the normal respiratory defenses. Recent evidence suggests that cattle diagnosed with bovine respiratory disease complex have significantly less bacterial diversity. The objective of this study was to determine whether feeding weaned beef calves Se-enriched alfalfa (Medicago sativa) hay for 9 weeks in a preconditioning program prior to entering the feedlot alters nasal microbiota. Recently weaned beef calves (n = 45) were blocked by sex and body weight, randomly assigned to 3 treatment groups with 3 pens of 5 calves per treatment group, and fed an alfalfa hay based diet for 9 weeks. Alfalfa hay was harvested from fields fertilized with sodium selenate at a rate of 0, 45.0 or 89.9 g Se/ha. Blood samples were collected biweekly and analyzed for whole-blood Se concentrations. Nasal swabs were collected during week 9 from one or two calves from each pen (total n = 16). Calculated Se intake from dietary sources was 3.0, 15.6, and 32.2 mg Se/head/day for calves consuming alfalfa hay with Se concentrations of 0.34 to 2.42 and 5.17 mg Se/kg dry matter, respectively. Whole-blood Se concentrations after 8 weeks of feeding Se-fertilized alfalfa hay were dependent upon Se-application rates (0, 45.0, or 89.9 g Se/ha) and were 155, 345, and 504 ng/mL (PLinear < 0.0001). Microbial DNA was extracted from nasal swabs and amplified and sequenced. Alpha rarefaction curves comparing the species richness (observed OTUs) and overall diversity (Chao1, Observed OTU, and Shannon index) between calves fed selenium-biofortified alfalfa hay compared with control calves showed that Se-supplementation tended to be associated with an enriched nasal microbiota. ANOSIM of unweighted UniFrac distances showed

Evaluation of alfalfa-tall fescue mixtures across multiple environments

USDA-ARS?s Scientific Manuscript database

Binary grass-legume mixtures can benefit forage production systems in different ways helping growers cope both with increasing input costs (e.g., N fertilizer, herbicides) and potentially more variable weather. The main objective of this study was to evaluate alfalfa (Medicago sativa L.) and tall f...

Managing puncturevine in alfalfa hay and along field edges

USDA-ARS?s Scientific Manuscript database

Puncturevine (Tribulus terrestris) is a nuisance and difficult to control weed in alfalfa hay field edges and borders. Puncturevine contaminated hay can contain high levels of nitrates and burs can injure mouths of livestock, lowering the value and quality of the hay. Puncturevine is a summer annual...

The alfalfa yield gap: A review of the evidence

USDA-ARS?s Scientific Manuscript database

Knowledge of feasibly attainable crop yields is needed for many purposes, from field-scale management to national policy decisions. For alfalfa (Medicago sativa L.), the most widely used estimates of yield in the US are whole-farm reports from the National Agriculture Statistics Service, which are b...

Identification of molecular markers associated with Verticillium wilt resistance in alfalfa (Medicago sativa L.) using high-resolution melting.

PubMed

Zhang, Tiejun; Yu, Long-Xi; McCord, Per; Miller, David; Bhamidimarri, Suresh; Johnson, David; Monteros, Maria J; Ho, Julie; Reisen, Peter; Samac, Deborah A

2014-01-01

Verticillium wilt, caused by the soilborne fungus, Verticillium alfalfae, is one of the most serious diseases of alfalfa (Medicago sativa L.) worldwide. To identify loci associated with resistance to Verticillium wilt, a bulk segregant analysis was conducted in susceptible or resistant pools constructed from 13 synthetic alfalfa populations, followed by association mapping in two F1 populations consisted of 352 individuals. Simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers were used for genotyping. Phenotyping was done by manual inoculation of the pathogen to replicated cloned plants of each individual and disease severity was scored using a standard scale. Marker-trait association was analyzed by TASSEL. Seventeen SNP markers significantly associated with Verticillium wilt resistance were identified and they were located on chromosomes 1, 2, 4, 7 and 8. SNP markers identified on chromosomes 2, 4 and 7 co-locate with regions of Verticillium wilt resistance loci reported in M. truncatula. Additional markers identified on chromosomes 1 and 8 located the regions where no Verticillium resistance locus has been reported. This study highlights the value of SNP genotyping by high resolution melting to identify the disease resistance loci in tetraploid alfalfa. With further validation, the markers identified in this study could be used for improving resistance to Verticillium wilt in alfalfa breeding programs.

Isolation, taxonomic analysis, and phenotypic characterization of bacterial endophytes present in alfalfa (Medicago sativa) seeds.

PubMed

López, José Luis; Alvarez, Florencia; Príncipe, Analía; Salas, María Eugenia; Lozano, Mauricio Javier; Draghi, Walter Omar; Jofré, Edgardo; Lagares, Antonio

2018-02-10

A growing body of evidence has reinforced the central role of microbiomes in the life of sound multicellular eukaryotes, thus more properly described as true holobionts. Though soil was considered a main source of plant microbiomes, seeds have been shown to be endophytically colonized by microorganisms thus representing natural carriers of a selected microbial inoculum to the young seedlings. In this work we have investigated the type of culturable endophytic bacteria that are carried within surface-sterilized alfalfa seeds. MALDI-TOF analysis revealed the presence of bacteria that belonged to 40 separate genera, distributed within four taxa (Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes). Nonsymbiotic members of the Rhizobiaceae family were also found. The evaluation of nine different in-vitro biochemical activities demonstrated isolates with complex combinations of traits that, upon a Principal-Component-Analysis, could be classified into four phenotypic groups. That isolates from nearly half of the genera identified had been able to colonize alfalfa plants grown under axenic conditions was remarkable. Further analyses should be addressed to investigating the colonization mechanisms of the alfalfa seeds, the evolutionary significance of the alfalfa-seed endophytes, and also how after germination the seed microbiome competes with spermospheric and rhizospheric soil bacteria to colonize newly emerging seedlings. Copyright © 2018 Elsevier B.V. All rights reserved.

Bacterial population dynamics during the ensiling of Medicago sativa (alfalfa) and subsequent exposure to air.

PubMed

McGarvey, J A; Franco, R B; Palumbo, J D; Hnasko, R; Stanker, L; Mitloehner, F M

2013-06-01

To describe, at high resolution, the bacterial population dynamics and chemical transformations during the ensiling of alfalfa and subsequent exposure to air. Samples of alfalfa, ensiled alfalfa and silage exposed to air were collected and their bacterial population structures compared using 16S rRNA gene libraries containing approximately 1900 sequences each. Cultural and chemical analyses were also performed to complement the 16S gene sequence data. Sequence analysis revealed significant differences (P < 0·05) in the bacterial populations at each time point. The alfalfa-derived library contained mostly sequences associated with the Gammaproteobacteria (including the genera: Enterobacter, Erwinia and Pantoea); the ensiled material contained mostly sequences associated with the lactic acid bacteria (LAB) (including the genera: Lactobacillus, Pediococcus and Lactococcus). Exposure to air resulted in even greater percentages of LAB, especially among the genus Lactobacillus, and a significant drop in bacterial diversity. In-depth 16S rRNA gene sequence analysis revealed significant bacterial population structure changes during ensiling and again during exposure to air. This in-depth description of the bacterial population dynamics that occurred during ensiling and simulated feed out expands our knowledge of these processes. © 2013 The Society for Applied Microbiology No claim to US Government works.

Evaluation of two supplements for the prevention of alfalfa bloat.

PubMed Central

Hall, J W; Walker, I; Majak, W

1994-01-01

Poloxalene and a mineral mixture feed supplement patented for the treatment of emphysema, polyarthritis, and other pectin related diseases were tested in two trials for their ability to prevent bloat in cattle fed fresh alfalfa. Each trial had a crossover design using three Jersey steers with rumen fistulas per group. Each trial period continued until the total number of cases of bloat reached > or = 24. Treatments were given at 0800 each day. The mineral mixture was given at 100 g/d and 190 mg/kg body weight per day in the first and second trials, respectively. Poloxalene, which was tested only in the second trial, was given at 23 mg/kg body weight per day. Each group of steers was then fed 200 kg of freshly harvested alfalfa in the vegetative to early bloom stages of growth at 0830. In the first trial, only 69% as many cases of bloat occurred on the mineral mixture as on the control treatment, but no significant difference was detected in the second trial. The potency of the alfalfa may have been higher in the second trial, when forage dry matter was lower, magnesium and soluble nitrogen were higher, and bloat occasionally occurred twice a day. Bloat did not occur when the steers were treated with poloxalene. In these trials, poloxalene was completely effective in preventing bloat, but the mineral mixture was only partially so. PMID:7866960

Chalkbrood Transmission in the Alfalfa Leafcutting Bee: The Impact of Disinfecting Bee Cocoons in Loose Cell Management Systems

USDA-ARS?s Scientific Manuscript database

A good understanding of pathogen transmission in a host population should illuminate methods for disease prevention and control. A case in point for this is the alfalfa leafcutting bee (Megachile rotundata), a solitary bee which is used extensively for pollination of alfalfa grown for seed. Propaga...

Salicornia europaea L. Na⁺/H⁺ antiporter gene improves salt tolerance in transgenic alfalfa (Medicago sativa L.).

PubMed

Zhang, L Q; Niu, Y D; Huridu, H; Hao, J F; Qi, Z; Hasi, A

2014-07-24

In order to obtain a salt-tolerant perennial alfalfa (Medicago sativa L.), we transferred the halophyte Salicornia europaea L. Na(+)/H(+) antiporter gene, SeNHX1, to alfalfa by using the Agrobacterium-mediated transformation method. The transformants were confirmed by both PCR and RT-PCR analyses. Of 197 plants that were obtained after transformation, 36 were positive by PCR analysis using 2 primer pairs for the CaMV35S-SeNHX1 and SeNHX1-Nos fragments; 6 plants survived in a greenhouse. RT-PCR analysis revealed that SeNHX1 was expressed in 5 plants. The resultant transgenic alfalfa had better salt tolerance. After stress treatment for 21 days with 0.6% NaCl, the chlorophyll and MDA contents in transgenic plants were lower, but proline content and SOD, POD, and CAT activities were higher than those in wild-type plants. These results suggest that the salt tolerance of transgenic alfalfa was improved by the overexpression of the SeNHX1 gene.

Cytotoxicity and apoptosis induced by alfalfa (Medicago sativa) leaf extracts in sensitive and multidrug-resistant tumor cells.

PubMed

Gatouillat, Grégory; Magid, Abdulmagid Alabdul; Bertin, Eric; Okiemy-Akeli, Marie-Genevieve; Morjani, Hamid; Lavaud, Catherine; Madoulet, Claudie

2014-01-01

Alfalfa (Medicago sativa) has been used to cure a wide variety of ailments. However, only a few studies have reported its anticancer effects. In this study, extracts were obtained from alfalfa leaves and their cytotoxic effects were assessed on several sensitive and multidrug-resistant tumor cells lines. Using the mouse leukaemia P388 cell line and its doxorubicin-resistant counterpart (P388/DOX), we showed that the inhibition of cell growth induced by alfalfa leaf extracts was mediated through the induction of apoptosis, as evidenced by DNA fragmentation analysis. The execution of programmed cell death was achieved via the activation of caspase-3, leading to PARP cleavage. Fractionation of toluene extract (To-1), the most active extract obtained from crude extract, led to the identification of 3 terpene derivatives and 5 flavonoids. Among them, (-)-medicarpin, (-)-melilotocarpan E, millepurpan, tricin, and chrysoeriol showed cytotoxic effects in P388 as well as P388/DOX cells. These results demonstrate that alfalfa leaf extract may have interesting potential in cancer chemoprevention and therapy.

On-Farm Validation of Alfalfa N Credits to Corn

USDA-ARS?s Scientific Manuscript database

Rotating alfalfa with corn is useful for reducing soil erosion, enhancing soil tilth and carbon storage, reducing weed seedbanks, disrupting the life cycles of disease and insect pests of corn, and supplying nitrogen (N) to the subsequent corn crop. To adjust N fertilizer rates for corn following al...

Identifying OH Imposters in the ALFALFA Neutral Hydrogen Survey

NASA Astrophysics Data System (ADS)

Suess, Katherine A.; Darling, Jeremy; Haynes, Martha P.; Giovanelli, Riccardo

2016-06-01

OH megamasers (OHMs) are rare, luminous molecular masers that are typically observed in (ultra) luminous infrared galaxies and serve as markers of major galaxy mergers. In blind emission line surveys such as the Arecibo Legacy Fast Arecibo L-Band Feed Array (ALFALFA) survey for neutral hydrogen (H I), OHMs at z ˜ 0.2 can mimic z ˜ 0.05 H I lines. We present the results of optical spectroscopy of ambiguous H I detections in the ALFALFA 40 per cent data release detected by the Wide Field Infrared Survey Explorer (WISE) but with uncertain optical counterparts. The optical redshifts, obtained from observations at the Apache Point Observatory, revealed five new OHMs and identified 129 H I optical counterparts. 60 candidates remain ambiguous. The new OHMs are the first detected in a blind spectral line survey. The number of OHMs in ALFALFA is consistent with predictions from the OH luminosity function. Additionally, the mid-infrared magnitudes and colours of the OHM host galaxies found in a blind survey do not seem to differ from those found in previous targeted surveys. This validates the methods used in previous IR-selected OHM surveys and indicates there is no previously unknown OHM-producing population at z ˜ 0.2. We also provide a method for future surveys to separate OH megamasers from 99 per cent of H I line emitters without optical spectroscopy by using WISE infrared colours and magnitudes. Since the fraction of OHMs found in flux-limited H I surveys is expected to increase with the survey's redshift, this selection method can be applied to future flux-limited high-redshift hydrogen surveys.

Construction of two genetic linkage maps in cultivated tetraploid alfalfa (Medicago sativa) using microsatellite and AFLP markers

PubMed Central

Julier, Bernadette; Flajoulot, Sandrine; Barre, Philippe; Cardinet, Gaëlle; Santoni, Sylvain; Huguet, Thierry; Huyghe, Christian

2003-01-01

Background Alfalfa (Medicago sativa) is a major forage crop. The genetic progress is slow in this legume species because of its autotetraploidy and allogamy. The genetic structure of this species makes the construction of genetic maps difficult. To reach this objective, and to be able to detect QTLs in segregating populations, we used the available codominant microsatellite markers (SSRs), most of them identified in the model legume Medicago truncatula from EST database. A genetic map was constructed with AFLP and SSR markers using specific mapping procedures for autotetraploids. The tetrasomic inheritance was analysed in an alfalfa mapping population. Results We have demonstrated that 80% of primer pairs defined on each side of SSR motifs in M. truncatula EST database amplify with the alfalfa DNA. Using a F1 mapping population of 168 individuals produced from the cross of 2 heterozygous parental plants from Magali and Mercedes cultivars, we obtained 599 AFLP markers and 107 SSR loci. All but 3 SSR loci showed a clear tetrasomic inheritance. For most of the SSR loci, the double-reduction was not significant. For the other loci no specific genotypes were produced, so the significant double-reduction could arise from segregation distortion. For each parent, the genetic map contained 8 groups of four homologous chromosomes. The lengths of the maps were 2649 and 3045 cM, with an average distance of 7.6 and 9.0 cM between markers, for Magali and Mercedes parents, respectively. Using only the SSR markers, we built a composite map covering 709 cM. Conclusions Compared to diploid alfalfa genetic maps, our maps cover about 88–100% of the genome and are close to saturation. The inheritance of the codominant markers (SSR) and the pattern of linkage repulsions between markers within each homology group are consistent with the hypothesis of a tetrasomic meiosis in alfalfa. Except for 2 out of 107 SSR markers, we found a similar order of markers on the chromosomes between the

Effects of residual feed intake classification and method of alfalfa processing on ewe intake and growth.

PubMed

Redden, R R; Surber, L M M; Grove, A V; Kott, R W

2014-02-01

The objective of this research was to evaluate the effects of residual feed intake (RFI) determined under ad libitum feeding conditions on DMI and performance of yearling ewes fed either chopped or pelleted alfalfa hay. In Exp. 1, 45 ewe-lambs had ad libitum access to a pelleted grower diet for 63 d and individual DMI was determined using an electronic feed delivery system. Residual feed intake values were assigned to each ewe-lamb as a measure of feed efficiency. Sixteen ewe-lambs with the most positive RFI values were classified as high RFI (inefficient) and 16 ewe-lambs with the most negative RFI values were classified as low RFI (efficient). In Exp. 2, half of the ewes from each efficiency group were placed into 1 of 2 pens and provided ad libitum access to either pelleted or chopped alfalfa hay. Individual DMI was again determined using an electronic feed delivery system. Body weight, LM area (LMA), and 12th-rib back fat thickness (BF) were measured at the beginning and end of both experiments. In Exp. 1, DMI by ewe-lambs in the low RFI group was 9% less (P = 0.01) than by ewe-lambs in the high RFI group (2.21 vs. 2.43 kg/d); however, ADG and initial and final BW, LMA, and BF did not differ (P > 0.27) among RFI groups. In Exp. 2, there were no feed processing × RFI group interactions (P > 0.14) for any trait. By design, RFI values were lower (P < 0.01) by yearling ewes in the low than high RFI group (-0.27 vs. 0.27); however, RFI values did not differ (P = 1.0) between yearling ewes fed chopped versus pelleted alfalfa. Dry matter intake was 22% less (P < 0.01) by yearling ewes in the low than high RFI group (2.5 vs. 3.2 kg/d) and 59% less (P < 0.01) by yearling ewes fed chopped versus pelleted alfalfa (2.2 vs. 3.5 kg/d). Initial and final BW, ADG, and G:F did not differ (P > 0.45) between RFI groups but were greater (P < 0.01) by yearling ewes fed pelleted alfalfa compared to chopped alfalfa. Final LMA did not differ (P = 0.77) between RFI groups, but final

Lignin and Fiber digestibility in Caffeic Acid 3-O-Methyltransferase and Caffeoyl CoA 3-O-Methyltransferase Downregulated Alfalfa

USDA-ARS?s Scientific Manuscript database

Alfalfa (Medicago sativa L.) is one of the most important forages in the United States. Increasing alfalfa fiber digestibility would improve forage management and ration formulation flexibility. Currently, growers and breeders rely on near infrared spectroscopy (NIRS) to predict forage quality tra...

Impact of preceding crop on alfalfa competitiveness with weeds

USDA-ARS?s Scientific Manuscript database

Organic producers would like to include no-till practices in their farming systems. We are seeking to develop a continuous no-till system for organic farming, based on a complex rotation that includes a 3-year sequence of alfalfa. In this study, we evaluated impact of preceding crop on weed infest...

Transgene silencing of sucrose synthase in alfalfa stem vascular tissue by a truncated phosphoenolpyruvate carboxylase: sucrose synthase construct

USDA-ARS?s Scientific Manuscript database

An important role of sucrose synthase (SUS, EC 2.4.1.13) in plants is to provide UDP-glucose needed for cellulose synthesis in cell walls. We examined if over-expressing SUS in alfalfa (Medicago sativa L.) would increase cellulose content of stem cell walls. Alfalfa plants were transformed with two ...

Analysis of physiological and miRNA responses to Pi deficiency in alfalfa (Medicago sativa L.).

PubMed

Li, Zhenyi; Xu, Hongyu; Li, Yue; Wan, Xiufu; Ma, Zhao; Cao, Jing; Li, Zhensong; He, Feng; Wang, Yufei; Wan, Liqiang; Tong, Zongyong; Li, Xianglin

2018-03-01

The induction of miR399 and miR398 and the inhibition of miR156, miR159, miR160, miR171, miR2111, and miR2643 were observed under Pi deficiency in alfalfa. The miRNA-mediated genes involved in basic metabolic process, root and shoot development, stress response and Pi uptake. Inorganic phosphate (Pi) deficiency is known to be a limiting factor in plant development and growth. However, the underlying miRNAs associated with the Pi deficiency-responsive mechanism in alfalfa are unclear. To elucidate the molecular mechanism at the miRNA level, we constructed four small RNA (sRNA) libraries from the roots and shoots of alfalfa grown under normal or Pi-deficient conditions. In the present study, alfalfa plants showed reductions in biomass, photosynthesis, and Pi content and increases in their root-to-shoot ratio and citric, malic, and succinic acid contents under Pi limitation. Sequencing results identified 47 and 44 differentially expressed miRNAs in the roots and shoots, respectively. Furthermore, 909 potential target genes were predicted, and some targets were validated by RLM-RACE assays. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed prominent enrichment in signal transducer activity, binding and basic metabolic pathways for carbohydrates, fatty acids and amino acids; cellular response to hormone stimulus and response to auxin pathways were also enriched. qPCR results verified that the differentially expressed miRNA profile was consistent with sequencing results, and putative target genes exhibited opposite expression patterns. In this study, the miRNAs associated with the response to Pi limitation in alfalfa were identified. In addition, there was an enrichment of miRNA-targeted genes involved in biological regulatory processes such as basic metabolic pathways, root and shoot development, stress response, Pi transportation and citric acid secretion.

Best Phd thesis Prize: Statistical analysis of ALFALFA galaxies: insights in galaxy

NASA Astrophysics Data System (ADS)

Papastergis, E.

2013-09-01

We use the rich dataset of local universe galaxies detected by the ALFALFA 21cm survey to study the statistical properties of gas-bearing galaxies. In particular, we measure the number density of galaxies as a function of their baryonic mass ("baryonic mass function") and rotational velocity ("velocity width function"), and we characterize their clustering properties ("two-point correlation function"). These statistical distributions are determined by both the properties of dark matter on small scales, as well as by the complex baryonic processes through which galaxies form over cosmic time. We interpret the ALFALFA measurements with the aid of publicly available cosmological N-body simulations and we present some key results related to galaxy formation and small-scale cosmology.

Identification of Molecular Markers Associated with Verticillium Wilt Resistance in Alfalfa (Medicago Sativa L.) Using High-Resolution Melting

PubMed Central

Zhang, Tiejun; Yu, Long-Xi; McCord, Per; Miller, David; Bhamidimarri, Suresh; Johnson, David; Monteros, Maria J.; Ho, Julie; Reisen, Peter; Samac, Deborah A.

2014-01-01

Verticillium wilt, caused by the soilborne fungus, Verticillium alfalfae, is one of the most serious diseases of alfalfa (Medicago sativa L.) worldwide. To identify loci associated with resistance to Verticillium wilt, a bulk segregant analysis was conducted in susceptible or resistant pools constructed from 13 synthetic alfalfa populations, followed by association mapping in two F1 populations consisted of 352 individuals. Simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers were used for genotyping. Phenotyping was done by manual inoculation of the pathogen to replicated cloned plants of each individual and disease severity was scored using a standard scale. Marker-trait association was analyzed by TASSEL. Seventeen SNP markers significantly associated with Verticillium wilt resistance were identified and they were located on chromosomes 1, 2, 4, 7 and 8. SNP markers identified on chromosomes 2, 4 and 7 co-locate with regions of Verticillium wilt resistance loci reported in M. truncatula. Additional markers identified on chromosomes 1 and 8 located the regions where no Verticillium resistance locus has been reported. This study highlights the value of SNP genotyping by high resolution melting to identify the disease resistance loci in tetraploid alfalfa. With further validation, the markers identified in this study could be used for improving resistance to Verticillium wilt in alfalfa breeding programs. PMID:25536106

Thermoperiodism synchronizes emergence in the alfalfa leafcutting bee (Hymenoptera: Megachilidae)

USDA-ARS?s Scientific Manuscript database

Alfalfa seed production in the northwestern United States and western Canada is heavily dependent upon the pollinating services of M. rotundata (F.) (Hymenoptera: Megachilidae). Megachile rotundata females nest in cavities either naturally occurring or in artificial nesting blocks. Because of the ph...

Identification of single-nucleotide polymorphic loci associated with biomass yield under water deficit in alfalfa (Medicago sativa L.) using genome-wide sequencing and association mapping

USDA-ARS?s Scientific Manuscript database

Alfalfa is a worldwide grown forage crop and is important due to its high biomass production and nutritional value. However, the production of alfalfa is challenged by adverse environmental stress factors such as drought and other stresses. Developing drought resistance alfalfa is an important breed...

Influence of fresh alfalfa supplementation on fat skatole and indole concentration and chop odour and flavour in lambs grazing a cocksfoot pasture.

PubMed

Devincenzi, T; Prunier, A; Meteau, K; Nabinger, C; Prache, S

2014-12-01

We investigated the influence of the level of fresh alfalfa supplementation on fat skatole and indole concentration and chop sensory attributes in grazing lambs. Four groups of nine male Romane lambs grazing a cocksfoot pasture were supplemented with various levels of alfalfa for at least 60days before slaughter. Perirenal fat skatole concentration was higher for lambs that consumed alfalfa than for those that consumed only cocksfoot. The intensity of 'animal' odour in the lean part of the chop and of 'animal' flavour in both the lean and fat parts of the chop, evaluated by a trained sensory panel, increased from the lowest level of alfalfa supplementation onwards and did not increase further with increasing levels of alfalfa supplementation. The outcome of this study therefore suggests that these sensory attributes may reach a plateau when perirenal fat skatole concentration is in the range 0.16-0.24μg/g of liquid fat. Copyright © 2014. Published by Elsevier Ltd.

Changes in soil physicochemical properties and soil bacterial community in mulberry (Morus alba L.)/alfalfa (Medicago sativa L.) intercropping system.

PubMed

Zhang, Meng-Meng; Wang, Ning; Hu, Yan-Bo; Sun, Guang-Yu

2018-04-01

A better understanding of tree-based intercropping effects on soil physicochemical properties and bacterial community has a potential contribution to improvement of agroforestry productivity and sustainability. In this study, we investigated the effects of mulberry/alfalfa intercropping on soil physicochemical properties and soil bacterial community by MiSeq sequencing of bacterial 16S rRNA gene. The results showed a significant increase in the contents of available nitrogen, available phosphate, available potassium, and total carbon in the rhizosphere soil of the intercropped alfalfa. Sequencing results showed that intercropping improved bacterial richness and diversity of mulberry and alfalfa based on richness estimates and diversity indices. The relative abundances of Proteobacteria, Actinobacteria, and Firmicutes were significantly higher in intercropping mulberry than in monoculture mulberry; and the abundances of Proteobacteria, Bacteroidetes, and Gemmatimonadetes in the intercropping alfalfa were markedly higher than that in monoculture alfalfa. Bacterial taxa with soil nutrients cycling were enriched in the intercropping system. There were higher relative abundances of Bacillus (0.32%), Pseudomonas (0.14%), and Microbacterium (0.07%) in intercropping mulberry soil, and Bradyrhizobium (1.0%), Sphingomonas (0.56%), Pseudomonas (0.18%), Microbacterium (0.15%), Rhizobium (0.09%), Neorhizobium (0.08%), Rhodococcus (0.06%), and Burkholderia (0.04%) in intercropping alfalfa soil. Variance partition analysis showed that planting pattern contributed 26.7% of the total variation of bacterial community, and soil environmental factors explained approximately 56.5% of the total variation. This result indicated that the soil environmental factors were more important than the planting pattern in shaping the bacterial community in the field soil. Overall, mulberry/alfalfa intercropping changed soil bacterial community, which was related to changes in soil total carbon

Molecular Diversity and Population Structure of a Worldwide Collection of Cultivated Tetraploid Alfalfa (Medicago sativa subsp. sativa L.) Germplasm as Revealed by Microsatellite Markers.

PubMed

Qiang, Haiping; Chen, Zhihong; Zhang, Zhengli; Wang, Xuemin; Gao, Hongwen; Wang, Zan

2015-01-01

Information on genetic diversity and population structure of a tetraploid alfalfa collection might be valuable in effective use of the genetic resources. A set of 336 worldwide genotypes of tetraploid alfalfa (Medicago sativa subsp. sativa L.) was genotyped using 85 genome-wide distributed SSR markers to reveal the genetic diversity and population structure in the alfalfa. Genetic diversity analysis identified a total of 1056 alleles across 85 marker loci. The average expected heterozygosity and polymorphism information content values were 0.677 and 0.638, respectively, showing high levels of genetic diversity in the cultivated tetraploid alfalfa germplasm. Comparison of genetic characteristics across chromosomes indicated regions of chromosomes 2 and 3 had the highest genetic diversity. A higher genetic diversity was detected in alfalfa landraces than that of wild materials and cultivars. Two populations were identified by the model-based population structure, principal coordinate and neighbor-joining analyses, corresponding to China and other parts of the world. However, lack of strictly correlation between clustering and geographic origins suggested extensive germplasm exchanges of alfalfa germplasm across diverse geographic regions. The quantitative analysis of the genetic diversity and population structure in this study could be useful for genetic and genomic analysis and utilization of the genetic variation in alfalfa breeding.

Molecular Diversity and Population Structure of a Worldwide Collection of Cultivated Tetraploid Alfalfa (Medicago sativa subsp. sativa L.) Germplasm as Revealed by Microsatellite Markers

PubMed Central

Qiang, Haiping; Chen, Zhihong; Zhang, Zhengli; Wang, Xuemin; Gao, Hongwen; Wang, Zan

2015-01-01

Information on genetic diversity and population structure of a tetraploid alfalfa collection might be valuable in effective use of the genetic resources. A set of 336 worldwide genotypes of tetraploid alfalfa (Medicago sativa subsp. sativa L.) was genotyped using 85 genome-wide distributed SSR markers to reveal the genetic diversity and population structure in the alfalfa. Genetic diversity analysis identified a total of 1056 alleles across 85 marker loci. The average expected heterozygosity and polymorphism information content values were 0.677 and 0.638, respectively, showing high levels of genetic diversity in the cultivated tetraploid alfalfa germplasm. Comparison of genetic characteristics across chromosomes indicated regions of chromosomes 2 and 3 had the highest genetic diversity. A higher genetic diversity was detected in alfalfa landraces than that of wild materials and cultivars. Two populations were identified by the model-based population structure, principal coordinate and neighbor-joining analyses, corresponding to China and other parts of the world. However, lack of strictly correlation between clustering and geographic origins suggested extensive germplasm exchanges of alfalfa germplasm across diverse geographic regions. The quantitative analysis of the genetic diversity and population structure in this study could be useful for genetic and genomic analysis and utilization of the genetic variation in alfalfa breeding. PMID:25901573

Enhanced salt tolerance of alfalfa (Medicago sativa) by rstB gene transformation.

PubMed

Zhang, Wan-Jun; Wang, Tao

2015-05-01

Generating salt tolerance forage plant is essential for use of the land affected by high salinity. A salt tolerance gene rstB was used as a selectable marker gene in Agrobacterium-mediated transformation of tobacco under a selective regime of 170mM NaCl. The transgenic plants showed clear improvement in salt tolerance. To improve salt tolerance of alfalfa (Medicago sativa L.), rstB gene was introduced into alfalfa genome by Agrobacterium-mediated transformation. No abnormal phenotype was observed among the transgenic plants when compared with wild type (wt) plants. Significant enhancement of resistance to salt-shock treatment was noted on the rstB transgenic (T0) plants. Transgenic second-generation (T1) seeds showed improved germination rate and seedling growth under salt-stress condition. Hindered Na(+) accumulation, but enhanced Ca(2+) accumulation was observed on the rstB T1 plants when subjected to salt-stresses. Enhanced calcium accumulation in transgenic plants was also verified by cytohistochemical localization of calcium. Under salt-stress of 50mM NaCl, about 15% of the transgenic plants finished their life-cycle but the wt plants had no flower formation. The results demonstrated that the expression of rstB gene improved salt tolerance in transgenic alfalfa. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Phylogenetic analysis of the alfalfa weevil complex (Coleoptera: Curculionidae) in North America.

PubMed

Böttger, Jorge A Achata; Bundy, C Scott; Oesterle, Naomi; Hanson, Stephen F

2013-02-01

The Eastern, Western, and Egyptian strains of alfalfa weevil are pests introduced to North America on three separate occasions, now they share partially overlapping geographic ranges, covering most of the continental United States. Behavior, susceptibility to parasites, and subtle morphological differences separate the strains. The difficulty in differentiating among these strains morphologically has led to the application of molecular phylogeny approaches including restriction fragment-length polymorphism characterization and sequencing of mitochondrial genes. While valuable for strain identification, this approach cannot identify interstrain hybrids because mitochondrial markers are maternally inherited. The work reported here extends previous findings by comparing over 7 Kb of sequence from two mitochondrial and four nuclear loci to increase the resolution of molecular phylogeny for these weevils. The related clover leaf weevil, also an occasional pest of alfalfa, was included in the analysis because the molecular phylogeny of this weevil has not been examined to date. Analysis of nuclear loci indicate that the clover weevil is a distinct species. Furthermore, while the three alfalfa weevil strains are separable based on mitochondrial sequence data they cannot be separated using nuclearloci suggesting that they are all recently diverged members of the same species. These data refine the relationships among these strains and may find application in design of better control strategies.

Physiological assessment and path coefficient analysis to improve evaluation of alfalfa autotoxicity.

PubMed

Chon, Sang-Uk; Nelson, C Jerry; Coutts, John H

2003-11-01

Reseeding of alfalfa is affected until autotoxic chemicals break down or are dispersed, often requiring a year or more. Bioassays of seed germination and early seedling growth, on agar medium in petri dishes, were conducted to evaluate autotoxic responses of 20 alfalfa germplasms to water-soluble extracts of alfalfa leaf tissue. Root length, 120 hr after placing imbibed seed on agar, was more sensitive to the autotoxin(s) than was hypocotyl length, germination speed, and final germination percentage. Path coefficient analyses showed variation in root length had 7-17 times more effect than variation in hypocotyl length in determining autotoxic effects on total seedling length. Although variations in seed size and germination rate were negatively associated (P < 0.05) with final root length, the autotoxin had little effect on these factors relative to that on root length. Germplasms in the control differed (P < 0.05) in root length, requiring tolerance to be evaluated as percent of control. Germplasms, as percent of control, differed significantly (P < 0.05) at extract concentrations of 1.0 and 4.0 g l(-1), but the range and LSD were more favorable for selection at 1.0 g l(-1). Root length is appropriate for genetic assessments of tolerance to the autotoxin when expressed as percent of control.

Molecular Characterization of Copper Resistance Genes from Xanthomonas citri subsp. citri and Xanthomonas alfalfae subsp. citrumelonis▿

PubMed Central

Behlau, Franklin; Canteros, Blanca I.; Minsavage, Gerald V.; Jones, Jeffrey B.; Graham, James H.

2011-01-01

Copper sprays have been widely used for control of endemic citrus canker caused by Xanthomonas citri subsp. citri in citrus-growing areas for more than 2 decades. Xanthomonas alfalfae subsp. citrumelonis populations were also exposed to frequent sprays of copper for several years as a protective measure against citrus bacterial spot (CBS) in Florida citrus nurseries. Long-term use of these bactericides has led to the development of copper-resistant (Cur) strains in both X. citri subsp. citri and X. alfalfae subsp. citrumelonis, resulting in a reduction of disease control. The objectives of this study were to characterize for the first time the genetics of copper resistance in X. citri subsp. citri and X. alfalfae subsp. citrumelonis and to compare these organisms to other Cur bacteria. Copper resistance determinants from X. citri subsp. citri strain A44(pXccCu2) from Argentina and X. alfalfae subsp. citrumelonis strain 1381(pXacCu2) from Florida were cloned and sequenced. Open reading frames (ORFs) related to the genes copL, copA, copB, copM, copG, copC, copD, and copF were identified in X. citri subsp. citri A44. The same ORFs, except copC and copD, were also present in X. alfalfae subsp. citrumelonis 1381. Transposon mutagenesis of the cloned copper resistance determinants in pXccCu2 revealed that copper resistance in X. citri subsp. citri strain A44 is mostly due to copL, copA, and copB, which are the genes in the cloned cluster with the highest nucleotide homology (≥92%) among different Cur bacteria. PMID:21515725

Expression of a fungal ferulic acid esterase in alfalfa modifies cell wall digestibility

PubMed Central

2014-01-01

Background Alfalfa (Medicago sativa) is an important forage crop in North America owing to its high biomass production, perennial nature and ability to fix nitrogen. Feruloyl esterase (EC 3.1.1.73) hydrolyzes ester linkages in plant cell walls and has the potential to further improve alfalfa as biomass for biofuel production. Results In this study, faeB [GenBank:AJ309807] was synthesized at GenScript and sub-cloned into a novel pEACH vector containing different signaling peptides to target type B ferulic acid esterase (FAEB) proteins to the apoplast, chloroplast, endoplasmic reticulum and vacuole. Four constructs harboring faeB were transiently expressed in Nicotiana leaves, with FAEB accumulating at high levels in all target sites, except chloroplast. Stable transformed lines of alfalfa were subsequently obtained using Agrobacterium tumefaciens (LBA4404). Out of 136 transgenic plants regenerated, 18 independent lines exhibited FAEB activity. Subsequent in vitro digestibility and Fourier transformed infrared spectroscopy (FTIR) analysis of FAEB-expressing lines showed that they possessed modified cell wall morphology and composition with a reduction in ester linkages and elevated lignin content. Consequently, they were more recalcitrant to digestion by mixed ruminal microorganisms. Interestingly, delignification by alkaline peroxide treatment followed by exposure to a commercial cellulase mixture resulted in higher glucose release from transgenic lines as compared to the control line. Conclusion Modifying cell wall crosslinking has the potential to lower recalcitrance of holocellulose, but also exhibited unintended consequences on alfalfa cell wall digestibility due to elevated lignin content. The combination of efficient delignification treatment (alkaline peroxide) and transgenic esterase activity complement each other towards efficient and effective digestion of transgenic lines. PMID:24650274

Effect of Feeding Selenium-Fertilized Alfalfa Hay on Performance of Weaned Beef Calves

PubMed Central

Hall, Jean A.; Bobe, Gerd; Hunter, Janice K.; Vorachek, William R.; Stewart, Whitney C.; Vanegas, Jorge A.; Estill, Charles T.; Mosher, Wayne D.; Pirelli, Gene J.

2013-01-01

Selenium (Se) is an essential micronutrient in cattle, and Se-deficiency can affect morbidity and mortality. Calves may have greater Se requirements during periods of stress, such as during the transitional period between weaning and movement to a feedlot. Previously, we showed that feeding Se-fertilized forage increases whole-blood (WB) Se concentrations in mature beef cows. Our current objective was to test whether feeding Se-fertilized forage increases WB-Se concentrations and performance in weaned beef calves. Recently weaned beef calves (n = 60) were blocked by body weight, randomly assigned to 4 groups, and fed an alfalfa hay based diet for 7 wk, which was harvested from fields fertilized with sodium-selenate at a rate of 0, 22.5, 45.0, or 89.9 g Se/ha. Blood samples were collected weekly and analyzed for WB-Se concentrations. Body weight and health status of calves were monitored during the 7-wk feeding trial. Increasing application rates of Se fertilizer resulted in increased alfalfa hay Se content for that cutting of alfalfa (0.07, 0.95, 1.55, 3.26 mg Se/kg dry matter for Se application rates of 0, 22.5, 45.0, or 89.9 g Se/ha, respectively). Feeding Se-fertilized alfalfa hay during the 7-wk preconditioning period increased WB-Se concentrations (P Linear<0.001) and body weights (P Linear = 0.002) depending upon the Se-application rate. Based upon our results we suggest that soil-Se fertilization is a potential management tool to improve Se-status and performance in weaned calves in areas with low soil-Se concentrations. PMID:23536788

Characterization of alfalfa populations contrasting for root system architecture (RSA)

USDA-ARS?s Scientific Manuscript database

The root system architecture affects the capacity for nutrient and water uptake thus impacting biomass yield production and may contribute to the persistence of perennial plants. The objectives of this study were to phenotype the roots of three alfalfa populations and identify differences between di...

Identification of genetic loci associated with crude protein and mineral concentrations in alfalfa (Medicago sativa) using association mapping.

PubMed

Jia, Congjun; Wu, Xinming; Chen, Min; Wang, Yunqi; Liu, Xiqiang; Gong, Pan; Xu, Qingfang; Wang, Xuemin; Gao, Hongwen; Wang, Zan

2017-06-06

Alfalfa (Medicago sativa) is one of the most important legume forage species in China and many other countries of the world. It provides a quality source of proteins and minerals to animals. Genetic underpinnings for these important traits, however, are elusive. An alfalfa (M. sativa) association mapping study for six traits, namely crude protein (CP), rumen undegraded protein (RUP), and four mineral elements (Ca, K, Mg and P), was conducted in three consecutive years using a large collection encompassing 336 genotypes genotyped with 85 simple sequence repeat (SSR) markers. All the traits were significantly influenced by genotype, environment, and genotype × environment interaction. Eight-five significant associations (P < 0.005) were identified. Among these, five associations with Ca were repeatedly observed and six co-localized associations were identified. The identified marker alleles significantly associated with the traits provided important information for understanding genetic controls of alfalfa quality. The markers could be used in assisting selection for the individual traits in breeding populations for developing new alfalfa cultivars.

Efficacy of chlorine and calcinated calcium treatment of alfalfa seeds and sprouts to eliminate Salmonella.

PubMed

Gandhi, Megha; Matthews, Karl R

2003-11-01

The efficacy of a 20,000 ppm calcium hypochlorite treatment of alfalfa seeds artificially contaminated with Salmonella was studied. Salmonella populations reached >7.0 log on sprouts grown from seeds artificially contaminated with Salmonella and then treated with 20,000 ppm Ca(OCl)(2). The efficacy of spray application of chlorine (100 ppm) to eliminate Salmonella during germination and growth of alfalfa was assessed. Alfalfa seed artificially contaminated with Salmonella was treated at germination, on day 2 or day 4, or for the duration of the growth period. Spray application of 100 ppm chlorine at germination, day 2, or day 4 of growth was minimally effective resulting in approximately a 0.5-log decrease in population of Salmonella. Treatment on each of the 4 days of growth reduced populations of Salmonella by only 1.5 log. Combined treatment of seeds with 20,000 ppm Ca(OCl)(2) and followed by 100 ppm chlorine or calcinated calcium during germination and sprout growth did not eliminate Salmonella.

Gene-Transformation-Induced Changes in Chemical Functional Group Features and Molecular Structure Conformation in Alfalfa Plants Co-Expressing Lc-bHLH and C1-MYB Transcriptive Flavanoid Regulatory Genes: Effects of Single-Gene and Two-Gene Insertion.

PubMed

Heendeniya, Ravindra G; Yu, Peiqiang

2017-03-20

Alfalfa ( Medicago sativa L.) genotypes transformed with Lc-bHLH and Lc transcription genes were developed with the intention of stimulating proanthocyanidin synthesis in the aerial parts of the plant. To our knowledge, there are no studies on the effect of single-gene and two-gene transformation on chemical functional groups and molecular structure changes in these plants. The objective of this study was to use advanced molecular spectroscopy with multivariate chemometrics to determine chemical functional group intensity and molecular structure changes in alfalfa plants when co-expressing Lc-bHLH and C1-MYB transcriptive flavanoid regulatory genes in comparison with non-transgenic (NT) and AC Grazeland (ACGL) genotypes. The results showed that compared to NT genotype, the presence of double genes ( Lc and C1 ) increased ratios of both the area and peak height of protein structural Amide I/II and the height ratio of α-helix to β-sheet. In carbohydrate-related spectral analysis, the double gene-transformed alfalfa genotypes exhibited lower peak heights at 1370, 1240, 1153, and 1020 cm -1 compared to the NT genotype. Furthermore, the effect of double gene transformation on carbohydrate molecular structure was clearly revealed in the principal component analysis of the spectra. In conclusion, single or double transformation of Lc and C1 genes resulted in changing functional groups and molecular structure related to proteins and carbohydrates compared to the NT alfalfa genotype. The current study provided molecular structural information on the transgenic alfalfa plants and provided an insight into the impact of transgenes on protein and carbohydrate properties and their molecular structure's changes.

Increased photosynthetic acclimation in alfalfa associated with arbuscular mycorrhizal fungi (AMF) and cultivated in greenhouse under elevated CO2.

PubMed

Goicoechea, Nieves; Baslam, Marouane; Erice, Gorka; Irigoyen, Juan José

2014-11-15

Medicago sativa L. (alfalfa) can exhibit photosynthetic down-regulation when grown in greenhouse conditions under elevated atmospheric CO2. This forage legume can establish a double symbiosis with nitrogen fixing bacteria and arbuscular mycorrhizal fungi (AMF), which may increase the carbon sink effect of roots. Our aim was to assess whether the association of alfalfa with AMF can avoid, diminish or delay the photosynthetic acclimation observed in previous studies performed with nodulated plants. The results, however, showed that mycorrhizal (M) alfalfa at the end of their vegetative period had lower carbon (C) discrimination than non-mycorrhizal (NM) controls, indicating photosynthetic acclimation under ECO2 in plants associated with AMF. Decreased C discrimination was due to the acclimation of conductance, since the amount of Rubisco and the expression of genes codifying both large and small subunits of Rubisco were similar or slightly higher in M than in NM plants. Moreover, M alfalfa accumulated a greater amount of soluble sugars in leaves than NM plants, thus favoring a down-regulation effect on photosynthetic rates. The enhanced contents of sugars in leaves coincided with a reduced percentage of arbuscules in roots, suggesting decreased sink of carbohydrates from shoots to roots in M plants. The shorter life cycle of alfalfa associated with AMF in comparison with the NM controls may also be related to the accelerated photosynthetic acclimation in M plants. Further research is needed to clarify to what extent this behavior could be extrapolated to alfalfa cultivated in the field and subjected to periodic cutting of shoots under climatic change scenarios. Copyright © 2014 Elsevier GmbH. All rights reserved.

Accounting for alfalfa N credits increases returns to corn production

USDA-ARS?s Scientific Manuscript database

Guidelines are relatively consistent across the Upper Midwest regarding the N benefit of alfalfa to the following grain crops. With higher corn yields and prices, however, some growers have questioned these guidelines and whether more N fertilizer is needed for first-year corn following a good stand...

Geotechnical Implications for the use of Alfalfa in Experimental Studies of Alluvial-Channel Morphology and Planform

NASA Astrophysics Data System (ADS)

Pollen, N.; Simon, A.

2006-12-01

Research on the interactions between vegetation and channel flow dynamics has shown that vegetation is an important control on river morphology and planform. Increased vegetation density is commonly linked to a decrease in bank erosion and lateral migration rates. Roots add to bank strength through the production of a reinforced soil-root matrix, and vegetation can also act to increase bank stability through its hydrological effects, including canopy interception, and removal of soil water through evapotranspiration. Flow dynamics are also affected by vegetation, with a number of studies showing a linkage between vegetation density and width- depth-velocity relations and bank roughness. To evaluate the effects of vegetation on channel morphology and planform, several experimental studies in flumes have used alfalfa sprouts (Medicago sativa) to seed the bed and banks of experimental channels. In such studies, the effects of vegetation are accounted for by qualitatively increasing the resistance of the bank material to lateral erosion. However, the material properties of alfalfa roots and stems, and the actual increase in resistance provided to the banks under different densities of alfalfa have thus far been ignored. To quantify this added erosion resistance, alfalfa sprouts were grown for 7 to 21 days, in sand with a d50 of 0.23 mm. At regular intervals, roots and stems were tested to measure tensile strength and forces required for pullout. Results of the tensile-strength measurements display the typical non-linear decrease of tensile strength (in MPa) with increasing root diameter but the curve is shifted to the left (weaker for a given diameter) of other riparian species. However, to calculate the increase in bank cohesion due to alfalfa roots, it is necessary to also account for the number of roots, and the distribution of different root diameters. The number of roots was calculated for a range of stem densities (0 to 10 stems/cm2), assuming a single, un

Preservation and Faithful Expression of Transgene via Artificial Seeds in Alfalfa

PubMed Central

Liu, Wenting; Liang, Zongsuo; Wang, Xinhua; Sibbald, Susan; Hunter, David; Tian, Lining

2013-01-01

Proper preservation of transgenes and transgenic materials is important for wider use of transgenic technology in plants. Here, we report stable preservation and faithful expression of a transgene via artificial seed technology in alfalfa. DNA constructs containing the uid reporter gene coding for β-glucuronidase (GUS) driven by a 35S promoter or a tCUP promoter were introduced into alfalfa via Agrobacterium-mediated genetic transformation. Somatic embryos were subsequently induced from transgenic alfalfa plants via in vitro technology. These embryos were treated with abscisic acid to induce desiccation tolerance and were subjected to a water loss process. After the desiccation procedure, the water content in dried embryos, or called artificial seeds, was about 12–15% which was equivalent to that in true seeds. Upon water rehydration, the dried somatic embryos showed high degrees of viability and exhibited normal germination. Full plants were subsequently developed and recovered in a greenhouse. The progeny plants developed from artificial seeds showed GUS enzyme activity and the GUS expression level was comparable to that of plants developed from somatic embryos without the desiccation process. Polymerase chain reaction analysis indicated that the transgene was well retained in the plants and Southern blot analysis showed that the transgene was stably integrated in plant genome. The research showed that the transgene and the new trait can be well preserved in artificial seeds and the progeny developed. The research provides a new method for transgenic germplasm preservation in different plant species. PMID:23690914

Star Formation in Undergraduate ALFALFA Team Galaxy Groups and Clusters

NASA Astrophysics Data System (ADS)

Koopmann, Rebecca A.; Durbala, Adriana; Finn, Rose; Haynes, Martha P.; Coble, Kimberly A.; Craig, David W.; Hoffman, G. Lyle; Miller, Brendan P.; Crone-Odekon, Mary; O'Donoghue, Aileen A.; Troischt, Parker; Undergraduate ALFALFA Team; ALFALFA Team

2017-01-01

The Undergraduate ALFALFA Team (UAT) Groups project is a coordinated study of gas and star formation properties of galaxies in and around 36 nearby (z<0.03) groups and clusters of varied richness, morphological type mix, and X-ray luminosity. By studying a large range of environments and considering the spatial distributions of star formation, we probe mechanisms of gas depletion and morphological transformation. The project uses ALFALFA HI observations, optical observations, and digital databases like SDSS, and incorporates work undertaken by faculty and students at different institutions within the UAT. Here we present results from our wide area Hα and broadband R imaging project carried out with the WIYN 0.9m+MOSAIC/HDI at KPNO, including an analysis of radial star formation rates and extents of galaxies in the NGC 5846, Abell 779, NRGb331, and HCG 69 groups/clusters. This work has been supported by NSF grant AST-1211005 and AST-1637339.

Alfalfa and pastures: sources of pests or generalist natural enemies?

USDA-ARS?s Scientific Manuscript database

Pierce’s disease of grapevine and almond leaf scorch disease are both caused by the bacterial pathogen Xyllela fastidiosa. In the Central Valley of California, the green sharpshooter is the most common vector of X. fastidiosa. As alfalfa fields and pastures are considered source habitats for green s...

Transcript analysis in two alfalfa salt tolerance selected breeding populations relative to a non-tolerant population.

PubMed

Gruber, M Y; Xia, J; Yu, M; Steppuhn, H; Wall, K; Messer, D; Sharpe, A G; Acharya, S N; Wishart, D S; Johnson, D; Miller, D R; Taheri, A

2017-02-01

With the growing limitations on arable land, alfalfa (a widely cultivated, low-input forage) is now being selected to extend cultivation into saline lands for low-cost biofeedstock purposes. Here, minerals and transcriptome profiles were compared between two new salinity-tolerant North American alfalfa breeding populations and a more salinity-sensitive western Canadian alfalfa population grown under hydroponic saline conditions. All three populations accumulated two-fold higher sodium in roots than shoots as a function of increased electrical conductivity. At least 50% of differentially expressed genes (p < 0.05) were down-regulated in the salt-sensitive population growing under high salinity, while expression remained unchanged in the saline-tolerant populations. In particular, most reduction in transcript levels in the salt-sensitive population was observed in genes specifying cell wall structural components, lipids, secondary metabolism, auxin and ethylene hormones, development, transport, signalling, heat shock, proteolysis, pathogenesis-response, abiotic stress, RNA processing, and protein metabolism. Transcript diversity for transcription factors, protein modification, and protein degradation genes was also more strongly affected in salt-tolerant CW064027 than in salt-tolerant Bridgeview and salt-sensitive Rangelander, while both saline-tolerant populations showed more substantial up-regulation in redox-related genes and B-ZIP transcripts. The report highlights the first use of bulked genotypes as replicated samples to compare the transcriptomes of obligate out-cross breeding populations in alfalfa.

Intake, digestibility, and composition of orchardgrass and alfalfa silages treated with cellulase, inoculant, and formic acid fed to lambs.

PubMed

Nadeau, E M; Russell, J R; Buxton, D R

2000-11-01

The objectives of this study were to determine the effect of a cellulase (from Trichoderma longibrachiatum) alone or combined with a bacterial inoculant (Lactobacillus plantarum and Pediococcus cerevisiae) or formic acid on composition, intake, and digestibility of orchardgrass (Dactylis glomerata L.) and alfalfa (Medicago sativa L.) silages. Orchardgrass and alfalfa were harvested at the early heading stage and at the early bloom stage of maturity and wilted to approximately 22 and 32% DM, respectively. Forages were then ensiled in 100-L sealed barrels for at least 60 d before they were fed to lambs. Silage treated with cellulase had lower (P < .001) pH and lower (P < .001) acetic acid and NH3 N concentrations than untreated silage of both plant species and a higher (P = .004) lactic acid concentration than the control treatment of alfalfa silage. Fermentation characteristics of cellulase-treated silages, especially of alfalfa, were further enhanced by use of inoculant. Formic acid addition increased (P < .001), reducing sugar concentration of cellulase-treated orchardgrass and alfalfa silage by 90 and 154%, respectively, and decreased (P < .001) NH3 N concentration of cellulase-treated alfalfa silage by 19%. Averaged across plant species, cellulase, combined with inoculant or formic acid, resulted in 8 and 13% greater (P = .03) DMI, respectively, than the control silage. Extensive enzymatic cell-wall degradation during ensiling decreased (P = .003) NDF intake of cellulase-treated orchardgrass silage by 25% and decreased (P = .001) cellulose intake by 23%, when averaged across plant species. Addition of formic acid increased (P = .003) NDF intake of cellulase-treated orchardgrass silage by 19%. Averaged across species, cellulase application decreased (P < .05) silage NDF digestibility by 18%. Greater sugar and lower acetic acid, NH3 N, and NDF concentrations resulted in greater DMI of cellulase-treated silage than of control silage, when cellulase was combined

Comparative analysis of alfalfa (Medicago sativa L.) leaf transcriptomes reveals genotype-specific salt tolerance mechanisms.

PubMed

Lei, Yunting; Xu, Yuxing; Hettenhausen, Christian; Lu, Chengkai; Shen, Guojing; Zhang, Cuiping; Li, Jing; Song, Juan; Lin, Honghui; Wu, Jianqiang

2018-02-15

Soil salinity is an important factor affecting growth, development, and productivity of almost all land plants, including the forage crop alfalfa (Medicago sativa). However, little is known about how alfalfa responds and adapts to salt stress, particularly among different salt-tolerant cultivars. Among seven alfalfa cultivars, we found that Zhongmu-1 (ZM) is relatively salt-tolerant and Xingjiang Daye (XJ) is salt-sensitive. Compared to XJ, ZM showed slower growth under low-salt conditions, but exhibited stronger tolerance to salt stress. RNA-seq analysis revealed 2237 and 1125 differentially expressed genes (DEGs) between ZM and XJ in the presence and absence of salt stress, among which many genes are involved in stress-related pathways. After salt treatment, compared with the controls, the number of DEGs in XJ (19373) was about four times of that in ZM (4833). We also detected specific differential gene expression patterns: In response to salt stress, compared with XJ, ZM maintained relatively more stable expression levels of genes related to the ROS and Ca 2+ pathways, phytohormone biosynthesis, and Na + /K + transport. Notably, several salt resistance-associated genes always showed greater levels of expression in ZM than in XJ, including a transcription factor. Consistent with the suppression of plant growth resulting from salt stress, the expression of numerous photosynthesis- and growth hormone-related genes decreased more dramatically in XJ than in ZM. By contrast, the expression levels of photosynthetic genes were lower in ZM under low-salt conditions. Compared with XJ, ZM is a salt-tolerant alfalfa cultivar possessing specific regulatory mechanisms conferring exceptional salt tolerance, likely by maintaining high transcript levels of abiotic and biotic stress resistance-related genes. Our results suggest that maintaining this specific physiological status and/or plant adaptation to salt stress most likely arises by inhibition of plant growth in ZM through

De Novo Transcriptional Analysis of Alfalfa in Response to Saline-Alkaline Stress.

PubMed

An, Yi-Min; Song, Li-Li; Liu, Ying-Rui; Shu, Yong-Jun; Guo, Chang-Hong

2016-01-01

Saline-alkaline stress, caused by high levels of harmful carbonate salts and high soil pH, is a major abiotic stress that affects crop productivity. Alfalfa is a widely cultivated perennial forage legume with some tolerance to biotic and abiotic stresses, especially to saline-alkaline stress. To elucidate the mechanism underlying plant saline-alkaline tolerance, we conducted transcriptome analysis of whole alfalfa seedlings treated with saline-alkaline solutions for 0 day (control), 1 day (short-term treatment), and 7 days (long-term treatment) using ion torrent sequencing technology. A transcriptome database dataset of 53,853 unigenes was generated, and 2,286 and 2,233 genes were differentially expressed in the short-term and long-term treatment, respectively. Gene ontology analysis revealed 14 highly enriched pathways and demonstrated the differential response of metabolic pathways between the short-term and long-term treatment. The expression levels of 109 and 96 transcription factors were significantly altered significantly after 1 day and 7 days of treatment, respectively. Specific responses of peroxidase, flavonoids, and the light pathway component indicated that the antioxidant capacity was one of the central mechanisms of saline-alkaline stress tolerance response in alfalfa. Among the 18 differentially expressed genes examined by real time PCR, the expression levels of eight genes, including inositol transporter, DNA binding protein, raffinose synthase, ferritin, aldo/keto reductase, glutathione S-transferase, xyloglucan endotrans glucosylase, and a NAC transcription factor, exhibited different patterns in response to saline and alkaline stress. The expression levels of the NAC transcription factor and glutathione S-transferase were altered significantly under saline stress and saline-alkaline stress; they were upregulated under saline-alkaline stress and downregulated under salt stress. Physiology assays showed an increased concentration of reactive oxygen

De Novo Transcriptional Analysis of Alfalfa in Response to Saline-Alkaline Stress

PubMed Central

An, Yi-Min; Song, Li-Li; Liu, Ying-Rui; Shu, Yong-Jun; Guo, Chang-Hong

2016-01-01

Saline-alkaline stress, caused by high levels of harmful carbonate salts and high soil pH, is a major abiotic stress that affects crop productivity. Alfalfa is a widely cultivated perennial forage legume with some tolerance to biotic and abiotic stresses, especially to saline-alkaline stress. To elucidate the mechanism underlying plant saline-alkaline tolerance, we conducted transcriptome analysis of whole alfalfa seedlings treated with saline-alkaline solutions for 0 day (control), 1 day (short-term treatment), and 7 days (long-term treatment) using ion torrent sequencing technology. A transcriptome database dataset of 53,853 unigenes was generated, and 2,286 and 2,233 genes were differentially expressed in the short-term and long-term treatment, respectively. Gene ontology analysis revealed 14 highly enriched pathways and demonstrated the differential response of metabolic pathways between the short-term and long-term treatment. The expression levels of 109 and 96 transcription factors were significantly altered significantly after 1 day and 7 days of treatment, respectively. Specific responses of peroxidase, flavonoids, and the light pathway component indicated that the antioxidant capacity was one of the central mechanisms of saline-alkaline stress tolerance response in alfalfa. Among the 18 differentially expressed genes examined by real time PCR, the expression levels of eight genes, including inositol transporter, DNA binding protein, raffinose synthase, ferritin, aldo/keto reductase, glutathione S-transferase, xyloglucan endotrans glucosylase, and a NAC transcription factor, exhibited different patterns in response to saline and alkaline stress. The expression levels of the NAC transcription factor and glutathione S-transferase were altered significantly under saline stress and saline-alkaline stress; they were upregulated under saline-alkaline stress and downregulated under salt stress. Physiology assays showed an increased concentration of reactive oxygen

Ruminal changes in monensin- and lasalocid-fed cattle grazing bloat-provocative alfalfa pasture.

PubMed

Katz, M P; Nagaraja, T G; Fina, L R

1986-10-01

Microbial and fermentation changes in the rumen in monensin- and lasalocid-fed cattle grazing bloat-provocative alfalfa pasture were studied using genetically bloat-susceptible, ruminally-cannulated adult cattle. Monensin at .66 and .99 mg/kg body weight daily reduced the severity of legume bloat by 41 and 73%, respectively. The same doses of lasalocid reduced bloat by 25 and 12%. Comparison of ruminal contents from animals before treatment with ruminal contents from antibiotic-treated animals showed no differences in pH, ammonia, soluble N, soluble carbohydrate, ethanol-precipitable slime and anaerobic bacterial counts. Monensin treatment decreased protozoal numbers and microbial activity, as evidenced by lower gas production from in vitro fermentation of ground alfalfa hay when compared to pretreatment. Lasalocid had no effect on protozoal counts and in vitro gas production. Addition of monensin or lasalocid (12 micrograms/ml) to in vitro fermentation of chopped, fresh alfalfa reduced microbial activity as evidenced by higher soluble N, lower ammonia concentration and decreased gas production. Monensin reduced the amount of ethanol-precipitable slime and protozoal numbers. Reduction in the severity of bloat when monensin was fed appears to be due to decreased protozoal numbers, which resulted in decreased gas production. Lasalocid did not reduce legume bloat because of its minimal effect on the ruminal protozoa.

A degree-day model of sheep grazing influence on alfalfa weevil and crop characteristics.

PubMed

Goosey, Hayes B

2012-02-01

Domestic sheep (Ovis spp.) grazing is emerging as an integrated pest management tactic for alfalfa weevil, Hypera postica (Gyllenhal), management and a degree-day model is needed as a decision and support tool. In response to this need, grazing exclosures with unique degree-days and stocking rates were established at weekly intervals in a central Montana alfalfa field during 2008 and 2009. Analyses indicate that increased stocking rates and grazing degree-days were associated with decreased crop levels of weevil larvae. Larval data collected from grazing treatments were regressed against on-site and near-site temperatures that produced the same accuracy. The near-site model was chosen to encourage producer acceptance. The regression slope differed from zero, had an r2 of 0.83, and a root mean square error of 0.2. Crop data were collected to achieve optimal weevil management with forage quality and yield. Differences were recorded in crude protein, acid and neutral detergent fibers, total digestible nutrients, and mean stage by weight. Stem heights differed with higher stocking rates and degree-days recording the shortest alfalfa canopy height at harvest. The degree-day model was validated at four sites during 2010 with a mean square prediction error of 0.74. The recommendation from this research is to stock alfalfa fields in the spring before 63 DD with rates between 251 and 583 sheep days per hectare (d/ha). Sheep should be allowed to graze to a minimum of 106 and maximum of 150 DD before removal. This model gives field entomologists a new method for implementing grazing in an integrated pest management program.

Genotyping-by-sequencing-based genome-wide association studies on Verticillium wilt resistance in autotetraploid alfalfa (Medicago sativa L.).

PubMed

Yu, Long-Xi; Zheng, Ping; Zhang, Tiejun; Rodringuez, Jonas; Main, Dorrie

2017-02-01

Verticillium wilt (VW) is a fungal disease that causes severe yield losses in alfalfa. The most effective method to control the disease is through the development and use of resistant varieties. The identification of marker loci linked to VW resistance can facilitate breeding for disease-resistant alfalfa. In the present investigation, we applied an integrated framework of genome-wide association with genotyping-by-sequencing (GBS) to identify VW resistance loci in a panel of elite alfalfa breeding lines. Phenotyping was performed by manual inoculation of the pathogen to healthy seedlings, and scoring for disease resistance was carried out according to the standard test of the North America Alfalfa Improvement Conference (NAAIC). Marker-trait association by linkage disequilibrium identified 10 single nucleotide polymorphism (SNP) markers significantly associated with VW resistance. Alignment of the SNP marker sequences to the M. truncatula genome revealed multiple quantitative trait loci (QTLs). Three, two, one and five markers were located on chromosomes 5, 6, 7 and 8, respectively. Resistance loci found on chromosomes 7 and 8 in the present study co-localized with the QTLs reported previously. A pairwise alignment (blastn) using the flanking sequences of the resistance loci against the M. truncatula genome identified potential candidate genes with putative disease resistance function. With further investigation, these markers may be implemented into breeding programmes using marker-assisted selection, ultimately leading to improved VW resistance in alfalfa. PUBLISHED 2016. THIS ARTICLE IS A U.S. GOVERNMENT WORK AND IS IN THE PUBLIC DOMAIN IN THE USA.

Effects of dairy slurry on silage fermentation characteristics and nutritive value of alfalfa.

PubMed

Coblentz, W K; Muck, R E; Borchardt, M A; Spencer, S K; Jokela, W E; Bertram, M G; Coffey, K P

2014-11-01

Dairy producers frequently ask questions about the risks associated with applying dairy slurry to growing alfalfa (Medicago sativa L.). Our objectives were to determine the effects of applying dairy slurry on the subsequent nutritive value and fermentation characteristics of alfalfa balage. Dairy slurry was applied to 0.17-ha plots of alfalfa; applications were made to the second (HARV1) and third (HARV2) cuttings during June and July of 2012, respectively, at mean rates of 42,400 ± 5271 and 41,700 ± 2397 L/ha, respectively. Application strategies included (1) no slurry, (2) slurry applied directly to stubble immediately after the preceding harvest, (3) slurry applied after 1 wk of post-ensiled regrowth, or (4) slurry applied after 2 wk of regrowth. All harvested forage was packaged in large, rectangular bales that were ensiled as wrapped balage. Yields of DM harvested from HARV1 (2,477 kg/ha) and HARV2 (781 kg/ha) were not affected by slurry application treatment. By May 2013, all silages appeared to be well preserved, with no indication of undesirable odors characteristic of clostridial fermentations. Clostridium tyrobutyricum, which is known to negatively affect cheese production, was not detected in any forage on either a pre- or post-ensiled basis. On a pre-ensiled basis, counts for Clostridium cluster 1 were greater for slurry-applied plots than for those receiving no slurry, and this response was consistent for HARV1 (4.44 vs. 3.29 log10 genomic copies/g) and HARV2 (4.99 vs. 3.88 log10 genomic copies/g). Similar responses were observed on a post-ensiled basis; however, post-ensiled counts also were greater for HARV1 (5.51 vs. 5.17 log10 genomic copies/g) and HARV2 (5.84 vs. 5.28 log10 genomic copies/g) when slurry was applied to regrowth compared with stubble. For HARV2, counts also were greater following a 2-wk application delay compared with a 1-wk delay (6.23 vs. 5.45 log10 genomic copies/g). These results suggest that the risk of clostridial

Co-transforming bar and CsLEA enhanced tolerance to drought and salt stress in transgenic alfalfa (Medicago sativa L.).

PubMed

Zhang, Jiyu; Duan, Zhen; Zhang, Daiyu; Zhang, Jianquan; Di, Hongyan; Wu, Fan; Wang, Yanrong

2016-03-25

Drought and high salinity are two major abiotic factors that restrict alfalfa productivity. A dehydrin protein, CsLEA, from the desert grass Cleistogenes songorica was transformed into alfalfa (Medicago sativa L.) via Agrobacterium-mediated transformation using the bar gene as a selectable marker, and the drought and salt stress tolerances of the transgenic plants were assessed. Thirty-nine of 119 transformants were positive, as screened by Basta, and further molecularly authenticated using PCR and RT-PCR. Phenotype observations revealed that the transgenic plants grew better than the wild-type (WT) plants after 15d of drought stress and 10d of salt stress: the leaves of WT alfalfa turned yellow, whereas the transgenic alfalfa leaves only wilted; after rewatering, the transgenic plants returned to a normal state, though the WT plants could not be restored. Evaluation of physiologic and biochemical indices during drought and salt stresses showed a relatively lower Na(+) content in the leaves of the transgenic plants, which would reduce toxic ion effects. In addition, the transgenic plants were able to maintain a higher relative water content (RWC), higher shoot biomass, fewer photosystem changes, decreased membrane injury, and a lower level of osmotic stress injury. These results demonstrate that overexpression of the CsLEA gene can enhance the drought and salt tolerance of transgenic alfalfa; in addition, carrying the bar gene in the genome may increase herbicide resistance. Copyright © 2016 Elsevier Inc. All rights reserved.

Aphanomyces root rot of alfalfa: widespread distribution of race 2

USDA-ARS?s Scientific Manuscript database

The early spring of 2012 with prolonged wet soil conditions in many parts of the country resulted in reports of poor performance of alfalfa due to Aphanomyces root rot (ARR). Varieties with resistance to ARR are available, although fewer varieties have resistance to both race 1 and race 2 of the pat...

Alfalfa N credits to second-year corn larger than expected

USDA-ARS?s Scientific Manuscript database

Alfalfa can provide substantial amounts of nitrogen (N) to the first crop that follows it. Recent field research on first-year corn confirms that it is highly likely that grain yields will not improve with added fertilizer N, except on very sandy and very clayey soils. It is less clear how much fert...

Milk production response to feeding alfalfa silage inoculated with Lactobacillus plantarum

USDA-ARS?s Scientific Manuscript database

In mini-silo trials, silages treated with a Lactobacillus plantarum silage inoculant (Ecosyl, Yorkshire, UK) had increased in vitro rumen microbial biomass production compared to untreated. Our objective was to determine if alfalfa silage treated with this inoculant could produce a milk production r...

Effects of TT8 and HB12 Silencing on the Relations between the Molecular Structures of Alfalfa ( Medicago sativa) Plants and Their Nutritional Profiles and In Vitro Gas Production.

PubMed

Lei, Yaogeng; Hannoufa, Abdelali; Prates, Luciana Louzada; Shi, Haitao; Wang, Yuxi; Biligetu, Bill; Christensen, David; Yu, Peiqiang

2018-06-06

The objective of this study was to investigate the effects of silencing the TT8 and HB12 genes on the nutritive profiles and in vitro gas production of alfalfa in relation to the spectral molecular structures of alfalfa. TT8-silenced (TT8i, n = 5) and HB12-silenced (HB12i, n = 11) alfalfa were generated by RNA interference (RNAi) and grown with nontransgenic wild type controls (WT, n = 4) in a greenhouse. Alfalfa plants were harvested at early-to-mid vegetative stage. Samples were analyzed for their chemical compositions, CNCPS fractions, and in vitro gas production. Correlations and regressions of the nutritional profiles and in vitro gas production with the molecular spectral structures were also determined. The results showed that the transformed alfalfa had higher digestible fiber and lower crude protein with higher proportions of indigestible protein than WT. HB12 RNAi had lower gas production compared with those of the others. Some chemical, CNCPS, and gas-production profiles were closely correlated with spectral structures and could be well predicted from spectral parameters. In conclusion, the RNAi silencing of TT8 and HB12 in alfalfa altered the chemical, CNCPS and gas-production profiles of alfalfa, and such alterations were closely correlated with the inherent spectral structures of alfalfa.

Genome-Wide association mapping of loci associated with plant growth and forage production under salt stress in alfalfa (Medicago sativa L.)

USDA-ARS?s Scientific Manuscript database

Salinity tolerance is highly desirable to sustain alfalfa production in marginal lands that have been rendered saline. In this study, we used a diverse panel of alfalfa accessions for mapping loci associated with plant growth and forage production under salt stress using genome-wide association stud...

Alfalfa (Medicago sativa L.)/maize (Zea mays L.) intercropping provides a feasible way to improve yield and economic incomes in farming and pastoral areas of northeast China.

PubMed

Sun, Baoru; Peng, Yi; Yang, Hongyu; Li, Zhijian; Gao, Yingzhi; Wang, Chao; Yan, Yuli; Liu, Yanmei

2014-01-01

Given the growing challenges to food and eco-environmental security as well as sustainable development of animal husbandry in the farming and pastoral areas of northeast China, it is crucial to identify advantageous intercropping modes and some constraints limiting its popularization. In order to assess the performance of various intercropping modes of maize and alfalfa, a field experiment was conducted in a completely randomized block design with five treatments: maize monoculture in even rows, maize monoculture in alternating wide and narrow rows, alfalfa monoculture, maize intercropped with one row of alfalfa in wide rows and maize intercropped with two rows of alfalfa in wide rows. Results demonstrate that maize monoculture in alternating wide and narrow rows performed best for light transmission, grain yield and output value, compared to in even rows. When intercropped, maize intercropped with one row of alfalfa in wide rows was identified as the optimal strategy and the largely complementary ecological niches of alfalfa and maize were shown to account for the intercropping advantages, optimizing resource utilization and improving yield and economic incomes. These findings suggest that alfalfa/maize intercropping has obvious advantages over monoculture and is applicable to the farming and pastoral areas of northeast China.

Alfalfa (Medicago sativa L.)/Maize (Zea mays L.) Intercropping Provides a Feasible Way to Improve Yield and Economic Incomes in Farming and Pastoral Areas of Northeast China

PubMed Central

Sun, Baoru; Peng, Yi; Yang, Hongyu; Li, Zhijian; Gao, Yingzhi; Wang, Chao; Yan, Yuli; Liu, Yanmei

2014-01-01

Given the growing challenges to food and eco-environmental security as well as sustainable development of animal husbandry in the farming and pastoral areas of northeast China, it is crucial to identify advantageous intercropping modes and some constraints limiting its popularization. In order to assess the performance of various intercropping modes of maize and alfalfa, a field experiment was conducted in a completely randomized block design with five treatments: maize monoculture in even rows, maize monoculture in alternating wide and narrow rows, alfalfa monoculture, maize intercropped with one row of alfalfa in wide rows and maize intercropped with two rows of alfalfa in wide rows. Results demonstrate that maize monoculture in alternating wide and narrow rows performed best for light transmission, grain yield and output value, compared to in even rows. When intercropped, maize intercropped with one row of alfalfa in wide rows was identified as the optimal strategy and the largely complementary ecological niches of alfalfa and maize were shown to account for the intercropping advantages, optimizing resource utilization and improving yield and economic incomes. These findings suggest that alfalfa/maize intercropping has obvious advantages over monoculture and is applicable to the farming and pastoral areas of northeast China. PMID:25329376

Putrescine Aminopropyltransferase Is Responsible for Biosynthesis of Spermidine, Spermine, and Multiple Uncommon Polyamines in Osmotic Stress-Tolerant Alfalfa.

PubMed Central

Bagga, S.; Rochford, J.; Klaene, Z.; Kuehn, G. D.; Phillips, G. C.

1997-01-01

The biosynthesis of polyamines from the diamine putrescine is not fully understood in higher plants. A putrescine aminopropyltransferase (PAPT) enzyme activity was characterized in alfalfa (Medicago sativa L.). This enzyme activity was highly specific for putrescine as the initial substrate and did not recognize another common diamine, 1,3-diaminopropane, or higher-molecular-weight polyamines such as spermidine and spermine as alternative initial substrates. The enzyme activity was inhibited by a general inhibitor of aminopropyltransferases, 5[prime]-methylthioadenosine, and by a specific inhibitor of PAPTs, cyclohexylammonium sulfate. The initial substrate specificity and inhibition characteristics of the enzyme activity suggested that it is a classical example of a PAPT. However, this enzyme activity yielded multiple polyamine products, which is uncharacteristic of PAPTs. The major reaction product of PAPT activity in alfalfa was spermidine. The next most abundant products of the enzyme reaction using putrescine as the initial substrate included the tetramines spermine and thermospermine. These two tetramines were distinguished by thin-layer chromatography to be distinct reaction products exhibiting differential rates of formation. In addition, the uncommon polyamines homocaldopentamine and homocaldohexamine were tentatively identified as minor enzymatic reaction products but only in extracts prepared from osmotic stresstolerant alfalfa cultivars. PAPT activity from alfalfa was highest in meristematic shoot tip and floral bud tissues and was not detected in older, nonmeristematic tissues. Product inhibition of the enzyme activity was observed after spermidine was added into the in vitro assay for alfalfa PAPT activity. A biosynthetic pathway is proposed that accounts for the characteristics of this PAPT activity and accommodates a novel scheme by which certain uncommon polyamines are produced in plants. PMID:12223719

Microbial inoculation of alfalfa haylage: ensiling characteristics and milk production response when fed to early lactation dairy cows.

PubMed

Kent, B A; Arambel, M J; Winsryg, M D; Walters, J L

1989-09-01

Third-cutting alfalfa hay harvested at bud stage and wilted to approximately 65% moisture was treated with a live bacterial inoculant at the rate of 300,000 cfu/g fresh alfalfa. Treated alfalfa was packed in polyethylene bags. Samples were taken at time of ensiling and d 1, 2, 3, 4, 7, and 28 postensiling. Mean pH was lower in the treated haylage (5.09 and 5.71 for treatment and control, respectively). Mean temperatures were higher in the treated haylage (30.0 and 28.0 degrees C for treatment and control, respectively). Mold count, water-soluble carbohydrate, alpha amino nitrogen, CP, and ADF were not affected by treatment. Regardless of treatment, pH, mold counts, and water-soluble carbohydrates declined with time. There was no significant difference between treatments for DM intake, milk production, and milk composition.

The sky is falling II: Impact of deposition produced during the static testing of solid rocket motors on corn and alfalfa.

PubMed

Doucette, William J; Mendenhall, Scout; McNeill, Laurie S; Heavilin, Justin

2014-06-01

Tests of horizontally restrained rocket motors at the ATK facility in Promontory, Utah, USA result in the deposition of an estimated 1.5million kg of entrained soil and combustion products (mainly aluminum oxide, gaseous hydrogen chloride and water) on the surrounding area. The deposition is referred to as test fire soil (TFS). Farmers observing TFS deposited on their crops expressed concerns regarding the impact of this material. To address these concerns, we exposed corn and alfalfa to TFS collected during a September 2009 test. The impact was evaluated by comparing the growth and tissue composition of controls relative to the treatments. Exposure to TFS, containing elevated levels of chloride (1000 times) and aluminum (2 times) relative to native soils, affected the germination, growth and tissue concentrations of various elements, depending on the type and level of exposure. Germination was inhibited by high concentrations of TFS in soil, but the impact was reduced if the TFS was pre-leached with water. Biomass production was reduced in the TFS amended soils and corn grown in TFS amended soils did not develop kernels. Chloride concentrations in corn and alfalfa grown in TFS amended soils were two orders of magnitude greater than controls. TFS exposed plants contained higher concentrations of several cations, although the concentrations were well below livestock feed recommendations. Foliar applications of TFS had no impact on biomass, but some differences in the elemental composition of leaves relative to controls were observed. Washing the TFS off the leaves lessened the impact. Results indicate that the TFS deposition could have an effect, depending on the amount and growth stage of the crops, but the impact could be mitigated with rainfall or the application of additional irrigation water. The high level of chloride associated with the TFS is the main cause of the observed impacts. Copyright © 2014 Elsevier B.V. All rights reserved.

Inactivation of Escherichia coli O157:H7 and Salmonella by gamma irradiation of alfalfa seed intended for production of food sprouts.

PubMed

Thayer, Donald W; Rajkowski, Kathleen T; Boyd, Glenn; Cooke, Peter H; Soroka, Douglas S

2003-02-01

Inonizing irradiation was determined to be a suitable method for the inactivation of Salmonella and Escherichia coli O157:H7 on alfalfa seed to be used in the production of food sprouts. The radiation D (dose resulting in a 90% reduction of viable CFU) values for the inactivation of Salmonella and E. coli O157:H7 on alfalfa seeds were higher than the D-values for their inactivation on meat or poultry. The average D-value for the inactivation of Salmonella on alfalfa seeds was 0.97 +/- 0.03 kGy; the D-values for cocktails of meat isolates and for vegetable-associated isolates were not significantly different. The D-values for nonoutbreak and outbreak isolates of E. coli O157:H7 on alfalfa seeds were 0.55 +/- 0.01 and 0.60 +/- 0.01 kGy, respectively. It was determined that the relatively high D-values were not due to the low moisture content or the low water activity of the seed. The D-values for Salmonella on alfalfa seeds from two different sources did not differ significantly, even though there were significant differences in seed size and water activity. The increased moisture content of the seed after artificial inoculation did not significantly alter the D-value for the inactivation of Salmonella. The results of this study demonstrate that 3.3- and 2-log inactivations can be achieved with a 2-kGy dose of ionizing radiation, which will permit satisfactory commercial yields of sprouts from alfalfa seed contaminated with E. coli O157:H7 and Salmonella, respectively.

Effects of AN Alfalfa (medicago Sativa) Buffer Strip on Leached δ15NNITRATE Values: Implications for Management of Hydrologic N Losses

NASA Astrophysics Data System (ADS)

Kelley, C. J.; Keller, C. K.; Smith, J. L.; Evans, R. D.; Harlow, B.

2011-12-01

Buffer strips are commonly used to decrease agricultural runoff with the objective of limiting sediment and agrochemicals fluxes to surface waters. The objective of this study was to determine the effects of an alfalfa buffer strip on the magnitude and source(s) of leached nitrate from a dryland agricultural field. Previous research at the Cook Agronomy Farm has inferred two sources of nitrate in tile drain discharge, a high-discharge-season (January through May) synthetic fertilizer source, and a low-discharge-season (June through December) soil organic nitrogen source. This study examines how a change in management strategy and crop species alters the low discharge season nitrate source. In the spring of 2006 an alfalfa buffer strip approximately 20 m wide was planted running approximately north-south in the lowland portion of a 12 ha tile-drained field bordering a ditch that drains into Missouri Flat Creek. Three-year (2003 through 2005) average NO3--N flux prior to the planting of the alfalfa buffer strip was ~0.40 kg ha-1 year-1. After planting, the three-year (2006 through 2008) average NO3--N flux was ~0.38 kg ha-1 year-1. The lack of evident buffer-strip influence on the fluxes may be due in part to the large variation in precipitation amounts and timing that control water flows through the system. Three-year average δ15Nnitrate values for the tile drain pre and post planting of the alfalfa buffer strip were 6.9 ± 1.1 % and 4.2 ± 0.9 % respectively. We hypothesize that the significant difference indicates that the alfalfa strip affects the source of leached nitrate. Before planting the alfalfa buffer strip, the interpreted source of nitrate was mineralization of soil organic nitrogen from non-N2 fixing crops (spring and summer wheat varieties). After planting the alfalfa buffer strip, the source of nitrate was interpreted to be a mixture of mineralized soil organic nitrogen from N2 fixing alfalfa and non-N2 fixing crops. Further work is needed to test

First report of alfalfa (Medicago sativa L.) seed rot, seedling root rot, and damping off caused by Pythium spp. in Sudanese soil

USDA-ARS?s Scientific Manuscript database

Alfalfa is an important forage crop in Sudan but has relatively low biomass yields. In September 2016 soil samples were collected from three commercial alfalfa production fields near Khartoum, Sudan with poor seedling establishment and rapid stand decline. Soil samples from each field were evaluated...

Effects of moisture content or particle size on the in situ degradability of maize silage and alfalfa haylage in lactating dairy cows.

PubMed

Zou, Yang; Dong, Shuangzhao; Du, Yun; Li, Shengli; Wang, Yajing; Cao, Zhijun

2016-09-01

A study using four Holstein cows with ruminal cannulas was conducted to evaluate the degradability of different moisture content or particle size of maize silage and alfalfa haylage. The maize silage (MS; 20-mm length) and alfalfa haylage (AH; 40-mm length) samples were wet (wet maize silage, MSW; wet alfalfa haylage, AHW), dried (dried maize silage, MSD; dried alfalfa haylage, AHD), or ground to pass through a 2.5-mm screen (dried ground maize silage, MSG; dried ground alfalfa haylage, AHG). Samples were incubated in the rumen for 2, 6, 12, 24, 36, 48, and 72 h. Cows were fed ad libitum and allowed free access to water. High moisture content treatment of MSW expressed a lower rinsing NDF and ADF degradability at 2 h ( P  < 0.05) compared with dried samples (MSD and MSG). Different moisture content and particle size had a significant impact ( P  < 0.05) on the NDF degradability at 72 h, ADF degradability at 36, 48, and 72 h, and ruminally degradable ADF. All of the highest values were observed in small particle size and low moisture content AHG treatment. Based on this study, sample processing, such as drying and grinding, should be considered when evaluating nutritive values of forages.

Protein accumulation and rumen stability of wheat γ-gliadin fusion proteins in tobacco and alfalfa.

PubMed

Sun, Xiaodong; Chi-Ham, Cecilia L; Cohen-Davidyan, Tamar; DeBen, Christopher; Getachew, Girma; DePeters, Edward; Putnam, Daniel; Bennett, Alan

2015-09-01

The nutritional value of various crops can be improved by engineering plants to produce high levels of proteins. For example, because methionine deficiency limits the protein quality of Medicago Sativa (alfalfa) forage, producing alfalfa plants that accumulate high levels of a methionine-rich protein could increase the nutritional value of that crop. We used three strategies in designing methionine-rich recombinant proteins that could accumulate to high levels in plants and thereby serve as candidates for improving the protein quality of alfalfa forage. In tobacco, two fusion proteins, γ-gliadin-δ-zein and γ-δ-zein, as well as δ-zein co-expressed with β-zein, all formed protein bodies. However, the γ-gliadin-δ-zein fusion protein accumulated to the highest level, representing up to 1.5% of total soluble protein (TSP) in one transformant. In alfalfa, γ-gliadin-δ-zein accumulated to 0.2% of TSP, and in an in vitro rumen digestion assay, γ-gliadin-δ-zein was more resistant to microbial degradation than Rubisco. Additionally, although it did not form protein bodies, a γ-gliadin-GFP fusion protein accumulated to much higher levels, 7% of TSP, than a recombinant protein comprised of an ER localization signal fused to GFP in tobacco. Based on our results, we conclude that γ-gliadin-δ-zein is a potential candidate protein to use for enhancing methionine levels in plants and for improving rumen stability of forage protein. γ-gliadin fusion proteins may provide a general platform for increasing the accumulation of recombinant proteins in transgenic plants. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

Effects of feeding selenium-enriched alfalfa hay on immunity and health of weaned beef calves.

PubMed

Hall, Jean A; Bobe, Gerd; Vorachek, William R; Hugejiletu; Gorman, M Elena; Mosher, Wayne D; Pirelli, Gene J

2013-12-01

Previously, we reported that feeding selenium (Se)-enriched forage improves antibody titers in mature beef cows, and whole-blood Se concentrations and growth rates in weaned beef calves. Our current objective was to test whether beef calves fed Se-enriched alfalfa hay during the transition period between weaning and movement to a feedlot also have improved immune responses and slaughter weights. Recently weaned beef calves (n = 60) were fed an alfalfa-hay-based diet for 7 weeks, which was harvested from fields fertilized with sodium selenate at 0, 22.5, 45.0, or 89.9 g Se/ha. All calves were immunized with J-5 Escherichia coli bacterin. Serum was collected for antibody titers 2 weeks after the third immunization. Whole-blood neutrophils collected at 6 or 7 weeks were evaluated for total antioxidant potential, bacterial killing activity, and expression of genes associated with selenoproteins and innate immunity. Calves fed the highest versus the lowest level of Se-enriched alfalfa hay had higher antibody titers (P = 0.02), thioredoxin reductase-2 mRNA levels (P = 0.07), and a greater neutrophil total antioxidant potential (P = 0.10), whereas mRNA levels of interleukin-8 receptor (P = 0.02), L-selectin (P = 0.07), and thioredoxin reductase-1 (P = 0.07) were lower. In the feedlot, calves previously fed the highest-Se forage had lower mortality (P = 0.04) and greater slaughter weights (P = 0.02). Our results suggest that, in areas with low-forage Se concentrations, feeding beef calves Se-enriched alfalfa hay during the weaning transition period improves vaccination responses and subsequent growth and survival in the feedlot.

Correlations between environmental factors and wild bee behavior on alfalfa (Medicago sativa) in northwestern China.

PubMed

Wang, Xiaojuan; Liu, Hongping; Li, Xiaoxia; Song, Yu; Chen, Li; Jin, Liang

2009-10-01

To discover the effect of environmental factors on pollinator visitation to flowering Medicago sativa, several field experiments were designed to examine the diurnal movement patterns of wild bee species in the Hexi Corridor of northwestern China. Our study results showed that Megachile abluta, M. spissula, and Xylocopa valga showed unimodal diurnal foraging behavior, whereas Andrena parvula and Anthophora melanognatha showed bimodal diurnal foraging behavior. Correlation analysis indicated that diurnal foraging activities of pollinators were significantly correlated with environmental factors. Correlations of foraging activities versus environmental factors for M. abluta, M. spissula, and X. valga best fit a linear model, whereas those of A. parvula and A. melanognatha best fit a parallel quadratic model. Results of this study indicated that solitary wild bees such as M. abluta, M. spissula, X. valga, A. parvula, and A. melanognatha are potential alfalfa pollinators in the Hexi Corridor. An understanding of the environmental factors that affect the behaviors of different wild bees foraging in alfalfa are basic to the utilization of solitary wild bees in a practical way for increased, or more consistent, pollination of alfalfa for seed production.

Effect of an ozone injury-retardant chemical on isozyme profiles from alfalfa callus in vitro

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rier, J.P.; Sood, V.K.; Whitaker, A.

1983-01-01

Plant ozone injury retardant (EDU or ethylenediurea) at 1.0 ppm inhibited growth of callus of alfalfa cultivars Williamsburg (ozone-sensitive) and MSB-CW5An2(ozone-insensitive) germplasm of Medicago sative. The presence of EDU(0.1 ppm) in growth medium increased the number of protein and peroxidase isozyme bands in alfalfa cultivar stem callus and ozone modified their intensities. Protein profiles of MSB stem callus from media containing EDU or exposed to ozone were unchanged. Marked differences were observed between the peroxidase profiles of ozonated and control ozone-insensitive stem callus from media containing EDU. Protein profiles of ozonated ozone-insensitive leaf callus differed slightly from controls.

Sub-lethal effects of neonicitinoids on the alfalfa leafcutter bee, Megachile rotundata

USDA-ARS?s Scientific Manuscript database

Neonicotinoids are commonly used pesticides in U.S. agriculture. For many beneficial insect species, lethal effects of neonicotinoids are well-documented; however, much less is known about sublethal exposure. The alfalfa leaf cutter bee Megachile rotundata is a managed pollinator that constructs com...

Estimation of the genetic diversity in tetraploid alfalfa populations based on RAPD markers for breeding purposes.

PubMed

Nagl, Nevena; Taski-Ajdukovic, Ksenija; Barac, Goran; Baburski, Aleksandar; Seccareccia, Ivana; Milic, Dragan; Katic, Slobodan

2011-01-01

Alfalfa is an autotetraploid, allogamous and heterozygous forage legume, whose varieties are synthetic populations. Due to the complex nature of the species, information about genetic diversity of germplasm used in any alfalfa breeding program is most beneficial. The genetic diversity of five alfalfa varieties, involved in progeny tests at Institute of Field and Vegetable Crops, was characterized based on RAPD markers. A total of 60 primers were screened, out of which 17 were selected for the analysis of genetic diversity. A total of 156 polymorphic bands were generated, with 10.6 bands per primer. Number and percentage of polymorphic loci, effective number of alleles, expected heterozygosity and Shannon's information index were used to estimate genetic variation. Variety Zuzana had the highest values for all tested parameters, exhibiting the highest level of variation, whereas variety RSI 20 exhibited the lowest. Analysis of molecular variance (AMOVA) showed that 88.39% of the total genetic variation was attributed to intra-varietal variance. The cluster analysis for individual samples and varieties revealed differences in their population structures: variety Zuzana showed a very high level of genetic variation, Banat and Ghareh were divided in subpopulations, while Pecy and RSI 20 were relatively uniform. Ways of exploiting the investigated germplasm in the breeding programs are suggested in this paper, depending on their population structure and diversity. The RAPD analysis shows potential to be applied in analysis of parental populations in semi-hybrid alfalfa breeding program in both, development of new homogenous germplasm, and identification of promising, complementary germplasm.

Enhancement of growth performance in pre-weaning suckling Boer kids supplemented with creep feed containing alfalfa.

PubMed

Htoo, Nay Nang; Khaing, Aung Tun; Abba, Yusuf; Htin, Nwe Nwe; Abdullah, Jesse Faez Firdaus; Kyaw, Than; Khan, Mohd Azam Khan Goriman; Lila, Mohd Azmi Mohd

2015-06-01

This study examined the effects of creep feed (CF) supplementation (with or without Alfalfa) on the pre-weaning growth performance of nursing goat kids. A total of forty eight (48), 7 days old, single born kids (live weight 4.4±0.09 kg) were divided into three treatment groups, each containing eight males and eight females. All three groups had access to their dams' milk (DM). The kids from the first treatment group had free access to CF containing alfalfa (CFA) while those from the second group had free access to CF without alfalfa. The third treatment group (control) had access to their DM only. All three groups were kept isolated from the dams from 800 to 1200 h and from 1400 to 1800 h while having access to CF. Total weight gain and average daily gain of kids from CFA group (11.2±0.36 kg, 145.2±4.64 g) was significantly higher (p<0.05) than kids from CF (7.9±0.49 kg, 102.9±6.43 g) and DM (5.5±0.43 kg, 71.1±5.56 g) groups. The weaning weight of kids from CFA group (15.6±0.39 kg) was significantly higher (p<0.05) than those from CF (12.1±0.56 kg) and DM (9.9±0.59 kg) groups. This result shows that supplementation of CF combined with alfalfa from birth to weaning enhances growth performance of cross-bred Boer goat kids.

Enhancement of growth performance in pre-weaning suckling Boer kids supplemented with creep feed containing alfalfa

PubMed Central

Htoo, Nay Nang; Khaing, Aung Tun; Abba, Yusuf; Htin, Nwe Nwe; Abdullah, Jesse Faez Firdaus; Kyaw, Than; Khan, Mohd Azam Khan Goriman; Lila, Mohd Azmi Mohd

2015-01-01

Aim: This study examined the effects of creep feed (CF) supplementation (with or without Alfalfa) on the pre-weaning growth performance of nursing goat kids. Materials and Methods: A total of forty eight (48), 7 days old, single born kids (live weight 4.4±0.09 kg) were divided into three treatment groups, each containing eight males and eight females. All three groups had access to their dams’ milk (DM). The kids from the first treatment group had free access to CF containing alfalfa (CFA) while those from the second group had free access to CF without alfalfa. The third treatment group (control) had access to their DM only. All three groups were kept isolated from the dams from 800 to 1200 h and from 1400 to 1800 h while having access to CF. Results: Total weight gain and average daily gain of kids from CFA group (11.2±0.36 kg, 145.2±4.64 g) was significantly higher (p<0.05) than kids from CF (7.9±0.49 kg, 102.9±6.43 g) and DM (5.5±0.43 kg, 71.1±5.56 g) groups. The weaning weight of kids from CFA group (15.6±0.39 kg) was significantly higher (p<0.05) than those from CF (12.1±0.56 kg) and DM (9.9±0.59 kg) groups. Conclusion: This result shows that supplementation of CF combined with alfalfa from birth to weaning enhances growth performance of cross-bred Boer goat kids. PMID:27065636

Genome-Wide Association Study Identifies Loci for Salt Tolerance during Germination in Autotetraploid Alfalfa (Medicago sativa L.) Using Genotyping-by-Sequencing

PubMed Central

Yu, Long-Xi; Liu, Xinchun; Boge, William; Liu, Xiang-Ping

2016-01-01

Salinity is one of major abiotic stresses limiting alfalfa (Medicago sativa L.) production in the arid and semi-arid regions in US and other counties. In this study, we used a diverse panel of alfalfa accessions previously described by Zhang et al. (2015) to identify molecular markers associated with salt tolerance during germination using genome-wide association study (GWAS) and genotyping-by-sequencing (GBS). Phenotyping was done by germinating alfalfa seeds under different levels of salt stress. Phenotypic data of adjusted germination rates and SNP markers generated by GBS were used for marker-trait association. Thirty six markers were significantly associated with salt tolerance in at least one level of salt treatments. Alignment of sequence tags to the Medicago truncatula genome revealed genetic locations of the markers on all chromosomes except chromosome 3. Most significant markers were found on chromosomes 1, 2, and 4. BLAST search using the flanking sequences of significant markers identified 14 putative candidate genes linked to 23 significant markers. Most of them were repeatedly identified in two or three salt treatments. Several loci identified in the present study had similar genetic locations to the reported QTL associated with salt tolerance in M. truncatula. A locus identified on chromosome 6 by this study overlapped with that by drought in our previous study. To our knowledge, this is the first report on mapping loci associated with salt tolerance during germination in autotetraploid alfalfa. Further investigation on these loci and their linked genes would provide insight into understanding molecular mechanisms by which salt and drought stresses affect alfalfa growth. Functional markers closely linked to the resistance loci would be useful for MAS to improve alfalfa cultivars with enhanced resistance to drought and salt stresses. PMID:27446182

Genome-Wide Association Study Identifies Loci for Salt Tolerance during Germination in Autotetraploid Alfalfa (Medicago sativa L.) Using Genotyping-by-Sequencing.

PubMed

Yu, Long-Xi; Liu, Xinchun; Boge, William; Liu, Xiang-Ping

2016-01-01

Salinity is one of major abiotic stresses limiting alfalfa (Medicago sativa L.) production in the arid and semi-arid regions in US and other counties. In this study, we used a diverse panel of alfalfa accessions previously described by Zhang et al. (2015) to identify molecular markers associated with salt tolerance during germination using genome-wide association study (GWAS) and genotyping-by-sequencing (GBS). Phenotyping was done by germinating alfalfa seeds under different levels of salt stress. Phenotypic data of adjusted germination rates and SNP markers generated by GBS were used for marker-trait association. Thirty six markers were significantly associated with salt tolerance in at least one level of salt treatments. Alignment of sequence tags to the Medicago truncatula genome revealed genetic locations of the markers on all chromosomes except chromosome 3. Most significant markers were found on chromosomes 1, 2, and 4. BLAST search using the flanking sequences of significant markers identified 14 putative candidate genes linked to 23 significant markers. Most of them were repeatedly identified in two or three salt treatments. Several loci identified in the present study had similar genetic locations to the reported QTL associated with salt tolerance in M. truncatula. A locus identified on chromosome 6 by this study overlapped with that by drought in our previous study. To our knowledge, this is the first report on mapping loci associated with salt tolerance during germination in autotetraploid alfalfa. Further investigation on these loci and their linked genes would provide insight into understanding molecular mechanisms by which salt and drought stresses affect alfalfa growth. Functional markers closely linked to the resistance loci would be useful for MAS to improve alfalfa cultivars with enhanced resistance to drought and salt stresses.

Selection of alfalfa genotypes for resistance to the foliar pathogen Curvularia geniculata.

PubMed

Ávila, Mariana R; Dall'agnol, Miguel; Martinelli, José A; Silva, Gerarda B P DA; Bremm, Carolina; Nunes, Tamyris

2017-01-01

Foliar diseases impose severe restrictions on the persistence and productivity of Medicago sativa, both of which may be increased by developing disease resistant and more competitive genotypes that can improve pasture quality. We found Curvularia geniculata as the principal alfalfa foliar pathogen in the Brazilian state of Rio Grande do Sul (RS). Growth chamber experiments evaluated the resistance of alfalfa genotypes 'E1C4', 'CPPSul', 'ABT 805' and 'CUF-101' to C. geniculata as compared the control 'Crioula' genotype. These genotypes were also evaluated in field trials at a sea level site in Eldorado do Sul in central RS and at two sites £200 m above sea level, one in Bagé municipality in south west RS and the other at a farm near the town of Alto Feliz in north east RS. Plants were spray-inoculated with 1.6 x 106 ml-1 of C. geniculata spores and visually evaluated for leaf damage 14 days later. The C. geniculata infection rates varied from zero to 100%. Alfalfa persistence and forage mean dry mass (DM) production at the Eldorado site were measured during different seasons from November 2013 to January 2015 by calculating the incidence of invasive plants and morphologically separating leaves from stems and calculating both leaf and stem DM. Data were analysed using mixed statistical models. The best results for persistence and forage DM were shown by the 'CPPSul' genotypes (DM = 16,600 kg ha-1) and 'Crioula' (DM = 15,750 kg ha-1). These two genotypes will be used for subsequent investigations and selection cycles.

Evaluation of alfalfa (Medicago sativa L.) populations' response to salinity stress

USDA-ARS?s Scientific Manuscript database

Alfalfa is a moderately salt tolerant crop with high economic return, therefore more suitable for production with lower quality water than most high value crops. This study was conducted to examine the effects of the irrigation water salt type (ST=Cl- or SO4 2-) and five salinity levels (ECiw= 0.85,...

Effects of three-dimensional and color patterns on nest location and progeny mortality in alfalfa leafcutting bee (Hymenoptera: Megachilidae).

PubMed

Guédot, Christelle; Bosch, Jordi; James, Rosalind R; Kemp, William P

2006-06-01

ABSTRACT In alfalfa, Medicago sativa L., seed production where high bee densities are released, alfalfa leafcutting bee, Megachile rotundata (F.) (Hymenoptera: Megachilidae), females may enter several nesting holes before locating their nests. Such levels of "wrong hole" visits lead to an increase in the time spent by females locating their own nests, thereby decreasing alfalfa pollination efficiency and possibly healthy brood production. The objectives of this study were to determine the effect of different nesting board configurations in commercial alfalfa leafcutting bee shelters (separating nesting boards, applying a three-dimensional pattern to the boards, applying a color contrast pattern, or applying a combination of three-dimensional and color contrast patterns) on nest location performance, on the incidence of chalkbrood disease, and on the incidence of broodless provisions. Separating the nesting boards inside shelters improved the ability of females to locate their nests. An increase in nest location performance also occurred in boards with the three-dimensional pattern and the combined three-dimensional and color contrast pattern, compared with the uniform board (a standard configuration currently used commercially). The percentage of provisioned cells that were broodless was not statistically different between treatments, but the percentage of larvae infected with chalkbrood decreased by half in the three-dimensional board design, compared with the uniform board.

Evaluating Headline fungicide on alfalfa production and sensitivity of pathogens to pyraclostrobin

USDA-ARS?s Scientific Manuscript database

Headline fungicide was recently registered for management of foliar diseases on alfalfa. The effect of disease control on yield, forage quality, and potential return on investment for fungicide application was determined for field experiments conducted at five locations in 2012, three in Wisconsin a...

Enhancing forage yields and soil conservation by interseeding alfalfa into silage corn

USDA-ARS?s Scientific Manuscript database

Recent field studies have identified prohexadione-calcium (PHD) as an effective plant growth regulator for enhancing the establishment of alfalfa interseeded into corn as a dual-purpose cover and forage crop. Foliar applications of PHD on seedlings doubled or tripled stand survival of interseeded al...

Reducing water inputs with subsurface drip irrigation may improve alfalfa nutritive value

USDA-ARS?s Scientific Manuscript database

Irrigated alfalfa (Medicago sativa L.) is an important forage crop for western Kansas dairy producers. Concerns over decreasing groundwater supplies have prompted the need to develop more efficient methods of irrigation. We investigated the effects of a subsurface drip irrigation system at three lev...

A Saturated Genetic Linkage Map of Autotetraploid Alfalfa (Medicago sativa L.) Developed Using Genotyping-by-Sequencing Is Highly Syntenous with the Medicago truncatula Genome

PubMed Central

Li, Xuehui; Wei, Yanling; Acharya, Ananta; Jiang, Qingzhen; Kang, Junmei; Brummer, E. Charles

2014-01-01

A genetic linkage map is a valuable tool for quantitative trait locus mapping, map-based gene cloning, comparative mapping, and whole-genome assembly. Alfalfa, one of the most important forage crops in the world, is autotetraploid, allogamous, and highly heterozygous, characteristics that have impeded the construction of a high-density linkage map using traditional genetic marker systems. Using genotyping-by-sequencing (GBS), we constructed low-cost, reasonably high-density linkage maps for both maternal and paternal parental genomes of an autotetraploid alfalfa F1 population. The resulting maps contain 3591 single-nucleotide polymorphism markers on 64 linkage groups across both parents, with an average density of one marker per 1.5 and 1.0 cM for the maternal and paternal haplotype maps, respectively. Chromosome assignments were made based on homology of markers to the M. truncatula genome. Four linkage groups representing the four haplotypes of each alfalfa chromosome were assigned to each of the eight Medicago chromosomes in both the maternal and paternal parents. The alfalfa linkage groups were highly syntenous with M. truncatula, and clearly identified the known translocation between Chromosomes 4 and 8. In addition, a small inversion on Chromosome 1 was identified between M. truncatula and M. sativa. GBS enabled us to develop a saturated linkage map for alfalfa that greatly improved genome coverage relative to previous maps and that will facilitate investigation of genome structure. GBS could be used in breeding populations to accelerate molecular breeding in alfalfa. PMID:25147192

Sludge Biochar Amendment and Alfalfa Revegetation Improve Soil Physicochemical Properties and Increase Diversity of Soil Microbes in Soils from a Rare Earth Element Mining Wasteland

PubMed Central

Inubushi, Kazuyuki; Liang, Jian; Zhu, Sipin; Wei, Zhenya; Guo, Xiaobin; Luo, Xianping

2018-01-01

Long-term unregulated mining of ion-adsorption clays (IAC) in China has resulted in severe ecological destruction and created large areas of wasteland in dire need of rehabilitation. Soil amendment and revegetation are two important means of rehabilitation of IAC mining wasteland. In this study, we used sludge biochar prepared by pyrolysis of municipal sewage sludge as a soil ameliorant, selected alfalfa as a revegetation plant, and conducted pot trials in a climate-controlled chamber. We investigated the effects of alfalfa revegetation, sludge biochar amendment, and their combined amendment on soil physicochemical properties in soil from an IAC mining wasteland as well as the impact of sludge biochar on plant growth. At the same time, we also assessed the impacts of these amendments on the soil microbial community by means of the Illumina Miseq sequences method. Results showed that alfalfa revegetation and sludge biochar both improved soil physicochemical properties and microbial community structure. When alfalfa revegetation and sludge biochar amendment were combined, we detected additive effects on the improvement of soil physicochemical properties as well as increases in the richness and diversity of bacterial and fungal communities. Redundancy analyses suggested that alfalfa revegetation and sludge biochar amendment significantly affected soil microbial community structure. Critical environmental factors consisted of soil available K, pH, organic matter, carbon–nitrogen ratio, bulk density, and total porosity. Sludge biochar amendment significantly promoted the growth of alfalfa and changed its root morphology. Combining alfalfa the revegetation with sludge biochar amendment may serve to not only achieve the revegetation of IAC mining wasteland, but also address the challenge of municipal sludge disposal by making the waste profitable. PMID:29751652

Sludge Biochar Amendment and Alfalfa Revegetation Improve Soil Physicochemical Properties and Increase Diversity of Soil Microbes in Soils from a Rare Earth Element Mining Wasteland.

PubMed

Luo, Caigui; Deng, Yangwu; Inubushi, Kazuyuki; Liang, Jian; Zhu, Sipin; Wei, Zhenya; Guo, Xiaobin; Luo, Xianping

2018-05-11

Long-term unregulated mining of ion-adsorption clays (IAC) in China has resulted in severe ecological destruction and created large areas of wasteland in dire need of rehabilitation. Soil amendment and revegetation are two important means of rehabilitation of IAC mining wasteland. In this study, we used sludge biochar prepared by pyrolysis of municipal sewage sludge as a soil ameliorant, selected alfalfa as a revegetation plant, and conducted pot trials in a climate-controlled chamber. We investigated the effects of alfalfa revegetation, sludge biochar amendment, and their combined amendment on soil physicochemical properties in soil from an IAC mining wasteland as well as the impact of sludge biochar on plant growth. At the same time, we also assessed the impacts of these amendments on the soil microbial community by means of the Illumina Miseq sequences method. Results showed that alfalfa revegetation and sludge biochar both improved soil physicochemical properties and microbial community structure. When alfalfa revegetation and sludge biochar amendment were combined, we detected additive effects on the improvement of soil physicochemical properties as well as increases in the richness and diversity of bacterial and fungal communities. Redundancy analyses suggested that alfalfa revegetation and sludge biochar amendment significantly affected soil microbial community structure. Critical environmental factors consisted of soil available K, pH, organic matter, carbon⁻nitrogen ratio, bulk density, and total porosity. Sludge biochar amendment significantly promoted the growth of alfalfa and changed its root morphology. Combining alfalfa the revegetation with sludge biochar amendment may serve to not only achieve the revegetation of IAC mining wasteland, but also address the challenge of municipal sludge disposal by making the waste profitable.

Citric acid- and Tween(®) 80-assisted phytoremediation of a co-contaminated soil: alfalfa (Medicago sativa L.) performance and remediation potential.

PubMed

Agnello, A C; Huguenot, D; van Hullebusch, E D; Esposito, G

2016-05-01

A pot experiment was designed to assess the phytoremediation potential of alfalfa (Medicago sativa L.) in a co-contaminated (i.e., heavy metals and petroleum hydrocarbons) soil and the influence of citric acid and Tween(®) 80 (polyethylene glycol sorbitan monooleate), applied individually and combined together, for their possible use in chemically assisted phytoremediation. The results showed that alfalfa plants could tolerate and grow in a co-contaminated soil. Over a 90-day experimental time, shoot and root biomass increased and negligible plant mortality occurred. Heavy metals were uptaken by alfalfa to a limited extent, mostly by plant roots, and their concentration in plant tissues were in the following order: Zn > Cu > Pb. Microbial population (alkane-degrading microorganisms) and activity (lipase enzyme) were enhanced in the presence of alfalfa with rhizosphere effects of 9.1 and 1.5, respectively, after 90 days. Soil amendments did not significantly enhance plant metal concentration or total uptake. In contrast, the combination of citric acid and Tween(®) 80 significantly improved alkane-degrading microorganisms (2.4-fold increase) and lipase activity (5.3-fold increase) in the rhizosphere of amended plants, after 30 days of experiment. This evidence supports a favorable response of alfalfa in terms of tolerance to a co-contaminated soil and improvement of rhizosphere microbial number and activity, additionally enhanced by the joint application of citric acid and Tween(®) 80, which could be promising for future phytoremediation applications.

Nitrogen reserves, spring regrowth and winter survival of field-grown alfalfa (Medicago sativa) defoliated in the autumn.

PubMed

Dhont, Catherine; Castonguay, Yves; Nadeau, Paul; Bélanger, Gilles; Drapeau, Raynald; Laberge, Serge; Avice, Jean-Christophe; Chalifour, François-P

2006-01-01

The objective of the study was to characterize variations in proline, arginine, histidine, vegetative storage proteins, and cold-inducible gene expression in overwintering roots of field-grown alfalfa, in response to autumn defoliation, and in relation to spring regrowth and winter survival. Field trials, established in 1996 in eastern Canada, consisted of two alfalfa cultivars ('AC Caribou' and 'WL 225') defoliated in 1997 and 1998 either only twice during the summer or three times with the third defoliation taken 400, 500 or 600 growing degree days (basis 5 degrees C) after the second summer defoliation. The root accumulation of proline, arginine, histidine and soluble proteins of 32, 19 and 15 kDa, characterized as alfalfa vegetative storage proteins, was reduced the following spring by an early autumn defoliation at 400 or 500 growing degree days in both cultivars; the 600-growing-degree-days defoliation treatment had less or no effect. Transcript levels of the cold-inducible gene msaCIA, encoding a glycine-rich protein, were markedly reduced by autumn defoliation in 'WL 225', but remained unaffected in the more winter-hardy cultivar 'AC Caribou'. The expression of another cold-inducible gene, the dehydrin homologue msaCIG, was not consistently affected by autumn defoliation. Principal component analyses, including components of root organic reserves at the onset of winter, along with yield and plant density in the following spring, revealed that (a) amino acids and soluble proteins are positively related to the vigour of spring regrowth but poorly related to winter survival and (b) winter survival, as indicated by plant density in the spring, is associated with higher concentrations of cryoprotective sugars in alfalfa roots the previous autumn. An untimely autumn defoliation of alfalfa reduces root accumulation of specific N reserves such as proline, arginine, histidine and vegetative storage proteins that are positively related to the vigour of spring

Effects of feeding pregnant beef cows selenium-enriched alfalfa hay on selenium status and antibody titers in their newborn calves.

PubMed

Wallace, L G; Bobe, G; Vorachek, W R; Dolan, B P; Estill, C T; Pirelli, G J; Hall, J A

2017-06-01

In newborn dairy calves, it has been demonstrated that supranutritional maternal and colostral Se supplementation using Se yeast or sodium selenite, respectively, improves passive transfer of IgG. In beef cattle, agronomic biofortification with Se is a more practical alternative for Se supplementation, whereby the Se concentration of hay is increased through the use of Se-containing fertilizer amendments. It has been previously demonstrated that agronomic Se biofortification is an effective strategy to improve immunity and performance in Se-replete weaned beef calves. The objective of this experiment was to determine the effects of feeding beef cows Se-enriched alfalfa () hay during the last 8 to 12 wk of gestation on passive transfer of antibodies to calves. At 10 wk ± 16 d before calving, 45 cows were assigned to 1 of 3 treatment groups with 3 pens (5 cows/pen) per treatment: Control cows were fed non-Se-fortified alfalfa hay plus a mineral supplement containing 120 mg/kg Se from sodium selenite, Med-Se cows were fed alfalfa hay fertilized with 45.0 g Se/ha as sodium selenate, and High-Se cows were fed alfalfa hay fertilized with 89.9 g Se/ha as sodium selenate; both the Med-Se and the High-Se groups received mineral supplement without added Se. Colostrum and whole blood (WB) were collected from cows at calving, and WB was collected from calves within 2 h of calving and at 12, 24, 36, and 48 h of age. Concentrations of IgG1 and J-5 antibody in cow colostrum and calf serum were quantified using ELISA procedures. Selenium concentrations linearly increased in WB ( < 0.001) and colostrum ( < 0.001) of cows and in WB of newborn calves ( < 0.001) with increasing Se concentration in alfalfa hay. Colostrum concentrations of IgG1 ( = 0.03) were increased in cows fed Se-biofortified alfalfa hay, but J-5 antibody ( = 0.43) concentrations were not. Calf serum IgG1 ( = 0.43) and J-5 antibody ( = 0.44) concentrations during the first 48 h of age were not affected by prior Se

Phytoremediation of polycyclic aromatic hydrocarbons (PAH) by cv. Crioula: A Brazilian alfalfa cultivar.

PubMed

Alves, Wilber S; Manoel, Evelin A; Santos, Noemi S; Nunes, Rosane O; Domiciano, Giselli C; Soares, Marcia R

2018-07-03

This work aimed to evaluate the phytoremediation capacity of the alfalfa cultivar Crioula in soils contaminated with polycyclic aromatic hydrocarbons (PAHs), primary pollutants with mutagenic and carcinogenic potential. Alfalfa was grown from seed for 40 days on soil amended with anthracene, pyrene, and phenanthrene. Soil and plant tissue was collected for biometric assay, dry mass analysis, and PAH analysis by liquid chromatography. Increased total PAH concentration was associated with decreases in plant biomass, height, and internode length. The Crioula cultivar had a satisfactory phytoremediation effect, reducing total PAH concentration (300 ppm) in the experimental soil by 85% in 20 days, and by more than 95% in 40 days. The PAH showed a tendency to be removed in the temporal order: phenanthrene before pyrene before anthracene, and the removal ratio was influenced by the initial soil concentration of each PAH.

Soil sulfur amendments suppress Selenium uptake by alfalfa and western wheatgrass

Treesearch

C. L. Mackowiak; M. C. Amacher

2008-01-01

Selenium (Se) is a potential soil contaminant in many parts of the world where it can pose a health risk to livestock and wildlife. Phosphate ore mining in Southeast Idaho has resulted in numerous waste rock dumps revegetated with forages to stabilize the dumps and support grazing. Alfalfa (Medicago sativa L.), smooth brome (Bromus inermis...

Ractopamine uptake by alfalfa (Medicago sativa) and wheat (Triticum aestivum) from soil

USDA-ARS?s Scientific Manuscript database

Ractopamine is a beta adrenergic agonist used as a growth promoter in swine, cattle and turkeys. To test whether ractopamine has the potential to accumulate in plants grown in contaminated soil, a greenhouse study was conducted with alfalfa (Medicago sativa) and wheat (Triticum aestivum) grown in t...

Divergent alfalfa root system architecture is maintained across environment and nutrient supply

USDA-ARS?s Scientific Manuscript database

Plant root system architecture can alter and be altered by soil fertility and other environmental conditions. In soils with suboptimal fertility, plant root length often is correlated with P and K uptake because these nutrients are supplied by diffusion. We developed alfalfa (Medicago sativa L.) pop...

Photosynthesis of alfalfa (Medicago sativa) in response to landfill leachate contamination.

PubMed

Yang, Lie; Sun, Tiantian; Liu, Yanli; Guo, Houqing; Lv, Lixin; Zhang, Jie; Liu, Chang

2017-11-01

Thousands of unlined landfills and open dumpsites have put great threat on the security of soil and ground water due to leachate leakage. Alfalfa is believed potential as a phytoremediation plant for leachate contamination based on strong root system and the excellent capacity of removing various kinds of pollutants. A lab-scale investigation was conducted to figure out the sensitiveness of alfalfa photosynthesis in response to leachate contamination. The results demonstrated that both of the maximum photosynthetic efficiency (F v /F m ) and net photosynthetic rate (P n ) were slightly inhibited in the high-dosage group. Based on statistical analysis, higher sensitivity of P n to leaching parameters than F v /F m was observed. There were significant correlations between most of leaching parameters (pH, ammonium and COD) and P n with correlation coefficients of 0.530, -0.580 and -0.578 (p < 0.01), respectively. Therefore, P n is potential for acting as an effective indicator for staple leaching characteristics of leachate contaminated soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

Characterization and comparison of the temporal dynamics of ruminal bacterial microbiota colonizing rice straw and alfalfa hay within ruminants.

PubMed

Liu, Junhua; Zhang, Mengling; Xue, Chunxu; Zhu, Weiyun; Mao, Shengyong

2016-12-01

Three ruminally cannulated Holstein cows were used to characterize the dynamics of bacterial colonization of rice straw and alfalfa hay and to assess the differences in the composition and inferred gene function of the colonized microbiota between these 2 forages. Nonincubated (0h) rice straw and alfalfa hay samples and residues in nylon bags incubated for 0.5, 2, 6, 16, and 48h were analyzed for dry matter and were used for DNA extraction and MiSeq (Illumina Inc., San Diego, CA) sequencing of the 16S rRNA gene. The microbial communities that colonized the air-dried and nonincubated (0h) rice straw and alfalfa hay were both dominated by members of the Proteobacteria (contributing toward 70.47% of the 16S RNA reads generated). In situ incubation of the 2 forages revealed major shifts in the community composition: Proteobacteria were replaced within 30min by members belonging to the Bacteroidetes and Firmicutes, contributing toward 51.9 and 36.6% of the 16S rRNA reads generated, respectively. A second significant shift was observed after 6h of rumen incubation, when members of the Spirochaetes and Fibrobacteria phyla became abundant in the forage-adherent community. During the first 30min of rumen incubation, ~20.7 and 36.1% of the rice straw and alfalfa hay, respectively, were degraded, whereas little biomass degradation occurred between 30min and 2h after the rice straw or alfalfa hay was placed in the rumen. Significant differences were noted in attached bacterial community structure between the 2 forage groups, and the abundances of dominant genera Anaeroplasma, Butyrivibrio, Fibrobacter, and Prevotella were affected by the forage types. Real-time PCR results showed that the 16S rRNA copies of total bacteria attached to these 2 forages were affected by the forage types and incubation time, and higher numbers of attached bacterial 16S rRNA were observed in the alfalfa hay samples than in the rice straw from 0.5 to 16h of incubation. The metagenomes predicted by

Grain-based versus alfalfa-based subacute ruminal acidosis induction experiments: Similarities and differences between changes in milk fatty acids.

PubMed

Colman, E; Khafipour, E; Vlaeminck, B; De Baets, B; Plaizier, J C; Fievez, V

2013-07-01

Subacute ruminal acidosis (SARA) is one of the most important metabolic disorders, traditionally characterized by low rumen pH, which might be induced by an increase in the dietary proportion of grains as well as by a reduction of structural fiber. Both approaches were used in earlier published experiments in which SARA was induced by replacing part of the ration by a grain mixture or alfalfa hay by alfalfa pellets. The main differences between both experiments were the presence of blood lipopolysaccharide and Escherichia coli and associated effects on the rumen microbial population in the rumen of grain-based induced SARA animals as well as a great amount of quickly fermentable carbohydrates in the grain-based SARA induction experiment. Both induction approaches changed rumen pH although the pH decrease was more substantial in the alfalfa-based SARA induction protocol. The goal of the current analysis was to assess whether both acidosis induction approaches provoked similar shifts in the milk fatty acid (FA) profile. Similar changes of the odd- and branched-chain FA and the C18 biohydrogenation intermediates were observed in the alfalfa-based SARA induction experiment and the grain-based SARA induction experiment, although they were more pronounced in the former. The proportion of trans-10 C18:1 in the last week of the alfalfa-based induction experiment was 6 times higher than the proportion measured during the control week. The main difference between both induction experiments under similar rumen pH changes was the decreasing sum of iso FA during the grain-based SARA induction experiment whereas the sum of iso FA remained stable during the alfalfa-based SARA induction experiment. The cellulolytic bacterial community seemed to be negatively affected by either the presence of E. coli and the associated lipopolysaccharide accumulation in the rumen or by the amount of starch and quickly fermentable carbohydrates in the diet. In general, changes in the milk FA

Pythium and Fusarium species causing seed rot and damping-off of alfalfa

USDA-ARS?s Scientific Manuscript database

Seed rot and damping-off is an important disease of alfalfa, severely affecting stand establishment when conditions favor the disease. This disease may have been overlooked as a cause of poor stand establishment and reduced vigor of adult plants. Globally, 15 Pythium species have been found to cause...

Effect of treating alfalfa silage with pistachio by-products extract on Saanen dairy goats performance and microbial nitrogen synthesis.

PubMed

Mokhtarpour, A; Naserian, A A; Pourmollae, F; Ghaffari, M H

2016-08-01

A lactation experiment was conducted to determine the influence of addition of pistachio by-products extract (PBE) to alfalfa silage (AS) on performance, rumen fermentation, milk yield and composition, and microbial nitrogen synthesis. Eight multiparous dairy goats (1.8 ± 0.25 kg of milk yield) were used in a replicated 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments to compare two types of AS (supplemented with or without PBE) with two levels of dietary crude protein (14% vs. 16% CP). Dietary treatments were (i) AS with 14% CP of DM diet without PBE (14%CP-PBE), (ii) AS with 14% CP of DM diet with PBE (14%CP + PBE), (iii) AS with 16% CP of DM diet without PBE (16%CP-PBE) and (iv) AS with 16% CP of DM diet with PBE (16%CP + PBE). PBE was sprayed on fresh alfalfa at a ratio of 500 ml/kg alfalfa DM to get the final concentration of 1% tannin as tannic acid equivalent on DM basis. Intake of CP was greater (p < 0.01) in goats fed 16% CP diets than those fed 14% CP diets, regardless of PBE supplementation. Supplementation of PBE tended to decrease (p = 0.09) rumen NH3 -N concentration regardless of the level of CP in the diet. Supplementation of PBE tended (p = 0.09) to decrease total purine derivatives regardless of the level of CP in the diet with no significant change in microbial nitrogen supply. Efficiency of microbial nitrogen synthesis (EMNS) had a tendency (p = 0.07) to decrease in PBE supplemented diets. There was also a tendency (p = 0.10) for more EMNS in 14% CP fed goats than those fed 16% CP diets. Therefore, AS supplemented with PBE may lead to less concentration of ruminal NH3 -N because of decreased degradation of CP by rumen micro-organisms in response to pistachio by-products tannins. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

Identification of Single-Nucleotide Polymorphic Loci Associated with Biomass Yield under Water Deficit in Alfalfa (Medicago sativa L.) Using Genome-Wide Sequencing and Association Mapping

PubMed Central

Yu, Long-Xi

2017-01-01

Alfalfa is a worldwide grown forage crop and is important due to its high biomass production and nutritional value. However, the production of alfalfa is challenged by adverse environmental factors such as drought and other stresses. Developing drought resistance alfalfa is an important breeding target for enhancing alfalfa productivity in arid and semi-arid regions. In the present study, we used genotyping-by-sequencing and genome-wide association to identify marker loci associated with biomass yield under drought in the field in a panel of diverse germplasm of alfalfa. A total of 28 markers at 22 genetic loci were associated with yield under water deficit, whereas only four markers associated with the same trait under well-watered condition. Comparisons of marker-trait associations between water deficit and well-watered conditions showed non-similarity except one. Most of the markers were identical across harvest periods within the treatment, although different levels of significance were found among the three harvests. The loci associated with biomass yield under water deficit located throughout all chromosomes in the alfalfa genome agreed with previous reports. Our results suggest that biomass yield under drought is a complex quantitative trait with polygenic inheritance and may involve a different mechanism compared to that of non-stress. BLAST searches of the flanking sequences of the associated loci against DNA databases revealed several stress-responsive genes linked to the drought resistance loci, including leucine-rich repeat receptor-like kinase, B3 DNA-binding domain protein, translation initiation factor IF2, and phospholipase-like protein. With further investigation, those markers closely linked to drought resistance can be used for MAS to accelerate the development of new alfalfa cultivars with improved resistance to drought and other abiotic stresses. PMID:28706532

A saturated genetic linkage map of autotetraploid alfalfa (Medicago sativa L.) developed using genotyping-by-sequencing is highly syntenous with the Medicago truncatula genome.

PubMed

Li, Xuehui; Wei, Yanling; Acharya, Ananta; Jiang, Qingzhen; Kang, Junmei; Brummer, E Charles

2014-08-21

A genetic linkage map is a valuable tool for quantitative trait locus mapping, map-based gene cloning, comparative mapping, and whole-genome assembly. Alfalfa, one of the most important forage crops in the world, is autotetraploid, allogamous, and highly heterozygous, characteristics that have impeded the construction of a high-density linkage map using traditional genetic marker systems. Using genotyping-by-sequencing (GBS), we constructed low-cost, reasonably high-density linkage maps for both maternal and paternal parental genomes of an autotetraploid alfalfa F1 population. The resulting maps contain 3591 single-nucleotide polymorphism markers on 64 linkage groups across both parents, with an average density of one marker per 1.5 and 1.0 cM for the maternal and paternal haplotype maps, respectively. Chromosome assignments were made based on homology of markers to the M. truncatula genome. Four linkage groups representing the four haplotypes of each alfalfa chromosome were assigned to each of the eight Medicago chromosomes in both the maternal and paternal parents. The alfalfa linkage groups were highly syntenous with M. truncatula, and clearly identified the known translocation between Chromosomes 4 and 8. In addition, a small inversion on Chromosome 1 was identified between M. truncatula and M. sativa. GBS enabled us to develop a saturated linkage map for alfalfa that greatly improved genome coverage relative to previous maps and that will facilitate investigation of genome structure. GBS could be used in breeding populations to accelerate molecular breeding in alfalfa. Copyright © 2014 Li et al.

Identification of Loci Associated with Drought Resistance Traits in Heterozygous Autotetraploid Alfalfa (Medicago sativa L.) Using Genome-Wide Association Studies with Genotyping by Sequencing.

PubMed

Zhang, Tiejun; Yu, Long-Xi; Zheng, Ping; Li, Yajun; Rivera, Martha; Main, Dorrie; Greene, Stephanie L

2015-01-01

Drought resistance is an important breeding target for enhancing alfalfa productivity in arid and semi-arid regions. Identification of genes involved in drought tolerance will facilitate breeding for improving drought resistance and water use efficiency in alfalfa. Our objective was to use a diversity panel of alfalfa accessions comprised of 198 cultivars and landraces to identify genes involved in drought tolerance. The panel was selected from the USDA-ARS National Plant Germplasm System alfalfa collection and genotyped using genotyping by sequencing. A greenhouse procedure was used for phenotyping two important traits associated with drought tolerance: drought resistance index (DRI) and relative leaf water content (RWC). Marker-trait association identified nineteen and fifteen loci associated with DRI and RWC, respectively. Alignments of target sequences flanking to the resistance loci against the reference genome of M. truncatula revealed multiple chromosomal locations. Markers associated with DRI are located on all chromosomes while markers associated with RWC are located on chromosomes 1, 2, 3, 4, 5, 6 and 7. Co-localizations of significant markers between DRI and RWC were found on chromosomes 3, 5 and 7. Most loci associated with DRI in this work overlap with the reported QTLs associated with biomass under drought in alfalfa. Additional significant markers were targeted to several contigs with unknown chromosomal locations. BLAST search using their flanking sequences revealed homology to several annotated genes with functions in stress tolerance. With further validation, these markers may be used for marker-assisted breeding new alfalfa varieties with drought resistance and enhanced water use efficiency.

A Vesicular Arbuscular Mycorrhizal Fungus (Glomus intraradix) Induces a Defense Response in Alfalfa Roots.

PubMed

Volpin, H.; Elkind, Y.; Okon, Y.; Kapulnik, Y.

1994-02-01

Flavonoid accumulation and activities of phenylalanine ammonia-lyase (PAL), chalcone isomerase (CHI), and chitinase were followed during early colonization of alfalfa roots (Medicago sativa L. cv Gilboa) by vesicular arbuscular (VA) fungi (Glomus intraradix). Formononetin was the only flavonoid detected that showed a consistent increase in the inoculated roots. This increase depended only on the presence of the fungus in the plant rhizosphere; no colonization of the root tissue was required. CHI and chitinase activities increased in inoculated roots prior to colonization, whereas the increase in PAL activity coincided with colonization. After reaching a maximum, activities of all enzymes declined to below those of uninoculated roots. PAL inactivation was not caused by a soluble inhibitor. Our results indicate that VA fungi initiate a host defense response in alfalfa roots, which is subsequently suppressed.

The impact of genotyping-by-sequencing pipelines on SNP discovery and identification of markers associated verticillium wilt resistance in autotetraploid alfalfa (sedicago sativa l.)

USDA-ARS?s Scientific Manuscript database

Verticillium wilt (VW) of alfalfa is a soilborne disease that causes severe yield loss in alfalfa. To identify molecular markers associated with VW resistance, an integrated framework of genome-wide association study (GWAS) with high-throughput genotyping by sequencing (GBS) was used for mapping lo...

Using microcontrollers to study emergence rhythms of the alfalfa leafcutting bee, Megachile rotundata

USDA-ARS?s Scientific Manuscript database

An important aspect of pollination is phenological overlap of natural events, such as peak flower bloom coinciding with pollinator emergence. Pollinator emergence can be impacted by environmental cues that inform their internal clocks. The alfalfa leafcutting bee, Megachile rotundata is a solitary, ...

Characterizing thermal performance of an important pollinator, the alfalfa leafcutting bee Megachile rotundata

USDA-ARS?s Scientific Manuscript database

The alfalfa leafcutting bee, Megachile rotundata, undergoes metamorphosis in the spring when temperatures can be highly variable. It is unknown how cold tolerance varies across metamorphosis. We found earlier stages were more tolerant to cold exposure than later stages. Furthermore, we found exposur...

Alfalfa (Medicago sativa L.) is tolerant to higher levels of salinity than previous guidelines indicated: Implications of field and greenhouse studies

NASA Astrophysics Data System (ADS)

Putnam, Daniel H.; Benes, Sharon; Galdi, Giuliano; Hutmacher, Bob; Grattan, Steve

2017-04-01

Alfalfa (Medicago sativa L.) is the most widely grown leguminous forage crop in North America and is valued for high productivity, quality, economic value, and for dairy productivity. Alfalfa has historically been classified as moderately sensitive to saline conditions, with yield declines predicted at >2 dS/m in the saturated soil paste extract. However, greenhouse, sand tank, and field studies over the past five years have confirmed that alfalfa can be grown with limited negative effects at much higher salinity levels. A broad collection of alfalfa varieties has exhibited a range of resistance at irrigation water salinities >5 dS/m ECw in greenhouse trials, with significant variation due to variety. USDA-ARS sand tank studies indicated similar or greater tolerances closer to 8 dS/m in the soil water, in addition to confirmation of significant varietal differences. A three-year field study on clay loam soil with applications of 5-7 dS/m ECw irrigation water indicated normal yields and excellent stand survivability. A second field study in the same soil type with levels from 8-10 dS/m ECw showed yield reductions of 10-15% but economic yields were still achieved at those levels. Field and greenhouse studies were conducted with mixed salt saline sodic waters typical of the San Joaquin Valley of California. Field evaluation of variety performance was subject to greater variation due to secondary salinity-soil interactions including water infiltration and crusting problems, not only salinity per-se. Thus, adequate irrigation water availability to the crop may be as important as salinity in impacting yields under field conditions. Once established, the deep-rooted characteristics of alfalfa enable utilization of deeper subsurface moisture, even at moderate to high salinity levels, as documented by USDA lysimeter studies. Significant advantages to salinity-tolerant varieties have been observed. It will be important to consider specific management factors which may enable

Dietary Alfalfa and Calcium Salts of Long-Chain Fatty Acids Alter Protein Utilization, Microbial Populations, and Plasma Fatty Acid Profile in Holstein Freemartin Heifers.

PubMed

He, Yang; Qiu, Qinghua; Shao, Taoqi; Niu, Wenjing; Xia, Chuanqi; Wang, Haibo; Li, Qianwen; Gao, Zhibiao; Yu, Zhantao; Su, Huawei; Cao, Binghai

2017-12-20

This study presented the effects of alfalfa and calcium salts of long-chain fatty acids (CSFA) on feed intake, apparent digestibility, rumen fermentation, microbial community, plasma biochemical parameters, and fatty acid profile in Holstein freemartin heifers. Eight Holstein freemartin heifers were randomly divided into a 4 × 4 Latin Square experiment with 2 × 2 factorial diets, with or without alfalfa or CSFA. Dietary supplementation of CSFA significantly increased the apparent digestibility of dry matter, crude protein, neutral detergent fiber, organic matter, and significantly reduced N retention (P < 0.05). CSFA increased the concentration of ammonia nitrogen in the ruminal fluid (P < 0.05), but alfalfa increased the concentration of valerate and isovalerate (P < 0.05). CSFA increased the concentration of ammonia nitrogen and the relative population of Streptococcus bovis in the rumen (P < 0.05) and inhibited the relative population of Ruminococcus flavefaciens, methanogens, and protozoa (P < 0.05). Alfalfa instead of Leymus chinensis increased the relative population of Butyrivibrio fibrisolvens and Ruminobacter amylophilus in the rumen (P < 0.05) and reduced the relative population of the Ruminococcus albus and Megasphaera elsdenii (P < 0.05). Supplemental CSFA increased the concentration of cholesterol and low-density lipoprotein cholesterol in the plasma (P < 0.05). And it also altered the composition of fatty acids in the plasma, which was expressed in reducing saturated fatty acid (ΣSFA) ratio and C14-C17 fatty acids proportion except C16:0 (P < 0.05) and increasing the proportion of polyunsaturated fatty acid (ΣPUFA) and unsaturated fatty acid (ΣUFA) (P < 0.05). The results showed that alfalfa and CSFA had interaction effect on the apparent digestibility of ether extracts, plasma triglyceride concentration, isobutyrate concentration, and Ruminococcus albus relative abundance in the rumen. It was concluded that alfalfa substituting Leymus chinensis

Managing foliar and root rot diseases of alfalfa for improving yield and persistance

USDA-ARS?s Scientific Manuscript database

Resistance to the six most common diseases across the United States is available in modern alfalfa cultivars. However, several diseases are becoming increasing problems in many parts of the country. Recognizing these problems is the first step in using crop management strategies to minimize diseases...

Alfalfa stand length and subsequent crop patterns in the upper Midwestern United States

USDA-ARS?s Scientific Manuscript database

To gain perspective on alfalfa (Medicago sativa L.), annual crop rotations in the upper midwestern United States, USDA-National Agricultural Statistics Service (NASS) cropland data layers (CDLs) and USDA-NRCS soil survey layers were combined for six states (North Dakota, South Dakota, Nebraska, Minn...

Isolation and Characterization of Alfalfa-Nodulating Rhizobia Present in Acidic Soils of Central Argentina and Uruguay

PubMed Central

del Papa, María F.; Balagué, Laura J.; Sowinski, Susana Castro; Wegener, Caren; Segundo, Eduardo; Abarca, Francisco Martínez; Toro, Nicolás; Niehaus, Karsten; Pühler, Alfred; Aguilar, O. Mario; Martínez-Drets, Gloria; Lagares, Antonio

1999-01-01

We describe the isolation and characterization of alfalfa-nodulating rhizobia from acid soils of different locations in Central Argentina and Uruguay. A collection of 465 isolates was assembled, and the rhizobia were characterized for acid tolerance. Growth tests revealed the existence of 15 acid-tolerant (AT) isolates which were able to grow at pH 5.0 and formed nodules in alfalfa with a low rate of nitrogen fixation. Analysis of those isolates, including partial sequencing of the genes encoding 16S rRNA and genomic PCR-fingerprinting with MBOREP1 and BOXC1 primers, demonstrated that the new isolates share a genetic background closely related to that of the previously reported Rhizobium sp. Or191 recovered from an acid soil in Oregon (B. D. Eardly, J. P. Young, and R. K. Selander, Appl. Environ. Microbiol. 58:1809–1815, 1992). Growth curves, melanin production, temperature tolerance, and megaplasmid profiles of the AT isolates were all coincident with these characteristics in strain Or191. In addition to the ability of all of these strains to nodulate alfalfa (Medicago sativa) inefficiently, the AT isolates also nodulated the common bean and Leucaena leucocephala, showing an extended host range for nodulation of legumes. In alfalfa, the time course of nodule formation by the AT isolate LPU 83 showed a continued nodulation restricted to the emerging secondary roots, which was probably related to the low rate of nitrogen fixation by the largely ineffective nodules. Results demonstrate the complexity of the rhizobial populations present in the acidic soils represented by a main group of N2-fixing rhizobia and a second group of ineffective and less-predominant isolates related to the AT strain Or191. PMID:10103231

A CATALOG OF ULTRA-COMPACT HIGH VELOCITY CLOUDS FROM THE ALFALFA SURVEY: LOCAL GROUP GALAXY CANDIDATES?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adams, Elizabeth A. K.; Giovanelli, Riccardo; Haynes, Martha P., E-mail: betsey@astro.cornell.edu, E-mail: riccardo@astro.cornell.edu, E-mail: haynes@astro.cornell.edu

2013-05-01

We present a catalog of 59 ultra-compact high velocity clouds (UCHVCs) extracted from the 40% complete ALFALFA HI-line survey. The ALFALFA UCHVCs have median flux densities of 1.34 Jy km s{sup -1}, median angular diameters of 10', and median velocity widths of 23 km s{sup -1}. We show that the full UCHVC population cannot easily be associated with known populations of high velocity clouds. Of the 59 clouds presented here, only 11 are also present in the compact cloud catalog extracted from the commensal GALFA-HI survey, demonstrating the utility of this separate dataset and analysis. Based on their sky distributionmore » and observed properties, we infer that the ALFALFA UCHVCs are consistent with the hypothesis that they may be very low mass galaxies within the Local Volume. In that case, most of their baryons would be in the form of gas, and because of their low stellar content, they remain unidentified by extant optical surveys. At distances of {approx}1 Mpc, the UCHVCs have neutral hydrogen (H I) masses of {approx}10{sup 5}-10{sup 6} M{sub Sun }, H I diameters of {approx}2-3 kpc, and indicative dynamical masses within the H I extent of {approx}10{sup 7}-10{sup 8} M{sub Sun }, similar to the Local Group ultra-faint dwarf Leo T. The recent ALFALFA discovery of the star-forming, metal-poor, low mass galaxy Leo P demonstrates that this hypothesis is true in at least one case. In the case of the individual UCHVCs presented here, confirmation of their extragalactic nature will require further work, such as the identification of an optical counterpart to constrain their distance.« less

Prohexadione-calcium rate and timing effects on alfalfa interseeded into silage corn

USDA-ARS?s Scientific Manuscript database

Prohexadione-Ca (PHD) can enhance establishment of alfalfa (Medicago sativa, L.) interseeded into silage corn (Zea mays, L.), but optimal application rates and timing for this growth regulator are unknown. Two experiments examined how single or split applications of 0.25 to 1.0 kg a.i. ha-1 of PHD o...

The Undergraduate ALFALFA Team: Outcomes for Over 250 Undergraduate Participants

NASA Astrophysics Data System (ADS)

Troischt, Parker; Koopmann, Rebecca A.; Haynes, Martha P.; ALFALFA Team

2016-01-01

The NSF-sponsored Undergraduate ALFALFA (Arecibo Legacy Fast ALFA) Team (UAT) is a consortium of 19 institutions founded to promote undergraduate research and faculty development within the extragalactic ALFALFA HI blind survey project and follow-up programs. In this talk we present outcomes for the more than 250 undergraduate students who have who have participated in the program during the 8 years of funding. 40% of these students have been women and members of underrepresented groups. To date 148 undergraduate students have attended annual workshops at Arecibo Observatory, interacting with faculty, graduate students, their peers, and Arecibo staff in lectures, group activities, tours, and observing runs. Team faculty have supervised 159 summer research projects and 120 academic year (e.g., senior thesis) projects. 68 students have traveled to Arecibo Observatory for observing runs and 55 have presented their results at national meetings such as the AAS. Through participation in the UAT, students are made aware of career paths they may not have previously considered. More than 90% of alumni are attending graduate school and/or pursuing a career in STEM. 42% of those pursuing graduate degrees in Physics or Astronomy are women. This work has been supported by NSF grants AST-0724918/0902211, AST-075267/0903394, AST-0725380, and AST-1211005

[Composition diversity of lactic acid bacteria (LAB) community Al2 used for alfalfa silage].

PubMed

Wang, Xiao-Fen; Gao, Li-Juan; Yang, Hong-Yan; Wang, Wei-Dong; Cui, Zong-Jun

2006-10-01

Alfalfa is the most important forage grass that is difficult to ensile for good quality. Using silage inoculants are the important way for preservation of alfalfa silage. Through continuous restricted subcultivation, a lactic acid bacteria (LAB) community Al2 was selected from well-fermented alfalfa silage. Plate isolation and Denaturing Gradient Gel Electrophoresis (DGGE), construction of 16S rDNA clone library were used to identify the composition diversity of Al2 community, with 7 strains detected, and they were all belonged to Lactobacillus. The composition ratios of the 7 strains were 55.21%, 19.79%, 14.58%, 3.13%, 3.13%, 3.13%, 1.03% according to 16S rDNA clone library. Al2-1i, Al2-2i, Al2-3i, corresponding to L. plantarum (99.9%), L. kimchii (99.4%), L. farciminis (100%) were detected by plate isolation. Among 3 isolates, Al2-1i had the highest ability of dropping pH and producing lactic acid, and the amount of lactic acid was reach to 18g/L at 24h cultivated in MRS media. The ability of dropping pH and producing lactic acid of Al2-3i was the lowest. From DGGE profiles, the dominant strains in Al2 community were L. plantarum and L. kimchii. L. plantarum was detected during the whole process, and L. kimchii was detected in the later phase.

[Response of alfalfa seed to stress storage conditions].

PubMed

Li, Chunjie; Wang, Yanrong; Zhu, Tingheng; Yu, Ling

2002-08-01

The seed germination rate, seed mortality, seedling length, and infection rate of alfalfa (Medicago sativa L. cv. 'Longdong') were measured at constant temperature 20 degrees C every 60 days during one year storage period after inoculated or no inoculated by Fusarium avenaceum under room temperature (RT), 35 degrees C, and 35 degrees C and +10% seed moisture content (SMC) conditions. Field emergence rates of seeds under above treatments were also observed, and seed-borne fungi were detected under the conditions mentioned above and controlled deterioration (CD) as well. The results showed that the percentage of isolated alfalfa seed-borne fungi was increased from 10% under room temperature and 35 degrees C to 29% under 35 degrees C + 10% SMC. Disease resistance was declined, and seed mortality and seedling infection rate under 35 degrees C + 10% SMC were significantly higher than those under room temperature and 35 degrees C respectively (P < 0.05). The seed germination rate and field emergence rate were also decreased significantly (P < 0.05). Seedling shoot and root length under 35 degrees C + 10% SMC were significantly less than those under RT and 35 degrees C respectively (P < 0.05). The percentages of both seed-borne fungi isolated and field emergence were decreased, and that of seedling infection was increased with storage period extending from 60 to 360 days. Compared to no inoculated control, the percentage of seed germination, seedling shoot and root length were decreased, and seed mortality and seedling infection rate were increased after inoculated by F. avenaceum.

Environmental life cycle assessment of producing willow, alfalfa and straw from spring barley as feedstocks for bioenergy or biorefinery systems.

PubMed

Parajuli, Ranjan; Knudsen, Marie Trydeman; Djomo, Sylvestre Njakou; Corona, Andrea; Birkved, Morten; Dalgaard, Tommy

2017-05-15

The current study aimed at evaluating potential environmental impacts for the production of willow, alfalfa and straw from spring barley as feedstocks for bioenergy or biorefinery systems. A method of Life Cycle Assessment was used to evaluate based on the following impact categories: Global Warming Potential (GWP 100 ), Eutrophication Potential (EP), Non-Renewable Energy (NRE) use, Agricultural Land Occupation (ALO), Potential Freshwater Ecotoxicity (PFWTox) and Soil quality. With regard to the methods, soil organic carbon (SOC) change related to the land occupation was calculated based on the net carbon input to the soil. Freshwater ecotoxicity was calculated using the comparative toxicity units of the active ingredients and their average emission distribution fractions to air and freshwater. Soil quality was based on the change in the SOC stock estimated during the land use transformation and land occupation. Environmental impacts for straw were economically allocated from the impacts obtained for spring barley. The results obtained per ton dry matter showed a lower carbon footprint for willow and alfalfa compared to straw. It was due to higher soil carbon sequestration and lower N 2 O emissions. Likewise, willow and alfalfa had lower EP than straw. Straw had lowest NRE use compared to other biomasses. PFWTox was lower in willow and alfalfa compared to straw. A critical negative effect on soil quality was found with the spring barley production and hence for straw. Based on the energy output to input ratio, willow performed better than other biomasses. On the basis of carbohydrate content of straw, the equivalent dry matter of alfalfa and willow would be requiring higher. The environmental impacts of the selected biomasses in biorefinery therefore would differ based on the conversion efficiency, e.g. of the carbohydrates in the related biorefinery processes. Copyright © 2017 Elsevier B.V. All rights reserved.

The wheat NHX antiporter gene TaNHX2 confers salt tolerance in transgenic alfalfa by increasing the retention capacity of intracellular potassium.

PubMed

Zhang, Yan-Min; Zhang, Hong-Mei; Liu, Zi-Hui; Li, Hui-Cong; Guo, Xiu-Lin; Li, Guo-Liang

2015-02-01

Previous studies have shown that TaNHX2 transgenic alfalfa (Medicago sativa L.) accumulated more K(+) and less Na(+) in leaves than did the wild-type plants. To investigate whether the increased K(+) accumulation in transgenic plants is attributed to TaNHX2 gene expression and whether the compartmentalization of Na(+) into vacuoles or the intracellular compartmentalization of potassium is the critical mechanism for TaNHX2-dependent salt tolerance in transgenic alfalfa, aerated hydroponic culture was performed under three different stress conditions: control condition (0.1 mM Na(+) and 6 mM K(+) inside culture solution), K(+)-sufficient salt stress (100 mM NaCl and 6 mM K(+)) and K(+)-insufficient salt stress (100 mM NaCl and 0.1 mM K(+)). The transgenic alfalfa plants had lower K(+) efflux through specific K(+) channels and higher K(+) absorption through high-affinity K(+) transporters than did the wild-type plants. Therefore, the transgenic plants had greater K(+) contents and [K(+)]/[Na(+)] ratios in leaf tissue and cell sap. The intracellular compartmentalization of potassium is critical for TaNHX2-induced salt tolerance in transgenic alfalfa.

Concurrent synthesis and release of nod-gene-inducing flavonoids from alfalfa roots. [Medicago sativa L. ; Rhizobium meliloti

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maxwell, C.A.; Phillips, D.A.

Flavonoid signals from alfalfa (Medicago sativa L.) induce transcription of nodulation (nod) genes in Rhizobium meliloti. Alfalfa roots release three major nod-gene inducers: 4{prime},7-dihydroxyflavanone, 4{prime},7-dihydroxyflavone, and 4,4{prime}-dihydroxy-2{prime}-methoxychalcone. The objective of the present study was to define temporal relationships between synthesis and exudation for those flavonoids. Requirements for concurrent flavonoid biosynthesis were assessed by treating roots of intact alfalfa seedlings with (U-{sup 14}C)-L-phenylalanine in the presence or absence of the phenylalanine ammonia-lyase inhibitor L-2-aminoxy-3-phenylpropionic acid (AOPP). In the absence of AOPP, each of the three flavonoids in exudates contained {sup 14}C. In the presence of AOPP, {sup 14}C labeling and releasemore » of all the exuded nod-gene inducers were reduced significantly. AOPP inhibited labeling and release of the strongest nod-gene inducer, methoxychalcone, by more than 90%. The release process responsible for exudation of nod-gene inducers appears to be specific rather than a general phenomenon such as a sloughing off of cells during root growth.« less

Task Force II: Energy and Its Socioeconomic Impacts

ERIC Educational Resources Information Center

Appalachia, 1977

1977-01-01

Summarizing the Task Force Issues Paper presented at the Appalachian Conference on Balanced Growth and Economic Development (1977), this article presents selected comments by Task Force participants, and Task Force recommendations re: a national severence tax on extraction of nonrenewable energy resources; socioeconomic costs of nuclear energy; a…

Toxic effects of copper-based nanoparticles or compounds to lettuce (Lactuca sativa) and alfalfa (Medicago sativa).

PubMed

Hong, Jie; Rico, Cyren M; Zhao, Lijuan; Adeleye, Adeyemi S; Keller, Arturo A; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L

2015-01-01

The increased production and use of nanoparticles (NPs) has generated concerns about their impact on living organisms. In this study, nCu, bulk Cu, nCuO, bulk CuO, Cu(OH)2 (CuPRO 2005, Kocide 3000), and CuCl2 were exposed for 15 days to 10 days-old hydroponically grown lettuce (Lactuca sativa) and alfalfa (Medicago sativa). Each compound was applied at 0, 5, 10, and 20 mg L(-1). At harvest, we measured the size of the plants and determined the concentration of Cu, macro and microelements by using ICP-OES. Catalase and ascorbate peroxidase activity was also determined. Results showed that all Cu NPs/compounds reduced the root length by 49% in both plant species. All Cu NPs/compounds increased Cu, P, and S (>100%, >50%, and >20%, respectively) in alfalfa shoots and decreased P and Fe in lettuce shoot (>50% and >50%, respectively, excluding Fe in CuCl2 treatment). Biochemical assays showed reduced catalase activity in alfalfa (root and shoot) and increased ascorbate peroxidase activity in roots of both plant species. Results suggest that Cu NPs/compounds not only reduced the size of the plants but altered nutrient content and enzyme activity in both plant species.

Micromonospora from nitrogen fixing nodules of alfalfa (Medicago sativa L.). A new promising Plant Probiotic Bacteria.

PubMed Central

Martínez-Hidalgo, Pilar; Galindo-Villardón, Purificación; Igual, José M.; Martínez-Molina, Eustoquio

2014-01-01

Biotic interactions can improve agricultural productivity without costly and environmentally challenging inputs. Micromonospora strains have recently been reported as natural endophytes of legume nodules but their significance for plant development and productivity has not yet been established. The aim of this study was to determine the diversity and function of Micromonospora isolated from Medicago sativa root nodules. Micromonospora-like strains from field alfalfa nodules were characterized by BOX-PCR fingerprinting and 16S rRNA gene sequencing. The ecological role of the interaction of the 15 selected representative Micromonospora strains was tested in M. sativa. Nodulation, plant growth and nutrition parameters were analyzed. Alfalfa nodules naturally contain abundant and highly diverse populations of Micromonospora, both at the intra- and at interspecific level. Selected Micromonospora isolates significantly increase the nodulation of alfalfa by Ensifer meliloti 1021 and also the efficiency of the plant for nitrogen nutrition. Moreover, they promote aerial growth, the shoot-to-root ratio, and raise the level of essential nutrients. Our results indicate that Micromonospora acts as a Rhizobia Helper Bacteria (RHB) agent and has probiotic effects, promoting plant growth and increasing nutrition efficiency. Its ecological role, biotechnological potential and advantages as a plant probiotic bacterium (PPB) are also discussed. PMID:25227415

Micromonospora from nitrogen fixing nodules of alfalfa (Medicago sativa L.). A new promising Plant Probiotic Bacteria.

PubMed

Martínez-Hidalgo, Pilar; Galindo-Villardón, Purificación; Trujillo, Martha E; Igual, José M; Martínez-Molina, Eustoquio

2014-09-17

Biotic interactions can improve agricultural productivity without costly and environmentally challenging inputs. Micromonospora strains have recently been reported as natural endophytes of legume nodules but their significance for plant development and productivity has not yet been established. The aim of this study was to determine the diversity and function of Micromonospora isolated from Medicago sativa root nodules. Micromonospora-like strains from field alfalfa nodules were characterized by BOX-PCR fingerprinting and 16S rRNA gene sequencing. The ecological role of the interaction of the 15 selected representative Micromonospora strains was tested in M. sativa. Nodulation, plant growth and nutrition parameters were analyzed. Alfalfa nodules naturally contain abundant and highly diverse populations of Micromonospora, both at the intra- and at interspecific level. Selected Micromonospora isolates significantly increase the nodulation of alfalfa by Ensifer meliloti 1021 and also the efficiency of the plant for nitrogen nutrition. Moreover, they promote aerial growth, the shoot-to-root ratio, and raise the level of essential nutrients. Our results indicate that Micromonospora acts as a Rhizobia Helper Bacteria (RHB) agent and has probiotic effects, promoting plant growth and increasing nutrition efficiency. Its ecological role, biotechnological potential and advantages as a plant probiotic bacterium (PPB) are also discussed.

Soil decontamination of 2,4,6- trinitrotoluene by alfalfa (Medicago sativa).

PubMed

Fallahi, S; Habibi-Rezaei, M; Khayami, M; Heydari, R

2007-12-15

Present study investigate the toxicity effect of 2,4,6-trinitrotoluene (TNT) on a terrestrial plant, alfalfa (Medicago sativa) in artificial soils. In this study, TNT toxicity assessment was performed on spiked silica with this nitroaromatic compound by determination of the percent of emergence and shoots and roots biomasses at the concentration range of 3.2-10000 mg kg(-1) Dry Weight (DW). The emergence was reduced by 22-32% after 5 days of exposure at TNT concentrations up to 100 mg kg(-1) DW; shoot and root biomasses were reduced by 48-50 and 63-74%, respectively after 30 days exposure at TNT concentrations < or = 32 mg kg(-1) DW. Concentrations higher than 100 mg kg(-1) DW can not be tolerated at all. Concentrations of TNT and its metabolites in silica, root and shoot were measured by High-Performance Liquid Chromatography (HPLC). Analyses of TNT spiked soil extracts reveal hat during alfalfa cultivation for 30 days, TNT was partially transformed at the extent of 15-27%. This transformation decreased at higher TNT soil concentrations. TNT is taken up and metabolized by plants to its downstream derivatives.

Variation of directional reflectance factors with structural changes of a developing alfalfa canopy

NASA Technical Reports Server (NTRS)

Kirchner, J. A.; Kimes, D. S.; Mcmurtrey, J. E., III

1982-01-01

Directional reflectance factors of an alfalfa canopy were determined and related to canopy structure, agronomic variables, and irradiance conditions at four periods during a cutting cycle. Nadir and off-nadir reflectance factors decreased with increasing biomass in Thematic Mapper band 3(0.63-0.69 micrometer) and increased with increasing biomass in band 4(0.76-0.90 micrometer). The sensor view angle had less impact on perceived reflectance as the alfalfa progressed from an erectophile canopy of stems after harvest to a near planophile canopy of leaves at maturity. Studies of directional reflectance are needed for testing and upgrading vegetation canopy models and to aid in the complex interpretation problems presented by aircraft scanners and pointable satellites where illumination and viewing geometries may vary widely. Distinct changes in the patterns of radiance observed by a sensor as structural and biomass changes occur are keys to monitoring the growth and condition of crops.

Ractopamine up take by alfalfa (Medicago sativa) and wheat (Triticum aestivum) from soil.

PubMed

Shelver, Weilin L; DeSutter, Thomas M

2015-08-01

Ractopamine is a beta adrenergic agonist used as a growth promoter in swine, cattle and turkeys. To test whether ractopamine has the potential to accumulate in plants grown in contaminated soil, a greenhouse study was conducted with alfalfa (Medicago sativa) and wheat (Triticum aestivum) grown in two soils having different concentrations of organic matter (1.3% and 2.1%), amended with 0, 0.5, and 10 μg/g of ractopamine. Plant growth ranged from 2.7 to 8.8 g dry weight (dw) for alfalfa, and 8.7 to 40 g dw for wheat and was generally greater in the higher organic matter content soil. The uptake of ractopamine in plant tissues ranged from non-detectable to 897 ng/g and was strongly dependent on soil ractopamine concentration across soil and plant tissue. When adjusted to the total fortified quantities, the amount of ractopamine taken up by the plant tissue was low, <0.01% for either soil. Copyright © 2015. Published by Elsevier B.V.

Chloroxyanion Residue on Seeds and Sprouts after Chlorine Dioxide Sanitation of Alfalfa Seed.

PubMed

Smith, David J; Herges, Grant R

2018-02-28

The effects of a 6-h chlorine dioxide sanitation of alfalfa seed (0, 50, 100, and 200 mg/kg seed) on total coliform bacteria, seed germination, and the presence of chlorate and perchlorate residues in seed rinse, seed soak, and alfalfa sprouts was determined. Chlorate residues in 20,000 mg/L calcium hypochlorite, commonly used to disinfect seed, were quantified. Chlorine dioxide treatment reduced (P < 0.05) total coliforms on seeds with no effect (P > 0.05) on germination. Dose-dependent sodium chlorate residues were present in seed rinse (4.1 to 31.2 μg/g seed) and soak (0.7 to 8.3 μg/g seed) waters, whereas chlorate residues were absent (LOQ 5 ng/g) in sprouts, except for 2 of 5 replicates from the high chlorine dioxide treatment. Copious chlorate residues were present (168 to 1260 mg/L) in freshly prepared 20,000 mg/L calcium hypochlorite solution, and storage at room temperature increased chlorate residues significantly (P < 0.01).

Inactivation of Escherichia coli O157:H7 and Salmonella typhimurium DT 104 on alfalfa seeds by levulinic acid and sodium dodecyl sulfate.

PubMed

Zhao, Tong; Zhao, Ping; Doyle, Michael P

2010-11-01

Studies were conducted to determine the best concentration and exposure time for treatment of alfalfa seeds with levulinic acid plus sodium dodecyl sulfate (SDS) to inactivate Escherichia coli O157:H7 and Salmonella without adversely affecting seed germination. Alfalfa seeds inoculated with a five-strain mixture of E. coli O157:H7 or Salmonella Typhimurium were dried in a laminar flow hood at 21°C for up to 72 h. Inoculated alfalfa seeds dried for 4 h then treated for 5 min at 21°C with 0.5% levulinic acid and 0.05% SDS reduced the population of E. coli O157:H7 and Salmonella Typhimurium by 5.6 and 6.4 log CFU/g, respectively. On seeds dried for 72 h, treatment with 0.5% levulinic acid and 0.05% SDS for 20 min at 21°C reduced E. coli O157:H7 and Salmonella Typhimurium populations by 4 log CFU/g. Germination rates of alfalfa seeds treated with 0.5% levulinic acid plus 0.05% SDS for up to 1 h at 21°C were compared with a treatment of 20,000 ppm of calcium hypochlorite or tap water only. Treatment of alfalfa seeds with 0.5% levulinic acid plus 0.05% SDS for 5 min at 21°C resulted in a >3.0-log inactivation of E. coli O157:H7 and Salmonella.

Overexpression of a novel salt stress-induced glycine-rich protein gene from alfalfa causes salt and ABA sensitivity in Arabidopsis.

PubMed

Long, Ruicai; Yang, Qingchuan; Kang, Junmei; Zhang, Tiejun; Wang, Huimin; Li, Mingna; Zhang, Ze

2013-08-01

We cloned a novel salt stress-induced glycine-rich protein gene ( MsGRP ) from alfalfa. Its overexpression retards seed germination and seedling growth of transgenic Arabidopsis after salt and ABA treatments. Since soil salinity is one of the most significant abiotic stresses, salt tolerance is required to overcome salinity-induced reductions in crop productivity. Many glycine-rich proteins (GRPs) have been implicated in plant responses to environmental stresses, but the function and importance of some GRPs in stress responses remain largely unknown. Here, we report on a novel salt stress-induced GRP gene (MsGRP) that we isolated from alfalfa. Compared with some glycine-rich RNA-binding proteins, MsGRP contains no RNA recognition motifs and localizes in the cell membrane or cell wall according to the subcellular localization result. MsGRP mRNA is induced by salt, abscisic acid (ABA), and drought stresses in alfalfa seedlings, and its overexpression driven by a constitutive cauliflower mosaic virus-35S promoter in Arabidopsis plants confers salinity and ABA sensitivity compared with WT plants. MsGRP retards seed germination and seedling growth of transgenic Arabidopsis plants after salt and ABA treatments, which implies that MsGRP may affect germination and growth through an ABA-dependent regulation pathway. These results provide indirect evidence that MsGRP plays important roles in seed germination and seedling growth of alfalfa under some abiotic stress conditions.

First report of Alfalfa mosaic virus infecting basil (Ocimum basilicum L.) in California.

USDA-ARS?s Scientific Manuscript database

Basil (Ocimum basilicum L.) plants collected from a field in Imperial County, CA in May, 2011 were found to exhibit yellowing, chlorotic sectors and spots on leaves, resulting in plants being unmarketable. Total nucleic acid was extracted from plants and tested by RT-PCR for the presence of Alfalfa...

Effects of wrapping time delays on the nutritive value of baled alfalfa silages

USDA-ARS?s Scientific Manuscript database

Baled silages are an attractive forage conservation option, especially for small and mid-sized beef and dairy producers. Our objectives were to test the effects of delayed wrapping on the nutritive value of baled alfalfa silages on a pre- and post-storage basis. A secondary objective was to evaluate...

Alfalfa interseeded into silage corn can enhance productivity and soil and water conservation

USDA-ARS?s Scientific Manuscript database

Alfalfa and corn silage are widely planted for dairy forage production systems throughout the northern regions of the USA, accounting for about 0.8 and 1.9 million hectares per year, respectively. Much of this area could benefit from strategies to reduce soil erosion and nutrient losses. Because the...

Effect of surface roughness on inactivation of Escherichia coli O157:H7 87-23 by new organic acid-surfactant combinations on alfalfa, broccoli, and radish seeds.

PubMed

Fransisca, Lilia; Feng, Hao

2012-02-01

Surface roughness has been reported as one of the factors affecting microbial attachment and removal. Seed surfaces are complex, and different seed varieties have different surface topographies. As a result, a sanitizer effective in eliminating pathogenic bacteria on one seed may not be as effective when applied to another seed. The objectives of this research were (i) to investigate the efficacy of malic acid and thiamine dilaurylsulfate (TDS) combined treatments for inactivation of E. coli O157:H7 strain 87-23 on alfalfa, broccoli, and radish seeds, (ii) to quantify surface roughness of the seeds, and (iii) to determine the correlation between microbial removal and surface roughness. The surface roughness of each seed type was measured by confocal laser scanning microscopy (CLSM) and surface profilometry. Surface roughness (Ra) values of the seeds were then calculated from CLSM data. Seeds inoculated with E. coli O157:H7 87-23 were washed for 20 min in malic acid and TDS solutions and rinsed for 10 min in tap water. Radish seeds had the highest Ra values, followed by broccoli and alfalfa seeds. A combination of 10% malic acid and 1% TDS was more effective than 20,000 ppm of Ca(OCl)(2) for inactivation of E. coli O157:H7 87-23 on broccoli seeds, while the inactivation on radish and alfalfa seeds was not significantly different compared with the 20,000-ppm Ca(OCl)(2) wash. Overall, a negative correlation existed between the seeds' Ra values and microbial removal. Different seeds had different surface roughness, contributing to discrepancies in the ability of the sanitizers to eliminate E. coli O157:H7 87-23 on the seeds. Therefore, the effectiveness of one sanitizer on one seed type should not be translated to all seed varieties.

Task Analysis Inventories. Series II.

ERIC Educational Resources Information Center

Wesson, Carl E.

This second in a series of task analysis inventories contains checklists of work performed in twenty-two occupations. Each inventory is a comprehensive list of work activities, responsibilities, educational courses, machines, tools, equipment, and work aids used and the products produced or services rendered in a designated occupational area. The…

Variances in nutrient content and yield of alfalfa protein concentrate processed with five methods

USDA-ARS?s Scientific Manuscript database

The demand for protein is growing with increased populations and world affluence. A sustainable and affordable protein source is needed to support the growing aquaculture industry worldwide. Alfalfa produces high levels of protein and provides numerous environmental services, potentially making it a...

A colored petri nets based workload evaluation model and its validation through Multi-Attribute Task Battery-II.

PubMed

Wang, Peng; Fang, Weining; Guo, Beiyuan

2017-04-01

This paper proposed a colored petri nets based workload evaluation model. A formal interpretation of workload was firstly introduced based on the process that reflection of petri nets components to task. A petri net based description of Multiple Resources theory was given by comprehending it from a new angle. A new application of VACP rating scales named V/A-C-P unit, and the definition of colored transitions were proposed to build a model of task process. The calculation of workload mainly has the following four steps: determine token's initial position and values; calculate the weight of directed arcs on the basis of the rules proposed; calculate workload from different transitions, and correct the influence of repetitive behaviors. Verify experiments were carried out based on Multi-Attribute Task Battery-II software. Our results show that there is a strong correlation between the model values and NASA -Task Load Index scores (r=0.9513). In addition, this method can also distinguish behavior characteristics between different people. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of the Insect Growth Regulator, Novaluron on Immature Alfalfa Leafcutting Bees, Megachile rotundata

PubMed Central

Hodgson, Erin W.; Pitts-Singer, Theresa L.; Barbour, James D.

2011-01-01

Alfalfa leafcutting bees, Megachile rotundata F. (Hymenoptera: Megachilidae), are the most common pollinators of alfalfa in the Pacific Northwest. Reports from users of M. rotundata in Idaho, Utah and Colorado have indicated exceptionally poor bee return from fields treated with novaluron to control Lygus spp. Our goal was to evaluate novaluron toxicity to immature M. rotundata using two different possible mechanisms of exposure. One goal was to assess immature mortality via treating nectar-pollen provisions and adults with novaluron. Immature M. rotundata mortality in all novaluron provision dosing treatments was significantly higher than the water or blank controls, providing evidence that novaluron is toxic to progeny in nest cells. The mean cumulative frequency showed that more eggs and 1st–2nd instars died compared to older instars. Female M. rotundata nested similarly in field cages during the field cage experiment; however, there was greater immature mortality in cages where females were fed sugar-water + novaluron compared to sugar-water only. Although females provided adequate provisions, there was a low percentage of egg hatch and larval development when females ingested novaluron before mating and nesting. Novaluron was also present in egg provision of bees collecting resources from novaluron-sprayed plants. At least 84% of progeny died when the females were allowed to mate and nest 24 hours after a novaluron application. Novaluron could be contributing to poor bee return in alfalfa grown for seed. Timely insecticide applications to suppress Lygus spp. is an important consideration to improve ongoing bee health. PMID:21539417

High-quality forage production under salinity by using a salt-tolerant AtNXH1-expressing transgenic alfalfa combined with a natural stress-resistant nitrogen-fixing bacterium.

PubMed

Stritzler, Margarita; Elba, Pagano; Berini, Carolina; Gomez, Cristina; Ayub, Nicolás; Soto, Gabriela

2018-06-20

Alfalfa, usually known as the "Queen of Forages", is the main source of vegetable protein to meat and milk production systems worldwide. This legume is extremely rich in proteins due to its highly efficient symbiotic association with nitrogen-fixing strains. In the last years, alfalfa culture has been displaced to saline environments by other important crops, including major cereals, a fact that has reduced its biomass production and symbiotic nitrogen fixation. In this short communication, we report the high forage production and nutrient quality of alfalfa under saline conditions by alfalfa transformation with the AtNHX1 Na + /H + antiporter and inoculation with the stress-resistant nitrogen-fixing strain Sinorhizobium meliloti B401. Therefore, the incorporation of transgenic traits into salt-sensitive legumes in association with the inoculation with natural stress-resistant isolates could be a robust approach to improve the productivity and quality of these important nitrogen-fixing crops. Copyright © 2018. Published by Elsevier B.V.

Correlation of fermentation characteristics with intake and digestibility of alfalfa silage in gestating ewes

USDA-ARS?s Scientific Manuscript database

Baled silage production provides benefits to farmers because it reduces leaf losses, and requires a shorter wilting time, thereby limiting risks of exposure to rain compared with making hay. Our objective was to investigate the correlation of alfalfa silage fermentation parameters with intake and di...

Regression-kriged soil organic carbon stock changes in manured corn silage-alfalfa production systems

USDA-ARS?s Scientific Manuscript database

Accurately measuring soil organic C (SOC) stock changes over time is essential for verifying agronomic management effects on C sequestration. This study quantified the spatial and temporal changes in SOC stocks on adjacent 65-ha corn silage-alfalfa production fields receiving liquid dairy manure in...

Co-expression of bacterial aspartate kinase and adenylylsulfate reductase genes substantially increases sulfur amino acid levels in transgenic alfalfa (Medicago sativa L.).

PubMed

Tong, Zongyong; Xie, Can; Ma, Lei; Liu, Liping; Jin, Yongsheng; Dong, Jiangli; Wang, Tao

2014-01-01

Alfalfa (Medicago sativa L.) is one of the most important forage crops used to feed livestock, such as cattle and sheep, and the sulfur amino acid (SAA) content of alfalfa is used as an index of its nutritional value. Aspartate kinase (AK) catalyzes the phosphorylation of aspartate to Asp-phosphate, the first step in the aspartate family biosynthesis pathway, and adenylylsulfate reductase (APR) catalyzes the conversion of activated sulfate to sulfite, providing reduced sulfur for the synthesis of cysteine, methionine, and other essential metabolites and secondary compounds. To reduce the feedback inhibition of other metabolites, we cloned bacterial AK and APR genes, modified AK, and introduced them into alfalfa. Compared to the wild-type alfalfa, the content of cysteine increased by 30% and that of methionine increased substantially by 60%. In addition, a substantial increase in the abundance of essential amino acids (EAAs), such as aspartate and lysine, was found. The results also indicated a close connection between amino acid metabolism and the tricarboxylic acid (TCA) cycle. The total amino acid content and the forage biomass tested showed no significant changes in the transgenic plants. This approach provides a new method for increasing SAAs and allows for the development of new genetically modified crops with enhanced nutritional value.

Co-Expression of Bacterial Aspartate Kinase and Adenylylsulfate Reductase Genes Substantially Increases Sulfur Amino Acid Levels in Transgenic Alfalfa (Medicago sativa L.)

PubMed Central

Tong, Zongyong; Xie, Can; Ma, Lei; Liu, Liping; Jin, Yongsheng; Dong, Jiangli; Wang, Tao

2014-01-01

Alfalfa (Medicago sativa L.) is one of the most important forage crops used to feed livestock, such as cattle and sheep, and the sulfur amino acid (SAA) content of alfalfa is used as an index of its nutritional value. Aspartate kinase (AK) catalyzes the phosphorylation of aspartate to Asp-phosphate, the first step in the aspartate family biosynthesis pathway, and adenylylsulfate reductase (APR) catalyzes the conversion of activated sulfate to sulfite, providing reduced sulfur for the synthesis of cysteine, methionine, and other essential metabolites and secondary compounds. To reduce the feedback inhibition of other metabolites, we cloned bacterial AK and APR genes, modified AK, and introduced them into alfalfa. Compared to the wild-type alfalfa, the content of cysteine increased by 30% and that of methionine increased substantially by 60%. In addition, a substantial increase in the abundance of essential amino acids (EAAs), such as aspartate and lysine, was found. The results also indicated a close connection between amino acid metabolism and the tricarboxylic acid (TCA) cycle. The total amino acid content and the forage biomass tested showed no significant changes in the transgenic plants. This approach provides a new method for increasing SAAs and allows for the development of new genetically modified crops with enhanced nutritional value. PMID:24520364

Detection of Salmonella by indicator agar media and PCR as affected by alfalfa seed homogenates and native bacteria.

PubMed

Liao, C-H; Shollenberger, L M

2003-01-01

To investigate and prevent the undesirable effect of native bacteria and alfalfa seed homogenates on detection of Salmonella in alfalfa seeds by indicator agar media and polymerase chain reaction (PCR). The relative sensitivity of five indicator agar media, including modified semisolid RV (MSRV), xylose-lysine-Tergitol 4 (XLT4), Hektoen enteric agar (HEA), brilliant green agar (BGA) and bismuth sulphite agar (BSA), for detection of Salmonella in the presence of a large number of native bacteria from alfalfa seeds was examined. The detection limit as measured by the ratio between the numbers of native bacteria and Salmonella was estimated to be 10(6) to 1 for MSRV and 10(3) to 1 for XLT4, HEA, BGA or BSA. Presence of alfalfa seed homogenates markedly reduced the sensitivity of Salmonella detection by PCR. The minimal number of Salmonella detectable by PCR was determined to be 1-10 and 100-1000 CFU in the absence and presence of seed homogenate, respectively. Application of anti-Salmonella immunomagnetic beads permitted detection of 2-5 CFU of heat-injured cells in 25 g of seeds within 24 h by PCR. The MSRV medium is more sensitive than other indicator agars for detecting a small number of motile Salmonella in samples containing a large number of native bacteria. Application of immunomagnetic beads eliminates the PCR-inhibitory activity of seed homogenates and improves the detection of Salmonella in inoculated seeds. The results generated from this study will aid the seed distributors, sprout growers and public health officials to identify and recall the Salmonella-contaminated seed lots to be used for sprout production.

Transgene silencing of sucrose synthase in alfalfa (Medicago sativa L.) stem vascular tissue suggests a role for invertase in cell wall cellulose synthesis.

PubMed

Samac, Deborah A; Bucciarelli, Bruna; Miller, Susan S; Yang, S Samuel; O'Rourke, Jamie A; Shin, Sanghyun; Vance, Carroll P

2015-12-01

Alfalfa (Medicago sativa L.) is a widely adapted perennial forage crop that has high biomass production potential. Enhanced cellulose content in alfalfa stems would increase the value of the crop as a bioenergy feedstock. We examined if increased expression of sucrose synthase (SUS; EC 2.4.1.13) would increase cellulose in stem cell walls. Alfalfa plants were transformed with a truncated alfalfa phosphoenolpyruvate carboxylase gene promoter (PEPC7-P4) fused to an alfalfa nodule-enhanced SUS cDNA (MsSUS1) or the β-glucuronidase (GUS) gene. Strong GUS expression was detected in xylem and phloem indicating that the PEPC7-P4 promoter was active in stem vascular tissue. In contrast to expectations, MsSUS1 transcript accumulation was reduced 75-90 % in alfalfa plants containing the PEPC7-P4::MsSUS1 transgene compared to controls. Enzyme assays indicated that SUS activity in stems of selected down-regulated transformants was reduced by greater than 95 % compared to the controls. Although SUS activity was detected in xylem and phloem of control plants by in situ enzyme assays, plants with the PEPC7-P4::MsSUS1 transgene lacked detectable SUS activity in post-elongation stem (PES) internodes and had very low SUS activity in elongating stem (ES) internodes. Loss of SUS protein in PES internodes of down-regulated lines was confirmed by immunoblots. Down-regulation of SUS expression and activity in stem tissue resulted in no obvious phenotype or significant change in cell wall sugar composition. However, alkaline/neutral (A/N) invertase activity increased in SUS down-regulated lines and high levels of acid invertase activity were observed. In situ enzyme assays of stem tissue showed localization of neutral invertase in vascular tissues of ES and PES internodes. These results suggest that invertases play a primary role in providing glucose for cellulose biosynthesis or compensate for the loss of SUS1 activity in stem vascular tissue.

Growth performance, carcass traits and meat quality of yellow-feathered broilers fed graded levels of alfalfa meal with or without wheat.

PubMed

Jiang, Shouqun; Gou, Zhongyong; Li, Long; Lin, Xiajing; Jiang, Zongyong

2018-03-01

The effects of 0, 40 and 80 g/kg alfalfa meal on growth performance, carcass traits and meat quality of Chinese yellow-feathered broilers fed diets containing or lacking wheat (0 or 200 g/kg) as part of the energy source, were examined using random design with a 2 × 3 factorial arrangement of treatments. Dressing percentage and semi-eviscerated proportion were lower, and meat color a* (redness) value was higher in birds fed diets containing wheat than diets lacking wheat (P < 0.05). Drip loss was reduced by the addition of alfalfa meal to diets containing or lacking wheat (P < 0.05). Average sensory score of breast meat was higher in chickens fed corn-based diets than in those fed wheat (P < 0.05). Meat from those supplemented with 40 g/kg alfalfa meal had better taste than the other two levels (P < 0.05). The inclusion of wheat significantly reduced the activities of creatine kinase and calpain of breast muscle (P < 0.05). In conclusion, Chinese yellow-feathered broilers fed diets containing wheat had better meat color and lower drip loss than those fed the diets without wheat, and adding 40 g/kg alfalfa meal generally improved meat quality and taste. © 2017 Japanese Society of Animal Science.

Statistical analysis of ALFALFA galaxies: Insights in galaxy formation & near-field cosmology

NASA Astrophysics Data System (ADS)

Papastergis, Emmanouil

2013-03-01

The Arecibo Legacy Fast ALFA (ALFALFA) survey is a blind, extragalactic survey in the 21cm emission line of atomic hydrogen (HI). Presently, sources have been cataloged over ≈4,000 deg2 of sky (~60% of its final area), resulting in the largest HI-selected sample to date. We use the rich ALFALFA dataset to measure the statistical properties of HI-bearing galaxies, such as their mass distribution and clustering characteristics. These statistical distributions are determined by the properties of darkmatter on galactic scales, and by the complex baryonic processes through which galaxies form over cosmic time. As a result, detailed studies of these distributions can lead to important insights in galaxy formation & evolution and near-field cosmology. In particular, we measure the space density of HI-bearing galaxies as a function of the width of their HI profile (i.e. the velocity width function of galaxies), and find substantial disagreement with the distribution expected in a lambda cold dark matter (ΛCDM) universe. In particular, the number of galaxies with maximum rotational velocities upsilonrot ≈ 35 kms--1 (as judged by their HI velocity width) is about an order of magnitude lower than what predicted based on populating ΛCDM halos with modeled galaxies. We identify two possible solutions to the discrepancy: First, an alternative dark matter scenario in which the formation of low-mass halos is heavily suppressed (e.g. a warm dark matter universe with keV-scale dark matter particles). Secondly, we consider the possibility that rotational velocitites of dwarf galaxies derived from HI velocity widths may systematically underestimate the true mass of the host halo, due to the shape of their rotation curves. In this latter scenario, quantitative predictions for the internal kinematics of dwarf galaxies can be made, which can be checked in the future to probe the nature of dark matter. Furthermore, we take advantage of the overlap of ALFALFA with the Sloan Digital

The effect of Zn2+ on glucose 6-phosphate dehydrogenase activity from Bufo arenarum toad ovary and alfalfa plants.

PubMed

Fonovich de Schroeder, Teresa M

2005-02-01

The effect of Zn2+ on glucose 6-phosphate dehydrogenase (G6PD) activity was monitored in samples from Bufo arenarum toad ovary and alfalfa plants, in the search for a possible new bioindicator able to detect levels of exposure through contaminated soils, and also to elucidate possible similarities between the enzyme from animal and plant tissues. The in vivo effect was evaluated after exposure of the toads to the metal in Ringer solution during 30 days and after 10 days of treatment in 6 weeks old plants, cultured under laboratory conditions. In vitro effects were measured in different extracts from control samples and partially purified enzyme from ovarian tissue as well as in different extracts from control alfalfa plants, by addition of the metal to the reaction mixture containing the enzyme. G6PD from toad ovary was noncompetitively inhibited by zinc both in vivo and in vitro, under all the experimental conditions studied. A kinetic analysis of the enzyme activity showed that the Michaelis-Menten constant (Km) was not modified, while maximal velocity (Vmax) decreased as the consequence of treatment. It was not possible to obtain a dose-response curve for the effects of Zn2+ on G6PD from alfalfa whole plants, measured in vivo or in vitro. Only leaf extracts evidenced a possible relationship between treatment with the metal and G6PD activity alteration. The results agree with a possible role for G6PD as a biomarker of effect and exposure to Zn2+ in B. arenarum ovarian tissue but not in alfalfa plants.

Replacement of alfalfa hay (Medicago sativa L.) with subabul (Leucaena leucocephala) leaf meal in diets of Najdi goats: effect on digestion activity of rumen microorganisms.

PubMed

Mohammadabadi, Tahereh; Jolazadeh, Alireza

2017-08-01

This study investigated the effect of replacing alfalfa hay by subabul leaf meal (SLM) on digestion, fermentation parameters and rumen bacteria and fungi activity of Najdi goats. Six Najdi goats (150 ± 15 days of age and initial body weight of 35 ± 1.1 kg) were randomly assigned to one of two dietary treatments in a balanced completely randomized design (three goats per treatment) for 56 days. Experimental treatments included alfalfa hay as control group and diet containing SLM (SLM replacing alfalfa hay at 50% level). Bacterial and fungi activity and rumen fermentation parameters of animals fed experimental diets were determined. Dry matter disappearance (DMD) was unaffected by replacing SLM with alfalfa hay for both rumen bacteria and fungi in different incubation times, except for 48 h of incubation in specific culture medium of mixed rumen bacteria, which decreased for SLM group (P > 0.05). NDF disappearance (NDFD) and ADF disappearance (ADFD) after 24 and 48 h of incubation in specific culture medium of mixed rumen bacteria was not affected by experimental diets (P > 0.05). However, 72 h after incubation, NDFD in SLM treatment decreased (P > 0.05). Gas production parameters of rumen bacteria were similar for both experimental diets, but partitioning factor (PF), efficiency microbial biomass production (EMBP), microbial protein production (MP), and organic matter truly digested (OMTD) decreased (p < 0.05) in specific culture medium of mixed rumen fungi for SLM diet. There was significant decrease in total protozoa population for diet containing SLM (p < 0.05). Results indicated that replacement of alfalfa hay by SLM had no major effect on rumen microorganisms' activity of Najdi goats, so it may be used as an alternative for alfalfa (at 50% level) in susceptible areas.

From model to crop: functional analysis of a STAY-GREEN gene in the model legume Medicago truncatula and effective use of the gene for alfalfa improvement.

PubMed

Zhou, Chuanen; Han, Lu; Pislariu, Catalina; Nakashima, Jin; Fu, Chunxiang; Jiang, Qingzhen; Quan, Li; Blancaflor, Elison B; Tang, Yuhong; Bouton, Joseph H; Udvardi, Michael; Xia, Guangmin; Wang, Zeng-Yu

2011-11-01

Medicago truncatula has been developed into a model legume. Its close relative alfalfa (Medicago sativa) is the most widely grown forage legume crop in the United States. By screening a large population of M. truncatula mutants tagged with the transposable element of tobacco (Nicotiana tabacum) cell type1 (Tnt1), we identified a mutant line (NF2089) that maintained green leaves and showed green anthers, central carpels, mature pods, and seeds during senescence. Genetic and molecular analyses revealed that the mutation was caused by Tnt1 insertion in a STAY-GREEN (MtSGR) gene. Transcript profiling analysis of the mutant showed that loss of the MtSGR function affected the expression of a large number of genes involved in different biological processes. Further analyses revealed that SGR is implicated in nodule development and senescence. MtSGR expression was detected across all nodule developmental zones and was higher in the senescence zone. The number of young nodules on the mutant roots was higher than in the wild type. Expression levels of several nodule senescence markers were reduced in the sgr mutant. Based on the MtSGR sequence, an alfalfa SGR gene (MsSGR) was cloned, and transgenic alfalfa lines were produced by RNA interference. Silencing of MsSGR led to the production of stay-green transgenic alfalfa. This beneficial trait offers the opportunity to produce premium alfalfa hay with a more greenish appearance. In addition, most of the transgenic alfalfa lines retained more than 50% of chlorophylls during senescence and had increased crude protein content. This study illustrates the effective use of knowledge gained from a model system for the genetic improvement of an important commercial crop.

Canopy visible and near-infrared reflectance data to estimate alfalfa nutritive attributes before harvest

USDA-ARS?s Scientific Manuscript database

Proximal sensing could help improve profit margins by timing the cutting or harvesting of alfalfa (Medicago sativa L.), in rapid assessment of nutritive values, such as total nitrogen (N), neutral detergent fiber (NDF), and acid detergent fiber (ADF) as well as nutritive quality indicators such as r...

Foliar fungicides on alfalfa: 2012 University extension field trial results from Minnesota and Wisconsin

USDA-ARS?s Scientific Manuscript database

To answer the increasing number of questions received regarding the use of foliar fungicide on alfalfa, a group of Extension and USDA Agricultural Research Station staff in southeastern Minnesota and Wisconsin worked together to conduct field research trials to examine the benefit of using a foliar ...

Contribution of the pod wall to seed grain filling in alfalfa.

PubMed

Wang, Hui; Hou, Longyu; Wang, Mingya; Mao, Peisheng

2016-05-23

Three genotypes of alfalfa viz. Medicago sativa (Zhongmu No. 1, Zhongmu No. 2) and M. varia (Caoyuan No. 3) grown in the filed were investigated for the contribution of pod wall and leaves by shading all pods and leaves on July 15, 20 and 25, respectively. Date was recorded for total pod weight (TPW), pod wall weight (PWW), seed weight per pod (SWP), seed number per pod (SNP) and single seed weight (SSW) of one-coil and two-coil spiral pods. TPW, SNP, PWW and SWP were reduced by shading all leaves or pods, whereas SSW was not significantly affected. The relative photosynthetic contribution of pod wall to SWP was 25.6-48.1% in three genotypes on July 15. The pod wall in one-coil spiral pods generated a greater relative contribution to the TPW and SWP than in two-coil spiral pods. In the last stage (July 25), the relative photosynthetic contribution of leaves to SWP sharply decreased, whereas the relative photosynthetic contribution of pod wall to SWP was stable in the late stage (July 20 and 25). In conclusion, the pod wall of alfalfa could carry out photosynthesis and the pod wall played an important role in pod filling at the late growth stage.

Effects of alfalfa hay and its physical form (chopped versus pelleted) on performance of Holstein calves.

PubMed

Jahani-Moghadam, M; Mahjoubi, E; Hossein Yazdi, M; Cardoso, F C; Drackley, J K

2015-06-01

Inclusion of forage and its physical form in starter may affect rumen development, average daily gain (ADG), and dry matter intake (DMI) of dairy calves. To evaluate the effects of forage and its physical form (chopped vs. pelleted) on growth of calves under a high milk feeding regimen, 32 Holstein calves (38.8±1.1kg) were assigned at birth to 1 of 3 treatments in a completely randomized block design. Dietary treatments (% of dry matter) were (1) 100% semi-texturized starter (CON); (2) 90% semi-texturized starter + 10% chopped alfalfa hay (mean particle size=5.4mm) as a total mixed ration (TMR; CH); and (3) 90% semi-texturized starter + 10% pelleted alfalfa (mean=5.8mm) hay as a TMR (PH). Data were subjected to mixed model analysis with contrasts used to evaluate effect of forage inclusion. Calves were weaned at 76 d of age and the experiment finished 2 wk after weaning. Individual milk and solid feed consumption were recorded daily. Solid feed consumption and ADG increased as age increased (effect of week), but neither forage inclusion nor physical form of forage affected these variables pre- or postweaning. Plasma urea N was affected by treatments such that the CON group had a lower concentration than forage-fed groups. Forage inclusion, but not physical form, resulted in increased total protein in plasma. Although days with elevated rectal temperature, fecal score, and general appearance were not affected by dietary treatments, calves fed alfalfa hay during the first month of life had fewer days with respiratory issues, regardless of physical form of hay. We concluded that provision of forage does have some beneficial effects in calves fed large amounts of milk replacer, but pelleted alfalfa hay did not result in any improvement in calf performance or health. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Elevated Atmospheric CO2 and Strain of Rhizobium Alter Freezing Tolerance and Cold-induced Molecular Changes in Alfalfa (Medicago sativa)

PubMed Central

Bertrand, Annick; Prévost, Danielle; Bigras, Francine J.; Castonguay, Yves

2007-01-01

Background and Aims The objective of the study was to assess the impact of elevated CO2 in interaction with rhizobial strains on freezing tolerance and cold-induced molecular changes in alfalfa. Methods Alfalfa inoculated with two different strains of rhizobium (A2 and NRG34) was grown and cold acclimated (2 weeks at 2 °C) under either 400 (ambient) or 800 µmol mol−1 (elevated) CO2. Key Results Plants acclimated under 400 µmol mol−1 CO2 were more freezing tolerant than those maintained under 800 µmol mol−1. Cryoprotective sugars typically linked with the acquisition of freezing tolerance such as sucrose, stachyose and raffinose increased in roots in response to low temperature but did not differ between CO2 treatments. Similarly high CO2 did not alter the expression of many cold-regulated (COR) genes although it significantly increased the level of transcripts encoding a COR gene homologous to glyceraldehyde-3-phosphate-dehydrogenase (GAPDH). A significant effect of rhizobial strain was observed on both freezing tolerance and gene expression. Plants of alfalfa inoculated with strain A2 were more freezing tolerant than those inoculated with strain NRG34. Transcripts of COR genes homologous to a pathogenesis-related protein (PR-10) and to a nuclear-targeted protein were markedly enhanced in roots of alfalfa inoculated with strain A2 as compared with strain NRG34. Transcripts encoding the vegetative storage proteins (VSPs) β-amylase and chitinase were more abundant in roots of non-acclimated plants inoculated with strain NRG34 than with strain A2. Conclusions Taken together, the results suggest that elevated CO2 stimulates plant growth and reduces freezing tolerance. The acquisition of cold tolerance is also influenced by the rhizobial strain, as indicated by lower levels of expression of COR genes and sustained accumulation of VSP-encoding transcripts in alfalfa inoculated with strain NRG34 as compared with strain A2. PMID:17218341

Molecular improvement of alfalfa for enhanced productivity and adaptability in a changing environment.

PubMed

Singer, Stacy D; Hannoufa, Abdelali; Acharya, Surya

2017-10-18

Due to an expanding world population and increased buying power, the demand for ruminant products such as meat and milk is expected to grow substantially in coming years, and high levels of forage crop production will therefore be a necessity. Unfortunately, urbanization of agricultural land, intensive agricultural practices, and climate change are all predicted to limit crop production in the future, which means that the development of forage cultivars with improved productivity and adaptability will be essential. Because alfalfa (Medicago sativa L.) is one of the most widely cultivated perennial forage crops, it has been the target of much research in this field. In this review, we discuss progress that has been made towards the improvement of productivity, abiotic stress tolerance, and nutrient-use efficiency, as well as disease and pest resistance, in alfalfa using biotechnological techniques. Furthermore, we consider possible future priorities and avenues for attaining further enhancements in this crop as a means of contributing to the realization of food security in a changing environment. © 2017 John Wiley & Sons Ltd.

Carbon use and uptake efficiencies of hayed alfalfa and grassland in a semiarid environment

USDA-ARS?s Scientific Manuscript database

Land use and management practices are key factors that influence net ecosystem exchange (NEE) for carbon dioxide in semiarid regions. We used alfalfa (Medicago sativa L.) and grassland ecosystems in a multi-year study (2009-2013) to determine the daily, seasonal and annual carbon (C) budget, and par...

Amino acid profiles of rumen undegradable protein: a comparison between forages including cereal straws and alfalfa and their respective total mixed rations.

PubMed

Wang, B; Jiang, L S; Liu, J X

2018-06-01

Optimizing the amino acid (AA) profile of rumen undegradable protein (RUP) can positively affect the amount of milk protein. This study was conducted to improve knowledge regarding the AA profile of rumen undegradable protein from corn stover, rice straw and alfalfa hay as well as the total mixed ratio diets (TMR) based on one of them as forage source [forage-to-concentrate ratio of 45:55 (30% of corn stover (CS), 30% of rice straw (RS), 23% of alfalfa hay (AH) and dry matter basis)]. The other ingredients in the three TMR diets were similar. The RUP of all the forages and diets was estimated by incubation for 16 hr in the rumen of three ruminally cannulated lactating cows. All residues were corrected for microbial colonization, which was necessary in determining the AA composition of RUP from feed samples using in situ method. Compared with their original AA composition, the AA pattern of forages and forage-based diets changed drastically after rumen exposure. In addition, the extent of ruminal degradation of analysed AA was not constant among the forages. The greatest individual AA degradability of alfalfa hay and corn stover was Pro, but was His of rice straw. A remarkable difference was observed between microbial attachment corrected and uncorrected AA profiles of RUP, except for alfalfa hay and His in the three forages and TMR diets. The ruminal AA degradability of cereal straws was altered compared with alfalfa hay but not for the TMR diets. In summary, the AA composition of forages and TMR-based diets changed significantly after ruminal exposure, indicating that the original AA profiles of the feed cannot represent its AA composition of RUP. The AA profile of RUP and ruminal AA degradability for corn stover and rice straw contributed to missing information in the field. © 2017 Blackwell Verlag GmbH.

Effect of sequential dry heat and hydrogen peroxide treatment on inactivation of Salmonella Typhimurium on alfalfa seeds and seeds germination.

PubMed

Hong, Eun-Jeong; Kang, Dong-Hyun

2016-02-01

The purpose of this study was to inactivate Salmonella Typhimurium on alfalfa seeds without having negative effect on seed germination. Inoculated alfalfa seeds were treated with dry heat at 60, 70 or 80 °C for 0, 12, 18 or 24 h followed by 2% hydrogen peroxide solution (10 min). Populations of Salmonella on alfalfa seeds treated with dry heat alone (60, 70 or 80 °C) for up to 24 h were reduced by 0.26-2.76 log CFU/g, and sequential treatment with dry heat and H2O2 reduced populations by 1.66-3.60 log CFU/g. The germination percentage of seeds subjected to sequential treatments was significantly enhanced to up to 97%, whereas that of untreated seeds was only 79.5%. This study suggests that sequential treatment with dry heat and hydrogen peroxide is applicable for reducing levels of Salmonella on seeds while simultaneously enhancing seeds germinability. Copyright © 2015. Published by Elsevier Ltd.

Transcriptional regulation of temperature stress response during development in the alfalfa leafcutting bee, Megachile rotundata

USDA-ARS?s Scientific Manuscript database

Insects can be significantly affected by temperature induced stress. While evidence of the physiological consequences of temperature stress is growing, very little is known about how insects respond at the genetic level to these stressors. The alfalfa leafcutting bee, Megachile rotundata, an emergin...

Potential application of high hydrostatic pressure to eliminate Escherichia coli O157:H7 on alfalfa sprouted seeds.

PubMed

Neetoo, Hudaa; Ye, Mu; Chen, Haiqiang

2008-12-10

Sprouts eaten raw are increasingly being perceived as hazardous foods as they have been implicated in Escherichia coli O157:H7 outbreaks where the seeds were found to be the likely source of contamination. The objective of our study was to evaluate the potential of using high hydrostatic pressure (HHP) technology for alfalfa seed decontamination. Alfalfa seeds inoculated with a cocktail of five strains of E. coli O157:H7 were subjected to pressures of 500 and 600 MPa for 2 min at 20 degrees C in a dry or wet (immersed in water) state. Immersing seeds in water during pressurization considerably enhanced inactivation of E. coli O157:H7 achieving reductions of 3.5 log and 5.7 log at 500 and 600 MPa, respectively. When dry seeds were pressurized, both pressure levels reduced the counts by <0.7 log. To test the efficacy of HHP to completely decontaminate seeds whilst meeting the FDA requirement of 5 log reductions, seeds inoculated with a ~5 log CFU/g of E. coli O157:H7 were pressure-treated at 600 and 650 MPa at 20 degrees C for holding times of 2 to 20 min. A >5 log reduction in the population was achieved when 600 MPa was applied for durations of > or =6 min although survivors were still detected by enrichment. When the pressure was stepped up to 650 MPa, the threshold time required to achieve complete elimination was 15 min. Un-inoculated seeds pressure-treated at 650 MPa for 15 min at 20 degrees C successfully sprouted achieving a germination rate identical to untreated seeds after eight days of sprouting. These results therefore demonstrate the promising application of HHP on alfalfa seeds to eliminate the risk of E. coli O157:H7 infections associated with consumption of raw alfalfa sprouts.

Risks and benefits of compost-like materials prepared by the thermal treatment of raw scallop hepatopancreas for supplying cadmium and the growth of alfalfa (Medicago sativa L.).

PubMed

Ushijima, Kensuke; Fukushima, Masami; Kanno, Shinya; Kanno, Itoko; Ohnishi, Mitsuhiro

2016-01-01

Scallop hepatopancreas, fishery waste, contains relatively high levels of Cd and organic nitrogen compounds, the latter of which represent a fertilizer. In this study, raw scallop hepatopancreas tissue was thermally treated with sawdust and red loam in the presence of an iron catalyst to produce compost-like materials (CLMs). Two CLM samples were prepared by varying the content of raw scallop hepatopancreas tissue: 46 wt.% for CLM-1 and 18 wt.% for CLM-2. Mixtures of control soil (CTL) and CLMs (CLM content: 10 and 25 wt.%) were examined for the growth of alfalfa (Medicago sativa L.) to evaluate the risks and benefits of using this material for fertilization. The Cd content in shoots and roots of alfalfa, that were grown in the presence of CLMs, was significantly higher than those for the plants grown in the CTL, indicating that Cd had accumulated in the plants from CLMs. The accumulation of Cd in the alfalfa roots was quite high in the case of the 25% CLM-1 sample. However, alfalfa growth was significantly promoted in the presence of 10% CLM-1. This can be attributed to the higher levels of nitrogen and humic substances, which serve as fertilizer components. Although the fertilization effect in case of CLM-1showed a potential benefit, the accumulation of Cd in alfalfa was clearly increased in the presence of both CLMs. In conclusion, the use of CLMs produced from raw scallop hepatopancreas tissue can be considered to have a desirable benefit from standpoint of its use as fertilizer, but is accompanied by a risk of the accumulation of Cd in alfalfa plants.

Incorporation of p-coumarates into the cell walls of alfalfa changes the lignin composition

USDA-ARS?s Scientific Manuscript database

In general, monocots can contain a significant amount of an ester-linked p-coumarate (pCA) in their cell walls, but its function is unclear. One hypothesis is that pCA aids in the formation of syringyl-rich regions during lignification. Alfalfa (Medicago sativa), a dicot, is a cultivated perennial f...

Using Egocentric Networks to Illustrate Information Seeking and Sharing by Alfalfa Farmers in Wyoming

ERIC Educational Resources Information Center

Noy, Shiri; Jabbour, Randa

2017-01-01

We explored using farmers' egocentric (personal) networks to understand how they seek farming advice and how their advice networks map onto their friendship networks. We examined results from a survey of alfalfa farmers (n = 634) in Wyoming. Farmers reported seeking advice from neighbors and fellow farmers, and most indicated that these people are…

Regulation of glutamine synthetase II activity in Rhizobium meliloti 104A14.

PubMed Central

Shatters, R G; Somerville, J E; Kahn, M L

1989-01-01

Most rhizobia contain two glutamine synthetase (GS) enzymes: GSI, encoded by glnA, and GSII, encoded by glnII. We have found that WSU414, a Rhizobium meliloti 104A14 glutamine auxotroph derived from a glnA parental strain, is an ntrA mutant. The R. meliloti glnII promoter region contains DNA sequences similar to those found in front of other genes that require ntrA for their transcription. No GSII was found in the glnA ntrA mutant, and when a translational fusion of glnII to the Escherichia coli lacZ gene was introduced into WSU414, no beta-galactosidase was expressed. These results indicate that ntrA is required for glnII expression. The ntrA mutation did not prevent the expression of GSI. In free-living culture, the level of GSII and of the glnII-lacZ fusion protein was regulated by altering transcription in response to available nitrogen. No GSII protein was detected in alfalfa, pea, or soybean nodules when anti-GSII-specific antiserum was used. Images PMID:2570059

Behavior of non-O157 Shiga toxin-producing Escherichia coli, enteroinvasive E. coli, enteropathogenic E. coli, and enterotoxigenic E. coli strains on alfalfa sprouts.

PubMed

Gómez-Aldapa, Carlos A; Rangel-Vargas, Esmeralda; Torres-Vitela, M Del Refugio; Villarruel-López, Angélica; Castro-Rosas, Javier

2013-08-01

Data about the behavior of non-O157 Shiga toxin-producing Escherichia coli (non-O157 STEC), enteroinvasive E. coli (EIEC), enterotoxigenic E. coli (ETEC), and enteropathogenic E. coli (EPEC) on seeds and alfalfa sprouts are not available. The behavior of STEC, EIEC, ETEC, and EPEC was determined during germination and sprouting of alfalfa seeds at 20 ± 2°C and 30 ± 2°C and on alfalfa sprouts at 3 ± 2°C. When alfalfa seeds were inoculated with STEC, EIEC, ETEC, or EPEC strains, all these diarrheagenic E. coli pathotypes (DEPs) grew during germination and sprouting of seeds, reaching counts of approximately 5 and 6 log CFU/g after 1 day at 20 ± 2°C and 30 ± 2°C, respectively. However, when the sprouts were inoculated after 1 day of seed germination and stored at 20 ± 2°C or 30 ± 2°C, no growth was observed for any DEP during sprouting at 20 ± 2°C or 30 ± 2°C for 9 days. Refrigeration reduced significantly (P < 0.0.5) the number of viable DEPs on sprouts after 20 days in storage; nevertheless, these decreases have no practical significance for the safety of the sprouts.

Variable salinity responses of 12 alfalfa genotypes and comparative expression analyses of salt-response genes

USDA-ARS?s Scientific Manuscript database

Twelve alfalfa genotypes that were selected for biomass under salinity, differences in Na and Cl concentrations in shoots and K/Na ratio were evaluated in this long-term salinity experiment. The selected plants were cloned to reduce genetic variability within each genotype. Salt tolerance (ST) index...

Effect of an ozone injury retardant chemical on isozyme profiles from alfalfa callus in vitro

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rier, J.P. Jr.; Sood, V.K.; Whitaker, A.

1983-01-01

Plant ozone injury retardant N-(2-(2-oxo-1-imidazolidinyl)-ethyl)-N'-phenylurea (EDU or ethylenediurea) at 1.0 ppm inhibited growth of callus of alfalfa cultivars Williamsburg (ozone-sensitive) and MSB-CW5An2 (ozone-insensitive) germplasm of Medicago sativa. The presence of EDU (0.1 ppm)in the growth medium increased the number of protein and peroxidase isozyme bands in alfalfa cultivar Williamsburg stem callus and ozone modified their intensities. Protein profiles of MSB stem callus from media containing EDU or exposed to ozone were unchanged. Marked differences were observed between the peroxidase profiles of ozonated and control ozone-insensitive stem callus from media containing EDU. Protein profiles of ozonated ozone-sensitive leaf callus differed slightlymore » from controls. The peroxidase profile of ozonated ozone-sensitive leaf callus was not altered when its growth medium contained EDU, but when it was absent, changes were observed in these profiles.« less

A CLIPS expert system for maximizing alfalfa (Medicago Sativa L.) production

NASA Technical Reports Server (NTRS)

Engel, B. A.; Jones, D. D.; Rhykerd, R. L.; Rhykerd, L. M.; Rhykerd, C. L., Jr.; Rhykerd, C. L.

1990-01-01

An alfalfa management expert system originally developed by Purdue University agricultural scientists on the PC Plus expert system shell from Texas Instrument has been updated and successfully converted to CLIPS (C Language Integrated Production System). This reduces the cost and legal restrictions associated with making the expert system available to agribusiness industries, extension personnel and farm managers and operators. The expert system includes recommendations concerning soil drainage, liming, P and K fertilization, weed control, variety selection and seeding rate including pure live seeds.

Alterations in nitrogen metabolites after putrescine treatment in alfalfa under drought stress.

PubMed

Zeid, I M; Shedeed, Z A

2007-05-01

Alfalfa (Medicago sativa, Siwa 1) seeds were subjected to drought stress during germination by using polyethylene glycol (PEG 4000) for studying the changes in some enzyme activities involved in nitrogen metabolism and the content of nitrogenous compounds during the first four days of growth after putrescine (Put) treatment. Decreasing the external water potential reduced activities of glutamate-pyruvate transferase (GPT), glutamate-oxaloacetate transferase (GOT) and RNase. Some free amino acids such as proline and glycine increased, while alanine and aspartic acid decreased. Nucleic acids content also decreased. Polyamines e.g., spermidine (Spd) and spermine (Spm) increased at the water potential -0.4 MPa. Put treatment increased activities of GOT, GPT and RNase. Furthermore, Put treatment increased nucleic acids content and the endogenous polyamines under drought stress. Drought stress was imposed during seedling stage by decreasing soil moisture content. GOT, GPT and RNase activities increased in leaves of alfalfa seedlings under drought stress. Soluble nitrogenous compounds accumulated under drought stress, while nucleic acids content decreased. Except glutamic acid, all free amino acids detected increased under drought stress. Put treatment decreased activities of GOT, GPT and RNase, as well as reduced the accumulation of the total soluble nitrogenous compounds, but increased DNA, RNA and protein contents.

Task Analysis and the Ability Requirements of Tasks: Collected Papers.

DTIC Science & Technology

1981-09-01

Skill. In F. A . Bilodeau (ed.) Acquisition of Skill, New York: Academic Pr.sS, 1066, 147-167. Kennedy, R. S., Bittner, A. C., Jr. & Harbeson, M. M...o.-iL cili * ii It~ ti(-t Iat :iiiss, iil- aind whose tasks ite menitt into- Cilirnori1 risk eLect- ielt ’. T: i s iLu,’ ie r t, r-io-.’I i-i viii d

Antioxidant responses in soybean and alfalfa plants grown in DDTs contaminated soils: Useful variables for selecting plants for soil phytoremediation?

PubMed

Mitton, Francesca M; Ribas Ferreira, Josencler L; Gonzalez, Mariana; Miglioranza, Karina S B; Monserrat, José M

2016-06-01

Phytoremediation is a low-cost alternative technology based on the use of plants to remove pollutants from the environment. Persistent organic pollutants such as DDTs with a long half-life in soils are attractive candidates for remediation. This study aimed to determine the potential of antioxidant response use in the evaluation of plants' tolerance for selecting species in phytoremediation purposes. Alfalfa and soybean plants were grown in DDT contaminated soils. After 60days, growth, protein content, antioxidant capacity, GST activity, concentration of proteic and non-proteic thiol groups, chlorophyll content and carotenoid content were measured in plant tissues. Results showed no effect on alfalfa or soybean photosynthetic pigments but different responses in the protein content, antioxidant capacity, GST activity and thiol groups on roots, stems and leaves, indicating that DDTs affected both species. Soybean showed higher susceptibility than alfalfa plants due to the lower antioxidant capacity and GST activity in leaves, in spite of having the lowest DDT accumulation. This study provides new insights into the role of oxidative stress as an important component of the plant's response to DDT exposure. Copyright © 2015 Elsevier B.V. All rights reserved.

From Model to Crop: Functional Analysis of a STAY-GREEN Gene in the Model Legume Medicago truncatula and Effective Use of the Gene for Alfalfa Improvement1[W][OA

PubMed Central

Zhou, Chuanen; Han, Lu; Pislariu, Catalina; Nakashima, Jin; Fu, Chunxiang; Jiang, Qingzhen; Quan, Li; Blancaflor, Elison B.; Tang, Yuhong; Bouton, Joseph H.; Udvardi, Michael; Xia, Guangmin; Wang, Zeng-Yu

2011-01-01

Medicago truncatula has been developed into a model legume. Its close relative alfalfa (Medicago sativa) is the most widely grown forage legume crop in the United States. By screening a large population of M. truncatula mutants tagged with the transposable element of tobacco (Nicotiana tabacum) cell type1 (Tnt1), we identified a mutant line (NF2089) that maintained green leaves and showed green anthers, central carpels, mature pods, and seeds during senescence. Genetic and molecular analyses revealed that the mutation was caused by Tnt1 insertion in a STAY-GREEN (MtSGR) gene. Transcript profiling analysis of the mutant showed that loss of the MtSGR function affected the expression of a large number of genes involved in different biological processes. Further analyses revealed that SGR is implicated in nodule development and senescence. MtSGR expression was detected across all nodule developmental zones and was higher in the senescence zone. The number of young nodules on the mutant roots was higher than in the wild type. Expression levels of several nodule senescence markers were reduced in the sgr mutant. Based on the MtSGR sequence, an alfalfa SGR gene (MsSGR) was cloned, and transgenic alfalfa lines were produced by RNA interference. Silencing of MsSGR led to the production of stay-green transgenic alfalfa. This beneficial trait offers the opportunity to produce premium alfalfa hay with a more greenish appearance. In addition, most of the transgenic alfalfa lines retained more than 50% of chlorophylls during senescence and had increased crude protein content. This study illustrates the effective use of knowledge gained from a model system for the genetic improvement of an important commercial crop. PMID:21957014

Characterization of the bacterial stem blight pathogen of alfalfa, Pseudomonas syringae pv. syringae ALF3

USDA-ARS?s Scientific Manuscript database

Bacterial stem blight of alfalfa occurs sporadically in the central and western U.S. Yield losses of up to 50% of the first harvest can occur with some cultivars. Developing resistant cultivars is hampered by lack of information on the pathogen and a standard test for evaluating plant germplasm. Bac...

The Baryonic Tully Fisher Relation for the ALFALFA 100 Sample

NASA Astrophysics Data System (ADS)

Finney, Elizabeth E.; Haynes, Martha P.; APPSS Team

2018-01-01

The APPSS (Arecibo Pisces-Perseus Supercluster Survey) team aims to quantify the over-densities of matter in the Pisces-Perseus Supercluster (PPS) filament by exploring the Baryonic Tully Fisher Relation (BTFR) of the ALFALFA (Arecibo Legacy Fast ALFA) 100 survey – (α.100) and, in the future, using targeted observations of low mass star-forming galaxies. Galaxies in the PPS filament region and its foreground and background voids are influenced by the gravitational pull of the large concentration of matter, and are expected to show velocities that deviate significantly from the smooth Hubble expansion. By deriving the peculiar motions of galaxies in the ALFALFA 100 survey as measured by the BTFR, we will further our understanding of the amount and distribution of the underlying dark matter in the supercluster. In this project, we make a first attempt to investigate the BTFR of the α.100 sample, and discuss our findings. This sample was corrected for inclination, extinction, and other sources of scatter, and a least squares linear regression fit was applied to determine the slope of the BTFR. We compare the slope of the α.100 sample to various literature values, and find that the slope is shallower due to slower-rotating, low-mass galaxies. Investigation of this shallow slope is needed in future work, as well as a modification of the intrinsic axial ratio assumed for this sample of galaxies. EF participated in the summer 2017 REU program in the Center for Astrophysics and Planetary Science at Cornell University under NSF award AST-1659264.

Spatiotemporal soil organic carbon dynamics in irrigated corn silage-alfalfa production systems receiving liquid dairy manure

USDA-ARS?s Scientific Manuscript database

Accurately measuring soil organic C (SOC) stock changes over time is essential for verifying agronomic management effects on C sequestration. This study quantified the spatial and temporal changes in SOC stocks on adjacent 65-ha corn silage-alfalfa production fields receiving liquid dairy manure in...

Isolation of Salmonella from alfalfa seed and demonstration of impaired growth of heat-injured cells in seed homogenates.

PubMed

Liao, Ching-Hsing; Fett, William F

2003-05-15

Three major foodborne outbreaks of salmonellosis in 1998 and 1999 were linked to the consumption of raw alfalfa sprouts. In this report, an improved method is described for isolation of Salmonella from alfalfa seed lots, which had been implicated in these outbreaks. From each seed lot, eight samples each containing 25 g of seed were tested for the presence of Salmonella by the US FDA Bacteriological Analytical Manual (BAM) procedure and by a modified method applying two successive pre-enrichment steps. Depending on the seed lot, one to four out of eight samples tested positive for Salmonella by the standard procedure and two to seven out of eight samples tested positive by the modified method. Thus, the use of two consecutive pre-enrichment steps led to a higher detection rate than a single pre-enrichment step. This result indirectly suggested that Salmonella cells on contaminated seeds might be injured and failed to fully resuscitate in pre-enrichment broth containing seed components during the first 24 h of incubation. Responses of heat-injured Salmonella cells grown in buffered peptone water (BPW) and in three alfalfa seed homogenates were investigated. For preparation of seed homogenates, 25 g of seeds were homogenized in 200 ml of BPW using a laboratory Stomacher and subsequently held at 37 degrees C for 24 h prior to centrifugation and filtration. While untreated cells grew at about the same rate in BPW and in seed homogenates, heat-injured cells (52 degrees C, 10 min) required approximately 0.5 to 4.0 h longer to resuscitate in seed homogenates than in BPW. This result suggests that the alfalfa seed components or fermented metabolites from native bacteria hinder the repair and growth of heat-injured cells. This study also shows that an additional pre-enrichment step increases the frequency of isolation of Salmonella from naturally contaminated seeds, possibly by alleviating the toxic effect of seed homogenates on repair or growth of injured cells.

Investigation on effect of Populus alba stands distance on density of pests and their natural enemies population under poplar/alfalfa agroforestry system.

PubMed

Khabir, Z H; Sadeghi, S E; Hanifeh, S; Eivazi, A

2009-01-15

This study was carried out in order to distinguish the effect of agroforestry system (combination of agriculture and forestry) on pests and natural enemy's population in poplar research station. Wood is one of the first substances that naturally was used for a long period of time. Forage is an important production of natural resources too. Some factors such as proper lands deficit, lack of economy, pest and disease attacks and faced production of these materials with serious challenges. Agroforestry is a method for decrease of the mentioned problems. The stands of poplar had have planted by complete randomized design with 4 treatments (stand distance) of poplar/alfalfa include 3x4, 3x6.7, 3x8, 3x10 m and 2 control treatments, alfalfa and poplar. The results showed that Chaitophorus populeti had the highest density in poplar and 3x10 m treatments. Monosteira unicostata is another insect pest that had most density in 3x10 m treatment. And alfalfa had high density of Chrysoperla carnea. The density of Coccinella septempunctata, were almost equal in all treatments.

THE ARECIBO LEGACY FAST ALFA SURVEY: THE GALAXY POPULATION DETECTED BY ALFALFA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Shan; Haynes, Martha P.; Giovanelli, Riccardo

Making use of H I 21 cm line measurements from the ALFALFA survey ({alpha}.40) and photometry from the Sloan Digital Sky Survey (SDSS) and Galaxy Evolution Explorer (GALEX), we investigate the global scaling relations and fundamental planes linking stars and gas for a sample of 9417 common galaxies: the {alpha}.40-SDSS-GALEX sample. In addition to their H I properties derived from the ALFALFA data set, stellar masses (M{sub *}) and star formation rates (SFRs) are derived from fitting the UV-optical spectral energy distributions. 96% of the {alpha}.40-SDSS-GALEX galaxies belong to the blue cloud, with the average gas fraction f{sub HI} {identical_to}more » M{sub HI}/M{sub *} {approx} 1.5. A transition in star formation (SF) properties is found whereby below M{sub *} {approx} 10{sup 9.5} M{sub Sun }, the slope of the star-forming sequence changes, the dispersion in the specific star formation rate (SSFR) distribution increases, and the star formation efficiency (SFE) mildly increases with M{sub *}. The evolutionary track in the SSFR-M{sub *} diagram, as well as that in the color-magnitude diagram, is linked to the H I content; below this transition mass, the SF is regulated strongly by the H I. Comparison of H I and optically selected samples over the same restricted volume shows that the H I-selected population is less evolved and has overall higher SFR and SSFR at a given stellar mass, but lower SFE and extinction, suggesting either that a bottleneck exists in the H I-to-H{sub 2} conversion or that the process of SF in the very H I-dominated galaxies obeys an unusual, low-efficiency SF law. A trend is found that, for a given stellar mass, high gas fraction galaxies reside preferentially in dark matter halos with high spin parameters. Because it represents a full census of H I-bearing galaxies at z {approx} 0, the scaling relations and fundamental planes derived for the ALFALFA population can be used to assess the H I detection rate by future blind H I surveys and

Effect of increasing the level of alfalfa hay in finishing beef heifer diets on intake, sorting, and feeding behavior.

PubMed

Madruga, A; González, L A; Mainau, E; Ruíz de la Torre, J L; Rodríguez-Prado, M; Manteca, X; Ferret, A

2018-02-15

Eight rumen cannulated Simmental heifers (BW = 281.4 ± 7.28 kg) were randomly assigned to one of four experimental treatments in a 4 × 4 replicated Latin square design to ascertain the effects of increasing levels of alfalfa hay on intake, sorting, and feeding behavior in comparison to barley straw as forage source. Treatments tested were four total mixed rations with: 1) 10% barley straw (10BS) with 7.0% NDF from forage, 2) 13% alfalfa hay (13AH) and less NDF from forage (5.7%) than 10BS, 3) 16% alfalfa hay (16AH) and the same NDF from forage (7.0%) as 10BS, and 4) 19% alfalfa hay (19AH) and more NDF from forage (8.3%) than 10BS. Each experimental period consisted of 3 wk for adaptation and 1 wk for sampling. Increasing the proportion of alfalfa hay in the diet linearly increased (P < 0.05) total DMI, CP intake, water consumption, intake of long, medium and fine particle size, extent of sorting of fine particle size, and time spent rumination, but linearly decreased (P < 0.05) extent of sorting of short particle size. Intake of DM was higher in heifers fed 16AH and 19AH than in heifers fed 10BS (P < 0.001). Intake of NDF and physically effective NDF (peNDF) was greater in 13AH, 16AH, and 19AH than in 10BS (P < 0.01). The DMI of medium and short particle size was greater in 13AH, 16AH, and 19AH than in 10BS (P < 0.05), whereas DMI of long particle size was greater in 16AH and 19AH compared to 10BS (P < 0.001). Heifers fed 13AH, 16AH, and 19AH diets sorted against fine particle size and sorted for or tended to sort for short, medium, and long particle sizes. Meal length was greater in heifers fed 16AH and 19AH than 10BS (P < 0.05). Time spent eating was not affected by diet but time spent ruminating was greater in heifers fed 19AH than in 10BS (P < 0.05). Results indicate that the inclusion of alfalfa hay at 19% of incorporation caused an increase in DM, NDF, and peNDF intake, in comparison to the 10BS diet. In the same way, intake of long, medium, and short

Comparison of stem morphology and anatomy of two alfalfa clonal lines exhibiting divergent cell wall composition

USDA-ARS?s Scientific Manuscript database

In previous research, two alfalfa clonal lines (252, 1283) were identified that exhibited environmentally stable differences in stem cell walls. Compared to stems of 1283, stems of 252 have a higher cell wall concentration and greater amounts of lignin and cellulose but reduced levels of pectic suga...

Meat goat kids finished on alfalfa, red clover, or orchardgrass pastures: Carcass merit and meat quality

USDA-ARS?s Scientific Manuscript database

This experiment was conducted in 2005-2007 to evaluate carcass and meat quality parameters when meat goat kids were finished on alfalfa (Medicago sativa L; ALF); red clover (Trifolium pretense L.; RCG); or orchardgrass (Dactylis glomerata L; OGR) pastures. Final shrunk body weights were similar whe...

Nutraceutical Potential of New Alfalfa (Medicago sativa) Ingredients for Beverage Preparations.

PubMed

Soto-Zarazúa, Maria Guadalupe; Bah, Moustapha; Costa, Anabela Silvia Gomes; Rodrigues, Francisca; Pimentel, Filipa Botelho; Rojas-Molina, Isela; Rojas, Alejandra; Oliveira, Maria Beatriz Prior Pinto

2017-10-01

Alfalfa (Medicago sativa) has been extensively used as animal feed, due to its fiber, protein, minerals, and vitamins, being also a useful source of phenolic compounds with potential therapeutic benefits. Nevertheless, its potential use as human ingredient is scarce. The aim of this work was to assess the nutritional composition, amino acid profile, and antioxidant capacity (AOC) of freeze-dried juice (FDJ) and fibrous residual material (RM), two new alfalfa-derived products (Adps) recently launched as ingredients for beverage preparations. Results demonstrated a high content of proteins (23-30 g/100 g FDJ and 13-17 g/100 g RM), crude fiber (29 g/100 g RM), and minerals (such as sodium, calcium, iron, and zinc). No significant difference was found in caloric content (4 kcal/g). Essential and nonessential amino acids were quantified in both Adps being leucine and lysine the most abundant. Total phenolic and total flavonoid contents (TPC and TFC, respectively) and their changes along the different harvesting periods of the year were also examined. FDJ presented the highest TPC in May (19 mg gallic acid equivalents/g dry weight [dw]), while in October TFC had the maximum value (4 mg catechin equivalents/g dw). Both products exhibited an interesting AOC by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power assays. This study reports the nutraceutical potential of two new types of Adps.

[Interactive effect of spent mushroom compost and rhamnolipids to enhance the efficiency of alfalfa remediation of aged PAHs contaminated soil].

PubMed

Zhang, Jing; Lin, Xian-Gui; Li, Xuan-Zhen; Yin, Rui

2010-10-01

Polycyclic aromatic hydrocarbons (PAHs) are a group of the most widespread organic pollutants, which distributed widely in soil and sediment. Pot experiment was conducted to improve efficiency of phytoremediation using alfalfa (Medicago sativa L.) in aged PAHs contaminated soil by introducing spent mushroom compost and rhamnolipids. Plant biomass, PAHs concentrations, number of soil microorganism, soil enzyme activity and soil microbial functional diversity were determined after 60 days of alfalfa growth. The results showed that within 60 days, removal ratio of PAHs in treatment of alfalfa alone (AL) reached to 14.43%, while removal ratio of PAHs in treatments of "GZ + RH0.5, + AL" and "GZ + RH1.0 + AL" reached to 32.64% and 36.95%, which were 115.45% and 156.06% higher than that of phytoremediation. Contrasted to the control, the treatment of "GZ + RH1.0 + AL" had more plant biomass than others, shoot and root dry weight were 1.05 g/pot and 0.20 g/pot, respectively. During the process of phytoremediation, the number of soil bacteria and fungi were greatly increased by "GZ + RH1.0 + AL" and reached to 31.37 x 10(6) CFU x g(-1) and 5.86 x 10(6) CFU x g(-1), especially the number of PAHs-degrading bacteria reached to 39.57 x 10(5) MPN x g(-1), which were 29 times more than control treatment and 4 times more than treatment of alfalfa alone (AL). Moreover, soil dehydrogenase activity and the functional diversity of soil microbial community were increased significantly by the treatment of "GZ + RH1.0 + AL", respectively. Therefore, interaction of spent mushroom compost and rhamnolipids to enhance the phytoremediation efficiency had satisfied results in removal aged PAHs from an agricultural soil, the feasibility of this method needed to be further proved by large-area scale field experiment.

Effects of animal type (wild vs. domestic) and diet alfalfa level on intake and digestibility of European adult rabbits (Oryctolagus cuniculus).

PubMed

Pinheiro, V; Outor-Monteiro, D; Mourão, J L; Cone, J W; Lourenço, A L

2018-02-01

The aim of this study was to evaluate the effect of the level of alfalfa in the diet on feed intake and digestibility of two types of rabbits, wild (Oryctolagus cuniculus algirus) vs. domestic (O. cuniculus cuniculus). Ten wild (W; mean LW = 927 g) and 10 domestic (D; mean LW = 4,645 g) adult rabbit does were fed ad libitum two pelleted diets: a control diet (C) with 15% of dehydrated alfalfa hay (as feed basis) and a test diet (A) with 36% of dehydrated alfalfa hay (as feed basis), according to a change-over design. Wild does dry matter (DM) intake per kg live weight (BW) was 55% higher (p < .001) than the intake of the D ones (58 g vs. 37 g DM per kg BW respectively). However, no difference (p > .05) was found when intake was expressed per kg 0.75 BW (ca. 56 g DM) and tended to be higher (p = .07) in D does when expressed per kg 0.67 BW (62 g vs. 55 g DM). Domestic does showed a higher (p < .05) DM, organic matter, crude energy and neutral detergent fibre digestibility (3; 2; 3; 3 percentage points respectively) than W does. The amount of nutrients and energy digested by D does was lower per kg BW (p < .001), similar per kg 0.75 BW (p > .05) and tended to be higher per kg 0.67 BW (p < .1) than in W does. The diet content of alfalfa did not affect (p > .05) the feed intake nor the diet digestibility. This study suggests that W rabbits exhibit a higher intake per kg BW and a lower digestibility than their D counterparts, which results in similar digestible nutrient and energy intake per kg BW powered to 0.75. The nutritive value of dehydrated alfalfa for rabbits, evaluated through intake and digestibility, seems to be equivalent to their base diets (forage plus concentrate). © 2017 Blackwell Verlag GmbH.

Growth of Salmonella on sprouting alfalfa seeds as affected by the inoculum size, native microbial load and Pseudomonas fluorescens 2-79.

PubMed

Liao, C-H

2008-02-01

To investigate the growth of salmonellae on sprouting alfalfa seeds as affected by the inoculum size, microbial load and Pseudomonas fluorescens 2-79. Alfalfa seeds pre-inoculated with < or =10(1)-10(3) CFU g(-1) of salmonellae and with or without Ps. fluorescens 2-79 were sprouted in glass jars and the population of salmonellae were determined daily for up to 6 days. The population of salmonellae on germinating seeds reached the maximum 2-3 days after sprouting when total bacterial count reached the maximum (10(9) CFU g(-1)). The population of salmonellae on sprouting seeds not treated with Ps. fluorescens 2-79 showed a net increase of 3-4 log units. However, the population of salmonellae on alfalfa seeds treated with Ps. fluorescens 2-79 showed a net increase of only 1-2 log units. Disinfection of seeds with calcium hypochlorite enhanced the growth of salmonellae. Treatment of seeds with Ps. fluorescens 2-79 reduced the growth of salmonellae by 2-3 log units. The potential of Ps. fluorescens 2-79 as a biological agent for use in control of salmonellae on sprouting seeds was demonstrated and warrants further investigation.

Interaction of Vesicular-Arbuscular Mycorrhizae and Cultivars of Alfalfa Susceptible and Resistant to Meloidogyne hapla.

PubMed

Grandison, G S; Cooper, K M

1986-04-01

The interaction between vesicular-arbuscular mycorrhizal (VAM) fungi and the root-knot nematode (Meloidogyne hapla) was investigated using both nematode-susceptible (Grasslands Wairau) and nematode-resistant (Nevada Synthetic XX) cultivars of alfalfa (Medicago sativa) at four levels of applied phosphate. Mycorrhizal inoculation improved plant growth and reduced nematode numbers and adult development in roots in dually infected cultures of the susceptible cultivar. The tolerance of plants to nematode infection and development when preinfected with mycorrhizal fungi was no greater than when they were inoculated with nematodes and mycorrhizal fungi simultaneously. Growth of plants of the resistant cultivar was unaffected by nematode inoculation but was improved by mycorrhizal inoculation. Numbers of nematode juveniles were lower in the roots of the resistant than of the susceptible cultivar and were further reduced by mycorrhizal inoculation, although no adult nematodes developed in any resistant cultivar treatment. Inoculation of alfalfa with VAM fungi increased the tolerance and resistance of a cultivar susceptible to M. hapla and improved the resistance of a resistant cultivar.

Detection of QTL for forage yield, lodging resistance and spring vigor traits in alfalfa (Medicago sativa L.)

USDA-ARS?s Scientific Manuscript database

Alfalfa (Medicago sativa L.) is an internationally significant forage crop. Forage yield, lodging resistance and spring vigor are important agronomic traits conditioned by quantitative genetic and environmental effects. The objective of this study was to identify quantitative trait loci (QTL) and mo...

Transcriptional profile of Salmonella enterica subsp. enterica serovar Weltevreden during alfalfa sprout colonization.

PubMed

Brankatschk, Kerstin; Kamber, Tim; Pothier, Joël F; Duffy, Brion; Smits, Theo H M

2014-11-01

Sprouted seeds represent a great risk for infection by human enteric pathogens because of favourable growth conditions for pathogens during their germination. The aim of this study was to identify mechanisms of interactions of Salmonella enterica subsp. enterica Weltevreden with alfalfa sprouts. RNA-seq analysis of S. Weltevreden grown with sprouts in comparison with M9-glucose medium showed that among a total of 4158 annotated coding sequences, 177 genes (4.3%) and 345 genes (8.3%) were transcribed at higher levels with sprouts and in minimal medium respectively. Genes that were higher transcribed with sprouts are coding for proteins involved in mechanisms known to be important for attachment, motility and biofilm formation. Besides gene expression required for phenotypic adaption, genes involved in sulphate acquisition were higher transcribed, suggesting that the surface on alfalfa sprouts may be poor in sulphate. Genes encoding structural and effector proteins of Salmonella pathogenicity island 2, involved in survival within macrophages during infection of animal tissue, were higher transcribed with sprouts possibly as a response to environmental conditions. This study provides insight on additional mechanisms that may be important for pathogen interactions with sprouts. © 2013 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

CO2 enrichment affects eco-physiological growth of maize and alfalfa under different water stress regimes in the UAE.

PubMed

Ksiksi, Taoufik Saleh; Ppoyil, Shaijal Babu Thru; Palakkott, Abdul Rasheed

2018-03-01

Water stress has been reported to alter morphology and physiology of plants affecting chlorophyll content, stomatal size and density. In this study, drought stress mitigating effects of CO 2 enrichment was assessed in greenhouse conditions in the hot climate of UAE. Commercially purchased maize ( Zea mays L.) and alfalfa ( Medicago sativa L.) were seeded in three different custom-built cage structures, inside a greenhouse. One cage was kept at 1000 ppm CO 2 , the second at 700 ppm CO 2 , and the third at ambient greenhouse CO 2 environment (i.e. 435 ppm). Three water stress treatments HWS (200 ml per week), MWS (400 ml per week), and CWS (600 ml per week) were given to each cage so that five maize pots and five alfalfa pots in each cage received same water stress treatments. In maize, total chlorophyll content was similar or higher in water stress treatments compared to control for all CO 2 concentrations. Stomatal lengths were higher in enriched CO 2 environments under water stress. At 700 ppm CO 2 , stomatal widths decreased as water stress increased from MWS to HWS. At both enriched CO 2 environments, stomatal densities decreased compared to ambient CO 2 environment. In alfalfa, there was no significant increase in total chlorophyll content under enriched CO 2 environments, even though a slight increase was noticed.

THE ALFALFA H α SURVEY. I. PROJECT DESCRIPTION AND THE LOCAL STAR FORMATION RATE DENSITY FROM THE FALL SAMPLE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sistine, Angela Van; Salzer, John J.; Janowiecki, Steven

2016-06-10

The ALFALFA H α survey utilizes a large sample of H i-selected galaxies from the ALFALFA survey to study star formation (SF) in the local universe. ALFALFA H α contains 1555 galaxies with distances between ∼20 and ∼100 Mpc. We have obtained continuum-subtracted narrowband H α images and broadband R images for each galaxy, creating one of the largest homogeneous sets of H α images ever assembled. Our procedures were designed to minimize the uncertainties related to the calculation of the local SF rate density (SFRD). The galaxy sample we constructed is as close to volume-limited as possible, is amore » robust statistical sample, and spans a wide range of galaxy environments. In this paper, we discuss the properties of our Fall sample of 565 galaxies, our procedure for deriving individual galaxy SF rates, and our method for calculating the local SFRD. We present a preliminary value of log(SFRD[ M {sub ⊙} yr{sup −1} Mpc{sup −3}]) = −1.747 ± 0.018 (random) ±0.05 (systematic) based on the 565 galaxies in our Fall sub-sample. Compared to the weighted average of SFRD values around z ≈ 2, our local value indicates a drop in the global SFRD of a factor of 10.2 over that lookback time.« less

Comparative proteomic analysis of alfalfa revealed new salt and drought stress-related factors involved in seed germination.

PubMed

Ma, Qiaoli; Kang, Junmei; Long, Ruicai; Zhang, Tiejun; Xiong, Junbo; Zhang, Kun; Wang, Tenghua; Yang, Qingchuan; Sun, Yan

2017-07-01

Salinity and drought are two major environmental factors that limit the growth and yield of many forage crops in semi-arid and arid regions. Alfalfa (Medicago sativa L.) is one of the most important forage crops in many countries. We aim to investigate the molecular mechanisms of alfalfa in response to salt and drought stresses in this study. Physiological and proteomic analyses were applied to examine the Zhongmu NO.3 alfalfa seed germination stage with 200 mM NaCl and 180 g·L -1 polyethylene glycol (PEG) treatments. The germination ability of the seed and the accumulation of osmotic solutes were quite different between the NaCl and PEG treatments. More than 800 protein spots were detected by proteomics technology on two-dimensional electrophoresis (2-DE) gels. The abundance of twenty-eight proteins were decreased or increased after salt and drought stress. Seventeen of these proteins were identified and classified into six functional categories through mass spectrometry (MS). The six groups involved in salt- and PEG-mediated stress included defense response, energy metabolism, protein synthesis and degradation, oxidative stress, carbohydrate metabolism-associated proteins, and unknown proteins. We discovered that some proteins related to carbohydrate metabolism and energy production increased in abundance under salt- and PEG-mediated drought stress. This demonstrates a common mechanism of energy consumption during abiotic stresses. Further study of these proteins with unknown function will provide insights into the molecular mechanisms of abiotic stress and the discovery of new candidate markers.

Identification of transcriptome involved in atrazine detoxification and degradation in alfalfa (Medicago sativa) exposed to realistic environmental contamination.

PubMed

Zhang, Jing Jing; Lu, Yi Chen; Zhang, Shu Hao; Lu, Feng Fan; Yang, Hong

2016-08-01

Plants are constantly exposed to a variety of toxic compounds (or xenobiotics) such as pesticides (or herbicides). Atrazine (ATZ) as herbicide has become one of the environmental contaminants due to its intensive use during crop production. Plants have evolved strategies to cope with the adverse impact of ATZ. However, the mechanism for ATZ degradation and detoxification in plants is largely unknown. Here we employed a global RNA-sequencing (RNA-Seq) strategy to dissect transcriptome variation in alfalfa (Medicago sativa) exposed to ATZ. Four libraries were constructed including Root-ATZ (root control, ATZ-free), Shoot-ATZ, Root+ATZ (root treated with ATZ) and Shoot+ATZ. Hierarchical clustering was performed to display the expression patterns for all differentially expressed genes (DEGs) under ATZ exposure. Transcripts involved in ATZ detoxification, stress responses (e.g. oxidation and reduction, conjugation and hydrolytic reactions), and regulations of cysteine biosynthesis were identified. Several genes encoding glycosyltransferases, glutathione S-transferases or ABC transporters were up-regulated notably. Also, many other genes involved in oxidation-reduction, conjugation, and hydrolysis for herbicide degradation were differentially expressed. These results suggest that ATZ in alfalfa can be detoxified or degraded through different pathways. The expression patterns of some DEGs by high-throughput sequencing were well confirmed by qRT-PCR. Our results not only highlight the transcriptional complexity in alfalfa exposed to ATZ but represent a major improvement for analyzing transcriptional changes on a large scale as well. Copyright © 2016 Elsevier Inc. All rights reserved.

Physiological and Proteomic Responses of Contrasting Alfalfa (Medicago sativa L.) Varieties to PEG-Induced Osmotic Stress.

PubMed

Zhang, Cuimei; Shi, Shangli

2018-01-01

Drought severely limits global plant distribution and agricultural production. Elucidating the physiological and molecular mechanisms governing alfalfa stress responses will contribute to the improvement of drought tolerance in leguminous crops. In this study, the physiological and proteomic responses of two alfalfa ( Medicago sativa L.) varieties contrasting in drought tolerance, Longzhong (drought-tolerant) and Gannong No. 3 (drought-sensitive), were comparatively assayed when seedlings were exposed to -1.2 MPa polyethylene glycol (PEG-6000) treatments for 15 days. The results showed that the levels of proline, malondialdehyde (MDA), hydrogen peroxide (H 2 O 2 ), hydroxyl free radical (OH • ) and superoxide anion free radical (O 2 •- ) in both varieties were significantly increased, while the root activity, the superoxide dismutase (SOD) and glutathione reductase (GR) activities, and the ratios of reduced/oxidized ascorbate (AsA/DHA) and reduced/oxidized glutathione (GSH/GSSG) were significantly decreased. The soluble protein and soluble sugar contents, the total antioxidant capability (T-AOC) and the activities of peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) first increased and then decreased with the increase in treatment days. Under osmotic stress, Longzhong exhibited lower levels of MDA, H 2 O 2 , OH • and O 2 •- but higher levels of SOD, CAT, APX, T-AOC and ratios of AsA/DHA and GSH/GSSG compared with Gannong No.3. Using isobaric tags for relative and absolute quantification (iTRAQ), 142 differentially accumulated proteins (DAPs) were identified from two alfalfa varieties, including 52 proteins (34 up-regulated and 18 down-regulated) in Longzhong, 71 proteins (28 up-regulated and 43 down-regulated) in Gannong No. 3, and 19 proteins (13 up-regulated and 6 down-regulated) shared by both varieties. Most of these DAPs were involved in stress and defense, protein metabolism, transmembrane transport, signal transduction, as well as cell

Physiological and Proteomic Responses of Contrasting Alfalfa (Medicago sativa L.) Varieties to PEG-Induced Osmotic Stress

PubMed Central

Zhang, Cuimei; Shi, Shangli

2018-01-01

Drought severely limits global plant distribution and agricultural production. Elucidating the physiological and molecular mechanisms governing alfalfa stress responses will contribute to the improvement of drought tolerance in leguminous crops. In this study, the physiological and proteomic responses of two alfalfa (Medicago sativa L.) varieties contrasting in drought tolerance, Longzhong (drought-tolerant) and Gannong No. 3 (drought-sensitive), were comparatively assayed when seedlings were exposed to -1.2 MPa polyethylene glycol (PEG-6000) treatments for 15 days. The results showed that the levels of proline, malondialdehyde (MDA), hydrogen peroxide (H2O2), hydroxyl free radical (OH•) and superoxide anion free radical (O2•-) in both varieties were significantly increased, while the root activity, the superoxide dismutase (SOD) and glutathione reductase (GR) activities, and the ratios of reduced/oxidized ascorbate (AsA/DHA) and reduced/oxidized glutathione (GSH/GSSG) were significantly decreased. The soluble protein and soluble sugar contents, the total antioxidant capability (T-AOC) and the activities of peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) first increased and then decreased with the increase in treatment days. Under osmotic stress, Longzhong exhibited lower levels of MDA, H2O2, OH• and O2•- but higher levels of SOD, CAT, APX, T-AOC and ratios of AsA/DHA and GSH/GSSG compared with Gannong No.3. Using isobaric tags for relative and absolute quantification (iTRAQ), 142 differentially accumulated proteins (DAPs) were identified from two alfalfa varieties, including 52 proteins (34 up-regulated and 18 down-regulated) in Longzhong, 71 proteins (28 up-regulated and 43 down-regulated) in Gannong No. 3, and 19 proteins (13 up-regulated and 6 down-regulated) shared by both varieties. Most of these DAPs were involved in stress and defense, protein metabolism, transmembrane transport, signal transduction, as well as cell wall and

Evaluation of alfalfa leaf meal for dairy cows. Quarterly report, July 1, 1997--September 30, 1997

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akayezu, J.M.; Jorgensen, M.A.; Linn, J.G.

1997-10-30

A series of laboratory tests and two feeding experiments were conducted to determine the quality and evaluate the feeding value of alfalfa leaf meal (ALM) for dairy cows. An experiment was also conducted to enhance the protein value of ALM for ruminants. The fiber content of 6 different samples obtained from the processing plant from November 1996 to August 1997 were variable, ranging from 28.8 to 44.5% of DM for NDF, and from 16.0 to 28.6% of DM for ADF. Ash content ranged from 10.1 to 13.8% of the DM. The protein content of ALM was fairly constant and rangedmore » from 21.8 to 23.6% of DM. Amino acids comprise at least 70% of the total CP in ALM, but essential amino acids comprise only about 35% of the total CP. The amino acid profile of ALM is similar to that of alfalfa hay, but markedly different from that of soybean meal. Overall, ALM produced to date is similar in nutrient content to prime alfalfa hay. In one of the feeding trials, ALM pellets were used to replace part of the hay in diets for early lactation cows. The results indicate that ALM pellets can make up as much as 16% of the diet DM in replacement of an equivalent amount of high quality chopped alfalfa hay without adverse effects on production or rumen health. In an other study, ALM replaced soybean meal to supply up to 3 3 % of the total CP in the diet without any detrimental effect on production. However, in each study, dry matter intake was reduced when ALM was included in the diet at or above 15 to 16% of the DM. Although this reduction in feed intake did not influence milk production over the short duration of these studies, it is not known what would happen if ALM was fed over long periods of time. Also, these results should not be interpreted to suggest either that ALM may used to replace all the hay in the diets or that ALM in meal form may be used to replace hay in the diets. Moreover, feed consumption by cows used in these experiments was rather high and somewhat atypical of most cows.« less

Fermentation of alfalfa wet-fractionation liquids to volatile fatty acids by Streptococcus bovis and Megasphaera elsdenii

USDA-ARS?s Scientific Manuscript database

A “green juice”, obtained by squeezing freshly harvested alfalfa leaves amended with a commercial lactic acid bacterial inoculant, was readily fermented by 7- to 21-d incubation at room temperature to obtain lactic acid at concentrations of 12-46 g l-1, along with additional acetic and succinic acid...

Spissistilus festinus reovirus: a novel, unassigned species of the family Reoviridae infecting the three-cornered alfalfa hopper

USDA-ARS?s Scientific Manuscript database

A complex set of double stranded RNAs (dsRNA) were isolated from threecornered alfalfa hopper (Spissistilus festinus), a plant-feeding hemipteran insect pest. A subset of these dsRNAs constitute the genome of a novel, unassigned reovirus designated as Spissistilus festinus reovirus (SpFRV). Phylogen...

Distribution of glassy-winged sharpshooter and threecornered alfalfa hopper on plant hosts in the San Joaquin valley

USDA-ARS?s Scientific Manuscript database

Homalodisca vitripennis Germar and Spissistilus festinus Say populations were surveyed bimonthly for 14 months in Kern County at five agricultural sites made up of a variety of potential host plants. Additionally, S. festinus populations were surveyed in four alfalfa fields in Kern and Tulare Counti...

Alfalfa endophytes as novel sources of antimicrobial compounds that inhibit the growth of human and plant pathogens

USDA-ARS?s Scientific Manuscript database

Fungal endophytes may contribute to plant health and disease protection, yet little is known about their various roles in alfalfa. Also, endophytes from several plant species produce novel antimicrobial compounds that may be useful clinically. We isolated endophytic fungi from over 50 samples from s...

The Undergraduate ALFALFA Team: A Model for Involving Undergraduates in Major Legacy Astronomy Research

NASA Astrophysics Data System (ADS)

Troischt, Parker; Koopmann, Rebecca A.; Haynes, Martha P.; Higdon, Sarah; Balonek, Thomas J.; Cannon, John M.; Coble, Kimberly A.; Craig, David; Durbala, Adriana; Finn, Rose; Hoffman, G. Lyle; Kornreich, David A.; Lebron, Mayra E.; Crone-Odekon, Mary; O'Donoghue, Aileen A.; Olowin, Ronald Paul; Pantoja, Carmen; Rosenberg, Jessica L.; Venkatesan, Aparna; Wilcots, Eric M.; Alfalfa Team

2015-01-01

The NSF-sponsored Undergraduate ALFALFA (Arecibo Legacy Fast ALFA) Team (UAT) is a consortium of 19 institutions founded to promote undergraduate research and faculty development within the extragalactic ALFALFA HI blind survey project and follow-up programs. The collaborative nature of the UAT allows faculty and students from a wide ​range of public and private colleges and especially those with small astronomy programs to develop scholarly collaborations. Components of the program include an annual undergraduate workshop at Arecibo Observatory, observing runs at Arecibo, computer infrastructure, summer and academic year research projects, and dissemination at national meetings (e.g., Alfvin et al., Martens et al., Sanders et al., this meeting). Through this model, faculty and students are learning how science is accomplished in a large collaboration while contributing to the scientific goals of a major legacy survey. In the 7 years of the program, 23 faculty and more than 220 undergraduate students have participated at a significant level. 40% of them have been women and members of underrepresented groups. Faculty, many of whom were new to the collaboration and had expertise in other fields, contribute their diverse sets of skills to ALFALFA ​related projects via observing, data reduction, collaborative research, and research with students. 142 undergraduate students have attended the annual workshops at Arecibo Observatory, interacting with faculty, graduate students, their peers, and Arecibo staff in lectures, group activities, tours, and observing runs. Team faculty have supervised 131 summer research projects and 94 academic year (e.g., senior thesis) projects. 62 students have traveled to Arecibo Observatory for observing runs and 46 have presented their results at national meetings. 93% of alumni are attending graduate school and/or pursuing a career in STEM. Half of those pursuing graduate degrees in Physics or Astronomy are women. This work has been

Genetic Diversity and Phenotypic Variation for Drought Resistance in Alfalfa (Medicago sativa L.) Germplasm Collected for Drought Tolerance

USDA-ARS?s Scientific Manuscript database

Drought is a major environmental factor hampering alfalfa productivity worldwide. Gene banks provide an array of trait diversity, frequently consisting of specific seed collection projects that focused on acquiring germplasm adapted to specific traits such as drought tolerance. These subsets provide...

Temperature stress affects the expression of immune response genes in the alfalfa leafcutting bee (Megachile rotundata)

USDA-ARS?s Scientific Manuscript database

The alfalfa leafcutting bee (Megachile rotundata) is affected by a fungal disease called chalkbrood. In several species of bees, chalkbrood is more likely to occur in larvae kept at 25-30 C than at 35 C. We found that both high and low temperature stress increased the expression of immune response g...

U.S. Marine Corps Study of Establishing Time Criteria for Logistics Tasks

DTIC Science & Technology

2004-09-30

STATISTICS FOR REQUESTS PER DAY FOR TWO BATTALIONS II-25 II-6 SUMMARY STATISTICS IN HOURS FOR RESOURCE REQUIREMENTS PER DAY FOR TWO BATTALIONS II-26 II-7...SUMMARY STATISTICS FOR INDIVIDUALS FOR RESOURCE REQUIREMENTS PER DAY FOR TWO BATTALIONS II-27 Study of Establishing Time Criteria for Logistics...developed and run to provide statistical information for analysis. In Task Four, the study team used Task Three findings to determine data requirements

Replacing alfalfa silage with tannin-containing birdsfoot trefoil silage in total mixed rations for lactating dairy cows

USDA-ARS?s Scientific Manuscript database

Two lactation trials were conducted to assess the feeding value of silage made from populations of birdsfoot trefoil (BFT, Lotus corniculatus L.) that had been selected for low (BFTL), medium (BFTM), and high (BFTH) levels of condensed tannins (CT). These silages were compared to an alfalfa silage (...

Changes in ruminal bacterial community composition following feeding of alfalfa silage inoculated with a commercial silage inoculant

USDA-ARS?s Scientific Manuscript database

Some silage inoculants promote an increase in milk production, possibly through altering the rumen microflora. In this study, dairy cows fed alfalfa silage treated with the inoculant, Lactobacillus plantarum MTD/1 (LPS), were compared to cows fed untreated silage (Ctrl) with the objectives: 1) to de...

Changes in respiratory structure and function during post-diapause development in the alfalfa leafcutting bee, Megachile rotundata

USDA-ARS?s Scientific Manuscript database

Megachile rotundata, the alfalfa leafcutting bee, is a solitary, cavity-nesting bee. M. rotundata develop from eggs laid inside brood cells constructed from leaf pieces and placed in series in an existing cavity. Due to the cavity nesting behavior of M. rotundata, developing bees may experience hyp...

The effect of post-diapause development on respiratory function in the alfalfa leaf-cutting bee, Megachile rotundata

USDA-ARS?s Scientific Manuscript database

Megachile rotundata, the alfalfa leaf-cutting bee, is a solitary, cavity-nesting bee. M. rotundata develop inside brood cells constructed from leaf pieces and sealed with the female’s saliva. During development, M. rotundata may experience hypoxic conditions from the cavity in which they reside; oxy...

Alfalfa Intervention Alters Rumen Microbial Community Development in Hu Lambs During Early Life.

PubMed

Yang, Bin; Le, Jiaqing; Wu, Peng; Liu, Jianxin; Guan, Le L; Wang, Jiakun

2018-01-01

The pre-weaning period is crucial for rumen developmental plasticity, which can have a long-term impact on animal performance. Understanding the rumen microbiota during early life is important to elucidate its potential role in rumen development. In this study, the rumen microbiota of 10-day-old Hu lambs fed either milk replacer (B-10), milk replacer and starter (STA) or milk replacer and starter supplemented with alfalfa (S-ALF) in the pre- (d17, 24, and 38) and post-weaning periods (d45 and 66) were assessed to characterize rumen microbial colonization during early life and its response to fiber intervention. In the rumens of B-10 lambs, 498 operational taxonomic units belonging to 33 predominant genera were observed, and the top six predicted functions included "Membrane transport," "carbohydrate metabolism," "amino acid metabolism," "replication and repair," "translation," and "energy metabolism." Prevotella , Succinivibrio , Bifidobacterium , and Butyrivibrio abundances were increased at d38 for both STA and S-ALF groups compared to the B-10 group, whereas fibrolytic bacteria of the taxa Lachnospiraceae and Treponema were only increased in the S-ALF group at d38. A number of saccharolytic bacteria ( Bacteroidaceae ), organic acid-producing bacteria ( Coprococcus and Actinomyces ), proteolytic and amino acid fermenters ( Fusobacterium ) and fibrolytic bacteria (unclassified Ruminococcaceae ) were significantly decreased in the STA lambs but not in the S-ALF lambs at d38. After weaning and exposed to alfalfa, the rumen microbial composition in the STA group started to appear similar to that of the S-ALF lambs. The relative abundance of unclassified Clostridiales was higher in S-ALF lambs than STA lambs after weaning. Spearman's correlation analysis showed positive relationships between unclassified Lachnospiraceae , unclassified Clostridiales , Treponema , unclassified Bacteroidales , Coprococcus and crude protein intake, neutral detergent fiber intake, and

Effects of cyanobacterial toxins and cyanobacterial cell-free crude extract on germination of alfalfa (Medicago sativa) and induction of oxidative stress.

PubMed

Pflugmacher, Stephan; Jung, Katharina; Lundvall, Linn; Neumann, Stefanie; Peuthert, Anja

2006-09-01

Cyanobacterial toxins have adverse effects on both terrestrial and aquatic plants. Microcystins are cyclic heptapeptides and an important group of cyanotoxins. When lake water contaminated with cyanobacterial blooms is used for spray irrigation, these toxins can come in contact with agricultural plants. During the exposure to these toxins, reactive oxygen species can form. These reactive oxygen species have a strong reactivity and are able to interact with other cellular compounds (lipids, protein, and DNA). Plants have antioxidative systems that will limit the negative effects caused by reactive oxygen species. These systems consist of enzymes, such as superoxide dismutase, catalase, and ascorbate peroxidase, and nonenzymatic substances, such as reduced glutathione or vitamins. The aim of the present study was to investigate the effects of cyanobacterial toxins (microcystins and anatoxin-a) and cyanobacterial cell-free crude extract on alfalfa (Medicago sativa) seedlings. Inhibition of germination and root growth was observed with toxin concentrations of 5.0 microg/L. Also, oxidative damage, such as lipid peroxidation, was detected after the exposure of alfalfa seedlings to the toxin. Reactive oxygen detoxifying enzymes were elevated, showing a marked response in alfalfa to oxidative stress caused by the exposure to cyanobacterial metabolites that might influence the growth and development of these plants negatively.

Effect of supplementation with linseed or a blend of aromatic spices and time on feed on fatty acid composition, meat quality and consumer liking of meat from lambs fed dehydrated alfalfa or corn.

PubMed

Realini, C E; Bianchi, G; Bentancur, O; Garibotto, G

2017-05-01

Cross-bred lambs (n=72) were fed finishing diets using a factorial arrangement of treatments: BASAL DIET (alfalfa pellets or corn), SUPPLEMENT (none, linseed or aromatic spices), TIME ON FEED (41 or 83days). Carcass and meat quality traits, fatty acid composition, color stability and consumer liking were determined. Feeding alfalfa improved sensory ratings and fatty acid composition of lamb. However, corn or longer alfalfa feeding would be recommended if heavier and fatter carcasses are sought. Consumer liking and fatty acid composition of lamb were improved with addition of spices and linseed, respectively. But additional antioxidant strategies should be considered to delay meat color deterioration during storage if lambs are fed corn-linseed for 83days. Although alfalfa basal diet and linseed supplementation improved fatty acid composition, feeding the basal diets for at least 41days resulted in low n-3 fatty acid concentrations in muscle. Copyright © 2017 Elsevier Ltd. All rights reserved.

ECOLOGICAL RISK ASSESSMENT OF ALFALFA (MEDICAGO VARIA L.) GENETICLALY ENGINEERED TO EXPRESS A HUMAN METALLOTHIONEIN (HMT) GENE

EPA Science Inventory

The objectives of these studies were two-fold: (1) to determine efficacy of low and high expression hMT gene constructs by assessing accumulation of Cu in shoots of parental and transgenic plants of alfalfa (Medicago varia L.) exposed to different concentrations of CuSO4 by addit...

Detoxification of Atrazine by Low Molecular Weight Thiols in Alfalfa (Medicago sativa).

PubMed

Zhang, Jing Jing; Xu, Jiang Yan; Lu, Feng Fan; Jin, She Feng; Yang, Hong

2017-10-16

Low molecular weight (LMW) thiols in higher plants are a group of sulfur-rich nonprotein compounds and play primary and multiple roles in cellular redox homeostasis, enzyme activities, and xenobiotics detoxification. This study focused on identifying thiols-related protein genes from the legume alfalfa exposed to the herbicide atrazine (ATZ) residues in environment. Using high-throughput RNA-sequencing, a set of ATZ-responsive thiols-related protein genes highly up-regulated and differentially expressed in alfalfa was identified. Most of the differentially expressed genes (DEGs) were involved in regulation of biotic and abiotic stress responses. By analyzing the genes involved in thiols-mediated redox homeostasis, we found that many of them were thiols-synthetic enzymes such as γ-glutamylcysteine synthase (γECS), homoglutathione synthetase (hGSHS), and glutathione synthetase (GSHS). Using liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS), we further characterized a group of ATZ-thiols conjugates, which are the detoxified forms of ATZ in plants. Cysteine S-conjugate ATZ-HCl+Cys was the most important metabolite detected by MS. Several other ATZ-conjugates were also examined as ATZ-detoxified metabolites. Such results were validated by characterizing their analogs in rice. Our data showed that some conjugates under ATZ stress were detected in both plants, indicating that some detoxified mechanisms and pathways can be shared by the two plant species. Overall, these results indicate that LMW thiols play critical roles in detoxification of ATZ in the plants.

Alfalfa Cellulose Synthase Gene Expression under Abiotic Stress: A Hitchhiker’s Guide to RT-qPCR Normalization

PubMed Central

Guerriero, Gea; Legay, Sylvain; Hausman, Jean-Francois

2014-01-01

Abiotic stress represents a serious threat affecting both plant fitness and productivity. One of the promptest responses that plants trigger following abiotic stress is the differential expression of key genes, which enable to face the adverse conditions. It is accepted and shown that the cell wall senses and broadcasts the stress signal to the interior of the cell, by triggering a cascade of reactions leading to resistance. Therefore the study of wall-related genes is particularly relevant to understand the metabolic remodeling triggered by plants in response to exogenous stresses. Despite the agricultural and economical relevance of alfalfa (Medicago sativa L.), no study, to our knowledge, has addressed specifically the wall-related gene expression changes in response to exogenous stresses in this important crop, by monitoring the dynamics of wall biosynthetic gene expression. We here identify and analyze the expression profiles of nine cellulose synthases, together with other wall-related genes, in stems of alfalfa plants subjected to different abiotic stresses (cold, heat, salt stress) at various time points (e.g. 0, 24, 72 and 96 h). We identify 2 main responses for specific groups of genes, i.e. a salt/heat-induced and a cold/heat-repressed group of genes. Prior to this analysis we identified appropriate reference genes for expression analyses in alfalfa, by evaluating the stability of 10 candidates across different tissues (namely leaves, stems, roots), under the different abiotic stresses and time points chosen. The results obtained confirm an active role played by the cell wall in response to exogenous stimuli and constitute a step forward in delineating the complex pathways regulating the response of plants to abiotic stresses. PMID:25084115

Plant-Microbe and Abiotic Factors Influencing Salmonella Survival and Growth on Alfalfa Sprouts and Swiss Chard Microgreens

PubMed Central

Reed, Elizabeth; Ferreira, Christina M.; Bell, Rebecca; Brown, Eric W.

2018-01-01

ABSTRACT Microgreens, like sprouts, are relatively fast-growing products and are generally consumed raw. Moreover, as observed for sprouts, microbial contamination from preharvest sources may also be present in the production of microgreens. In this study, two Salmonella enterica serovars (Hartford and Cubana), applied at multiple inoculation levels, were evaluated for survival and growth on alfalfa sprouts and Swiss chard microgreens by using the most-probable-number (MPN) method. Various abiotic factors were also examined for their effects on Salmonella survival and growth on sprouts and microgreens. Community-level physiological profiles (CLPPs) of sprout/microgreen rhizospheres with different levels of S. enterica inoculation at different growth stages were characterized by use of Biolog EcoPlates. In the seed contamination group, the ability of S. enterica to grow on sprouting alfalfa seeds was affected by both seed storage time and inoculation level but not by serovar. However, the growth of S. enterica on Swiss chard microgreens was affected by serovar and inoculation level. Seed storage time had little effect on the average level of Salmonella populations in microgreens. In the irrigation water contamination group, the growth of Salmonella on both alfalfa sprouts and microgreens was largely affected by inoculation level. Surprisingly, the growth medium was found to play an important role in Salmonella survival and growth on microgreens. CLPP analysis showed significant changes in the microbial community metabolic diversity during sprouting for alfalfa sprouts, but few temporal changes were seen with microgreens. The data suggest that the change in rhizosphere bacterial functional diversity was dependent on the host but independent of Salmonella contamination. IMPORTANCE Sprouts and microgreens are considered “functional foods,” i.e., foods containing health-promoting or disease-preventing properties in addition to normal nutritional values. However, the

Plant-Microbe and Abiotic Factors Influencing Salmonella Survival and Growth on Alfalfa Sprouts and Swiss Chard Microgreens.

PubMed

Reed, Elizabeth; Ferreira, Christina M; Bell, Rebecca; Brown, Eric W; Zheng, Jie

2018-05-01

Microgreens, like sprouts, are relatively fast-growing products and are generally consumed raw. Moreover, as observed for sprouts, microbial contamination from preharvest sources may also be present in the production of microgreens. In this study, two Salmonella enterica serovars (Hartford and Cubana), applied at multiple inoculation levels, were evaluated for survival and growth on alfalfa sprouts and Swiss chard microgreens by using the most-probable-number (MPN) method. Various abiotic factors were also examined for their effects on Salmonella survival and growth on sprouts and microgreens. Community-level physiological profiles (CLPPs) of sprout/microgreen rhizospheres with different levels of S. enterica inoculation at different growth stages were characterized by use of Biolog EcoPlates. In the seed contamination group, the ability of S. enterica to grow on sprouting alfalfa seeds was affected by both seed storage time and inoculation level but not by serovar. However, the growth of S. enterica on Swiss chard microgreens was affected by serovar and inoculation level. Seed storage time had little effect on the average level of Salmonella populations in microgreens. In the irrigation water contamination group, the growth of Salmonella on both alfalfa sprouts and microgreens was largely affected by inoculation level. Surprisingly, the growth medium was found to play an important role in Salmonella survival and growth on microgreens. CLPP analysis showed significant changes in the microbial community metabolic diversity during sprouting for alfalfa sprouts, but few temporal changes were seen with microgreens. The data suggest that the change in rhizosphere bacterial functional diversity was dependent on the host but independent of Salmonella contamination. IMPORTANCE Sprouts and microgreens are considered "functional foods," i.e., foods containing health-promoting or disease-preventing properties in addition to normal nutritional values. However, the microbial

Do soil tests help forecast nitrogen response in first-year corn following alfalfa on fine-textured soils?

USDA-ARS?s Scientific Manuscript database

Improved methods of predicting grain yield response to fertilizer N for first-year corn (Zea mays L.) following alfalfa (Medicago sativa L.) on fine-textured soils are needed. Data from 21 site-years in the North Central Region were used to (i) determine how Illinois soil nitrogen test (ISNT) and pr...

Investigations conducted by Department of Agriculture Research of the American Smelting and Refining Company, concerning the feeding quality of alfalfa injured by sulfur dioxide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cunningham, O.C.; Addington, L.H.

1937-01-01

Alfalfa which was produced in the proximity of a smelting company was fed to dairy cows and the results compared to dairy cows fed a matched crop which was grown many miles away. The fumigated alfalfa had 20% or more of the leaflets that were affected. The feeding experiment lasted 90 days with milk and butter fat production carefully determined and a sulfur analysis was made of each hay. Results indicate that there were no significant difference in milk or in butter fat production, nor in the weight of the cows in favor of either ration.

Genomic Architecture and Phenotypic Plasticity of Forage Quality in Response to Water Deficit in Alfalfa (Medicago sativa L.)

USDA-ARS?s Scientific Manuscript database

A panel of alfalfa cultivars and landraces originated worldwide with potential value of drought tolerance were selected from USDA-Western Region Plant Germplasm Center. Field trials were conducted in the in Roza farm in Prosser, WA and a gradient of water deficits were applied. Aboveground biomass w...

Voluntary intake and digestibility by sheep of alfalfa ensiled at different moisture concentrations following fertilization with dairy slurry

USDA-ARS?s Scientific Manuscript database

Dairy slurry is used commonly as an animal-sourced fertilizer in agronomic production. However, residual effects of slurry application on intake and digestibility of alfalfa (Medicago sativa L.) silage from subsequent harvests are not well known. The objective of this study was to determine if mois...

Solar Energy Task Force Report: Technical Training Guidelines.

ERIC Educational Resources Information Center

O'Connor, Kevin

This task force report offers guidelines and information for the development of vocational education programs oriented to the commercial application of solar energy in water and space heating. After Section I introduces the Solar Energy Task Force and its activities, Section II outlines the task force's objectives and raises several issues and…

Individual and combined application of dry heat with high hydrostatic pressure to inactivate Salmonella and Escherichia coli O157:H7 on alfalfa seeds.

PubMed

Neetoo, Hudaa; Chen, Haiqiang

2011-02-01

Alfalfa sprouts are recurrently implicated in outbreaks of food-borne illnesses as a result of contamination with Salmonella or Escherichia coli O157:H7. In the majority of these outbreaks, the seeds themselves have been shown to be the most likely source of contamination. The aims of this study were to comparatively assess the efficacy of dry heat treatments alone or in conjunction with high hydrostatic pressure (HHP) to eliminate a ∼5 log CFU/g load of Salmonella and E. coli O157:H7 on alfalfa seeds. Dry heat treatments at mild temperatures of 55 and 60 °C achieved ≤1.6 and 2.2 log CFU/g reduction in the population of Salmonella spp. after a 10-d treatment, respectively. However, subjecting alfalfa seeds to more aggressive temperatures of 65 °C for 10 days or 70 °C for 24 h eliminated a ∼5 log population of Salmonella and E. coli O157:H7. We subsequently showed that the sequential application of dry heating followed by HHP could substantially reduce the dry heating exposure time while achieving equivalent decontamination results. Dry heating at 55, 60, 65 and 70 °C for 96, 24, 12 and 6 h, respectively followed by a pressure treatment of 600 MPa for 2 min at 35 °C were able to eliminate a ∼5 log CFU/g initial population of both pathogens. Finally, we evaluated the impact of selected treatments on the seed germination percentages and yield ratios and showed that dry heating at 65 °C for 10 days did not bring about any considerable decrease in the germination percentage. However, the sprout yield of treated alfalfa seeds was reduced by 21%. Dry heating at 60 and 65 °C for 24 and 12 h respectively followed by the pressure treatment of 600 MPa for 2 min at 35 °C did not significantly (P > 0.05) affect the germination percentage of alfalfa seeds although a reduction in the sprouting yield was observed. Copyright © 2010 Elsevier Ltd. All rights reserved.

Supplementing rumen-protected Met and Lys in alfalfa and red clover silage diets fed to lactating dairy cows

USDA-ARS?s Scientific Manuscript database

The action of polyphenol oxidase reduces NPN formation in red clover silage (RCS). In seven previous trials, RCS averaged (% of total N) 36% NPN vs. 54% NPN in alfalfa silage (AS). Feeding RCS has been found to increase intestinal protein absorption but with no improvement in N utilization, suggesti...

Resistant and susceptible responses in alfalfa (Medicago sativa) to bacterial stem blight caused by Pseudomonas syringae pv. syringae

USDA-ARS?s Scientific Manuscript database

Bacterial stem blight caused by Pseudomonas syringae pv. syringae is a common disease of alfalfa (Medicago sativa L.) in the central and western U.S. and has been reported in Australia and Europe. The disease is not always recognized because symptoms are often associated with frost damage. Two culti...

Cloning and expression of 1-aminocyclopropane-1-carboxylate oxidase cDNA induced by thidiazuron during somatic embryogenesis of alfalfa (Medicago sativa).

PubMed

Feng, Bi-Hong; Wu, Bei; Zhang, Chun-Rong; Huang, Xia; Chen, Yun-Feng; Huang, Xue-Lin

2012-01-15

Embryogenic callus (EC) induced from petioles of alfalfa (Medicago sativa L. cv. Jinnan) on B5h medium turned green, compact and non-embryogenic when the kinetin (KN) in the medium was replaced partially or completely by thidiazuron (TDZ). The application of CoCl₂, which is an inhibitor of 1-aminocyclopropane-1-carboxylate oxidase (ACO), counteracted the effect of TDZ. Ethylene has been shown to be involved in the modulation of TDZ-induced morphogenesis responses. However, very little is known about the genes involved in ethylene formation during somatic embryogenesis (SE). To investigate whether ethylene mediated by ACO is involved in the effect of TDZ on inhibition of embryogenic competence of the alfalfa callus. In this study we cloned full-length ACO cDNA from the alfalfa callus, named MsACO, and observed changes in this gene expression during callus formation and induction of SE under treatment with TDZ or TDZ plus CoCl₂. RNA blot analysis showed that during the EC subcultural period, the expression level of MsACO in EC was significantly increased on the 2nd day, rose to the highest level on the 8th day and remained at this high level until the 21st day. However, the ACO expression in the TDZ (0.93 μM)-treated callus was higher than in the EC especially on the 8th day. Moreover the ACO expression level increased with increasing TDZ concentration during the subcultural/maintenance period of the callus. It is worth noting that comparing the treatment with TDZ alone, the treatment with 0.93 μM TDZ plus 50 μM CoCl₂ reduced both of the ACO gene expressions and ACO activity in the treated callus. These results indicate that the effect of TDZ could be counteracted by CoCl₂ either on the ACO gene expression level or ACO activity. Thus, a TDZ inhibitory effect on embryogenic competence of alfalfa callus could be mediated by ACO gene expression. Crown Copyright © 2011. Published by Elsevier GmbH. All rights reserved.

Effect of cumin essential oil usage on fermentation quality, aerobic stability and in vitro digetibility of alfalfa silage.

PubMed

Turan, Aslı; Önenç, Sibel Soycan

2018-03-02

This study was carried out to determine the effects of cumin essential oil on the silage fermentation, aerobic stability and in vitro digestibility of alfalfa silages. Alfalfa was harvested at early bloom (5 th cutting) stage in October and wilted for about 3 hours. The research was carried out at three groups which were the control group where no additive control was done (CON), cumin essential oil (CMN3) with 300 mg/kg and CMN5 with 500 mg/kg cumin essential oil addition. Alfalfa was ensiled in plastic bags. The packages were stored at 8±2 °C under laboratory conditions. All groups were sampled for physical, chemical and microbiological analysis 120th day after ensiling. At the end of the ensiling period, all silages were subjected to an aerobic stability test for 7 days. In addition, enzimatic solubility of organic matter (ESOM), metabolizable energy (ME) and relative feed value (RFV) of these silages were determined. pH level decreased in the cumin groups compared to CON (P<0.05), thus inhibiting proteolytic enzymes from breaking down proteins into ammonia. In addition, it increased ESOM amount, and concordantly provided an increase of ME contents. Similarly, dry matter intake (DMI) and RFV ratio increased. After opening the silage, it kept its aerobic stability for three days. Cumin essential oil improved fermentation, and affected chemical and microbiological characteristics of silages. Especially the addition of 300 mg/kg cumin provided cell wall fractionation through stimulating the activities of enzymes responsible. It also increased the number and activity of lactic acid bacteri (LAB) through providing a development of LAB.

Low-fiber alfalfa (Medicago sativa L.) meal in the laying hen diet: effects on productive traits and egg quality.

PubMed

Laudadio, V; Ceci, E; Lastella, N M B; Introna, M; Tufarelli, V

2014-07-01

This study was designed to determine the effects on laying performance and egg quality resulting from partial substitution of soybean meal (SBM) with low-fiber alfalfa (LFA; Medicago sativa L.) meal in the diet of early-phase laying hens. ISA Brown layers, 18 wk of age, were randomly allocated to 2 dietary treatments and fed for 10 wk. The hens were fed 2 wheat middling-based diets: a control diet, which contained SBM (15% of diet), and a test diet containing LFA (15% of diet) as the main protein source. Low-fiber alfalfa meal was obtained by a combination of sieving and air-classification processes. Feed intake was recorded daily, and egg production was calculated on a hen-day basis; eggs from each group were weekly collected to evaluate egg components and quality. The partial substitution of SBM with LFA had no adverse effect on growth performance of early-phase laying hens. Egg production and none of the egg-quality traits examined were influenced by dietary treatment, except for yolk color (P < 0.001) and yolk percentage (P < 0.05) as well as yolk cholesterol and β-carotene contents (P < 0.001), which were improved in hens fed the LFA diet. Including LFA increased serum β-carotene and reduced serum cholesterol concentrations (P < 0.001). Our results suggest that partially replacing conventional SBM as protein source with low-fiber alfalfa meal in the laying-hen diet can positively influence yolk quality without adversely affecting productive traits. © 2014 Poultry Science Association Inc.

Concerted changes in N and C primary metabolism in alfalfa (Medicago sativa) under water restriction.

PubMed

Aranjuelo, Iker; Tcherkez, Guillaume; Molero, Gemma; Gilard, Françoise; Avice, Jean-Christophe; Nogués, Salvador

2013-02-01

Although the mechanisms of nodule N(2) fixation in legumes are now well documented, some uncertainty remains on the metabolic consequences of water deficit. In most cases, little consideration is given to other organs and, therefore, the coordinated changes in metabolism in leaves, roots, and nodules are not well known. Here, the effect of water restriction on exclusively N(2)-fixing alfalfa (Medicago sativa L.) plants was investigated, and proteomic, metabolomic, and physiological analyses were carried out. It is shown that the inhibition of nitrogenase activity caused by water restriction was accompanied by concerted alterations in metabolic pathways in nodules, leaves, and roots. The data suggest that nodule metabolism and metabolic exchange between plant organs nearly reached homeostasis in asparagine synthesis and partitioning, as well as the N demand from leaves. Typically, there was (i) a stimulation of the anaplerotic pathway to sustain the provision of C skeletons for amino acid (e.g. glutamate and proline) synthesis; (ii) re-allocation of glycolytic products to alanine and serine/glycine; and (iii) subtle changes in redox metabolites suggesting the implication of a slight oxidative stress. Furthermore, water restriction caused little change in both photosynthetic efficiency and respiratory cost of N(2) fixation by nodules. In other words, the results suggest that under water stress, nodule metabolism follows a compromise between physiological imperatives (N demand, oxidative stress) and the lower input to sustain catabolism.

A Mobile, Map-Based Tasking Interface for Human-Robot Interaction

DTIC Science & Technology

2010-12-01

A MOBILE, MAP-BASED TASKING INTERFACE FOR HUMAN-ROBOT INTERACTION By Eli R. Hooten Thesis Submitted to the Faculty of the Graduate School of...SUBTITLE A Mobile, Map-Based Tasking Interface for Human-Robot Interaction 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...3 II.1 Interactive Modalities and Multi-Touch . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 II.2

Alfalfa Intervention Alters Rumen Microbial Community Development in Hu Lambs During Early Life

PubMed Central

Yang, Bin; Le, Jiaqing; Wu, Peng; Liu, Jianxin; Guan, Le L.; Wang, Jiakun

2018-01-01

The pre-weaning period is crucial for rumen developmental plasticity, which can have a long-term impact on animal performance. Understanding the rumen microbiota during early life is important to elucidate its potential role in rumen development. In this study, the rumen microbiota of 10-day-old Hu lambs fed either milk replacer (B-10), milk replacer and starter (STA) or milk replacer and starter supplemented with alfalfa (S-ALF) in the pre- (d17, 24, and 38) and post-weaning periods (d45 and 66) were assessed to characterize rumen microbial colonization during early life and its response to fiber intervention. In the rumens of B-10 lambs, 498 operational taxonomic units belonging to 33 predominant genera were observed, and the top six predicted functions included “Membrane transport,” “carbohydrate metabolism,” “amino acid metabolism,” “replication and repair,” “translation,” and “energy metabolism.” Prevotella, Succinivibrio, Bifidobacterium, and Butyrivibrio abundances were increased at d38 for both STA and S-ALF groups compared to the B-10 group, whereas fibrolytic bacteria of the taxa Lachnospiraceae and Treponema were only increased in the S-ALF group at d38. A number of saccharolytic bacteria (Bacteroidaceae), organic acid-producing bacteria (Coprococcus and Actinomyces), proteolytic and amino acid fermenters (Fusobacterium) and fibrolytic bacteria (unclassified Ruminococcaceae) were significantly decreased in the STA lambs but not in the S-ALF lambs at d38. After weaning and exposed to alfalfa, the rumen microbial composition in the STA group started to appear similar to that of the S-ALF lambs. The relative abundance of unclassified Clostridiales was higher in S-ALF lambs than STA lambs after weaning. Spearman’s correlation analysis showed positive relationships between unclassified Lachnospiraceae, unclassified Clostridiales, Treponema, unclassified Bacteroidales, Coprococcus and crude protein intake, neutral detergent fiber

Effect of alfalfa (medicago sativa) on fermentation profile and nutritive value of switchgrass (panicum virgatum) and bermudagrass (cynodon dactylon) silages

USDA-ARS?s Scientific Manuscript database

An experiment was conducted at the University of Kentucky Spindletop Farm in Lexington, Kentucky between October and November, 2009 to evaluate the effect of different percentages of alfalfa (Medicago sativa) as mixtures in switchgrass (Panicum virgatus) and bermudagrass (Cynodon dactylon) silages. ...

Effects of finishing period length with vitamin E supplementation and alfalfa grazing on carcass color and the evolution of meat color and the lipid oxidation of light lambs.

PubMed

Ripoll, G; González-Calvo, L; Molino, F; Calvo, J H; Joy, M

2013-04-01

Indoor-kept concentrate-fed light lambs (n=54) were supplemented with 500 mg of dl-α-tocopheryl acetate/kg concentrate for 0, 10, 20 and 30 d before slaughtering at 22-24 kg BW. Simultaneously, 8 lambs with their dams were alfalfa-grazed and the lambs were slaughtered at the same weight. The age at slaughter and carcass characteristics were more affected by grazing than by supplementation with α-tocopherol. The grazing lambs had similar α-tocopherol levels to the lambs fed concentrate with dl-α-tocopheryl acetate for 10 days before slaughter. The length of the feeding period affected the evolution of the color, delaying the blooming and discoloration of the meat. Feeding lambs α-tocopherol enriched concentrate during the last 10 days of life or grazing them on alfalfa drastically diminished the lipid oxidation of the meat. Alfalfa grazing is a feasible alternative to increase light lamb meat shelf life without using additives. Copyright © 2012 Elsevier Ltd. All rights reserved.

Differential Attachment of Salmonella enterica and Enterohemorrhagic Escherichia coli to Alfalfa, Fenugreek, Lettuce, and Tomato Seeds

PubMed Central

Cui, Yue; Walcott, Ronald

2017-01-01

ABSTRACT Vegetable seeds have the potential to disseminate and transmit foodborne bacterial pathogens. This study was undertaken to assess the abilities of selected Salmonella and enterohemorrhagic Escherichia coli (EHEC) strains to attach to fungicide-treated versus untreated, and intact versus mechanically damaged, seeds of alfalfa, fenugreek, lettuce, and tomato. Surface-sanitized seeds (2 g) were exposed to four individual strains of Salmonella or EHEC at 20°C for 5 h. Contaminated seeds were rinsed twice, each with 10 ml of sterilized water, before being soaked overnight in 5 ml of phosphate-buffered saline at 4°C. The seeds were then vortexed vigorously for 1 min, and pathogen populations in seed rinse water and soaking buffer were determined using a standard plate count assay. In general, the Salmonella cells had higher attachment ratios than the EHEC cells. Lettuce seeds by unit weight had the highest numbers of attached Salmonella or EHEC cells, followed by tomato, alfalfa, and fenugreek seeds. In contrast, individual fenugreek seeds had more attached pathogen cells, followed by lettuce, alfalfa, and tomato seeds. Significantly more Salmonella and EHEC cells attached to mechanically damaged seeds than to intact seeds (P < 0.05). Although, on average, significantly more Salmonella and EHEC cells were recovered from untreated than fungicide-treated seeds (P < 0.05), fungicide treatment did not significantly affect the attachment of individual bacterial strains to vegetable seeds (P > 0.05), with a few exceptions. This study fills gaps in the current body of literature and helps explain bacterial interactions with vegetable seeds with differing surface characteristics. IMPORTANCE Vegetable seeds, specifically sprout seeds, have the potential to disseminate and transmit foodborne bacterial pathogens. This study investigated the interaction between two important bacterial pathogens, i.e., Salmonella and EHEC, and vegetable seeds with differing surface

Differential Attachment of Salmonella enterica and Enterohemorrhagic Escherichia coli to Alfalfa, Fenugreek, Lettuce, and Tomato Seeds.

PubMed

Cui, Yue; Walcott, Ronald; Chen, Jinru

2017-04-01

Vegetable seeds have the potential to disseminate and transmit foodborne bacterial pathogens. This study was undertaken to assess the abilities of selected Salmonella and enterohemorrhagic Escherichia coli (EHEC) strains to attach to fungicide-treated versus untreated, and intact versus mechanically damaged, seeds of alfalfa, fenugreek, lettuce, and tomato. Surface-sanitized seeds (2 g) were exposed to four individual strains of Salmonella or EHEC at 20°C for 5 h. Contaminated seeds were rinsed twice, each with 10 ml of sterilized water, before being soaked overnight in 5 ml of phosphate-buffered saline at 4°C. The seeds were then vortexed vigorously for 1 min, and pathogen populations in seed rinse water and soaking buffer were determined using a standard plate count assay. In general, the Salmonella cells had higher attachment ratios than the EHEC cells. Lettuce seeds by unit weight had the highest numbers of attached Salmonella or EHEC cells, followed by tomato, alfalfa, and fenugreek seeds. In contrast, individual fenugreek seeds had more attached pathogen cells, followed by lettuce, alfalfa, and tomato seeds. Significantly more Salmonella and EHEC cells attached to mechanically damaged seeds than to intact seeds ( P < 0.05). Although, on average, significantly more Salmonella and EHEC cells were recovered from untreated than fungicide-treated seeds ( P < 0.05), fungicide treatment did not significantly affect the attachment of individual bacterial strains to vegetable seeds ( P > 0.05), with a few exceptions. This study fills gaps in the current body of literature and helps explain bacterial interactions with vegetable seeds with differing surface characteristics. IMPORTANCE Vegetable seeds, specifically sprout seeds, have the potential to disseminate and transmit foodborne bacterial pathogens. This study investigated the interaction between two important bacterial pathogens, i.e., Salmonella and EHEC, and vegetable seeds with differing surface

Transformation with TT8 and HB12 RNAi Constructs in Model Forage (Medicago sativa, Alfalfa) Affects Carbohydrate Structure and Metabolic Characteristics in Ruminant Livestock Systems.

PubMed

Li, Xinxin; Zhang, Yonggen; Hannoufa, Abdelali; Yu, Peiqiang

2015-11-04

Lignin, a phenylpropanoid polymer present in secondary cell walls, has a negative impact on feed digestibility. TT8 and HB12 genes were shown to have low expression levels in low-lignin tissues of alfalfa, but to date, there has been no study on the effect of down-regulation of these two genes in alfalfa on nutrient chemical profiles and availability in ruminant livestock systems. The objectives of this study were to investigate the effect of transformation of alfalfa with TT8 and HB12 RNAi constructs on carbohydrate (CHO) structure and CHO nutritive value in ruminant livestock systems. The results showed that transformation with TT8 and HB12 RNAi constructs reduced rumen, rapidly degraded CHO fractions (RDCA4, P = 0.06; RDCB1, P < 0.01) and totally degraded CHO fraction (TRDCHO, P = 0.08). Both HB12 and TT8 populations had significantly higher in vitro digestibility of neutral detergent fiber (NDF) at 30 h of incubation (ivNDF30) compared to the control (P < 0.01). The TT8 populations had highest ivDM30 and ivNDF240. Transformation of alfalfa with TT8 and HB12 RNAi constructs induced molecular structure changes. Different CHO functional groups had different sensitivities and different responses to the transformation. The CHO molecular structure changes induced by the transformation were associated with predicted CHO availability. Compared with HB12 RNAi, transformation with TT8 RNAi could improve forage quality by increasing the availability of both NDF and DM. Further study is needed on the relationship between the transformation-induced structure changes at a molecular level and nutrient utilization in ruminant livestock systems when lignification is much higher.

Multi-Task Project to Provide Research Support for Human Research and Engineering Goals Identified by the Army

DTIC Science & Technology

2009-06-01

Jefferson City, MO Phone:573-681-5126 E-mail: rooneyi(a>lincolnu.edu Principle Investigators for contract’s 5 Task Areas: Task I : James Rooney...identified Tasks all structured within a single contract. This contract contained Five Task areas: Task I was an administrative task; Task II-V were...Manager’s Overview of the Report (Task I ) 3. Summary Final Budget Invoice and Budget unspent balance 4. Technical Reports of the Research Tasks (II - V

Overexpression of Medicago sativa TMT elevates the α-tocopherol content in Arabidopsis seeds, alfalfa leaves, and delays dark-induced leaf senescence.

PubMed

Jiang, Jishan; Jia, Huili; Feng, Guangyan; Wang, Zan; Li, Jun; Gao, Hongwen; Wang, Xuemin

2016-08-01

Alfalfa (Medicago sativa L.) is a major forage legume for livestock and a target for improving their dietary quality. Vitamin E is an essential vitamin that animals must obtain from their diet for proper growth and development. γ-tocopherol methyltransferase (γ-TMT), which catalyzes the conversion of δ- and γ-tocopherols (or tocotrienols) to β- and α-tocopherols (or tocotrienols), respectively, is the final enzyme involved in the vitamin E biosynthetic pathway. The overexpression of M. sativa L.'s γ-TMT (MsTMT) increased the α-tocopherol content 10-15 fold above that of wild type Arabidopsis seeds without altering the total content of vitamin E. Additionally, in response to osmotic stress, the biomass and the expression levels of several osmotic marker genes were significantly higher in the transgenic lines compared with wild type. Overexpression of MsTMT in alfalfa led to a modest, albeit significant, increase in α-tocopherol in leaves and was also responsible for a delayed leaf senescence phenotype. Additionally, the crude protein content was increased, while the acid and neutral detergent fiber contents were unchanged in these transgenic lines. Thus, increased α-tocopherol content occurred in transgenic alfalfa without compromising the nutritional qualities. The targeted metabolic engineering of vitamin E biosynthesis through MsTMT overexpression provides a promising approach to improve the α-tocopherol content of forage crops. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Study of the heavy metal phytoextraction capacity of two forage species growing in an hydroponic environment.

PubMed

Bonfranceschi, Barros A; Flocco, C G; Donati, E R

2009-06-15

Sorghum and alfalfa are two important forage crops. We studied their capacity for accumulating heavy metals in hydroponic experiments. Cadmium, nickel (as divalent cations) and chromium (trivalent and hexavalent) were added individually to the nutrient solution in a range of concentrations from 1 to 80 mg/l. Cr(III) was complexed with EDTA to increase its bioavailability. In alfalfa the increases in the concentration of Cr(III) and Cr(VI) favoured translocation of the metals to the upper parts of the plants, while with Ni(II) the level of translocated metal remained almost unchanged. In sorghum, both Cr(VI) and Ni(II) produced similar results to those in alfalfa, but increases in the concentrations of Cd(II) and Cr(III) in the solution lead to a higher accumulation of the metal at the root level. The concentrations referred to the dry biomass of alfalfa were 500 mg/kg (aerial parts) and 1500 mg/kg (roots) of Cr(III), simultaneously enhancing plant growth. Sorghum captured 500 and 1100 mg/kg (in aerial parts) and 300 and 2000 mg/kg (in roots) for Ni(II) and Cd(II) respectively, without significant damage to its biomass. The results show that alfalfa and sorghum can not only grow in the presence of high heavy metal concentration but also capture and translocate them to the aerial parts; because of these results special attention should be given to these crop plants for their possible use in phytoremediation of large contaminated areas but especially to avoid the possible introduction of the metals accumulated in aerial parts into the food chain when those plants grow in contaminated areas.

Distribution in the Western United States on Alfalfa and Cultivar Reaction to Mixed Populations of Ditylenchus dipsaci and Aphelenchoides ritzemabosi

PubMed Central

Gray, F. A.; Williams, J. L.; Griffin, G. D.; Wilson, T. E.

1994-01-01

Ditylenchus dipsaci and Aphelenchoides ritzemabosi were extracted from 29 of 40 plant samples (72.5%) collected from Arizona, California, Colorado, Idaho, Montana, Oregon, South Dakota, Utah, Washington, and Wyoming. Percentages of A. ritzemabosi in tissue of the 29 samples ranged from 1.77 to 67.82%. Only Ditylenchus dipsaci was recovered from the remaining 11 samples. All of the 16 fields sampled in Wyoming contained both nematodes. Percentages of A. ritzemabosi in the Wyoming samples ranged from 0.7-30.0%, with an overall mean of 10.3%. Individual plants collected from a field in Big Horn, Wyoming, all contained both nematodes. Percentages of A. ritzemabosi in tissue ranged from 5-70%. Alfalfa stem nematode symptomatic plants in 17 of 18 alfalfa cultivars collected from a screening nursery in California contained both nematodes, of which 10-94% were A. ritzemabosi. Only one cultivar had D. dipsaci only, and no entries had A. ritzemabosi only. Under environmentally controlled conditions, A. ritzemabosi reproduced in all nine alfalfa cultivars tested at 6 weeks of age with a mean reproductive factor (final population/initial population) of 4.1. There were more (P ≤ 0.05) A. ritzemabosi in stem and bud tissue of the susceptible cultivars at harvest than in the resistant cultivars with combined cultivar means of 238, 42, 78, and 4 A. ritzemabosi/g tissue for the susceptible, moderately resistant, resistant, and highly resistant cultivars, respectively. Percentage A. ritzemabosi in tissues decreased over time in seedlings but increased in older plants. PMID:19279952

The similar effects of verbal and non-verbal intervening tasks on word recall in an elderly population.

PubMed

Williams, B R; Sullivan, S K; Morra, L F; Williams, J R; Donovick, P J

2014-01-01

Vulnerability to retroactive interference has been shown to increase with cognitive aging. Consistent with the findings of memory and aging literature, the authors of the California Verbal Learning Test-II (CVLT-II) suggest that a non-verbal task be administered during the test's delay interval to minimize the effects of retroactive interference on delayed recall. The goal of the present study was to determine the extent to which retroactive interference caused by non-verbal and verbal intervening tasks affects recall of verbal information in non-demented, older adults. The effects of retroactive interference on recall of words during Long-Delay recall on the California Verbal Learning Test-II (CVLT-II) were evaluated. Participants included 85 adults age 60 and older. During a 20-minute delay interval on the CVLT-II, participants received either a verbal (WAIS-III Vocabulary or Peabody Picture Vocabulary Test-IIIB) or non-verbal (Raven's Standard Progressive Matrices or WAIS-III Block Design) intervening task. Similarly to previous research with young adults (Williams & Donovick, 2008), older adults recalled the same number of words across all groups, regardless of the type of intervening task. These findings suggest that the administration of verbal intervening tasks during the CVLT-II do not elicit more retroactive interference than non-verbal intervening tasks, and thus verbal tasks need not be avoided during the delay interval of the CVLT-II.

Reduction of Salmonella on alfalfa seeds using peroxyacetic acid and a commercial seed washer is as effective as treatment with 20 000 ppm of Ca(OCl)2.

PubMed

Buchholz, A; Matthews, K R

2010-10-01

The efficacy of a commercial seed washer and 1 and 3% peroxyacetic acid or 20 000 ppm calcium hypochlorite for reducing Salmonella on alfalfa seeds was investigated. Alfalfa seeds were inoculated with Salmonella Stanley to achieve c. 5 log CFU g(-1). Seeds were then treated with 1 or 3% peroxyacetic acid or 20 000 ppm calcium hypochlorite for 15 min in a commercial seed washer that uses air to enhance contact of the sanitizer with the seed. Experiments were also conducted using industry and laboratory methods. An c. 1-log reduction in number of Salm. Stanley was demonstrated regardless of the chemical treatment or method of treatment. Although this 1-log reduction was significant (P < 0.05), differences among the treatments were not significant. Treating the seed with 1 and 3% peroxyacetic acid resulted in similar Salm. Stanley reductions of 1.77 and 1.34 log, respectively, not being statistically significant (P > 0.05). These results suggest that under conditions tested, 1 or 3% peroxyacetic acid solutions are equally effective as 20 000 ppm of Ca(OCl)2 in the reduction of Salm. Stanley on alfalfa seed when used in conjunction with a commercial seed washer. A 1% peroxyacetic acid solution could potentially be used in place of 20 000 ppm of Ca(OCl)2 for treatment of seeds used for sprouting. The commercial seed washer did not enhance removal of Salm. Stanley from alfalfa seeds, but did facilitate removal of excess soil from seeds. © 2010 The Authors. Journal compilation © 2010 The Society for Applied Microbiology.

The isoflavone content of two new alfalfa-derived products for instant beverage preparation.

PubMed

Soto-Zarazúa, M Guadalupe; Rodrigues, Francisca; Pimentel, Filipa B; Bah, M M; Oliveira, M Beatriz P P

2016-01-01

The frequent use of plant-based products to promote health leads to the search for scientific information related to efficacy and safety of those products for human consumption. Two alfalfa-derived products (ADP), freeze-dried juice (FDJ) and dehydrated powder (DP), from alfalfa harvested in Mexico, are being developed as new possible nutraceuticals. To the best of our knowledge, any study reports the real composition of such products used to prepare instant beverages in what concerns isoflavone contents. Seven isoflavones (glycitein, formononetin, biochanin A, daidzein, genistein, daidzin and genistin) were assessed by HPLC-DAD analysis as well as its variation in five different batches of these products. Different solvents were tested in order to choose the best one to extract isoflavones. The results showed the presence of daidzein, genistein, genistin and daidzin in most samples while glycitein, formononetin and biochanin A were not detected. Significant differences between isoflavone contents were found with different solvent systems. Water was the best option to extract daidzein (0.40-1.08 mg per unit and 1.30-4.90 mg per unit for DP and FDJ, respectively) whereas the water-methanol-formic acid mixture was efficient to extract genistein (0.19-0.43 mg per unit and 0.15-0.72 mg per unit for DP and FDJ, respectively). In all cases, the total isoflavone content was higher in freeze-dried juices than in dehydrated powders. Genistein and daidzein were the more abundant isoflavones quantified. Further physiological and nutritional studies are needed to complete the validation of effectiveness and safety of these products.

Cloning and characterization of a heme oxygenase-2 gene from alfalfa (Medicago sativa L.).

PubMed

Fu, Guang-Qing; Jin, Qi-Jiang; Lin, Yu-Ting; Feng, Jian-Fei; Nie, Li; Shen, Wen-Biao; Zheng, Tian-Qing

2011-11-01

Heme oxygenase (HO, EC 1.14.99.3) catalyzes the oxidation of heme and performs vital roles in plant development and stress responses. Two HO isozymes exist in plants. Between these, HO-1 is an oxidative stress-response protein, and HO-2 usually exhibited constitutive expression. Although alfalfa HO-1 gene (MsHO1) has been investigated previously, HO2 is still poorly understood. In this study, we report the cloning and characterization of HO2 gene, MsHO2, from alfalfa (Medica sativa L.). The full-length cDNA of MsHO2 contains an ORF of 870 bp and encodes for 290 amino acid residues with a predicted molecular mass of 33.3 kDa. Similar to MsHO1, MsHO2 also appears to have an N-terminal transit peptide sequence for chloroplast import. Many conserved residues in plant HO were also conserved in MsHO2. However, unlike HO-1, the conserved histidine (His) required for heme-iron binding and HO activity was replaced by tyrosine (Tyr) in MsHO2. Further biochemical activity analysis of purified mature MsHO2 showed no HO activity, suggesting that MsHO2 may not be a true HO in nature. Semi-quantitative RT-PCR confirmed its maximum expression in the germinating seeds. Importantly, the expression levels of MsHO2 were up-regulated under sodium nitroprusside (SNP) and H(2)O(2) (especially) treatment, respectively.

The alfalfa “almost darks” campaign: Pilot VLA HI observations of five high mass-to-light ratio systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cannon, John M.; Martinkus, Charlotte P.; Leisman, Lukas

We present new Very Large Array (VLA) H i spectral line imaging of five sources discovered by the ALFALFA extragalactic survey. These targets are drawn from a larger sample of systems that were not uniquely identified with optical counterparts during ALFALFA processing, and as such have unusually high H i mass to light ratios. The candidate “Almost Dark” objects fall into four broad categories: (1) objects with nearby H i neighbors that are likely of tidal origin; (2) objects that appear to be part of a system of multiple H i sources, but which may not be tidal in origin;more » (3) objects isolated from nearby ALFALFA H i detections, but located near a gas-poor early type galaxy; (4) apparently isolated sources, with no object of coincident redshift within ∼400 kpc. Roughly 75% of the 200 objects without identified counterparts in the α.40 database (Haynes et al. 2011) fall into category 1 (likely tidal), and were not considered for synthesis follow-up observations. The pilot sample presented here (AGC193953, AGC208602, AGC208399, AGC226178, and AGC233638) contains the first five sources observed as part of a larger effort to characterize H i sources with no readily identifiable optical counterpart at single dish resolution (3.′5). These objects span a range of H i mass [7.41 < log(M{sub Hi}) < 9.51] and H i mass to B-band luminosity ratios (3 < M{sub Hi}/L{sub B} < 9). We compare the H i total intensity and velocity fields to optical imaging drawn from the Sloan Digital Sky Survey and to ultraviolet imaging drawn from archival GALEX observations. Four of the sources with uncertain or no optical counterpart in the ALFALFA data are identified with low surface brightness optical counterparts in Sloan Digital Sky Survey imaging when compared with VLA H i intensity maps, and appear to be galaxies with clear signs of ordered rotation in the H i velocity fields. Three of these are detected in far-ultraviolet GALEX images, a likely indication of star formation

Genome-Wide Association Study Identifies Loci for Salt Tolerance during Germination in Autotetraploid Alfalfa (Medicargo sativa L.) using Genotyping by Sequencing

USDA-ARS?s Scientific Manuscript database

: In this study, we used a diverse panel of alfalfa accessions to identify molecular markers associated with salt tolerance during germination by genome-wide association (GWA) mapping and genotyping-by-sequencing (GBS). Three levels of salt treatments were applied during seed germination. Phenotypic...

Formulation of enzyme blends to maximize the hydrolysis of alkaline peroxide pretreated alfalfa hay and barley straw by rumen enzymes and commercial cellulases

PubMed Central

2014-01-01

Background Efficient conversion of lignocellulosic biomass to fermentable sugars requires the synergistic action of multiple enzymes; consequently enzyme mixtures must be properly formulated for effective hydrolysis. The nature of an optimal enzyme blends depends on the type of pretreatment employed as well the characteristics of the substrate. In this study, statistical experimental design was used to develop mixtures of recombinant glycosyl hydrolases from thermophilic and anaerobic fungi that enhanced the digestion of alkaline peroxide treated alfalfa hay and barley straw by mixed rumen enzymes as well as commercial cellulases (Accelerase 1500, A1500; Accelerase XC, AXC). Results Combinations of feruloyl and acetyl xylan esterases (FAE1a; AXE16A_ASPNG), endoglucanase GH7 (EGL7A_THITE) and polygalacturonase (PGA28A_ASPNG) with rumen enzymes improved straw digestion. Inclusion of pectinase (PGA28A_ASPNG), endoxylanase (XYN11A_THITE), feruloyl esterase (FAE1a) and β-glucosidase (E-BGLUC) with A1500 or endoglucanase GH7 (EGL7A_THITE) and β-xylosidase (E-BXSRB) with AXC increased glucose release from alfalfa hay. Glucose yield from straw was improved when FAE1a and endoglucanase GH7 (EGL7A_THITE) were added to A1500, while FAE1a and AXE16A_ASPNG enhanced the activity of AXC on straw. Xylose release from alfalfa hay was augmented by supplementing A1500 with E-BGLUC, or AXC with EGL7A_THITE and XYN11A_THITE. Adding arabinofuranosidase (ABF54B_ASPNG) and esterases (AXE16A_ASPNG; AXE16B_ASPNG) to A1500, or FAE1a and AXE16A_ASPNG to AXC enhanced xylose release from barley straw, a response confirmed in a scaled up assay. Conclusion The efficacy of commercial enzyme mixtures as well as mixed enzymes from the rumen was improved through formulation with synergetic recombinant enzymes. This approach reliably identified supplemental enzymes that enhanced sugar release from alkaline pretreated alfalfa hay and barley straw. PMID:24766728

Formulation of enzyme blends to maximize the hydrolysis of alkaline peroxide pretreated alfalfa hay and barley straw by rumen enzymes and commercial cellulases.

PubMed

Badhan, Ajay; Wang, Yuxi; Gruninger, Robert; Patton, Donald; Powlowski, Justin; Tsang, Adrian; McAllister, Tim

2014-04-26

Efficient conversion of lignocellulosic biomass to fermentable sugars requires the synergistic action of multiple enzymes; consequently enzyme mixtures must be properly formulated for effective hydrolysis. The nature of an optimal enzyme blends depends on the type of pretreatment employed as well the characteristics of the substrate. In this study, statistical experimental design was used to develop mixtures of recombinant glycosyl hydrolases from thermophilic and anaerobic fungi that enhanced the digestion of alkaline peroxide treated alfalfa hay and barley straw by mixed rumen enzymes as well as commercial cellulases (Accelerase 1500, A1500; Accelerase XC, AXC). Combinations of feruloyl and acetyl xylan esterases (FAE1a; AXE16A_ASPNG), endoglucanase GH7 (EGL7A_THITE) and polygalacturonase (PGA28A_ASPNG) with rumen enzymes improved straw digestion. Inclusion of pectinase (PGA28A_ASPNG), endoxylanase (XYN11A_THITE), feruloyl esterase (FAE1a) and β-glucosidase (E-BGLUC) with A1500 or endoglucanase GH7 (EGL7A_THITE) and β-xylosidase (E-BXSRB) with AXC increased glucose release from alfalfa hay. Glucose yield from straw was improved when FAE1a and endoglucanase GH7 (EGL7A_THITE) were added to A1500, while FAE1a and AXE16A_ASPNG enhanced the activity of AXC on straw. Xylose release from alfalfa hay was augmented by supplementing A1500 with E-BGLUC, or AXC with EGL7A_THITE and XYN11A_THITE. Adding arabinofuranosidase (ABF54B_ASPNG) and esterases (AXE16A_ASPNG; AXE16B_ASPNG) to A1500, or FAE1a and AXE16A_ASPNG to AXC enhanced xylose release from barley straw, a response confirmed in a scaled up assay. The efficacy of commercial enzyme mixtures as well as mixed enzymes from the rumen was improved through formulation with synergetic recombinant enzymes. This approach reliably identified supplemental enzymes that enhanced sugar release from alkaline pretreated alfalfa hay and barley straw.

Disinfection of radish and alfalfa seeds inoculated with Escherichia coli O157:H7 and Salmonella by a gaseous acetic acid treatment.

PubMed

Nei, Daisuke; Latiful, Bari M; Enomoto, Katsuyoshi; Inatsu, Yasuhiro; Kawamoto, Shinnichi

2011-10-01

Abstract The majority of seed sprout-related outbreaks have been associated with Escherichia coli O157:H7 and Salmonella. Therefore, we aimed to find an effective method to inactivate these organisms on seeds before sprouting. Treatment with 8.7% (v/v) acetic acid at 55°C for 2-3 h reduced the population of E. coli O157:H7 and Salmonella inoculated on alfalfa (Medicago sativa L.) and radish seeds (Raphanus sativus L.) by more than 5.0 log CFU/g, and a longer treatment time completely eliminated the E. coli O157:H7 population. The E. coli O157:H7 populations were reduced to an undetectable level with a gaseous acetic acid treatment for 48 h. After enrichment, no E. coli O157:H7 were found in the alfalfa and radish seeds (25 g). However, these treatments were unable to eliminate Salmonella in both seed types. No significant difference between the germination rates of treated alfalfa seeds and control seeds was found, and germination rates greater than 95% were obtained for the radish seeds. Although chlorine washing is commonly used for seed decontamination, chlorine washing at 200 and 20,000 ppm resulted in a reduction of pathogens by less than or equal to 3 log CFU/g. Therefore, these results suggested that gaseous acetic acid is more effective than chlorine washing in controlling pathogenic bacteria on sprout seeds.

Concerted changes in N and C primary metabolism in alfalfa (Medicago sativa) under water restriction

PubMed Central

Aranjuelo, Iker

2013-01-01

Although the mechanisms of nodule N2 fixation in legumes are now well documented, some uncertainty remains on the metabolic consequences of water deficit. In most cases, little consideration is given to other organs and, therefore, the coordinated changes in metabolism in leaves, roots, and nodules are not well known. Here, the effect of water restriction on exclusively N2-fixing alfalfa (Medicago sativa L.) plants was investigated, and proteomic, metabolomic, and physiological analyses were carried out. It is shown that the inhibition of nitrogenase activity caused by water restriction was accompanied by concerted alterations in metabolic pathways in nodules, leaves, and roots. The data suggest that nodule metabolism and metabolic exchange between plant organs nearly reached homeostasis in asparagine synthesis and partitioning, as well as the N demand from leaves. Typically, there was (i) a stimulation of the anaplerotic pathway to sustain the provision of C skeletons for amino acid (e.g. glutamate and proline) synthesis; (ii) re-allocation of glycolytic products to alanine and serine/glycine; and (iii) subtle changes in redox metabolites suggesting the implication of a slight oxidative stress. Furthermore, water restriction caused little change in both photosynthetic efficiency and respiratory cost of N2 fixation by nodules. In other words, the results suggest that under water stress, nodule metabolism follows a compromise between physiological imperatives (N demand, oxidative stress) and the lower input to sustain catabolism. PMID:23440170

The ALFALFA Extragalactic Catalog and Data Processing Pipeline

NASA Astrophysics Data System (ADS)

Kent, Brian R.; Haynes, Martha P.; Giovanelli, Riccardo; ALFALFA Team

2018-06-01

The Arecibo Legacy Fast ALFA 21cm HI Survey has reached completion. The observations and data are used by team members and the astronomical community in a variety of scientific initiatives with gas-rich galaxies, cluster environments, and studies of low redshift cosmology. The survey covers nearly 7000 square degrees of high galactic latitude sky visible from Arecibo, Puerto Rico and ~4400 hours of observations from 2005 to 2011. We present the extragalactic HI source catalog of over ~31,000 detections, their measured properties, and associated derived parameters. The observations were carefully reduced using a custom made data reduction pipeline and interface. Team members interacted with this pipeline through observation planning, calibration, imaging, source extraction, and cataloging. We describe this processing workflow as it pertains to the complexities of the single-dish multi-feed data reduction as well as known caveats of the source catalog and spectra for use in future astronomical studies and analysis. The ALFALFA team at Cornell has been supported by NSF grants AST-0607007, AST-1107390 and AST-1714828 and by grants from the Brinson Foundation.

Effect of delayed wrapping and wrapping source on nitrogen balance and blood urea nitrogen in gestating sheep offered alfalfa silage

USDA-ARS?s Scientific Manuscript database

Exposing ensiled forage to oxygen can result in DM deterioration and reduce silage intake by animals. This study was conducted to investigate the effects of 2 different wrapping sources and time intervals between baling and wrapping on N balance and blood urea N in gestating sheep offered alfalfa si...

Replacing alfalfa or red clover silage with birdsfoot trefoil silage in total mixed rations increases production of lactating dairy cows

USDA-ARS?s Scientific Manuscript database

The objective of this study was to compare effects of feeding silage made from birdsfoot trefoil (BFT), selected for low (LBFT), normal (NBFT) and high (HBFT) levels of condensed tannins (CT), to feeding silage made from alfalfa (AL) or red clover (RC) on milk production and nutrient utilization in ...

Designing Preclinical Instruction for Psychomotor Skills (II)--Instructional Engineering: Task Analysis.

ERIC Educational Resources Information Center

Knight, G. William; And Others

1994-01-01

The first step in engineering the instruction of dental psychomotor skills, task analysis, is explained. A chart details the procedural, cognitive, desired-criteria, and desired-performance analysis of a single task, occlusal preparation for amalgam restoration with carious lesion. (MSE)

Efficacy of chemical treatments in eliminating Salmonella and Escherichia coli O157:H7 on scarified and polished alfalfa seeds.

PubMed

Holliday, S L; Scouten, A J; Beuchat, L R

2001-10-01

Alfalfa seeds are sometimes subjected to a scarification treatment to enhance water uptake, which results in more rapid and uniform germination during sprout production. It has been hypothesized that this mechanical abrasion treatment diminishes the efficacy of chemical treatments used to kill or remove pathogenic bacteria from seeds. A study was done to compare the effectiveness of chlorine (20,000 ppm), H2O, (8%), Ca(OH)2 (1%), Ca(OH)2 (1%) plus Tween 80 (1%), and Ca(OH)2 (1%) plus Span 20 (1%) treatments in killing Salmonella and Escherichia coli O157:H7 inoculated onto control, scarified, and polished alfalfa seeds obtained from two suppliers. The influence of the presence of organic material in the inoculum carrier on the efficacy of sanitizers was investigated. Overall, treatment with 1% Ca(OH)2 was the most effective in reducing populations of the pathogens. Reduction in populations of pathogens on seeds obtained from supplier I indicate that chemical treatments are less efficacious in eliminating the pathogens on scarified seeds compared to control seeds. However, the effectiveness of chemical treatment in removing Salmonella and E. coli O157:H7 from seeds obtained from supplier 2 was not markedly affected by scarification or polishing. The presence of organic material in the inoculum carrier did not have a marked influence on the efficacy of chemicals in reducing populations of test pathogens. Additional lots of control, scarified, and polished alfalfa seeds of additional varieties need to be tested before conclusions can be drawn concerning the impact of mechanical abrasion on the efficacy of chemical treatment in removing or killing Salmonella and E. coli O157:H7.

The NSF Undergraduate ALFALFA Team: Partnering with Arecibo Observatory to Offer Undergraduate and Faculty Extragalactic Radio Astronomy Research Opportunities

NASA Astrophysics Data System (ADS)

Ribaudo, Joseph; Koopmann, Rebecca A.; Haynes, Martha P.; Balonek, Thomas J.; Cannon, John M.; Coble, Kimberly A.; Craig, David W.; Denn, Grant R.; Durbala, Adriana; Finn, Rose; Hallenbeck, Gregory L.; Hoffman, G. Lyle; Lebron, Mayra E.; Miller, Brendan P.; Crone-Odekon, Mary; O'Donoghue, Aileen A.; Olowin, Ronald Paul; Pantoja, Carmen; Pisano, Daniel J.; Rosenberg, Jessica L.; Troischt, Parker; Venkatesan, Aparna; Wilcots, Eric M.; ALFALFA Team

2017-01-01

The NSF-sponsored Undergraduate ALFALFA (Arecibo Legacy Fast ALFA) Team (UAT) is a consortium of 20 institutions across the US and Puerto Rico, founded to promote undergraduate research and faculty development within the extragalactic ALFALFA HI blind survey project and follow-up programs. The objective of the UAT is to provide opportunities for its members to develop expertise in the technical aspects of observational radio spectroscopy, its associated data analysis, and the motivating science. Partnering with Arecibo Observatory, the UAT has worked with more than 280 undergraduates and 26 faculty to date, offering 8 workshops onsite at Arecibo (148 undergraduates), observing runs at Arecibo (69 undergraduates), remote observing runs on campus, undergraduate research projects based on Arecibo science (120 academic year and 185 summer projects), and presentation of results at national meetings such as the AAS (at AAS229: Ball et al., Collova et al., Davis et al., Miazzo et al., Ruvolo et al, Singer et al., Cannon et al., Craig et al., Koopmann et al., O'Donoghue et al.). 40% of the students and 45% of the faculty participants have been women and members of underrepresented groups. More than 90% of student alumni are attending graduate school and/or pursuing a career in STEM. 42% of those pursuing graduate degrees in Physics or Astronomy are women.In this presentation, we summarize the UAT program and the current research efforts of UAT members based on Arecibo science, including multiwavelength followup observations of ALFALFA sources, the UAT Collaborative Groups Project, the Survey of HI in Extremely Low-mass Dwarfs (SHIELD), and the Arecibo Pisces-Perseus Supercluster Survey (APPSS). This work has been supported by NSF grants AST-0724918/0902211, AST-075267/0903394, AST-0725380, AST-121105, and AST-1637339.

MsZEP, a novel zeaxanthin epoxidase gene from alfalfa (Medicago sativa), confers drought and salt tolerance in transgenic tobacco.

PubMed

Zhang, Zhiqiang; Wang, Yafang; Chang, Leqin; Zhang, Tong; An, Jie; Liu, Yushi; Cao, Yuman; Zhao, Xia; Sha, Xuyang; Hu, Tianming; Yang, Peizhi

2016-02-01

The zeaxanthin epoxidase gene ( MsZEP ) was cloned and characterized from alfalfa and validated for its function of tolerance toward drought and salt stresses by heterologous expression in Nicotiana tabacum. Zeaxanthin epoxidase (ZEP) plays important roles in plant response to various environment stresses due to its functions in ABA biosynthetic and the xanthophyll cycle. To understand the expression characteristics and the biological functions of ZEP in alfalfa (Medicago sativa), a novel gene, designated as MsZEP (KM044311), was cloned, characterized and overexpressed in Nicotiana tabacum. The open reading frame of MsZEP contains 1992 bp nucleotides and encodes a 663-amino acid polypeptide. Amino acid sequence alignment indicated that deduced MsZEP protein was highly homologous to other plant ZEP sequences. Phylogenetic analysis showed that MsZEP was grouped into a branch with other legume plants. Real-time quantitative PCR revealed that MsZEP gene expression was clearly tissue-specific, and the expression levels were higher in green tissues (leaves and stems) than in roots. MsZEP expression decreased in shoots under drought, cold, heat and ABA treatment, while the expression levels in roots showed different trends. Besides, the results showed that nodules could up-regulate the MsZEP expression under non-stressful conditions and in the earlier stage of different abiotic stress. Heterologous expression of the MsZEP gene in N. tabacum could confer tolerance to drought and salt stress by affecting various physiological pathways, ABA levels and stress-responsive genes expression. Taken together, these results suggested that the MsZEP gene may be involved in alfalfa responses to different abiotic stresses and nodules, and could enhance drought and salt tolerance of transgenic tobacco by heterologous expression.

From H I to Stars: H I Depletion in Starbursts and Star-forming Galaxies in the ALFALFA Hα Survey

NASA Astrophysics Data System (ADS)

Jaskot, A. E.; Oey, M. S.; Salzer, J. J.; Van Sistine, A.; Bell, E. F.; Haynes, M. P.

2015-07-01

H i in galaxies traces the fuel for future star formation and reveals the effects of feedback on neutral gas. Using a statistically uniform, H i-selected sample of 565 galaxies from the Arecibo Legacy Fast ALFA (ALFALFA) Hα survey, we explore H i properties as a function of star formation activity. ALFALFA Hα provides R-band and Hα imaging for a volume-limited subset of the 21 cm ALFALFA survey. We identify eight starbursts based on Hα equivalent width and six with enhanced star formation relative to the main sequence. Both starbursts and non-starbursts have similar H i-to-stellar mass ratios ({M}{{H} {{I}}}/{M}*), which suggests that feedback is not depleting the starbursts’ H i. Consequently, the starbursts do have shorter H i depletion times ({t}{dep}), implying more efficient H i-to-H2 conversion. While major mergers likely drive this enhanced efficiency in some starbursts, the lowest-mass starbursts may experience periodic bursts, consistent with enhanced scatter in {t}{dep} at low {M}*. Two starbursts appear to be pre-coalescence mergers; their elevated {M}{{H} {{I}}}/{M}* suggest that H i-to-H2 conversion is still ongoing at this stage. By comparing with the GASS sample, we find that {t}{dep} anticorrelates with stellar surface density for disks, while spheroids show no such trend. Among early-type galaxies, {t}{dep} does not correlate with bulge-to-disk ratio; instead, the gas distribution may determine the star formation efficiency. Finally, the weak connection between galaxies’ specific star formation rates and {M}{{H} {{I}}}/{M}* contrasts with the well-known correlation between {M}{{H} {{I}}}/{M}* and color. We show that dust extinction can explain the H i-color trend, which may arise from the relationship between {M}*, {M}{{H} {{I}}}, and metallicity.

Weight gains, blood parameters, and fecal egg counts when meat-goat kids were finished on alfalfa, red clover, or orchardgrass pastures

USDA-ARS?s Scientific Manuscript database

This experiment was conducted in 2005-2007 to evaluate weight gain, blood parameters associated with forage nutrient-use and anemia from gastrointestinal (GI) parasite infection, and fecal egg counts (FEC) patterns of meat goat kids finished on alfalfa (Medicago sativa L; ALF); red clover (Trifolium...

Transgenic expression of medicago truncatula PR10 and PR5 promoters in alfalfa shows pathogen-induced up-regulation of transgene expression

USDA-ARS?s Scientific Manuscript database

Genetic modification of alfalfa to introduce novel traits requires promoters for controlling gene expression. Promoters that are constitutively activated for expression of genes that enhance disease resistance pose a great energy load on the plant and exert a strong selective pressure on the pathoge...

Deriving Stellar Masses for the ALFALFA α.100 Sample

NASA Astrophysics Data System (ADS)

Hess, Logan; Cornell 2017 Summer REU

2018-01-01

For this project, we explore different methods of deriving the stellar masses of galaxies in the ALFALFA (Arecibo Legacy Fast ALFA) α.100 survey. In particular, we measure the effectiveness of SED (Spectral Energy Distribution) on the sample. SED fitting was preformed by MAGPHYS (Multi-wavelength Analysis of Galaxy Physical Properties), utilizing a wide range of photometry in the UV, optical, and IR bands. Photometry was taken from GALAX GR6/7 (UV), SDSS DR13 (optical), WISE All-Sky (near-IR), and Herschel PACS/SPIRE (far-IR). The efficiency of SED fitting increases with a broader range of photometry, however detection rates varied significantly across the different bands. Using a more “comprehensive” sample of galaxies, the GSWLC-A (GALAX, SDSS, WISE Legacy Catalog All-Sky Survey), we aimed to measure which combination of bands provided the largest sample return with the lowest amount of uncertainty, which could then be used to estimate the masses of the galaxies in the α.100 sample.

Effects of alfalfa silage storage structure and roasting corn on ruminal digestion and microbial CP synthesis in lactating dairy cows

USDA-ARS?s Scientific Manuscript database

The objective of this experiment was to determine the effects of unroasted ground shelled corn (GSC) or roasted GSC (RGSC), when fed with alfalfa, ensiled in bag, bunker, or O2-limiting tower silos on ruminal digestion and microbial protein synthesis in lactating dairy cows. The roasted corn was hea...

The Sinorhizobium meliloti RNA chaperone Hfq influences central carbon metabolism and the symbiotic interaction with alfalfa.

PubMed

Torres-Quesada, Omar; Oruezabal, Roke I; Peregrina, Alexandra; Jofré, Edgardo; Lloret, Javier; Rivilla, Rafael; Toro, Nicolás; Jiménez-Zurdo, José I

2010-03-06

The bacterial Hfq protein is able to interact with diverse RNA molecules, including regulatory small non-coding RNAs (sRNAs), and thus it is recognized as a global post-transcriptional regulator of gene expression. Loss of Hfq has an extensive impact in bacterial physiology which in several animal pathogens influences virulence. Sinorhizobium meliloti is a model soil bacterium known for its ability to establish a beneficial nitrogen-fixing intracellular symbiosis with alfalfa. Despite the predicted general involvement of Hfq in the establishment of successful bacteria-eukaryote interactions, its function in S. meliloti has remained unexplored. Two independent S. meliloti mutants, 2011-3.4 and 1021Deltahfq, were obtained by disruption and deletion of the hfq gene in the wild-type strains 2011 and 1021, respectively, both exhibiting similar growth defects as free-living bacteria. Transcriptomic profiling of 1021Deltahfq revealed a general down-regulation of genes of sugar transporters and some enzymes of the central carbon metabolism, whereas transcripts specifying the uptake and metabolism of nitrogen sources (mainly amino acids) were more abundant than in the wild-type strain. Proteomic analysis of the 2011-3.4 mutant independently confirmed these observations. Symbiotic tests showed that lack of Hfq led to a delayed nodulation, severely compromised bacterial competitiveness on alfalfa roots and impaired normal plant growth. Furthermore, a large proportion of nodules (55%-64%) elicited by the 1021Deltahfq mutant were non-fixing, with scarce content in bacteroids and signs of premature senescence of endosymbiotic bacteria. RT-PCR experiments on RNA from bacteria grown under aerobic and microoxic conditions revealed that Hfq contributes to regulation of nifA and fixK1/K2, the genes controlling nitrogen fixation, although the Hfq-mediated regulation of fixK is only aerobiosis dependent. Finally, we found that some of the recently identified S. meliloti sRNAs co

EBR-II Data Digitization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoon, Su-Jong; Rabiti, Cristian; Sackett, John

2014-08-01

1. Objectives To produce a validation database out of those recorded signals it will be necessary also to identify the documents need to reconstruct the status of reactor at the time of the beginning of the recordings. This should comprehends the core loading specification (assemblies type and location and burn-up) along with this data the assemblies drawings and the core drawings will be identified. The first task of the project will be identify the location of the sensors, with respect the reactor plant layout, and the physical quantities recorded by the Experimental Breeder Reactor-II (EBR-II) data acquisition system. This firstmore » task will allow guiding and prioritizing the selection of drawings needed to numerically reproduce those signals. 1.1 Scopes and Deliverables The deliverables of this project are the list of sensors in EBR-II system, the identification of storing location of those sensors, identification of a core isotopic composition at the moment of the start of system recording. Information of the sensors in EBR-II reactor system was summarized from the EBR-II system design descriptions listed in Section 1.2.« less

Changes in microbial contamination levels and prevalence of foodborne pathogens in alfalfa (Medicago sativa) and rapeseed (Brassica napus) during sprout production in manufacturing plants.

PubMed

Kim, S A; Kim, O M; Rhee, M S

2013-01-01

Samples were taken from three sprout processing plants at five different stages of production (a total of 20 investigations). Quantitative analyses comprised aerobic plate counts (APCs) and the measurement of coliforms and Bacillus cereus levels, whereas qualitative analyses involved assessing the levels of Escherichia coli and major foodborne pathogens (E. coli O157:H7, Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus). The APC for alfalfa seeds (3·71-4·61 log CFU g(-1)) and rapeseed (4·25-5·11 log CFU g(-1)) increased by approximately 3 log CFU g(-1) during sprouting, reaching 7·17-7·61 and 7·33-8·28 log CFU g(-1), respectively, by the final stage of production. Similarly, increasing trends were noted in the level of coliforms (0·58-4·03 log CFU g(-1) at the seed stage, increasing to 5·52-6·99 log CFU g(-1) by the sprout stage). Bacillus cereus was detected in eight alfalfa (40%) and 14 rapeseed (70%) sprouts, and L. monocytogenes was isolated from one pregermination soaked alfalfa seed. A slight reduction in the level of bacterial contamination was noted after washing the sprouts with water prior to storage, indicating that improvements to the current washing protocol, or other efficient intervention methods, may be needed. Taken together, these results suggest that improved hygiene control during production and processing and a more sanitary environment are needed. The present study provides comprehensive information regarding the microbiological safety of seeds and sprouts during manufacturing. The present study investigated the levels of microbial contamination present in alfalfa and rapeseed sprouts by examining the samples taken at different stages of the manufacturing process in three actual plants. The results provide detailed information regarding the levels of seed and sprout contamination during production. The results may be useful to those involved in the sprout industry and/or academic research in terms of developing

Genetic Manipulation of Isoflavone 7-O-Methyltransferase Enhances Biosynthesis of 4′-O-Methylated Isoflavonoid Phytoalexins and Disease Resistance in Alfalfa

PubMed Central

He, Xian-Zhi; Dixon, Richard A.

2000-01-01

4′-O-Methylation of an isoflavonoid intermediate is a key reaction in the biosynthesis of the phytoalexin medicarpin in legumes. However, isoflavone O-methyltransferase (IOMT) from alfalfa converts the isoflavone daidzein to 7-O-methyl daidzein (isoformononetin) in vitro as well as in vivo in unchallenged leaves of transgenic alfalfa ectopically expressing IOMT. In contrast, elicitation of IOMT-overexpressing plants with CuCl2 or infecting these plants with Phoma medicaginis leads to greater accumulation of formononetin (4′-O-methyl daidzein) and medicarpin in the leaves than does elicitation or infection of control plants, and no isoformononetin is detected. Overexpression of IOMT results in increased induction of phenylpropanoid/isoflavonoid pathway gene transcripts after infection but has little effect on basal expression of these genes. IOMT-overexpressing plants display resistance to P. medicaginis. The apparently different regiospecificities of IOMT in vivo and in vitro are discussed in relation to potential metabolic channeling at the entry point into the isoflavonoid pathway. PMID:11006341

De novo amino acid biosynthesis contributes to salmonella enterica growth in Alfalfa seedling exudates.

PubMed

Kwan, Grace; Pisithkul, Tippapha; Amador-Noguez, Daniel; Barak, Jeri

2015-02-01

Salmonella enterica is a member of the plant microbiome. Growth of S. enterica in sprouting-seed exudates is rapid; however, the active metabolic networks essential in this environment are unknown. To examine the metabolic requirements of S. enterica during growth in sprouting-seed exudates, we inoculated alfalfa seeds and identified 305 S. enterica proteins extracted 24 h postinoculation from planktonic cells. Over half the proteins had known metabolic functions, and they are involved in over one-quarter of the known metabolic reactions. Ion and metabolite transport accounted for the majority of detected reactions. Proteins involved in amino acid transport and metabolism were highly represented, suggesting that amino acid metabolic networks may be important for S. enterica growth in association with roots. Amino acid auxotroph growth phenotypes agreed with the proteomic data; auxotrophs in amino acid-biosynthetic pathways that were detected in our screen developed growth defects by 48 h. When the perceived sufficiency of each amino acid was expressed as a ratio of the calculated biomass requirement to the available concentration and compared to growth of each amino acid auxotroph, a correlation between nutrient availability and bacterial growth was found. Furthermore, glutamate transport acted as a fitness factor during S. enterica growth in association with roots. Collectively, these data suggest that S. enterica metabolism is robust in the germinating-alfalfa environment; that single-amino-acid metabolic pathways are important but not essential; and that targeting central metabolic networks, rather than dedicated pathways, may be necessary to achieve dramatic impacts on bacterial growth. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Variable salinity responses of 12 alfalfa genotypes and comparative expression analyses of salt-response genes

PubMed Central

Sandhu, Devinder; Cornacchione, Monica V.; Ferreira, Jorge F. S.; Suarez, Donald L.

2017-01-01

Twelve alfalfa genotypes that were selected for biomass under salinity, differences in Na and Cl concentrations in shoots and K/Na ratio were evaluated in this long-term salinity experiment. The selected plants were cloned to reduce genetic variability within each genotype. Salt tolerance (ST) index of the genotypes ranged from 0.39 to 1. The most salt-tolerant genotypes SISA14-1 (G03) and AZ-90ST (G10), the top performers for biomass, exhibited the least effect on shoot number and height. SISA14-1 (G03) accumulated low Na and Cl under salinity. Most genotypes exhibited a net reduction in shoot Ca, Mg, P, Fe, and Cu, while Mn and Zn increased under salinity. Salinity reduced foliar area and stomatal conductance; while net photosynthetic rate and transpiration were not affected. Interestingly, salinity increased chlorophyll and antioxidant capacity in most genotypes; however neither parameter correlated well to ST index. Salt-tolerant genotypes showed upregulation of the SOS1, SOS2, SOS3, HKT1, AKT1, NHX1, P5CS1, HSP90.7, HSP81.2, HSP71.1, HSPC025, OTS1, SGF29 and SAL1 genes. Gene expression analyses allowed us to classify genotypes based on their ability to regulate different components of the salt tolerance mechanism. Pyramiding different components of the salt tolerance mechanism may lead to superior salt-tolerant alfalfa genotypes. PMID:28225027

Characterization and genetic dissection of resistance to spotted alfalfa aphid (Therioaphis trifolii) in Medicago truncatula

PubMed Central

Kamphuis, Lars G.; Lichtenzveig, Judith; Peng, Kefan; Guo, Su-Min; Klingler, John P.

2013-01-01

Aphids cause significant yield losses in agricultural crops worldwide. Medicago truncatula, a model legume, cultivated pasture species in Australia and close relative of alfalfa (Medicago sativa), was used to study the defence response against Therioaphis trifolii f. maculate [spotted alfalfa aphid (SAA)]. Aphid performance and plant damage were compared among three accessions. A20 is highly susceptible, A17 has moderate resistance, and Jester is strongly resistant. Subsequent analyses using A17 and A20, reciprocal F1s and an A17×A20 recombinant inbred line (RIL) population revealed that this moderate resistance is phloem mediated and involves antibiosis and tolerance but not antixenosis. Electrical penetration graph analysis also identified a novel waveform termed extended potential drop, which occurred following SAA infestation of M. truncatula. Genetic dissection using the RIL population revealed three quantitative trait loci on chromosomes 3, 6, and 7 involved in distinct modes of aphid defence including antibiosis and tolerance. An antibiosis locus resides on linkage group 3 (LG3) and is derived from A17, whereas a plant tolerance and antibiosis locus resides on LG6 and is derived from A20, which exhibits strong temporary tolerance. The loci identified reside in regions harbouring classical resistance genes, and introgression of these loci in current medic cultivars may help provide durable resistance to SAA, while elucidation of their molecular mechanisms may provide valuable insight into other aphid–plant interactions. PMID:24058162

Comparison of bioavailable vanadium in alfalfa rhizosphere soil extracted by an improved BCR procedure and EDTA, HCl, and NaNO₃ single extractions in a pot experiment with V-Cd treatments.

PubMed

Yang, Jie; Teng, Yanguo; Zuo, Rui; Song, Liuting

2015-06-01

The BCR sequential extraction procedure was compared with EDTA, HCl, and NaNO3 single extractions for evaluating vanadium bioavailability in alfalfa rhizosphere soil. The amounts of vanadium extracted by these methods were in the following order: BCR (bioavailable V) > EDTA ≈ HCl > NaNO3. Both correlation analysis and stepwise regression were adopted to illustrate the extractable vanadium between different reagents. The correlation coefficients between extracted vanadium and the vanadium contents in alfalfa roots were R NaNO3 = 0.948, R HCl = 0.902, R EDTA = 0.816, and R bioavailable V = 0.819. The stepwise multiple regression equation of the NaNO3 extraction was the most significant at a 95 % confidence interval. The influence of pH, total organic carbon, and cadmium content of soil to vanadium bioavailability were not definite. In summary, both the BCR sequential extraction and the single extraction methods were valid approaches for predicting vanadium bioavailability in alfalfa rhizosphere soil, especially the single extractions.

Transgenic alfalfa (Medicago sativa) with increased sucrose phosphate synthase activity shows enhanced growth when grown under N2-fixing conditions.

PubMed

Gebril, Sayed; Seger, Mark; Villanueva, Fabiola Muro; Ortega, Jose Luis; Bagga, Suman; Sengupta-Gopalan, Champa

2015-10-01

Overexpression of SPS in alfalfa is accompanied by early flowering, increased plant growth and an increase in elemental N and protein content when grown under N2-fixing conditions. Sucrose phosphate synthase (SPS; EC 2.3.1.14) is the key enzyme in the synthesis of sucrose in plants. The outcome of overexpression of SPS in different plants using transgenic approaches has been quite varied, but the general consensus is that increased SPS activity is associated with the production of new sinks and increased sink strength. In legumes, the root nodule is a strong C sink and in this study our objective was to see how increasing SPS activity in a legume would affect nodule number and function. Here we have transformed alfalfa (Medicago sativa, cv. Regen SY), with a maize SPS gene driven by the constitutive CaMV35S promoter. Our results showed that overexpression of SPS in alfalfa, is accompanied by an increase in nodule number and mass and an overall increase in nitrogenase activity at the whole plant level. The nodules exhibited an increase in the level of key enzymes contributing to N assimilation including glutamine synthetase and asparagine synthetase. Moreover, the stems of the transformants showed higher level of the transport amino acids, Asx, indicating increased export of N from the nodules. The transformants exhibited a dramatic increase in growth both of the shoots and roots, and earlier flowering time, leading to increased yields. Moreover, the transformants showed an increase in elemental N and protein content. The overall conclusion is that increased SPS activity improves the N status and plant performance, suggesting that the availability of more C in the form of sucrose enhances N acquisition and assimilation in the nodules.

Human-centric predictive model of task difficulty for human-in-the-loop control tasks

PubMed Central

Majewicz Fey, Ann

2018-01-01

Quantitatively measuring the difficulty of a manipulation task in human-in-the-loop control systems is ill-defined. Currently, systems are typically evaluated through task-specific performance measures and post-experiment user surveys; however, these methods do not capture the real-time experience of human users. In this study, we propose to analyze and predict the difficulty of a bivariate pointing task, with a haptic device interface, using human-centric measurement data in terms of cognition, physical effort, and motion kinematics. Noninvasive sensors were used to record the multimodal response of human user for 14 subjects performing the task. A data-driven approach for predicting task difficulty was implemented based on several task-independent metrics. We compare four possible models for predicting task difficulty to evaluated the roles of the various types of metrics, including: (I) a movement time model, (II) a fusion model using both physiological and kinematic metrics, (III) a model only with kinematic metrics, and (IV) a model only with physiological metrics. The results show significant correlation between task difficulty and the user sensorimotor response. The fusion model, integrating user physiology and motion kinematics, provided the best estimate of task difficulty (R2 = 0.927), followed by a model using only kinematic metrics (R2 = 0.921). Both models were better predictors of task difficulty than the movement time model (R2 = 0.847), derived from Fitt’s law, a well studied difficulty model for human psychomotor control. PMID:29621301

Cognitive-motor dual-task ability of athletes with and without intellectual impairment.

PubMed

Van Biesen, Debbie; Jacobs, Lore; McCulloch, Katina; Janssens, Luc; Vanlandewijck, Yves C

2018-03-01

Cognition is important in many sports, for example, making split-second-decisions under pressure, or memorising complex movement sequences. The dual-task (DT) paradigm is an ecologically valid approach for the assessment of cognitive function in conjunction with motor demands. This study aimed to determine the impact of impaired intelligence on DT performance. The motor task required balancing on one leg on a beam, and the cognitive task was a multiple-object-tracking (MOT) task assessing dynamic visual-search capacity. The sample included 206 well-trained athletes with and without intellectual impairment (II), matched for sport, age and training volume (140 males, 66 females, M age = 23.2 ± 4.1 years, M training experience = 12.3 ± 5.7 years). In the single-task condition, II-athletes showed reduced balance control (F = 55.9, P < .001, η 2  = .23) and reduced MOT (F = 86.3, P < .001, η 2  = .32) compared to the control group. A mixed-model ANCOVA revealed significant differences in DT performance for the balance and the MOT task between both groups. The DT costs were significantly larger for the II-athletes (-8.28% versus -1.34% for MOT and -33.13% versus -12.89% for balance). The assessment of MOT in a DT paradigm provided insight in how impaired intelligence constrains the ability of II-athletes to successfully perform at the highest levels in the complex and dynamical sport-environment.

Effect of feeding alfalfa hay or Tifton 85 bermudagrass haylage with or without a cellulase enzyme on performance of Holstein cows.

PubMed

Bernard, J K; Castro, J J; Mullis, N A; Adesogan, A T; West, J W; Morantes, G

2010-11-01

Forty-four lactating Holstein cows (173±30 DIM, 42.5±6.8 kg of milk, 4.03±0.69% fat, 674±78 kg of body weight) were used in an 8-wk, completely randomized trial with a 2 × 2 factorial arrangement of treatments to determine the effect of forage source and supplemental cellulase enzyme on performance. Treatments included 2 forage combinations (corn silage plus 12.2% dry matter, DM, from either alfalfa hay or Tifton 85 bermudagrass haylage) with or without a commercial cellulase enzyme applied to the total mixed ration at the rate of 4 g/head per day (Promote N.E.T.-L, Cargill Animal Nutrition, Minneapolis, MN). Experimental diets were formulated to provide similar concentrations of protein (16.5% of DM), energy (1.63 Mcal of net energy for lactation/kg of DM), and neutral detergent fiber (41.7% of DM) and were fed once daily as a total mixed ration behind Calan doors for ad libitum intake. The cellulase enzyme provided 1,200 cellulase units of activity/g of product and was applied to the total mixed ration and allowed to mix for 5min before feeding. Before beginning the trial, all cows were trained to use Calan (American Calan, Northwood, NH) doors and then fed the alfalfa hay-based diet for 2 wk. Data collected during wk 2 were used as a covariate in the statistical analysis. At the beginning of the 6-wk experimental period, cows were assigned randomly to 1 of the 4 experimental diets. No interactions were observed between forage and enzyme for any measures. Daily DM intake; milk yield; concentrations of milk fat, true protein, lactose, and solids not fat; energy-corrected milk yield; and dairy efficiency were not different among alfalfa or Tifton 85 bermudagrass rations with or without cellulase enzyme supplementation. The results of this trial indicate that Tifton 85 bermudagrass haylage can replace alfalfa hay in diets fed to high-producing, lactating dairy cows without depressing DM intake or milk yield when rations are balanced for NDF. Although

Commercial Vehicle Architecture Systems Study, Volume II: Task Reports

DOT National Transportation Integrated Search

1993-10-01

WEIGH-IN-MOTION OR WIM, DRIVER PERFORMANCE MONITORING, ELECTRONIC DATA INTERCHANGE OR EDI, COMMERCIAL VEHICLE OPERATIONS OR CVO : THIS REPORT DETAILS PROGRESS TO DATE ON A SET OF TASKS BEING PERFORMED BY SANDIA NATIONAL LABORATORIES (SNL) FOR THE ...

Presence and correlation of some enteric indicator bacteria, diarrheagenic Escherichia coli pathotypes, and Salmonella serotypes in alfalfa sprouts from local retail markets in Pachuca, Mexico.

PubMed

Rangel-Vargas, Esmeralda; Gómez-Aldapa, Carlos A; Torres-Vitela, M Del Refugio; Villarruel-López, Angélica; Gordillo-Martínez, Alberto J; Castro-Rosas, Javier

2015-03-01

Data on the presence of diarrheagenic Escherichia coli pathotypes (DEPs) in alfalfa sprouts and correlations between the presence of coliform bacteria (CB), fecal coliforms (FC), E. coli, DEPs, and Salmonella in alfalfa sprouts are not available. The presence of and correlations between CB, FC, E. coli, DEPs, and Salmonella in alfalfa sprouts were determined. One hundred sprout samples were collected from retail markets in Pachuca, Hidalgo State, Mexico. The presence of indicator bacteria and Salmonella was determined using conventional culture procedures. DEPs were identified using two multiplex PCR procedures. One hundred percent of samples were positive for CB, 90% for FC, 84% for E. coli, 10% for DEPs, and 4% for Salmonella. The populations of CB ranged from 6.2 up to 8.6 log CFU/g. The FC and E. coli concentrations were between , 3 and 1,100 most probable number (MPN)/g. The DEPs identified included enterotoxigenic E. coli (ETEC; 2%), enteropathogenic E. coli (EPEC; 3%), and Shiga toxin-producing E. coli (STEC; 5%). No E. coli O157:H7 strains were detected in any STEC-positive samples. In samples positive for DEPs, the concentrations ranged from 210 to 240 MPN/g for ETEC, 28 to 1,100 MPN/g for EPEC, and 3.6 to 460 MPN/g for STEC. The Salmonella isolates identified included Salmonella enterica serotype Typhimurium in three samples and Salmonella enterica serotype Enteritidis in one. STEC and Salmonella Typhimurium were identified together in one sample. Positive correlations were observed between FC and E. coli, between FC and DEPs, and between E. coli and DEPs. Negative correlations occurred between CB and DEPs and between CB and Salmonella. Neither FC nor E. coli correlated with Salmonella in the sprout samples. To our knowledge, this is the first report of ETEC, EPEC, and STEC isolated from alfalfa sprouts and the first report of correlations between different indicator groups versus DEPs and Salmonella.

Neurophysiological signature of effective anticipatory task-set control: a task-switching investigation.

PubMed

Lavric, Aureliu; Mizon, Guy A; Monsell, Stephen

2008-09-01

Changing between cognitive tasks requires a reorganization of cognitive processes. Behavioural evidence suggests this can occur in advance of the stimulus. However, the existence or detectability of an anticipatory task-set reconfiguration process remains controversial, in part because several neuroimaging studies have not detected extra brain activity during preparation for a task switch relative to a task repeat. In contrast, electrophysiological studies have identified potential correlates of preparation for a task switch, but their interpretation is hindered by the scarcity of evidence on their relationship to performance. We aimed to: (i) identify the brain potential(s) reflecting effective preparation for a task-switch in a task-cuing paradigm that shows clear behavioural evidence for advance preparation, and (ii) characterize this activity by means of temporal segmentation and source analysis. Our results show that when advance preparation was effective (as indicated by fast responses), a protracted switch-related component, manifesting itself as widespread posterior positivity and concurrent right anterior negativity, preceded stimulus onset for approximately 300 ms, with sources primarily in the left lateral frontal, right inferior frontal and temporal cortices. When advance preparation was ineffective (as implied by slow responses), or made impossible by a short cue-stimulus interval (CSI), a similar component, with lateral prefrontal generators, peaked approximately 300 ms poststimulus. The protracted prestimulus component (which we show to be distinct from P3 or contingent negative variation, CNV) also correlated over subjects with a behavioural measure of preparation. Furthermore, its differential lateralization for word and picture cues was consistent with a role for verbal self-instruction in preparatory task-set reconfiguration.

Complete genome sequence and integrated protein localization and interaction map for alfalfa dwarf virus, which combines properties of both cytoplasmic and nuclear plant rhabdoviruses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bejerman, Nicolás, E-mail: n.bejerman@uq.edu.au; Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, QLD 4072; Giolitti, Fabián

Summary: We have determined the full-length 14,491-nucleotide genome sequence of a new plant rhabdovirus, alfalfa dwarf virus (ADV). Seven open reading frames (ORFs) were identified in the antigenomic orientation of the negative-sense, single-stranded viral RNA, in the order 3′-N-P-P3-M-G-P6-L-5′. The ORFs are separated by conserved intergenic regions and the genome coding region is flanked by complementary 3′ leader and 5′ trailer sequences. Phylogenetic analysis of the nucleoprotein amino acid sequence indicated that this alfalfa-infecting rhabdovirus is related to viruses in the genus Cytorhabdovirus. When transiently expressed as GFP fusions in Nicotiana benthamiana leaves, most ADV proteins accumulated in the cellmore » periphery, but unexpectedly P protein was localized exclusively in the nucleus. ADV P protein was shown to have a homotypic, and heterotypic nuclear interactions with N, P3 and M proteins by bimolecular fluorescence complementation. ADV appears unique in that it combines properties of both cytoplasmic and nuclear plant rhabdoviruses. - Highlights: • The complete genome of alfalfa dwarf virus is obtained. • An integrated localization and interaction map for ADV is determined. • ADV has a genome sequence similarity and evolutionary links with cytorhabdoviruses. • ADV protein localization and interaction data show an association with the nucleus. • ADV combines properties of both cytoplasmic and nuclear plant rhabdoviruses.« less

Evaluation of aerated steam treatment of alfalfa and mung bean seeds to eliminate high levels of Escherichia coli O157:H7 and O178:H12, Salmonella enterica, and Listeria monocytogenes.

PubMed

Studer, Patrick; Heller, Werner E; Hummerjohann, Jörg; Drissner, David

2013-08-01

Sprouts contaminated with human pathogens are able to cause food-borne diseases due to the favorable growth conditions for bacteria during germination and because of minimal processing steps prior to consumption. We have investigated the potential of hot humid air, i.e., aerated steam, to treat alfalfa and mung bean seeds which have been artificially contaminated with Escherichia coli O157:H7, Salmonella enterica subsp. enterica serovar Weltevreden, and Listeria monocytogenes Scott A. In addition, a recently collected E. coli O178:H12 isolate, characterized by a reduced heat sensitivity, was exposed to the treatment described. Populations of E. coli O157:H7 and S. enterica on alfalfa and mung bean seeds could be completely eliminated by a 300-s treatment with steam at 70 ± 1°C as revealed by enrichment studies. L. monocytogenes and E. coli O178:H12 could not be completely eliminated from artificially inoculated seeds. However, bacterial populations were reduced by more than 5 log CFU/g on alfalfa and by more than 4 log CFU/g on mung bean seeds. The germination rate of mung beans was not affected by the 300-s treatment compared to the germination rate of untreated seeds whereas that of alfalfa seeds was significantly lower by 11.9%. This chemical-free method is an effective alternative to the 20,000-ppm hypochlorite treatment presently recommended by the U.S. Food and Drug Administration (FDA).

Evaluation of Aerated Steam Treatment of Alfalfa and Mung Bean Seeds To Eliminate High Levels of Escherichia coli O157:H7 and O178:H12, Salmonella enterica, and Listeria monocytogenes

PubMed Central

Studer, Patrick; Heller, Werner E.; Hummerjohann, Jörg

2013-01-01

Sprouts contaminated with human pathogens are able to cause food-borne diseases due to the favorable growth conditions for bacteria during germination and because of minimal processing steps prior to consumption. We have investigated the potential of hot humid air, i.e., aerated steam, to treat alfalfa and mung bean seeds which have been artificially contaminated with Escherichia coli O157:H7, Salmonella enterica subsp. enterica serovar Weltevreden, and Listeria monocytogenes Scott A. In addition, a recently collected E. coli O178:H12 isolate, characterized by a reduced heat sensitivity, was exposed to the treatment described. Populations of E. coli O157:H7 and S. enterica on alfalfa and mung bean seeds could be completely eliminated by a 300-s treatment with steam at 70 ± 1°C as revealed by enrichment studies. L. monocytogenes and E. coli O178:H12 could not be completely eliminated from artificially inoculated seeds. However, bacterial populations were reduced by more than 5 log CFU/g on alfalfa and by more than 4 log CFU/g on mung bean seeds. The germination rate of mung beans was not affected by the 300-s treatment compared to the germination rate of untreated seeds whereas that of alfalfa seeds was significantly lower by 11.9%. This chemical-free method is an effective alternative to the 20,000-ppm hypochlorite treatment presently recommended by the U.S. Food and Drug Administration (FDA). PMID:23709507

Rumen clearance rates in relation to the occurrence of alfalfa bloat in cattle. 1. Passage of water-soluble markers.

PubMed

Majak, W; Hall, J W; Rode, L M; Kalnin, C M

1986-06-01

Ruminal chlorophyll and rates of passage of two water-soluble markers were simultaneously determined in cattle with different susceptibilities to alfalfa bloat. The markers showed a slower rate of passage from the rumens of more susceptible cattle where the average half-lives for cobalt-ethylenediaminetetraacetic acid and chromium-ethylenediaminetetraacetic acid were 12 to 17 h. Average half-life of the markers was 8 h in the rumens of the less susceptible animals. In agreement, chloroplast particles in the liquid phase of rumen contents showed greater accumulation in animals susceptible to bloat, but many more observations were required to detect differences in chlorophyll among animals. This was partly due to the unhomogeneous dispersion of chloroplast fragments in the reticulorumen compared with the uniform distribution of the inert markers. Differences in rumen volumes (estimated from the quantity of marker administered and its initial concentration) were detected among animals, but these did not show a relationship to bloat susceptibility. In vitro studies indicated that alfalfa chloroplast particles were not readily degraded by rumen microorganisms. Our results support earlier conclusions on slower rates of salivation for cattle that bloat compared with those that do not.

Effects of alfalfa flavonoids extract on the microbial flora of dairy cow rumen.

PubMed

Zhan, Jinshun; Liu, Mingmei; Wu, Caixia; Su, Xiaoshuang; Zhan, Kang; Zhao, Guo Qi

2017-09-01

The effect of flavonoids from alfalfa on the microbial flora was determined using molecular techniques of 16S ribosome deoxyribonucleic acid (rDNA) analysis. Four primiparous Holstein heifers fitted with ruminal cannulas were used in a 4×4 Latin square design and fed a total mixed ration to which alfalfa flavonoids extract (AFE) was added at the rates of 0 (A, control), 20 (B), 60 (C), or 100 (D) mg per kg of heifer BW. The number of operational taxonomic units in heifers given higher levels of flavonoid extract (C and D) was higher than for the two other treatments. The Shannon, Ace, and Chao indices for treatment C were significantly higher than for the other treatments (p<0.05). The number of phyla and genera increased linearly with increasing dietary supplementation of AFE (p<0.05). The principal co-ordinates analysis plot showed substantial differences in the microbial flora for the four treatments. The microbial flora in treatment A was similar to that in B, C, and D were similar by the weighted analysis. The richness of Tenericutes at the phylum level tended to increase with increasing AFE (p = 0.10). The proportion of Euryarchaeota at the phylum level increased linearly, whereas the proportion of Fusobacteria decreased linearly with increasing AFE supplementation (p = 0.04). The percentage of Mogibacterium , Pyramidobacter , and Asteroleplasma at the genus level decreased linearly with increasing AFE (p<0.05). The abundance of Spirochaeta , Succinivibrio , and Suttonella at the genus level tended to decrease linearly with increasing AFE (0.05

Effects of feeding alfalfa stemlage or wheat straw for dietary energy dilution on growth performance and sorting behaviors of holstein dairy heifers

USDA-ARS?s Scientific Manuscript database

Feeding high-quality forage diets may lead to excessive weight gains and over-conditioning for pregnant Holstein heifers. Restriction of energy density and dry matter intake (DMI) by heifers by using low-energy forages, such as straw, is a good approach for controlling this problem. Alfalfa stems co...

The ALFALFA H I mass function: a dichotomy in the low-mass slope and a locally suppressed `knee' mass

NASA Astrophysics Data System (ADS)

Jones, Michael G.; Haynes, Martha P.; Giovanelli, Riccardo; Moorman, Crystal

2018-06-01

We present the most precise measurement of the z = 0 H I mass function (HIMF) to date based on the final catalogue of the ALFALFA (Arecibo Legacy Fast ALFA) blind H I survey of the nearby Universe. The Schechter function fit has a `knee' mass log (M_{*} h2_{70}/M_{⊙}) = 9.94 ± 0.01 ± 0.05, a low-mass slope parameter α = -1.25 ± 0.02 ± 0.1, and a normalization φ _{*} = (4.5 ± 0.2 ± 0.8) × 10^{-3} h3_{70} Mpc^{-3 dex^{-1}}, with both random and systematic uncertainties as quoted. Together these give an estimate of the H I content of the z = 0 Universe as Ω _{H I} = (3.9 ± 0.1 ± 0.6) × 10^{-4} h^{-1}_{70} (corrected for H I self-absorption). Our analysis of the uncertainties indicates that the `knee' mass is a cosmologically fair measurement of the z = 0 value, with its largest uncertainty originating from the absolute flux calibration, but that the low-mass slope is only representative of the local Universe. We also explore large-scale trends in α and M* across the ALFALFA volume. Unlike with the 40 per cent sample, there is now sufficient coverage in both of the survey fields to make an independent determination of the HIMF in each. We find a large discrepancy in the low-mass slope (Δα = 0.14 ± 0.03) between the two regions, and argue that this is likely caused by the presence of a deep void in one field and the Virgo cluster in the other. Furthermore, we find that the value of the `knee' mass within the Local Volume appears to be suppressed by 0.18 ± 0.04 dex compared to the global ALFALFA value, which explains the lower value measured by the shallower H I Parkes All Sky Survey (HIPASS). We discuss possible explanations and interpretations of these results and how they can be expanded on with future surveys.

Efficacy of ozone in killing Listeria monocytogenes on alfalfa seeds and sprouts and effects on sensory quality of sprouts.

PubMed

Wade, W N; Scouten, A J; McWatters, K H; Wick, R L; Demirci, A; Fett, W F; Beuchat, L R

2003-01-01

A study was done to determine the efficacy of aqueous ozone treatment in killing Listeria monocytogenes on inoculated alfalfa seeds and sprouts. Reductions in populations of naturally occurring aerobic microorganisms on sprouts and changes in the sensory quality of sprouts were also determined. The treatment (10 or 20 min) of seeds in water (4 degrees C) containing an initial concentration of 21.8 +/- 0.1 microg/ml of ozone failed to cause a significant (P < or = 0.05) reduction in populations of L. monocytogenes. The continuous sparging of seeds with ozonated water (initial ozone concentration of 21.3 +/- 0.2 microg/ml) for 20 min significantly reduced the population by 1.48 log10 CFU/g. The treatment (2 min) of inoculated alfalfa sprouts with water containing 5.0 +/- 0.5, 9.0 +/- 0.5, or 23.2 +/- 1.6 microg/ml of ozone resulted in significant (P < or = 0.05) reductions of 0.78, 0.81, and 0.91 log10 CFU/g, respectively, compared to populations detected on sprouts treated with water. Treatments (2 min) with up to 23.3 +/- 1.6 microg/ml of ozone did not significantly (P > 0.05) reduce populations of aerobic naturally occurring microorganisms. The continuous sparging of sprouts with ozonated water for 5 to 20 min caused significant reductions in L. monocytogenes and natural microbiota compared to soaking in water (control) but did not enhance the lethality compared to the sprouts not treated with continuous sparging. The treatment of sprouts with ozonated water (20.0 microg/ml) for 5 or 10 min caused a significant deterioration in the sensory quality during subsequent storage at 4 degrees C for 7 to 11 days. Scanning electron microscopy of uninoculated alfalfa seeds and sprouts showed physical damage, fungal and bacterial growth, and biofilm formation that provide evidence of factors contributing to the difficulty of killing microorganisms by treatment with ozone and other sanitizers.

Effects of varying dietary ratios of corn silage to alfalfa silage on digestion of neutral detergent fiber in lactating dairy cows.

PubMed

Lopes, F; Cook, D E; Combs, D K

2015-09-01

An in vivo study was performed to test an in vitro procedure and model that predicts total-tract neutral detergent fiber (NDF) digestibility for lactating dairy cattle. Corn silage (CS) and alfalfa silage (AS) were used as forages for this study. These forages had similar NDF composition, but fiber in the CS contained less indigestible NDF compared with AS (35.5 and 47.8% of indigestible NDF, respectively). The in vitro method estimated rate of digestion of alfalfa potentially digestible NDF to be approximately 2 times faster than CS fiber (6.11 and 3.21%/h, respectively). Four diets were formulated containing different proportions of CS to AS: 100CS:0AS, 67CS:33AS, 33CS:67AS, and 0CS:100AS, as percentage of diet DM basis. The objective was to construct diets that contained approximately similar levels of NDF but with different pool sizes and rates of digestion of potentially digestible NDF. Diets were fed to 8 ruminally cannulated, multiparous, lactating dairy cows in a replicated 4×4 Latin square with 21-d periods. Total-tract fiber digestibility and fiber digestion kinetic parameters observed in vivo were compared with the values predicted by the in vitro assay and model. Total-tract NDF digestibility coefficients were similar (41.8 and 40.6% of total NDF) for the in vitro and in vivo methods, respectively. As the proportion of dietary alfalfa increased, the digestibility of NDF increased. The rate of digestion of potentially digestible NDF predicted from the in vitro assay was also similar to what was observed in vivo. Results suggest that the in vitro total-tract NDF digestibility model could be used to predict rate of fiber digestion and NDF digestibility for lactating dairy cattle. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effects of natural and simulated rainfall on indicators of ensilability and nutritive value for wilting alfalfa forages sampled before preservation as silage.

PubMed

Coblentz, W K; Muck, R E

2012-11-01

The frustrations of forage producers attempting to conserve high-quality alfalfa (Medicago sativa L.) silage during periods of unstable or inclement weather are widely known. Our objectives for this series of studies were to (1) assess indicators of ensilability, such as pH, buffering capacity, water-soluble carbohydrates (WSC), and starch for wilting alfalfa forages receiving no rainfall or damaged by simulated or natural rainfall events; (2) use these data as inputs to calculate the threshold moisture concentration that would prohibit a clostridially dominated fermentation; and (3) further evaluate the effects of rain damage or no rain damage on measures of forage nutritive value. Rainfall events were applied to wilting forages by both simulated and natural methods over multiple studies distributed across 4 independent forage harvests. Generally, simulated rainfall was applied to alfalfa under controlled conditions in which forages were relatively wet at the time of application, and subsequently were dried to final moisture endpoints under near ideal conditions within a constant temperature/humidity environmental chamber, thereby limiting postwetting wilting time to ≤21 h. As a result, indicators of ensilability, as well as measures of nutritive value, changed only marginally as a result of treatment. Consistently, reductions in concentrations of WSC and starch occurred, but changes in WSC were relatively modest, and postwetting concentrations of WSC may have been buoyed by hydrolysis of starch. When forages were subjected to natural rainfall events followed by prolonged exposure under field conditions, indicators of ensilability were much less desirable. In one study in which alfalfa received 49.3mm of natural rainfall over a prolonged (8-d) field-exposure period, fresh pH increased from 6.48 to 7.43 within all forages exposed to these extended, moist wilting conditions. Furthermore, sharp reductions were observed in buffering capacity (410 vs. 337 meq/kg of

The Sinorhizobium meliloti RNA chaperone Hfq influences central carbon metabolism and the symbiotic interaction with alfalfa

PubMed Central

2010-01-01

Background The bacterial Hfq protein is able to interact with diverse RNA molecules, including regulatory small non-coding RNAs (sRNAs), and thus it is recognized as a global post-transcriptional regulator of gene expression. Loss of Hfq has an extensive impact in bacterial physiology which in several animal pathogens influences virulence. Sinorhizobium meliloti is a model soil bacterium known for its ability to establish a beneficial nitrogen-fixing intracellular symbiosis with alfalfa. Despite the predicted general involvement of Hfq in the establishment of successful bacteria-eukaryote interactions, its function in S. meliloti has remained unexplored. Results Two independent S. meliloti mutants, 2011-3.4 and 1021Δhfq, were obtained by disruption and deletion of the hfq gene in the wild-type strains 2011 and 1021, respectively, both exhibiting similar growth defects as free-living bacteria. Transcriptomic profiling of 1021Δhfq revealed a general down-regulation of genes of sugar transporters and some enzymes of the central carbon metabolism, whereas transcripts specifying the uptake and metabolism of nitrogen sources (mainly amino acids) were more abundant than in the wild-type strain. Proteomic analysis of the 2011-3.4 mutant independently confirmed these observations. Symbiotic tests showed that lack of Hfq led to a delayed nodulation, severely compromised bacterial competitiveness on alfalfa roots and impaired normal plant growth. Furthermore, a large proportion of nodules (55%-64%) elicited by the 1021Δhfq mutant were non-fixing, with scarce content in bacteroids and signs of premature senescence of endosymbiotic bacteria. RT-PCR experiments on RNA from bacteria grown under aerobic and microoxic conditions revealed that Hfq contributes to regulation of nifA and fixK1/K2, the genes controlling nitrogen fixation, although the Hfq-mediated regulation of fixK is only aerobiosis dependent. Finally, we found that some of the recently identified S. meliloti s

Characterization of two novel cold-inducible K3 dehydrin genes from alfalfa (Medicago sativa spp. sativa L.).

PubMed

Dubé, Marie-Pier; Castonguay, Yves; Cloutier, Jean; Michaud, Josée; Bertrand, Annick

2013-03-01

Dehydrin defines a complex family of intrinsically disordered proteins with potential adaptive value with regard to freeze-induced cell dehydration. Search within an expressed sequence tags library from cDNAs of cold-acclimated crowns of alfalfa (Medicago sativa spp. sativa L.) identified transcripts putatively encoding K(3)-type dehydrins. Analysis of full-length coding sequences unveiled two highly homologous sequence variants, K(3)-A and K(3)-B. An increase in the frequency of genotypes yielding positive genomic amplification of the K(3)-dehydrin variants in response to selection for superior tolerance to freezing and the induction of their expression at low temperature strongly support a link with cold adaptation. The presence of multiple allelic forms within single genotypes and independent segregation indicate that the two K(3) dehydrin variants are encoded by distinct genes located at unlinked loci. The co-inheritance of the K(3)-A dehydrin with a Y(2)K(4) dehydrin restriction fragment length polymorphism with a demonstrated impact on freezing tolerance suggests the presence of a genome domain where these functionally related genes are located. These results provide additional evidence that dehydrin play important roles with regard to tolerance to subfreezing temperatures. They also underscore the value of recurrent selection to help identify variants within a large multigene family in allopolyploid species like alfalfa.

Radar response to vegetation. II - 8-18 GHz band

NASA Technical Reports Server (NTRS)

Ulaby, F. T.; Bush, T. F.; Batlivala, P. P.

1975-01-01

The results of experimental studies on the backscattering properties of corn, milo, soybeans, and alfalfa are presented. The measurements were made during the summer of 1973 over the 8-18 GHz frequency band. The data indicate that soil moisture estimation is best accomplished at incidence angles near nadir with lower frequencies while crop discrimination is best accomplished using two frequencies at incidence angles ranging from 30 deg to 65 deg. It is also shown that temporal plant morphology variations can cause extreme variations in the values of the scattering coefficients. These morphological changes can be caused by growth, heavy rain, and in the case of alfalfa, harvesting.

ETS Matched Pictures Language Comprehension Task I and II; Technical Report 5. Disadvantaged Children and Their First School Experiences. ETS-Head Start Longitudinal Study. Technical Report Series.

ERIC Educational Resources Information Center

Meissner, Judith A.; And Others

The ETS Matched Pictures test was used in the longitudinal study to measure children's comprehension of certain grammatical features, such as past and future tenses, negation and prepositions. The task materials for both I and II consist of a set of cards, with each card having a pair of black and white pictures. Both pictures in a pair contain…

Electronic toll collection interoperability study in Brazil. Task 2 : economic and financial analysis and Task 3 : environmental/societal analysis

DOT National Transportation Integrated Search

1998-05-01

This report, conducted by Parsons Bricknerhoff International, was funded by the U.S. Trade and Development Agency. The report examines the potential for developing electronic toll collection systems in Brazil. This is Volume II and it contains "Task ...

Evaluation of Salmonella enteritidis in molting hens after administration of an experimental chlorate product (for nine days) in the drinking water and feeding an alfalfa molt diet.

PubMed

McReynolds, J; Kubena, L; Byrd, J; Anderson, R; Ricke, S; Nisbet, D

2005-08-01

The method most commonly used to induce molting and stimulate multiple egg-laying cycles in laying hens for commercial egg production is to fast the hens. Unfortunately, increased risk of Salmonella enteritidis (SE) infection may result from the use of this method. Methods to stimulate multiple egg-laying cycles without increasing the risk of SE infection are needed. Hens over 50 wk of age were divided into 12 groups of 11 hens each and placed in individual laying cages. One week prior to dietary changes, hens were placed on an 8-h light and 16-h dark photoperiod that continued for the 9-d molt. All hens were challenged orally with 10(6) cfu of SE on the fourth day of the molt. Treatments were nonfed hens with distilled water (NFD), nonfed hens with the experimental chlorate product (ECP, which provided 15 mM chlorate ion) water (NFECP), alfalfa diets with distilled water (ALD), and alfalfa diets with ECP water (ALECP). In the NFD hens, 67% (log10 2.74) of the crops and 94% (log10 5.62) of the ceca were colonized, whereas for the NFECP hens significant reductions to 22% (log10 1.05) of the crops and 61% (log10 2.44) of the ceca were observed. In the ALD hens, 61% (log10 2.52) of the crops and 94% (log10 4.06) of the ceca were colonized. In the ALECP hens, highly significant reductions to 11% (log10 1.26) of the crops and 39% (log10 1.12) of the ceca were observed. When compared with the NFD hens, significant reductions in SE invasion of the ovary, liver, and spleen occurred in all other treatments, except the ovary in the ALD hens. The low alfalfa intake is probably a factor in our lowered protection against SE when compared with previous results. For several parameters, these results suggest that ECP or the combination of ECP and alfalfa may be a useful tool to reduce the risk of SE during an induced molt.

Co-transforming bar and CsALDH Genes Enhanced Resistance to Herbicide and Drought and Salt Stress in Transgenic Alfalfa (Medicago sativa L.)

PubMed Central

Duan, Zhen; Zhang, Daiyu; Zhang, Jianquan; Di, Hongyan; Wu, Fan; Hu, Xiaowen; Meng, Xuanchen; Luo, Kai; Zhang, Jiyu; Wang, Yanrong

2015-01-01

Drought and high salinity are two major abiotic factors that restrict the productivity of alfalfa. By application of the Agrobacterium-mediated transformation method, an oxidative responsive gene, CsALDH12A1, from the desert grass Cleistogenes songorica together with the bar gene associated with herbicide resistance, were co-transformed into alfalfa (Medicago sativa L.). From the all 90 transformants, 16 were positive as screened by spraying 1 mL L-1 10% Basta solution and molecularly diagnosis using PCR. Real-time PCR analysis indicated that drought and salt stress induced high CsALDH expression in the leaves of the transgenic plants. The CsALDH expression levels under drought (15 d) and salt stress (200 mM NaCl) were 6.11 and 6.87 times higher than in the control plants, respectively. In comparison to the WT plants, no abnormal phenotypes were observed among the transgenic plants, which showed significant enhancement of tolerance to 15 d of drought and 10 d of salinity treatment. Evaluation of the physiological and biochemical indices during drought and salt stress of the transgenic plants revealed relatively lower Na+ content and higher K+ content in the leaves relative to the WT plants, a reduction of toxic on effects and maintenance of osmotic adjustment. In addition, the transgenic plants could maintain a higher relative water content level, higher shoot biomass, fewer changes in the photosystem, decreased membrane injury, and a lower level of osmotic stress. These results indicate that the co-expression of the introduced bar and CsALDH genes enhanced the herbicide, drought and salt tolerance of alfalfa and therefore can potentially be used as a novel genetic resource for the future breeding programs to develop new cultivars. PMID:26734025

THE ALFALFA H I ABSORPTION PILOT SURVEY: A WIDE-AREA BLIND DAMPED Ly{alpha} SYSTEM SURVEY OF THE LOCAL UNIVERSE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Darling, Jeremy; Macdonald, Erin P.; Haynes, Martha P.

2011-11-20

We present the results of a pilot survey for neutral hydrogen (H I) 21 cm absorption in the Arecibo Legacy Fast Arecibo L-Band Feed Array (ALFALFA) Survey. This project is a wide-area 'blind' search for H I absorption in the local universe, spanning -650 km s{sup -1} < cz < 17, 500 km s{sup -1} and covering 517.0 deg{sup 2} (7% of the full ALFALFA survey). The survey is sensitive to H I absorption lines stronger than 7.7 mJy (8983 radio sources) and is 90% complete for lines stronger than 11.0 mJy (7296 sources). The total redshift interval sensitive tomore » all damped Ly{alpha} (DLA) systems (N{sub H{sub i}}{>=}2 Multiplication-Sign 10{sup 20} cm{sup -2}) is {Delta}z = 7.0 (129 objects, assuming T{sub s} = 100 K and covering fraction unity); for super-DLAs (N{sub H{sub i}}{>=}2 Multiplication-Sign 10{sup 21} cm{sup -2}) it is {Delta}z = 128.2 (2353 objects). We re-detect the intrinsic H I absorption line in UGC 6081 but detect no intervening absorption line systems. We compute a 95% confidence upper limit on the column density frequency distribution function f(N{sub H{sub i}},X) spanning four orders of magnitude in column density, 10{sup 19} (T{sub s} /100 K) (1/f) cm{sup -2}ALFALFA survey-or any higher redshift, larger bandwidth, or more sensitive survey, such as those planned for Square Kilometer Array pathfinders or a low-frequency lunar array-will either make numerous detections or will set a strong statistical lower limit on the typical spin temperature of neutral hydrogen gas.« less

Reduction of Escherichia coli O157:H7 and Salmonella on laboratory-inoculated alfalfa seed with commercial citrus-related products.

PubMed

Fett, William F; Cooke, Peter H

2003-07-01

Alfalfa sprouts contaminated with the bacterial pathogens Escherichia coli O157:H7 and Salmonella have been the source of numerous outbreaks of foodborne illness in the United States and in other countries. The seed used for sprouting appears to be the primary source of these pathogens. The aim of this study was to determine whether the efficacy of commercial citrus-related products for sanitizing sprouting seed is similar to that of high levels of chlorine. Five products (Citrex, Pangermex, Citricidal, Citrobio, and Environné) were tested at concentrations of up to 20,000 ppm in sterile tap water and compared with buffered chlorine (at 16,000 ppm). Alfalfa seeds were inoculated with four-strain cocktails of Salmonella and E. coli O157:H7 to give final initial concentrations of ca. 9.0 and 7.0 CFU/g, respectively. Treatments (10 min) with Citrex, Pangermex, and Citricidal at 20,000 ppm and chlorine at 16,000 ppm produced similar log reductions for alfalfa seed inoculated with four-strain cocktails of E. coli O157:H7 and Salmonella (3.42 to 3.46 log CFU/g and 3.56 to 3.74 log CFU/g, respectively), and all four treatments were significantly (P<0.05) more effective than the control treatment (a buffer wash). Citrobio at 20,000 ppm was as effective as the other three products and chlorine against Salmonella but not against E. coli O157:H7. Environné was not more effective (producing reductions of 2.2 to 2.9 log CFU/g) than the control treatment (which produced reductions of 2.1 to 2.3 log CFU/g) against either pathogen. None of the treatments reduced seed germination. In vitro assays, as well as transmission electron microscopy, confirmed the antibacterial nature of the products that were effective against the two pathogens and indicated that they were bactericidal. When used at 20,000 ppm, the effective citrus-related products may be viable alternatives to chlorine for the sanitization of sprouting seed pending regulatory approval.

THE CLUSTERING OF ALFALFA GALAXIES: DEPENDENCE ON H I MASS, RELATIONSHIP WITH OPTICAL SAMPLES, AND CLUES OF HOST HALO PROPERTIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Papastergis, Emmanouil; Giovanelli, Riccardo; Haynes, Martha P.

We use a sample of ≈6000 galaxies detected by the Arecibo Legacy Fast ALFA (ALFALFA) 21 cm survey to measure the clustering properties of H I-selected galaxies. We find no convincing evidence for a dependence of clustering on galactic atomic hydrogen (H I) mass, over the range M{sub H{sub I}} ≈ 10{sup 8.5}-10{sup 10.5} M{sub ☉}. We show that previously reported results of weaker clustering for low H I mass galaxies are probably due to finite-volume effects. In addition, we compare the clustering of ALFALFA galaxies with optically selected samples drawn from the Sloan Digital Sky Survey (SDSS). We findmore » that H I-selected galaxies cluster more weakly than even relatively optically faint galaxies, when no color selection is applied. Conversely, when SDSS galaxies are split based on their color, we find that the correlation function of blue optical galaxies is practically indistinguishable from that of H I-selected galaxies. At the same time, SDSS galaxies with red colors are found to cluster significantly more than H I-selected galaxies, a fact that is evident in both the projected as well as the full two-dimensional correlation function. A cross-correlation analysis further reveals that gas-rich galaxies 'avoid' being located within ≈3 Mpc of optical galaxies with red colors. Next, we consider the clustering properties of halo samples selected from the Bolshoi ΛCDM simulation. A comparison with the clustering of ALFALFA galaxies suggests that galactic H I mass is not tightly related to host halo mass and that a sizable fraction of subhalos do not host H I galaxies. Lastly, we find that we can recover fairly well the correlation function of H I galaxies by just excluding halos with low spin parameter. This finding lends support to the hypothesis that halo spin plays a key role in determining the gas content of galaxies.« less