Science.gov

Sample records for diploid seedless watermelon

  1. Differential gene expression and alternative splicing between diploid and tetraploid watermelon lines

    USDA-ARS?s Scientific Manuscript database

    Synthetic tetraploid plants have been used for production of seedless triploid watermelon lines being pollinated with diploid plants. When compared to their diploid or triploid counterparts, the tetraploid exhibit wide phenotypic differences. Though many factors, including alternative splicing (AS),...

  2. Differential gene expression and alternative splicing between diploid and tetraploid watermelon

    PubMed Central

    Saminathan, Thangasamy; Nimmakayala, Padma; Manohar, Sumanth; Malkaram, Sridhar; Almeida, Aldo; Cantrell, Robert; Tomason, Yan; Abburi, Lavanya; Rahman, Mohammad A.; Vajja, Venkata G.; Khachane, Amit; Kumar, Brajendra; Rajasimha, Harsha K.; Levi, Amnon; Wehner, Todd; Reddy, Umesh K.

    2015-01-01

    The exploitation of synthetic polyploids for producing seedless fruits is well known in watermelon. Tetraploid progenitors of triploid watermelon plants, compared with their diploid counterparts, exhibit wide phenotypic differences. Although many factors modulate alternative splicing (AS) in plants, the effects of autopolyploidization on AS are still unknown. In this study, we used tissues of leaf, stem, and fruit of diploid and tetraploid sweet watermelon to understand changes in gene expression and the occurrence of AS. RNA-sequencing analysis was performed along with reverse transcription quantitative PCR and rapid amplification of cDNA ends (RACE)-PCR to demonstrate changes in expression and splicing. All vegetative tissues except fruit showed an increased level of AS in the tetraploid watermelon throughout the growth period. The ploidy levels of diploids and the tetraploid were confirmed using a ploidy analyser. We identified 5362 and 1288 genes that were up- and downregulated, respectively, in tetraploid as compared with diploid plants. We further confirmed that 22 genes underwent AS events across tissues, indicating possibilities of generating different protein isoforms with altered functions of important transcription factors and transporters. Arginine biosynthesis, chlorophyllide synthesis, GDP mannose biosynthesis, trehalose biosynthesis, and starch and sucrose degradation pathways were upregulated in autotetraploids. Phloem protein 2, chloroplastic PGR5-like protein, zinc-finger protein, fructokinase-like 2, MYB transcription factor, and nodulin MtN21 showed AS in fruit tissues. These results should help in developing high-quality seedless watermelon and provide additional transcriptomic information related to other cucurbits. PMID:25520388

  3. Differential gene expression and alternative splicing between diploid and tetraploid watermelon.

    PubMed

    Saminathan, Thangasamy; Nimmakayala, Padma; Manohar, Sumanth; Malkaram, Sridhar; Almeida, Aldo; Cantrell, Robert; Tomason, Yan; Abburi, Lavanya; Rahman, Mohammad A; Vajja, Venkata G; Khachane, Amit; Kumar, Brajendra; Rajasimha, Harsha K; Levi, Amnon; Wehner, Todd; Reddy, Umesh K

    2015-03-01

    The exploitation of synthetic polyploids for producing seedless fruits is well known in watermelon. Tetraploid progenitors of triploid watermelon plants, compared with their diploid counterparts, exhibit wide phenotypic differences. Although many factors modulate alternative splicing (AS) in plants, the effects of autopolyploidization on AS are still unknown. In this study, we used tissues of leaf, stem, and fruit of diploid and tetraploid sweet watermelon to understand changes in gene expression and the occurrence of AS. RNA-sequencing analysis was performed along with reverse transcription quantitative PCR and rapid amplification of cDNA ends (RACE)-PCR to demonstrate changes in expression and splicing. All vegetative tissues except fruit showed an increased level of AS in the tetraploid watermelon throughout the growth period. The ploidy levels of diploids and the tetraploid were confirmed using a ploidy analyser. We identified 5362 and 1288 genes that were up- and downregulated, respectively, in tetraploid as compared with diploid plants. We further confirmed that 22 genes underwent AS events across tissues, indicating possibilities of generating different protein isoforms with altered functions of important transcription factors and transporters. Arginine biosynthesis, chlorophyllide synthesis, GDP mannose biosynthesis, trehalose biosynthesis, and starch and sucrose degradation pathways were upregulated in autotetraploids. Phloem protein 2, chloroplastic PGR5-like protein, zinc-finger protein, fructokinase-like 2, MYB transcription factor, and nodulin MtN21 showed AS in fruit tissues. These results should help in developing high-quality seedless watermelon and provide additional transcriptomic information related to other cucurbits.

  4. Grafting Seedless Watermelons, How and Why? Will Grafting Help With Disease Control?

    USDA-ARS?s Scientific Manuscript database

    In recent years, the practice of grafting seedless watermelons (triploids) onto rootstocks belonging to other Cucurbitaceae genera has gained importance in the United States. Grafting vegetable crops, especially cucurbit’s, is very common in Europe and Asia. In these regions, the practice of crop ...

  5. Characterization and semiquantitative analysis of volatiles in seedless watermelon varieties using solid-phase microextraction.

    PubMed

    Beaulieu, John C; Lea, Jeanne M

    2006-10-04

    Seedless triploid watermelons have increased in popularity since the early 1990s, and the demand for seedless fruit is on the rise. Sweetness and sugars are crucial breeding focuses for fruit quality. Volatiles also play an important role; yet, we found no literature for seedless varieties and no reports using solid-phase microextraction (SPME) in watermelon. The objective of this experiment was to identify volatile and semivolatile compounds in five seedless watermelon varieties using carboxen divinylbenzene polydimethylsiloxane solid-phase microextraction (SPME) with gas chromatography-mass spectrometry (GC-MS). Fully ripe watermelon was squeezed through miracloth to produce rapid juice extracts for immediate headspace SPME GC-MS. Aldehydes, alcohols, ketones, and one furan (2-pentyl furan, a lipid oxidation product) were recovered. On the basis of total ion count peak area, the most abundant compounds in five varieties were 3-nonen-1-ol/(E,Z)-2,6-nonadienal (16.5-28.2%), (E)-2-nonenal (10.6-22.5%), and (Z)-6-nonenal (2.0-11.3%). Hexanal was most abundant (37.7%) in one variety (Petite Perfection) [corrected] The most abundant ketone was 6-methyl-5-hepten-2-one (2.7-7.7%). Some sensory attributes reported for these compounds are melon, citrus, cucumber, orange, rose, floral, guava, violet, vegetable, green, grassy, herbaceous, pungent, fatty, sweet, and waxy. Identifying and relating these compounds to sensory attributes will allow for future monitoring of the critical flavor compounds in seedless watermelon after processing and throughout fresh-cut storage.

  6. Utilizing Citrullus lanatus var. citroides germplasm for developing tetraploid lines useful as rootstocks and in breeding programs of seedless watermelon lines

    USDA-ARS?s Scientific Manuscript database

    In recent years, soil-borne diseases and pests have intensified in watermelon, particularly after the phasing out of the soil fumigant methyl bromide, and there is a continuous need to develop solutions for reducing the disease and pest pressure in this important cucurbit crop. Grafting of watermel...

  7. Carotenoid changes of intact watermelons after storage.

    PubMed

    Perkins-Veazie, Penelope; Collins, Julie K

    2006-08-09

    Watermelon contains lycopene, a red carotenoid pigment that has strong antioxidant properties. The lycopene content of watermelon is substantial, contributing 8-20 mg per 180 g serving. There are no reports on carotenoid changes in whole watermelon during storage. Three types of watermelon, open-pollinated seeded, hybrid seeded, and seedless types, were stored at 5, 13, and 21 degrees C for 14 days and flesh color, composition, and carotenoid content were compared to those of fruit not stored. Watermelons stored at 21 degrees C had increased pH, chroma, and carotenoid content compared to fresh fruit. Compared to fresh fruit, watermelons stored at 21 degrees C gained 11-40% in lycopene and 50-139% in beta-carotene, whereas fruit held at 13 degrees C changed little in carotenoid content. These results indicate that carotenoid biosynthesis in watermelons can be affected by temperature and storage.

  8. US SEEDLESS PINEAPPLE ORANGE

    USDA-ARS?s Scientific Manuscript database

    The Agricultural Research Service, U.S. Department of Agriculture, hereby releases for propagation the US SEEDLESS PINEAPPLE citrus scion selection, formerly tested as USDA 1-10-60. US SEEDLESS PINEAPPLE resulted from irradiation of Ridge Pineapple seeds by C.J. Hearn in 1970 at the U.S. Horticultu...

  9. Effect of phytophthora capsici crown rot on watermelon rootstocks and grafts

    USDA-ARS?s Scientific Manuscript database

    Crown and fruit rot caused by Phytophthora capsici is becoming an important and emerging disease of watermelon in the southeastern United States. In recent years, the practice of grafting seedless watermelons onto rootstocks belonging to other Cucurbitaceae genera is also gaining acceptance in our l...

  10. Resistance in watermelon rootstocks to crown rot caused by Phytophthora capsici

    USDA-ARS?s Scientific Manuscript database

    Phytophthora crown and fruit rot caused by Phytophthora capsici is becoming an important and emerging disease of watermelon (Citrullus lanatus) in south eastern United States. In recent years, the practice of grafting seedless watermelons (triploids) onto rootstocks belonging to other Cucurbitaceae...

  11. Accessions of Citrullus lanatus var. Citroides are Valuable Rootstocks for Grafted Watermelon in Fields Infested with Root-Knot Nematodes

    USDA-ARS?s Scientific Manuscript database

    Wild watermelon (Citrullus lanatus var. citroides) RKVL rootstock lines developed at the U.S. Vegetable Laboratory, USDA, ARS in Charleston, South Carolina, were compared to wild tinda and commercial cucurbit rootstock cultivars for grafting of seedless watermelon ‘Tri-X 313’ (C. lanatus var. lanatu...

  12. [Reasons that seedless fruits of Siraitia grosvenorii become small].

    PubMed

    Mo, Chang-Ming; Fu, Wei; Xing, Ai-Jia; Ma, Xiao-Jun; Luo, Hong; Tang, Qi

    2014-02-01

    To study the reasons that the seedless fruits of Siraitia grosvenorii developed to smaller ones. The differences of fruit expanding, gene expressing and cell development were investigated between the triploid and diploid fruits from two strains F050 and F049. The results showed the expanding of triploid fruits was stopped about 20 days after artificial pollination, 10 days earlier than the diploid fruits. Meanwhile, it was also investigated that aux expressing level in the triploid fruits was greatly higher than that in diploid fruits, while its ipt, cyt-p450, spds, cycB, cycD1, cycD3, cdkA, cdkB, exp and xth expressing level were greatly lower than that in diploid fruits. The majority of sarcocarp cells of the triploid fruits kept in the stage of small ones comparing with the diploid fruits. The expression of the genes of the proteins involving cell division and expansion was inhibited as the significant reduction of endogenous IAA, CTK, GA and SPDS after bad fertilization and the embryo abortion, which resulted in the end of division and extension of sarcocarp cells. Above reasons induce small fruits of triploid seedless Siraitia grosvenorii.

  13. Evaluation of Actigard and fungicides for management of Phytophthora fruit rot of watermelon, 2013

    USDA-ARS?s Scientific Manuscript database

    The experiment was conducted at the U.S. Vegetable Laboratory farm in Charleston, SC, in summer of 2013. The soil was Yonges loamy fine sand and the field has been infested with Phytophthora capsici for the previous 2 years. Five-week-old seedlings of the seedless watermelon cultivar Vanessa growi...

  14. Evaluation of watermelon varieties for tolerance to powdery mildew and Phytophthora fruit rot, 2014

    USDA-ARS?s Scientific Manuscript database

    This experiment was conducted at the U.S. Vegetable Laboratory farm in Charleston, SC. The soil was Yonges loamy fine sand. This study was undertaken to determine the performance of seeded and seedless commercial watermelon varieties for tolerance to powdery mildew (PM) and Phytophthora fruit rot as...

  15. 7 CFR 52.1849 - Grades of golden seedless raisins.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Grades of golden seedless raisins. 52.1849 Section 52... Processed Raisins 1 Type II-Golden Seedless Raisins § 52.1849 Grades of golden seedless raisins. Except for color, the grades of Golden Seedless Raisins are the same as for Seedless Raisins (See § 52.1846...

  16. 7 CFR 52.1849 - Grades of golden seedless raisins.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Grades of golden seedless raisins. 52.1849 Section 52... Processed Raisins 1 Type II-Golden Seedless Raisins § 52.1849 Grades of golden seedless raisins. Except for color, the grades of Golden Seedless Raisins are the same as for Seedless Raisins (See § 52.1846...

  17. 7 CFR 52.1848 - Sizes of golden seedless raisins.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Sizes of golden seedless raisins. 52.1848 Section 52... Processed Raisins 1 Type II-Golden Seedless Raisins § 52.1848 Sizes of golden seedless raisins. The size designations and measurement requirements for the respective sizes of Golden Seedless Raisins are the same...

  18. 7 CFR 52.1848 - Sizes of golden seedless raisins.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Sizes of golden seedless raisins. 52.1848 Section 52... Processed Raisins 1 Type II-Golden Seedless Raisins § 52.1848 Sizes of golden seedless raisins. The size designations and measurement requirements for the respective sizes of Golden Seedless Raisins are the same...

  19. 7 CFR 52.1847 - Colors of golden seedless raisins.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Colors of golden seedless raisins. 52.1847 Section 52... Processed Raisins 1 Type II-Golden Seedless Raisins § 52.1847 Colors of golden seedless raisins. The color of Golden Seedless Raisins is not a factor of quality for the purpose of these grades. The color...

  20. 7 CFR 52.1847 - Colors of golden seedless raisins.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Colors of golden seedless raisins. 52.1847 Section 52... Processed Raisins 1 Type II-Golden Seedless Raisins § 52.1847 Colors of golden seedless raisins. The color of Golden Seedless Raisins is not a factor of quality for the purpose of these grades. The color...

  1. Watermelon, phytochemicals and health

    USDA-ARS?s Scientific Manuscript database

    Watermelon fruit contains lycopene, a carotenoid pigment, and citrulline, an amino acid. These plant compounds may be helpful in preventing some chronic diseases. The amount of lycopene in watermelon ranges from 35 to 125 mg per kg of edible portion, and there is 2 to 4 mg per kg citrulline presen...

  2. Genetic Resources of Watermelon

    USDA-ARS?s Scientific Manuscript database

    As a result of many years of domestication and selection for desirable fruit quality, watermelon cultivars (Citrullus lanatus) share a narrow genetic base. Africa is the center of origin and diversity of watermelon and is considered to be the central continent for collecting and conserving useful ge...

  3. 7 CFR 52.1849 - Grades of golden seedless raisins.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Grades of golden seedless raisins. 52.1849 Section 52... PROCESSED FOOD PRODUCTS 1 United States Standards for Grades of Processed Raisins 1 Type II-Golden Seedless Raisins § 52.1849 Grades of golden seedless raisins. Except for color, the grades of Golden...

  4. 7 CFR 52.1849 - Grades of golden seedless raisins.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Grades of golden seedless raisins. 52.1849 Section 52... PROCESSED FOOD PRODUCTS 1 United States Standards for Grades of Processed Raisins 1 Type II-Golden Seedless Raisins § 52.1849 Grades of golden seedless raisins. Except for color, the grades of Golden...

  5. 7 CFR 52.1848 - Sizes of golden seedless raisins.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Sizes of golden seedless raisins. 52.1848 Section 52... PROCESSED FOOD PRODUCTS 1 United States Standards for Grades of Processed Raisins 1 Type II-Golden Seedless Raisins § 52.1848 Sizes of golden seedless raisins. The size designations and measurement requirements...

  6. 7 CFR 52.1848 - Sizes of golden seedless raisins.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Sizes of golden seedless raisins. 52.1848 Section 52... PROCESSED FOOD PRODUCTS 1 United States Standards for Grades of Processed Raisins 1 Type II-Golden Seedless Raisins § 52.1848 Sizes of golden seedless raisins. The size designations and measurement requirements...

  7. 7 CFR 52.1848 - Sizes of golden seedless raisins.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Sizes of golden seedless raisins. 52.1848 Section 52... PROCESSED FOOD PRODUCTS 1 United States Standards for Grades of Processed Raisins 1 Type II-Golden Seedless Raisins § 52.1848 Sizes of golden seedless raisins. The size designations and measurement requirements...

  8. 7 CFR 52.1849 - Grades of golden seedless raisins.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Grades of golden seedless raisins. 52.1849 Section 52... PROCESSED FOOD PRODUCTS 1 United States Standards for Grades of Processed Raisins 1 Type II-Golden Seedless Raisins § 52.1849 Grades of golden seedless raisins. Except for color, the grades of Golden...

  9. 7 CFR 52.1847 - Colors of golden seedless raisins.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Colors of golden seedless raisins. 52.1847 Section 52... Raisins § 52.1847 Colors of golden seedless raisins. The color of Golden Seedless Raisins is not a factor of quality for the purpose of these grades. The color requirements applicable to the respective color...

  10. 7 CFR 52.1847 - Colors of golden seedless raisins.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Colors of golden seedless raisins. 52.1847 Section 52... Raisins § 52.1847 Colors of golden seedless raisins. The color of Golden Seedless Raisins is not a factor of quality for the purpose of these grades. The color requirements applicable to the respective color...

  11. 7 CFR 52.1847 - Colors of golden seedless raisins.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Colors of golden seedless raisins. 52.1847 Section 52... Raisins § 52.1847 Colors of golden seedless raisins. The color of Golden Seedless Raisins is not a factor of quality for the purpose of these grades. The color requirements applicable to the respective color...

  12. Detecting compact binary coalescences with seedless clustering

    NASA Astrophysics Data System (ADS)

    Coughlin, M.; Thrane, E.; Christensen, N.

    2014-10-01

    Compact binary coalescences are a promising source of gravitational waves for second-generation interferometric gravitational-wave detectors. Although matched filtering is the optimal search method for well-modeled systems, alternative detection strategies can be used to guard against theoretical errors (e.g., involving new physics and/or assumptions about spin or eccentricity) while providing a measure of redundancy. In a previous paper, we showed how "seedless clustering" can be used to detect long-lived gravitational-wave transients in both targeted and all-sky searches. In this paper, we apply seedless clustering to the problem of low-mass (Mtotal≤10M⊙) compact binary coalescences for both spinning and eccentric systems. We show that seedless clustering provides a robust and computationally efficient method for detecting low-mass compact binaries.

  13. Seed-less iodine-125 ophthalmic applicator.

    PubMed

    Puchalska, Izabela; Mielcarski, Mieczyslaw

    2003-01-01

    A method of preparation a seed-less active insert of iodine-125 ophthalmic applicator is described. Internal electrolysis was applied for fixing iodine-125 on the concave surface of the silver shell which is afterwards hermetically sealed inside a spherically shaped acrylic insert. The current-voltage characteristics of the galvanic cell used for deposition of silver iodide were determined. The results of the measurements of the energy spectra of the radiation emitted by a seed-less and seed-containing applicator are presented. The iodine-125 surface distribution uniformity on a silver shell was measured. The depth dose rate measurements indicate that the total activity incorporated in a seed-less applicator can be lower than that in seed-containing, while simultaneously assuring the desired dose rate. Copyright 2002 Elsevier Science Ltd.

  14. 7 CFR 1210.305 - Watermelon.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Watermelon. 1210.305 Section 1210.305 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE WATERMELON RESEARCH AND PROMOTION PLAN Watermelon Research and Promotion Plan Definitions § 1210.305 Watermelon. Watermelon means all...

  15. 7 CFR 1210.305 - Watermelon.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Watermelon. 1210.305 Section 1210.305 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE WATERMELON RESEARCH AND PROMOTION PLAN Watermelon Research and Promotion Plan Definitions § 1210.305 Watermelon. Watermelon means all...

  16. 7 CFR 1210.305 - Watermelon.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Watermelon. 1210.305 Section 1210.305 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE WATERMELON RESEARCH AND PROMOTION PLAN Watermelon Research and Promotion Plan Definitions § 1210.305 Watermelon. Watermelon means all...

  17. 7 CFR 1210.305 - Watermelon.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Watermelon. 1210.305 Section 1210.305 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE WATERMELON RESEARCH AND PROMOTION PLAN Watermelon Research and Promotion Plan Definitions § 1210.305 Watermelon. Watermelon means...

  18. 7 CFR 1210.305 - Watermelon.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Watermelon. 1210.305 Section 1210.305 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE WATERMELON RESEARCH AND PROMOTION PLAN Watermelon Research and Promotion Plan Definitions § 1210.305 Watermelon. Watermelon means...

  19. Seed formation in triploid loquat (Eriobotrya japonica) through cross-hybridization with pollen of diploid cultivars

    PubMed Central

    Kikuchi, Shinji; Iwasuna, Miwako; Kobori, Aya; Tsutaki, Yasunori; Yoshida, Akihiro; Murota, Yuri; Nishino, Eisho; Sassa, Hidenori; Koba, Takato

    2014-01-01

    As the fruits of loquat (Eriobotrya japonica, 2n = 2x = 34) carry large seeds, the breeding of seedless loquat has long been a goal. The recent creation of triploid cultivars (2n = 3x = 51) and the application of gibberellins allow commercial production of seedless loquat, but the possibility of seed formation in triploid loquats has not been carefully investigated. Through crossing experiments and cytological observations of meiosis and pollen tube growth, we found that the triploid line 3N-N28 was essentially self-sterile, but developed seeds on pollination with pollen from diploid cultivars at rates of up to 5.5%. Almost half of the seedlings survived to 5 months, and carried diploid (2n = 34), tetraploid (2n = 68), or aneuploid chromosome numbers. Our results suggest that triploid loquat cultivars might retain the risk of seed formation. Protection from pollination by diploid cultivars or the development of new triploid cultivars will be necessary to ensure the production of seedless loquat fruits. PMID:24987304

  20. Bioactive compounds from flesh and by-product of fresh-cut watermelon cultivars.

    PubMed

    Tarazona-Díaz, Martha Patricia; Viegas, Joana; Moldao-Martins, Margarida; Aguayo, Encarna

    2011-03-30

    The fresh-cut industry produces thousands of tons of waste in non-edible portions that present an environmental and management problem. These by-products could be reused, in particular, to obtain bioactive compounds. In this study, five different fresh-cut watermelon cultivars were assessed for their flesh and by-product bioactive contents. The amount of by-product varied between 31.27 and 40.61% of initial fresh weight (f.w.) depending on the cultivar. Watermelon cultivars were poor sources of total antioxidant, and the content was similar between rind and flesh samples (46.96 vs 43.46 mg ascorbic acid equivalent antioxidant capacity kg(-1) f.w.). However, the rind had a moderate total phenolic content higher than that of the flesh (458 vs 389 mg chlorogenic acid equivalent kg(-1) f.w.) and a much higher content of the amino acid citrulline (3.34 vs 2.33 g kg(-1) f.w.), which has potential bioactive properties. Watermelon rind offers quantitative interest as a natural source of citrulline, particularly Fashion, a dark-skinned, seedless cultivar. More research is required on the efficient extraction of citrulline from watermelon rind and its suitability as an additive to drinks, juices or others products to produce new functional food products with valid health claims. Copyright © 2010 Society of Chemical Industry.

  1. Selecting Schizosaccharomyces pombe Diploids.

    PubMed

    Ekwall, Karl; Thon, Geneviève

    2017-07-05

    Here we describe procedures for the selection of diploid Schizosaccharomyces pombeade6-M210/ade6-M216 heteroallelic complementation is widely used to select for Ade(+) diploids. Such diploids will readily sporulate when starved of nitrogen. For some investigations, stable diploids are preferable (e.g., for genetic complementation tests), and in these cases mating an h(-) strain with an h(90) mat2-Pi-102 strain can be used to prevent sporulation. When ade6-M210/ade6-M216 mutations impact on, or show synthetic interactions with, the gene of interest, two different auxotrophic markers can be used to select complementation. © 2017 Cold Spring Harbor Laboratory Press.

  2. Gamma rays produce superior seedless citrus

    SciTech Connect

    Pyrah, D.

    1984-10-01

    Using gamma radiation, seedless forms of some varieties of oranges and grapefruit are being produced. Since it has long been known that radiation causes mutations in plants and animals, experiments were conducted to determine if seediness could be altered by exposing seeds or budwood to higher than natural doses of gamma radiation. Orange and grapefruit seeds and cuttings exposed to gamma rays in the early 1970's have produced trees that bear fruit superior to that now on the market.

  3. Diploid versus Haploid Organisms

    NASA Astrophysics Data System (ADS)

    Ticona, Armando; de Oliveira, Paulo Murilo C.

    Using a bit string model, we show that asexual reproduction for diploids is more efficient than for haploids: it improves genetic material producing new individuals with less deleterious mutations. We also see that in a system where competition is present, diploids dominate, even though we consider some dominant loci.

  4. Cutting Watermelon: Lessons in Instructional Coaching

    ERIC Educational Resources Information Center

    Sandstead, Martha

    2016-01-01

    Literacy coordinator Martha Sandstead finds inspiration for her coaching work in a quote from civil rights organizer Lawrence Guyot: "Let's say you're riding past a picnic, and people are cuttin' watermelons. You don't immediately go and say, "stop the watermelon cutting" and let's talk. … You cut some watermelons, or you help…

  5. Cutting Watermelon: Lessons in Instructional Coaching

    ERIC Educational Resources Information Center

    Sandstead, Martha

    2016-01-01

    Literacy coordinator Martha Sandstead finds inspiration for her coaching work in a quote from civil rights organizer Lawrence Guyot: "Let's say you're riding past a picnic, and people are cuttin' watermelons. You don't immediately go and say, "stop the watermelon cutting" and let's talk. … You cut some watermelons, or you help…

  6. Watermelon and ragweed share allergens.

    PubMed

    Enberg, R N; Leickly, F E; McCullough, J; Bailey, J; Ownby, D R

    1987-06-01

    A biotin-avidin amplified ELISA was used to measure antigen-specific IgE for ragweed, representative members of the gourd family (watermelon, cantaloupe, honeydew melon, zucchini, and cucumber), and banana in the sera of 192 allergic patients, each with an IgE greater than or equal to 180 microns/ml. Sixty-three percent (120/192) of the sera contained antiragweed IgE, and of these patients, 28% to 50% contained IgE specific for any single gourd family member. In contrast, no greater than 11% of the sera positive for a given gourd or banana were negative for ragweed. Correlations between ragweed and gourd-specific IgE levels were significant (p less than 0.001), and correlation coefficients between any two gourds exceeded 0.79. In an ELISA system, the extracts of watermelon and ragweed inhibited each other in a dose-dependent manner; the resulting nonparallel inhibition curves indicate that some, but not all, of the allergens in the two extracts are cross-reactive. Isoelectric focusing of watermelon and ragweed extracts in narrow range gel (pH 4 to 6) followed by immunoblotting demonstrated six watermelon allergen bands with isoelectric points identical to those of ragweed allergens. Several remaining bands in the two extracts had differing isoelectric points, however. Six of 26 patients interviewed with watermelon-specific IgE reported developing oropharyngeal symptoms (itching and/or swelling of the lips, tongue, or throat) after ingesting at least one of the study foods, whereas only one of 25 patients interviewed without detectable watermelon-specific IgE reported similar symptoms (p = 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Comparative transcriptome analysis during early fruit development between three seedy citrus genotypes and their seedless mutants

    USDA-ARS?s Scientific Manuscript database

    Identification of genes with differential transcript abundance (GDTA) in seedless mutants may enhance understanding of seedless citrus development. Transcriptome analysis was conducted at three time points during early fruit development (Phase 1) of three seedy citrus genotypes: Fallglo [Bower citru...

  8. Medieval iconography of watermelons in Mediterranean Europe.

    PubMed

    Paris, Harry S; Daunay, Marie-Christine; Janick, Jules

    2013-09-01

    The watermelon, Citrullus lanatus (Cucurbitaceae), is an important fruit vegetable in the warmer regions of the world. Watermelons were illustrated in Mediterranean Antiquity, but not as frequently as some other cucurbits. Little is known concerning the watermelons of Mediterranean Europe during medieval times. With the objective of obtaining an improved understanding of watermelon history and diversity in this region, medieval drawings purportedly of watermelons were collected, examined and compared for originality, detail and accuracy. The oldest manuscript found that contains an accurate, informative image of watermelon is the Tractatus de herbis, British Library ms. Egerton 747, which was produced in southern Italy, around the year 1300. A dozen more original illustrations were found, most of them from Italy, produced during the ensuing two centuries that can be positively identified as watermelon. In most herbal-type manuscripts, the foliage is depicted realistically, the plants shown as having long internodes, alternate leaves with pinnatifid leaf laminae, and the fruits are small, round and striped. The manuscript that contains the most detailed and accurate image of watermelon is the Carrara Herbal, British Library ms. Egerton 2020. In the agriculture-based manuscripts, the foliage, if depicted, is not accurate, but variation in the size, shape and coloration of the fruits is evident. Both red-flesh and white-flesh watermelons are illustrated, corresponding to the typical sweet dessert watermelons so common today and the insipid citron watermelons, respectively. The variation in watermelon fruit size, shape and coloration depicted in the illustrations indicates that at least six cultivars of watermelon are represented, three of which probably had red, sweet flesh and three of which appear to have been citrons. Evidently, citron watermelons were more common in Mediterranean Europe in the past than they are today.

  9. Medieval iconography of watermelons in Mediterranean Europe

    PubMed Central

    Paris, Harry S.; Daunay, Marie-Christine; Janick, Jules

    2013-01-01

    Background and Aims The watermelon, Citrullus lanatus (Cucurbitaceae), is an important fruit vegetable in the warmer regions of the world. Watermelons were illustrated in Mediterranean Antiquity, but not as frequently as some other cucurbits. Little is known concerning the watermelons of Mediterranean Europe during medieval times. With the objective of obtaining an improved understanding of watermelon history and diversity in this region, medieval drawings purportedly of watermelons were collected, examined and compared for originality, detail and accuracy. Findings The oldest manuscript found that contains an accurate, informative image of watermelon is the Tractatus de herbis, British Library ms. Egerton 747, which was produced in southern Italy, around the year 1300. A dozen more original illustrations were found, most of them from Italy, produced during the ensuing two centuries that can be positively identified as watermelon. In most herbal-type manuscripts, the foliage is depicted realistically, the plants shown as having long internodes, alternate leaves with pinnatifid leaf laminae, and the fruits are small, round and striped. The manuscript that contains the most detailed and accurate image of watermelon is the Carrara Herbal, British Library ms. Egerton 2020. In the agriculture-based manuscripts, the foliage, if depicted, is not accurate, but variation in the size, shape and coloration of the fruits is evident. Both red-flesh and white-flesh watermelons are illustrated, corresponding to the typical sweet dessert watermelons so common today and the insipid citron watermelons, respectively. The variation in watermelon fruit size, shape and coloration depicted in the illustrations indicates that at least six cultivars of watermelon are represented, three of which probably had red, sweet flesh and three of which appear to have been citrons. Evidently, citron watermelons were more common in Mediterranean Europe in the past than they are today. PMID:23904443

  10. New flesh colors in watermelon?

    USDA-ARS?s Scientific Manuscript database

    There are currently six published flesh colors in watermelon along with the associated genes for each of the designated flesh colors. Previous results have shown that segregation patterns did not fit with published results for canary yellow and red flesh. We believe that part of the problem has been...

  11. Seedless Fruit Production by Hormonal Regulation of Fruit Set

    PubMed Central

    Pandolfini, Tiziana

    2009-01-01

    Seed and fruit development are intimately related processes controlled by internal signals and environmental cues. The absence of seeds is usually appreciated by consumers and producers because it increases fruit quality and fruit shelf-life. One method to produce seedless fruit is to develop plants able to produce fruits independently from pollination and fertilization of the ovules. The onset of fruit growth is under the control of phytohormones. Recent genomic studies have greatly contributed to elucidate the role of phytohormones in regulating fruit initiation, providing at the same time genetic methods for introducing seedlessness in horticultural plants. PMID:22253976

  12. A seedless approach to continuous flow synthesis of gold nanorods.

    PubMed

    Bullen, Craig; Latter, Melissa J; D'Alonzo, Nicholas J; Willis, Glen J; Raston, Colin L

    2011-04-14

    A direct seedless method for the continuous synthesis of gold nanorods has been developed using a sequential rotating tube-narrow channel processing microfluidic configuration, with the stock feed solutions (HAuCl(4)/CTAB/acetylacetone and AgNO(3)/CTAB/carbonate buffer) being stable for weeks.

  13. 7 CFR 989.7 - Golden Seedless raisins.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Golden Seedless raisins. 989.7 Section 989.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM...

  14. 7 CFR 989.7 - Golden Seedless raisins.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Golden Seedless raisins. 989.7 Section 989.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM...

  15. 7 CFR 989.7 - Golden Seedless raisins.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Golden Seedless raisins. 989.7 Section 989.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM...

  16. 7 CFR 989.7 - Golden Seedless raisins.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Golden Seedless raisins. 989.7 Section 989.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM...

  17. 7 CFR 989.7 - Golden Seedless raisins.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Golden Seedless raisins. 989.7 Section 989.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES...

  18. 7 CFR 52.1846 - Grades of seedless raisins.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... PROCESSED FOOD PRODUCTS 1 United States Standards for Grades of Processed Raisins 1 Type I-Seedless Raisins... 35 Maximum (percent by weight) Sugared 5 10 15 Discolored, damaged or moldy raisins 4 6 9 Provided these limits are not exceeded: Damaged 2 3 5 Moldy 2 3 4 Total Substandard development and undeveloped...

  19. 7 CFR 52.1846 - Grades of seedless raisins.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... PROCESSED FOOD PRODUCTS 1 United States Standards for Grades of Processed Raisins 1 Type I-Seedless Raisins... 35 Maximum (percent by weight) Sugared 5 10 15 Discolored, damaged or moldy raisins 4 6 9 Provided these limits are not exceeded: Damaged 2 3 5 Moldy 2 3 4 Total Substandard development and undeveloped...

  20. 7 CFR 52.1846 - Grades of seedless raisins.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... PROCESSED FOOD PRODUCTS 1 United States Standards for Grades of Processed Raisins 1 Type I-Seedless Raisins... 35 Maximum (percent by weight) Sugared 5 10 15 Discolored, damaged or moldy raisins 4 6 9 Provided these limits are not exceeded: Damaged 2 3 5 Moldy 2 3 4 Total Substandard development and undeveloped...

  1. Comparative transcriptome analysis during early fruit development between three seedy citrus genotypes and their seedless mutants

    PubMed Central

    Zhang, Shujian; Shi, Qingchun; Albrecht, Ute; Shatters, Robert G; Stange, Ric; McCollum, Greg; Zhang, Shuo; Fan, Chengming; Stover, Ed

    2017-01-01

    Identification of genes with differential transcript abundance (GDTA) in seedless mutants may enhance understanding of seedless citrus development. Transcriptome analysis was conducted at three time points during early fruit development (Phase 1) of three seedy citrus genotypes: Fallglo (Bower citrus hybrid (Citrus reticulata×C. reticulata×C. paradisi)×Temple (C. reticulata×C. sinensis)), grapefruit (C. paradisi), Pineapple sweet orange (C. sinensis), and their seedless mutants. Seed abortion in seedless mutants was observed at 26 days post anthesis (Time point 2). Affymetrix transcriptomic analysis revealed 359 to 1077 probe sets with differential transcript abundance in the comparison of seedless versus seedy fruits for each citrus genotypes and time points. The GDTA identified by 18 microarray probe sets were validated by qPCR. Hierarchical clustering analysis revealed a range of GDTA associated with development, hormone and protein metabolism, all of which may reflect genes associated with seedless fruit development. There were 14, 9 and 12 genes found exhibiting similar abundance ratios in all three seedless versus seedy genotype comparisons at time point 1, 2 and 3, respectively. Among those genes were genes coding for an aspartic protease and a cysteine protease, which may play important roles in seedless fruit development. New insights into seedless citrus fruit development may contribute to biotech approaches to create seedless cultivars. PMID:28904803

  2. Gene expression in developing watermelon fruit

    USDA-ARS?s Scientific Manuscript database

    A microarray and Real-Time PCR-based study was conducted in watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai var. lanatus] in order to elucidate the flow of events associated with fruit development and ripening in this species. RNA from three different maturation stages of watermelon fruit, a...

  3. Expression and Polymorphism of Watermelon Fruit ESTs

    USDA-ARS?s Scientific Manuscript database

    Over 8,000 ESTs were generated for watermelon and were assembled into 4,700 EST-unigenes (http://www.icugi.org). Microarray and Real-Time PCR analyses were used to examine differential expression of 832 of these EST-unigenes in developing and ripening watermelon fruit. RNA was isolated from waterm...

  4. Watermelon lycopene and allied health claims

    PubMed Central

    Naz, Ambreen; Butt, Masood Sadiq; Sultan, Muhammad Tauseef; Qayyum, Mir Muhammad Nasir; Niaz, Rai Shahid

    2014-01-01

    Presently, functional foods and nutraceuticals are gaining immense importance in the prevention of various maladies through dietary regimen module. Consumption of fruits and vegetables based diet has pursuit a range of bioactive components, especially phytochemicals targeting life threatening ailments. In this context, lycopene is an extensively studied antioxidant potentially present in watermelon, tomato, pink guava etc. Watermelon is one of the unique sources having readily available cis-isomeric lycopene. The distinctive aroma of watermelon is imparted by medium- and short-chain fatty acids along with geranial, ß-ionone and neral. Its consumption has been escalated owing to rich nutritional profile and allied health benefits. It is effective in reducing the extent of cancer insurgence, cardiovascular disorders, diabetes and macular diseases. The structural characteristics, physiochemical properties and therapeutic effects of lycopene are the limelight of the manuscript. However, further research investigations are still needed to address the health enhancing potential of watermelon lycopene. PMID:26417290

  5. Watermelon lycopene and allied health claims.

    PubMed

    Naz, Ambreen; Butt, Masood Sadiq; Sultan, Muhammad Tauseef; Qayyum, Mir Muhammad Nasir; Niaz, Rai Shahid

    2014-01-01

    Presently, functional foods and nutraceuticals are gaining immense importance in the prevention of various maladies through dietary regimen module. Consumption of fruits and vegetables based diet has pursuit a range of bioactive components, especially phytochemicals targeting life threatening ailments. In this context, lycopene is an extensively studied antioxidant potentially present in watermelon, tomato, pink guava etc. Watermelon is one of the unique sources having readily available cis-isomeric lycopene. The distinctive aroma of watermelon is imparted by medium- and short-chain fatty acids along with geranial, ß-ionone and neral. Its consumption has been escalated owing to rich nutritional profile and allied health benefits. It is effective in reducing the extent of cancer insurgence, cardiovascular disorders, diabetes and macular diseases. The structural characteristics, physiochemical properties and therapeutic effects of lycopene are the limelight of the manuscript. However, further research investigations are still needed to address the health enhancing potential of watermelon lycopene.

  6. Gene expression in developing watermelon fruit

    PubMed Central

    Wechter, W Patrick; Levi, Amnon; Harris, Karen R; Davis, Angela R; Fei, Zhangjun; Katzir, Nurit; Giovannoni, James J; Salman-Minkov, Ayelet; Hernandez, Alvaro; Thimmapuram, Jyothi; Tadmor, Yaakov; Portnoy, Vitaly; Trebitsh, Tova

    2008-01-01

    Background Cultivated watermelon form large fruits that are highly variable in size, shape, color, and content, yet have extremely narrow genetic diversity. Whereas a plethora of genes involved in cell wall metabolism, ethylene biosynthesis, fruit softening, and secondary metabolism during fruit development and ripening have been identified in other plant species, little is known of the genes involved in these processes in watermelon. A microarray and quantitative Real-Time PCR-based study was conducted in watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai var. lanatus] in order to elucidate the flow of events associated with fruit development and ripening in this species. RNA from three different maturation stages of watermelon fruits, as well as leaf, were collected from field grown plants during three consecutive years, and analyzed for gene expression using high-density photolithography microarrays and quantitative PCR. Results High-density photolithography arrays, composed of probes of 832 EST-unigenes from a subtracted, fruit development, cDNA library of watermelon were utilized to examine gene expression at three distinct time-points in watermelon fruit development. Analysis was performed with field-grown fruits over three consecutive growing seasons. Microarray analysis identified three hundred and thirty-five unique ESTs that are differentially regulated by at least two-fold in watermelon fruits during the early, ripening, or mature stage when compared to leaf. Of the 335 ESTs identified, 211 share significant homology with known gene products and 96 had no significant matches with any database accession. Of the modulated watermelon ESTs related to annotated genes, a significant number were found to be associated with or involved in the vascular system, carotenoid biosynthesis, transcriptional regulation, pathogen and stress response, and ethylene biosynthesis. Ethylene bioassays, performed with a closely related watermelon genotype with a similar

  7. 7 CFR 905.153 - Procedure for determining handlers' permitted quantities of red seedless grapefruit when a...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... quantities of red seedless grapefruit when a portion of sizes 48 and 56 of such variety is restricted. 905... § 905.153 Procedure for determining handlers' permitted quantities of red seedless grapefruit when a... three seasons. Each handler's average week shall be computed by adding the total volume of red seedless...

  8. Biochemical characteristics and thermal inhibition kinetics of polyphenol oxidase extracted from Thompson seedless grape

    USDA-ARS?s Scientific Manuscript database

    Polyphenol oxidase (PPO) was isolated from Thompson seedless grape (Vitis vinifera 'Thompson Seedless') and its biochemical characteristics were studied. Optimum pH and temperature for grape PPO activity were pH 6.0 and 25 degrees C with 10 mM catechol as substrate. The enzyme was heat-stable betwee...

  9. Transcriptome Analysis of Early Fruit Development in Three Seedy Citrus Genotypes and Their Seedless Mutants

    USDA-ARS?s Scientific Manuscript database

    Seedlessness is desirable for most citrus fruit, and identification of spontaneous or irradiated seedless mutants is important in developing citrus cultivars. We conducted a transcriptome analysis in early fruit development of three seedy citrus types (‘Fallglo’, a largely C. reticulata hybrid; ‘Pi...

  10. Physiological effects of Squash vein yellowing virus infection on watermelon

    USDA-ARS?s Scientific Manuscript database

    Squash vein yellowing virus (SqVYV) is the cause of viral watermelon vine decline. In this study, watermelon plants of different ages were inoculated with SqVYV to characterize the physiological response to infection and provide new insights into watermelon vine decline. Physiological responses to...

  11. Grafting for Management of Root-Knot Nematodes in Watermelon

    USDA-ARS?s Scientific Manuscript database

    Five wild watermelon (Citrullus lanatus var. citroides) germplasm lines, four bottlegourd (Lagenaria siceraria) cultivars, one squash (Cucurbita moschata x C. maxima) hybrid, and one commercial wild watermelon (C. lanatus spp.) cultivar were evaluated as rootstocks for watermelon in a field infested...

  12. Adding value to grafted watermelon: Novel benefits and potential pitfalls

    USDA-ARS?s Scientific Manuscript database

    Grafted watermelons are commonly used in Asia and areas of Europe but are not widely used in the United States. The traditional reason for grafting watermelons has been for resistance to soil borne diseases such as Fusarium. We began to explore novel benefits which might make grafted watermelons m...

  13. Resistance to papaya ringspot virus-watermelon strain (PRSV-W) in the desert watermelon Citrullus colocynthis

    USDA-ARS?s Scientific Manuscript database

    The bitter desert watermelon (Citrullus colocynthis) is a valuable source for improving disease or pest resistance in watermelon cultivars. The objective of this study was to identify C. colocynthis accessions displaying resistance to the papaya ringspot virus-watermelon strain (PRSV-W) that could ...

  14. Seedless synthesis of gold nanorods using resveratrol as a reductant

    NASA Astrophysics Data System (ADS)

    Wang, Wenjing; Li, Jing; Lan, Shijie; Rong, Li; Liu, Yi; Sheng, Yu; Zhang, Hao; Yang, Bai

    2016-04-01

    Gold nanorods (GNRs) attract extensive attention in current diagnostic and therapeutic applications which require the synthesis of GNRs with high yields, adjustable aspect ratio, size monodispersity, and easy surface decoration. In the seed-mediated synthesis of GNRs using cetyl trimethyl ammonium bromide (CTAB) micelles as templates, the additives of aromatic compounds have been found to be important for improving the size monodispersity of the as-synthesized GNRs; this is hopeful in terms of the further optimization of the synthetic methodology of GNRs. In this work, resveratrol, a natural polyphenol in grapes with an anti-oxidization behavior, is employed as the reductant for the seedless synthesis of GNRs with a good size monodispersity and a tunable aspect ratio. Accordingly, the longitudinal localized surface plasmon resonance (LSPR) peak is tunable from 570 to 950 nm. The success of our approach is attributed to the aromatic structure and mild reducibility of resveratrol. The embedment of resveratrol into CTAB micelles strengthens the facet-selective adsorption of CTAB, and therewith facilitates the anisotropic growth of GNRs. In addition, the mild reducibility of resveratrol is capable of supporting GNR growth by avoiding secondary nucleation, thus allowing the seedless synthesis of GNRs with a good size monodispersity. As a chemopreventive agent, the combination of resveratrol in GNR synthesis will consolidate the theranostic applications of GNRs.

  15. Isolation and characterization of latent and active polyphenoloxidase in BRS Clara (CNPUV 154-147 × Centennial seedless) and BRS Morena (Marroo seedless × Centennial seedless) seedless table grapes.

    PubMed

    Lago-Vanzela, Ellen Silva; Pavezzi, Fabiana Carina; Martin, Natália; Gomes, Eleni; Da Silva, Roberto

    2011-11-01

    The seedless grapes BRS Clara and BRS Morena, developed in Brazil, are currently growing in popularity due to their premium texture and taste. However, there are no reports on the polyphenoloxidase (PPO) from these cultivars. In this paper, active and latent PPO from BRS Clara and BRS Morena seedless grapes were extracted using the non-ionic detergents Triton-X-100 (active) and Triton-X-114 (latent), and their catecholase activities were characterized. The PPO extracted using Triton-X-110 exhibited maximum activities at pH 6.0 and at 25 °C. Above 30 °C, a gradual decline in activities was noted, with complete inactivation at 60 °C. The PPO from grapes extracted with Triton-X-114 was activated with 0.2% of the ionic detergent sodium dodecyl sulfate (SDS), and exhibited maximum activities at pH 5.5 and at 30 °C. It was stable until the temperature reached 60 °C. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  16. Diploid clone produces unreduced diploid gametes but tetraploid clone generates reduced diploid gametes in the Misgurnus loach.

    PubMed

    Morishima, Kagayaki; Yoshikawa, Hiroyuki; Arai, Katsutoshi

    2012-02-01

    Most individuals of the loach Misgurnus anguillicaudatus reproduce bisexually, but cryptic clonal lineages reproduce by natural gynogenesis of unreduced diploid eggs that are genetically identical to maternal somatic cells. Triploid progeny often occur by the accidental incorporation of a sperm nucleus into diploid eggs. Sex reversal from a genetic female to a physiological male is easily induced in this species by androgen treatment and through environmental influences. Here, we produced clonal tetraploid individuals by two methods: 1) fertilization of diploid eggs from a clonal diploid female with diploid sperm of a hormonally sex-reversed clonal diploid male and 2) artificial inhibition of the release of the second polar body in eggs of clonal diploid females just after initiation of gynogenetic development. There is no genetic difference between the clonal diploid and tetraploid individuals except for the number of chromosome sets or genomes. Clonal tetraploid males never produced unreduced tetraploid sperm, only diploid sperm that were genetically identical to those of a clonal diploid. Likewise, clonal tetraploid females did not form unreduced tetraploid eggs, just diploid eggs. However, the eggs' genotypes were identical to those of the original clone, and almost all the eggs initiated natural gynogenesis. Thus, gametogenesis of the clonal tetraploid loach is controlled by the presence of two chromosome sets to pair, thereby preserving the normal meiotic process, i.e., the formation of bivalents and subsequently two successive divisions.

  17. [Analysis of the level and pattern of genomic DNA methylation in different ploidy watermelons by MSAP (Citrullus lanatus)].

    PubMed

    Wang, Chun Guo; Gu, Yu; Chen, Cheng Bin; Jiao, Ding Liang; Xue, Zhen Yi; Song, Wen Qin

    2009-04-01

    DNA methylation is one of the major epigenetic modifications. It is very important to the regulation of gene expression. In present study, an autoploidy series (2x, 3x and 4x) in watermelon (Citrullus lanatus) was constructed and MSAP (Methylation-Sensitive Amplification Polymorphism) analysis was conducted to elucidate the level and pattern of DNA methylation at CCGG sites in different ploidy watermelons. Totally, 1883 genetic loci were produced by 23 pairs of selective primers, of which 647, 655 and 581 sites were detected in diploid, autotriploid and autotetraploid, respectively. The methylation sites were 181, 150 and 159, and the corresponding total methylation ratios were 28.0%, 22.9% and 27.4% in 2x, 3x and 4x, respectively, of which the fully methylation sites were 121, 80 and 82, and the corresponding fully methylation ratios were 18.7%, 12.2% and 14.1%. Further analysis of the pattern of DNA methylation suggested that compared 4x with 2x, about half of detected sites (54.4%) shown changes of DNA methylation patterns. Similarly, compared 4x with 3x, 45.4% sites also shown changes of DNA methylation patterns. Moreover, the trend of DNA methylation adjustment mainly involved increase of DNA methylation levels in 4x. However, compared 3x with 2x or 4x, although the changes of DNA methylation pattern also widely occurred, which involved 41.6% (compared 3x with 2x) and 45.4% (compared 3x with 4x) sites, respectively, the trend of DNA methylation adjustment mainly involved decrease of DNA methylation levels in 3x. All these results indicated that DNA methylation events were widely existed in different ploidy watermelons. However, not only based on the total DNA methylation ratio or fully DNA methylation ratio, the results both implied that the DNA methylation levels were not closely associated with the autopolyploidy level in watermelon. Autotriploid watermelon shows obvious low level of DNA methylation. Analysis of DNA methylation patterns also suggested that

  18. Origin and emergence of the sweet dessert watermelon, Citrullus lanatus.

    PubMed

    Paris, Harry S

    2015-08-01

    Watermelons, Citrullus species (Cucurbitaceae), are native to Africa and have been cultivated since ancient times. The fruit flesh of wild watermelons is watery, but typically hard-textured, pale-coloured and bland or bitter. The familiar sweet dessert watermelons, C. lanatus, featuring non-bitter, tender, well-coloured flesh, have a narrow genetic base, suggesting that they originated from a series of selection events in a single ancestral population. The objective of the present investigation was to determine where dessert watermelons originated and the time frame during which sweet dessert watermelons emerged. Archaeological remains of watermelons, mostly seeds, that date from 5000 years ago have been found in northeastern Africa. An image of a large, striped, oblong fruit on a tray has been found in an Egyptian tomb that dates to at least 4000 years ago. The Greek word pepon, Latin pepo and Hebrew avattiah of the first centuries CE were used for the same large, thick-rinded, wet fruit which, evidently, was the watermelon. Hebrew literature from the end of the second century CE and Latin literature from the beginning of the sixth century CE present watermelons together with three sweet fruits: figs, table grapes and pomegranates. Wild and primitive watermelons have been observed repeatedly in Sudan and neighbouring countries of northeastern Africa. The diverse evidence, combined, indicates that northeastern Africa is the centre of origin of the dessert watermelon, that watermelons were domesticated for water and food there over 4000 years ago, and that sweet dessert watermelons emerged in Mediterranean lands by approximately 2000 years ago. Next-generation ancient-DNA sequencing and state-of-the-art genomic analysis offer opportunities to rigorously assess the relationships among ancient and living wild and primitive watermelons from northeastern Africa, modern sweet dessert watermelons and other Citrullus taxa. © The Author 2015. Published by Oxford University

  19. Origin and emergence of the sweet dessert watermelon, Citrullus lanatus

    PubMed Central

    Paris, Harry S.

    2015-01-01

    Background and Aims Watermelons, Citrullus species (Cucurbitaceae), are native to Africa and have been cultivated since ancient times. The fruit flesh of wild watermelons is watery, but typically hard-textured, pale-coloured and bland or bitter. The familiar sweet dessert watermelons, C. lanatus, featuring non-bitter, tender, well-coloured flesh, have a narrow genetic base, suggesting that they originated from a series of selection events in a single ancestral population. The objective of the present investigation was to determine where dessert watermelons originated and the time frame during which sweet dessert watermelons emerged. Key Findings Archaeological remains of watermelons, mostly seeds, that date from 5000 years ago have been found in northeastern Africa. An image of a large, striped, oblong fruit on a tray has been found in an Egyptian tomb that dates to at least 4000 years ago. The Greek word pepon, Latin pepo and Hebrew avattiah of the first centuries ce were used for the same large, thick-rinded, wet fruit which, evidently, was the watermelon. Hebrew literature from the end of the second century ce and Latin literature from the beginning of the sixth century ce present watermelons together with three sweet fruits: figs, table grapes and pomegranates. Wild and primitive watermelons have been observed repeatedly in Sudan and neighbouring countries of northeastern Africa. Conclusions The diverse evidence, combined, indicates that northeastern Africa is the centre of origin of the dessert watermelon, that watermelons were domesticated for water and food there over 4000 years ago, and that sweet dessert watermelons emerged in Mediterranean lands by approximately 2000 years ago. Next-generation ancient-DNA sequencing and state-of-the-art genomic analysis offer opportunities to rigorously assess the relationships among ancient and living wild and primitive watermelons from northeastern Africa, modern sweet dessert watermelons and other Citrullus taxa. PMID

  20. Evolutionary dynamics of diploid populations

    NASA Astrophysics Data System (ADS)

    Desimone, Ralph; Newman, Timothy

    2003-10-01

    There has been much recent interest in constructing computer models of evolutionary dynamics. Typically these models focus on asexual population dynamics, which are appropriate for haploid organsims such as bacteria. Using a recently developed ``genome template'' model, we extend the algorithm to a sexual population of diploid organisms. We will present some early results showing the temporal evolution of mean fitness and genetic variation, and compare this to typical results from haploid populations.

  1. Antitumor-promoting effects of polyphenolic extracts from seedless and seeded Indian grapes.

    PubMed

    Ramchandani, Asha G; Karibasappa, Goudar S; Pakhale, Shrirang S

    2008-01-01

    Grapes, the widely consumed fruits, are rich in polyphenols. The biological and chemopreventive activities of grape seed polyphenols have been demonstrated, while similar information regarding crude polyphenolic extracts from whole grapes and their components (pulp plus skin, seeds), particularly the seedless varieties, is lacking. Cancer chemoprevention can be achieved by inhibition of either initiation or promotion/progression stages of carcinogenesis. This study involves the determination of the polyphenolic content extracted from green (Pandhari sahebi, Thompson seedless) and black cultivars (Bangalore blue, Sharad seedless) of Indian grapes and their components (whole grapes, pulp plus skin, and seeds). Comparative evaluation of antitumor-promoting effects of seedless and seeded grape polyphenolic extracts (GPEs) was carried out in carcinogen-initiated and 12-O-tetradecanoylphorbol-13-acetate (TPA)-promoted S/RVCri-ba mouse skin and stomach, as well as esophagus of ICRC mice. The yield of crude polyphenolic extracts from whole grapes and their components varied between 3% and 51%. The total polyphenolic content expressed as mg catechin equivalents/g crude polyphenolic extract ranged from 0.47 to 701 in seeded grapes and 1.49 to 28.30 in seedless varieties. Both seedless and seeded GPEs possessed antitumor-promoting activity in target tissues of mice as is evident from their ability to delay tumor formation along with a significant decrease in tumor multiplicity and incidence. Marked and sustained epidermal hyperplasia observed in 7,12-dimethylbenz(a)anthracene-initiated and TPA-promoted mice was greatly reduced on pretreatment with GPE or catechin. The polyphenolic extracts from Sharad seedless and seeds of Bangalore blue showed the strongest suppressing activity comparable to catechin than the corresponding whole grapes. The results suggest that the chemopreventive activity of polyphenols extracted from seedless grape cultivars was as effective as that of the

  2. Grafting – a tool for managing root-knot nematodes in watermelon?

    USDA-ARS?s Scientific Manuscript database

    Wild watermelon (Citrullus lanatus var. citroides) germplasm, bottlegourd (Lagenaria siceraria) cultivars, hybrid squash (Cucurbita moschata x C. maxima), and commercial wild watermelon (C. lanatus) were evaluated as rootstocks for cultivated watermelon (C. lanatus var. lanatus) in a field infested ...

  3. Virus movement within grafted watermelon plants

    USDA-ARS?s Scientific Manuscript database

    Watermelon production in Florida is impacted by several viruses including whitefly-transmitted Squash vein yellowing virus (SqVYV), Cucurbit yellow stunting disorder virus and Cucurbit leaf crumple virus, and aphid-transmitted Papaya ringspot virus type W (PRSV-W). While germplasm resistant to some...

  4. Breeding for phytonutrient content; examples from watermelon

    USDA-ARS?s Scientific Manuscript database

    Breeding for high phytonutrient fruits and vegetables can be a fairly straightforward endeavor when the compounds of interest produce a visible effect or the methods for quantifying the compounds simple and inexpensive. Lycopene in tomatoes and watermelon is one such compound, since the amount of r...

  5. Dielectric Spectroscopy of Watermelons for Sensing Quality

    USDA-ARS?s Scientific Manuscript database

    Dielectric properties of four small-sized watermelons, grown and harvested to provide a range of maturities, were measured with an open-ended coaxial-line probe and impedance analyzer over the frequency range from 10 MHz to 1.8 GHz. Probe measurements were made on the external surface of the melons...

  6. Watermelon quality traits as affected by ploidy

    USDA-ARS?s Scientific Manuscript database

    Growers offering high quality watermelons [Citrullus lanatus (Thumb.), Matsum & Nakai] that are also high in phytonutrients will have stronger market opportunities. In order to offer highly nutritious fruit, the industry must understand the nature of phytonutrient accumulation as it is affected by ...

  7. Green-fleshed watermelon contains chlorophyll

    USDA-ARS?s Scientific Manuscript database

    Many popular and technical reports on watermelon ignore an uncommon color, green, even though mention of this color has been in the literature since 1901. However, what causes the green hue has not been reported. Since some cucurbits have chloroplasts, and chlorophyll in the flesh tissue, we surmi...

  8. Sensing Quality of Watermelons through Dielectric Permittivity

    USDA-ARS?s Scientific Manuscript database

    Dielectric properties of four small-sized watermelon cultivars, grown and harvested to provide a range of maturities, were measured with an open-ended coaxial-line probe and impedance analyzer over the frequency range from 10 MHz to 1.8 GHz. Probe measurements were made on the external surface of t...

  9. Preemergence weed control in watermelon - Lane

    USDA-ARS?s Scientific Manuscript database

    Watermelon is a major vegetable crop in Oklahoma. Weed control on this crop is crucial for commercial growers particularly as labor costs increase and availability of hoeing crews decrease. Weed infested fields can be a source of pest problems including insect and disease, in addition to the obvio...

  10. Preemergence weed control in transplanted watermelon - 2012

    USDA-ARS?s Scientific Manuscript database

    Watermelon is a major vegetable crop in Oklahoma. Effective weed control is needed to obtain good yields of marketable fruit. Chemical weed control in this crop is crucial for commercial growers, particularly as labor costs increase and availability of hoeing crews becomes less of an option. The o...

  11. Seedless Growth of Bismuth Nanowire Array via Vacuum Thermal Evaporation.

    PubMed

    Liu, Mingzhao; Nam, Chang-Yong; Zhang, Lihua

    2015-12-21

    Here a seedless and template-free technique is demonstrated to scalably grow bismuth nanowires, through thermal evaporation in high vacuum at RT. Conventionally reserved for the fabrication of metal thin films, thermal evaporation deposits bismuth into an array of vertical single crystalline nanowires over a flat thin film of vanadium held at RT, which is freshly deposited by magnetron sputtering or thermal evaporation. By controlling the temperature of the growth substrate the length and width of the nanowires can be tuned over a wide range. Responsible for this novel technique is a previously unknown nanowire growth mechanism that roots in the mild porosity of the vanadium thin film. Infiltrated into the vanadium pores, the bismuth domains (~ 1 nm) carry excessive surface energy that suppresses their melting point and continuously expels them out of the vanadium matrix to form nanowires. This discovery demonstrates the feasibility of scalable vapor phase synthesis of high purity nanomaterials without using any catalysts.

  12. Mechanism of seedlessness in a new lemon cultivar 'Xiangshui' [Citrus limon (L.) Burm. F].

    PubMed

    Zhang, Shu-Wei; Huang, Gui-Xiang; Ding, Feng; He, Xin-Hua; Pan, Jie-Chun

    2012-12-01

    Seedlessness is an important economic trait of lemon. Understanding the cellular and molecular mechanisms of seedlessness in 'Xiangshui' lemon requires detailed data on pollen and embryo sac fertility, embryo development and compatibility mechanisms governing self- and cross-pollination. The results of the current study indicate that the fertility of pollen and mature embryo sac remains normal. When flowers were self- or cross-pollinated, pollen grains of 'Xiangshui' were able to germinate on the stigma. In the case of self-pollination, pollen tubes became twisted, tube tips enlarged and tubes ruptured in the bottom of stigma. Following cross-pollination, tubes were able to grow normally in the style and ovary and enter the embryo sac, where double fertilization took place. Embryonic development resulting from cross-pollination was normal. After cross-pollination, the zygote began to divide at 2 weeks post-pollination, with early globular embryos observed after 3 weeks, globular and heart-shaped embryos at 4 weeks, torpedo-shaped embryos at 5 weeks, cotyledonary embryos at 6 weeks and thereafter germinable seeds. After self-pollination, however, ovules began to abort at 2 weeks post-pollination, with ovules disappearing at 5 weeks, ultimately producing seedless fruits. Emasculated unpollinated flowers also developed into seedless fruits, indicating that seedlessness contributes to parthenocarpy. However, gametophytic self-incompatibility has a major role in seedlessness in 'Xiangshui' lemon by blocking fertilization at the bottom of the stigma.

  13. The components of rice and watermelon root exudates and their effects on pathogenic fungus and watermelon defense

    PubMed Central

    Ren, Lixuan; Huo, Hongwei; Zhang, Fang; Hao, Wenya; Xiao, Liang; Dong, Caixia; Xu, Guohua

    2016-01-01

    ABSTRACT Watermelon (Citrullus lanatus) is susceptible to wilt disease caused by the fungus Fusarium oxysporum f. sp niveum (FON). Intercropping management of watermelon/aerobic rice (Oryza sativa) alleviates watermelon wilt disease, because some unidentified component(s) in rice root exudates suppress FON sporulation and spore germination. Here, we show that the phenolic acid p-coumaric acid is present in rice root exudates only, and it inhibits FON spore germination and sporulation. We found that exogenously applied p-coumaric acid up-regulated the expression of ClPR3 in roots, as well as increased chitinase activity in leaves. Furthermore, exogenously applied p-coumaric acid increased β-1,3-glucanase activity in watermelon roots. By contrast, we found that ferulic acid was secreted by watermelon roots, but not by rice roots, and that it stimulated spore germination and sporulation of FON. Exogenous application of ferulic acid down-regulated ClPR3 expression and inhibited chitinase activity in watermelon leaves. Salicylic acid was detected in both watermelon and rice root exudates, which stimulated FON spore germination at low concentrations and suppressed spore germination at high concentrations. Exogenously applied salicylic acid did not alter ClPR3 expression, but did increase chitinase and β-1,3-glucanase activities in watermelon leaves. Together, our results show that the root exudates of phenolic acids were different between rice and watermelon, which lead to their special ecological roles on pathogenic fungus and watermelon defense. PMID:27217091

  14. Diploid males, diploid sperm production, and triploid females in the ant Tapinoma erraticum

    NASA Astrophysics Data System (ADS)

    Cournault, Laurent; Aron, Serge

    2009-12-01

    Under complementary sex determination (CSD), females of Hymenoptera arise from diploid, fertilized eggs and males from haploid, unfertilized eggs. Incidentally, fertilized eggs that inherit two identical alleles at the CSD locus will develop into diploid males. Diploid males are usually unviable or sterile. In a few species, however, they produce diploid sperm and father a triploid female progeny. Diploid males have been reported in a number of social Hymenoptera, but the occurrence of triploid females has hardly ever been documented. Here, we report the presence of triploid females, diploid males, and diploid sperm (produced by diploid males and stored in queen spermathecae) in the ant Tapinoma erraticum. Moreover, we show variations in the frequency of triploids among female castes: Triploid females are more frequent among workers than virgin queens; they are absent among mated, reproductive queens. The frequency of triploid workers also varies between populations and between nests within populations.

  15. The height of watermelons with wall

    NASA Astrophysics Data System (ADS)

    Feierl, Thomas

    2012-03-01

    We derive asymptotics for the moments as well as the weak limit of the height distribution of watermelons with p branches with wall. This generalizes a famous result of de Bruijn et al (1972 Graph Theory and Computing (New York: Academic) pp 15-22) on the average height of planted plane trees, and results by Fulmek (2007 Electron. J. Combin. 14 R64) and Katori et al (2008 J. Stat. Phys. 131 1067-83) on the expected value and higher moments, respectively, of the height distribution of watermelons with two branches. The asymptotics for the moments depend on the analytic behaviour of certain multidimensional Dirichlet series. In order to obtain this information, we prove a reciprocity relation satisfied by the derivatives of one of Jacobi’s theta functions, which generalizes the well-known reciprocity law for Jacobi’s theta functions.

  16. Reinventing potato at the diploid level

    USDA-ARS?s Scientific Manuscript database

    The outcrossing polyploidy nature of cultivated potato has hindered the use of genomics resources to dissect the genetic basis of agronomically important traits. Reversion to the diploid level allows us to apply powerful tools toward this effort. Parthenogenesis generates diploid cultivated potato, ...

  17. Shock-Strength Determination With Seeded and Seedless Laser Methods

    NASA Technical Reports Server (NTRS)

    Herring, G. C.; Meyers, James F.

    2008-01-01

    Two nonintrusive laser diagnostics were independently used to demonstrate the measurement of time-averaged and spatially-resolved pressure change across a twodimensional (2-D) shock wave. The first method is Doppler global velocimetry (DGV) which uses water seeding and generates 2-D maps of 3-orthogonal components of velocity. A DGV-measured change in flow direction behind an oblique shock provides an indirect determination of pressure jump across the shock, when used with the known incoming Mach number and ideal shock relations (or Prandtl-Meyer flow equations for an expansion fan). This approach was demonstrated at Mach 2 on 2-D shocks and expansions generated from a flat plate at angles-of-attack approx. equals -2.4deg and +0.6deg, respectively. This technique also works for temperature jump (as well as pressure) and for normal shocks (as well as oblique). The second method, laser-induced thermal acoustics (LITA), is a seedless approach that was used to generate 1-D spatial profiles of streamwise Mach number, sound speed, pressure, and temperature across the same shock waves. Excellent agreement was obtained between the DGV and LITA methods, suggesting that either technique is viable for noninvasive shock-strength measurements.

  18. Morphological transformations of silver nanoparticles in seedless photochemical synthesis

    NASA Astrophysics Data System (ADS)

    Lu, Ya; Zhang, Congyun; Hao, Rui; Zhang, Dongjie; Fu, Yizheng; Moeendarbari, Sina; Pickering, Christopher S.; Hao, Yaowu; Liu, Yaqing

    2016-05-01

    Photochemical synthesis is an easily controlled and reliable method for the fabrication of silver (Ag) nanoparticles with various morphologies. In this work, we have systematically investigated the seedless photochemical synthesis of anisotropic Ag nanoparticles with and without PVP as surface capping agent. The time evolution of anisotropic Ag nanoparticles during the synthesis process are studied using UV-visible spectra, optical images and transmission electron microscopy. The results show that the light irradiation precisely controls the start and termination of the reaction, and the presence or absence of PVP greatly affects the morphology evolution of anisotropic Ag nanoparticles. With PVP as the surface capping agent, Ag nanoparticles grow into decahedra or prism by the deposition of Ag atoms on {111} or {110} facets through epitaxial growth. However, a different morphology evolution could happen when Ag nanoparticle is synthesized without PVP as surface capping agent. In this case, Ag nanoparticles can fuse into the decahedrons through an edge-selective particle fusion mechanism, which involves attachment, rotation and realignment of Ag nanoparticles. This process was evidenced with HRTEM images at the different stages of the transformation from Ag colloid to decahedra nanoparticles. Oriented attachment and Ostwald ripening also play important role in the transformation process.

  19. Seedless Laser Velocimetry Using Heterodyne Laser-Induced Thermal Acoustics

    NASA Technical Reports Server (NTRS)

    Hart, Roger C.; Balla, R. Jeffrey; Herring, G. C.; Jenkins, Luther N.; Bushnell, Dennis M. (Technical Monitor)

    2001-01-01

    A need exists for a seedless equivalent of laser Doppler velocimetry (LDV) for use in low-turbulence or supersonic flows or elsewhere where seeding is undesirable or impractical. A compact laser velocimeter using heterodyne non-resonant laser-induced thermal acoustics (LITA) to measure a single component of velocity is described. Neither molecular (e.g. NO2) nor particulate seed is added to the flow. In non-resonant LITA two beams split from a short-pulse pump laser are crossed; interference produces two counterpropagating sound waves by electrostriction. A CW probe laser incident on the sound waves at the proper angle is directed towards a detector. Measurement of the beating between the Doppler-shifted light and a highly attenuated portion of the probe beam allows determination of one component of flow velocity, speed of sound, and temperature. The sound waves essentially take the place of the particulate seed used in LDV. The velocimeter was used to study the flow behind a rearward-facing step in NASA Langley Research Center's Basic Aerodynamics Research Tunnel. Comparison is made with pitot-static probe data in the freestream over the range 0 m/s - 55 m/s. Comparison with LDV is made in the recirculation region behind the step and in a well-developed boundary layer in front of the step. Good agreement is found in all cases.

  20. Watermelon juice: A promising feedstock supplement, diluent, and nitrogen supplement for ethanol biofuel production

    USDA-ARS?s Scientific Manuscript database

    Processing of watermelons to produce the neutraceuticals lycopene and citrulline yields a waste stream of watermelon juice at the rate of over 500 L/Mt of watermelons. Since watermelon juice contains 7-10% readily fermentable sugars, its potential as feedstock, diluent, and nitrogen supplement was ...

  1. 7 CFR 319.56-26 - Melon and watermelon from certain countries in South America.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 5 2011-01-01 2011-01-01 false Melon and watermelon from certain countries in South... and Vegetables § 319.56-26 Melon and watermelon from certain countries in South America. (a) Cantaloupe and watermelon from Ecuador. Cantaloupe (Cucumis melo) and watermelon (fruit) (Citrullus...

  2. 7 CFR 319.56-26 - Melon and watermelon from certain countries in South America.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 5 2014-01-01 2014-01-01 false Melon and watermelon from certain countries in South... and Vegetables § 319.56-26 Melon and watermelon from certain countries in South America. (a) Cantaloupe and watermelon from Ecuador. Cantaloupe (Cucumis melo) and watermelon (fruit) (Citrullus...

  3. 7 CFR 319.56-26 - Melon and watermelon from certain countries in South America.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Melon and watermelon from certain countries in South... and Vegetables § 319.56-26 Melon and watermelon from certain countries in South America. (a) Cantaloupe and watermelon from Ecuador. Cantaloupe (Cucumis melo) and watermelon (fruit) (Citrullus...

  4. 7 CFR 319.56-26 - Melon and watermelon from certain countries in South America.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 5 2012-01-01 2012-01-01 false Melon and watermelon from certain countries in South... and Vegetables § 319.56-26 Melon and watermelon from certain countries in South America. (a) Cantaloupe and watermelon from Ecuador. Cantaloupe (Cucumis melo) and watermelon (fruit) (Citrullus...

  5. 7 CFR 1210.516 - Exemption for organic watermelons.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Exemption for organic watermelons. 1210.516 Section... SERVICE (MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE WATERMELON RESEARCH AND PROMOTION PLAN Rules and Regulations Assessments § 1210.516 Exemption for organic...

  6. 7 CFR 1210.516 - Exemption for organic watermelons.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Exemption for organic watermelons. 1210.516 Section... SERVICE (MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE WATERMELON RESEARCH AND PROMOTION PLAN Rules and Regulations Assessments § 1210.516 Exemption for organic...

  7. 7 CFR 1210.516 - Exemption for organic watermelons.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Exemption for organic watermelons. 1210.516 Section... SERVICE (MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE WATERMELON RESEARCH AND PROMOTION PLAN Rules and Regulations Assessments § 1210.516 Exemption for organic...

  8. 7 CFR 1210.516 - Exemption for organic watermelons.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Exemption for organic watermelons. 1210.516 Section... SERVICE (MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE WATERMELON RESEARCH AND PROMOTION PLAN Rules and Regulations Assessments § 1210.516 Exemption for organic...

  9. 7 CFR 1210.516 - Exemption for organic watermelons.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Exemption for organic watermelons. 1210.516 Section... SERVICE (MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE WATERMELON RESEARCH AND PROMOTION PLAN Rules and Regulations Assessments § 1210.516 Exemption for organic...

  10. Sequencing the Genome of the Heirloom Watermelon Cultivar Charleston Gray

    USDA-ARS?s Scientific Manuscript database

    The genome of the watermelon cultivar Charleston Gray, a major heirloom which has been used in breeding programs of many watermelon cultivars, was sequenced. Our strategy involved a hybrid approach using the Illumina and 454/Titanium next-generation sequencing technologies. For Illumina, shotgun g...

  11. A Rudimentary Optical System in Detecting Ripeness of Red Watermelon

    NASA Astrophysics Data System (ADS)

    Ezan Abdullah, Noor; Hashim, Hadzli; Fathullah Sulaiman, Muhammad; Korlina Madzhi, Nina; Faiz Mohd Sampian, Ahmad; Aima Ismail, Faridatul

    2015-11-01

    The purpose of this project is to detect the ripeness and quality of the watermelon particularly for red watermelon. The ripeness of the watermelon will be evaluated by using near-infrared spectroscopy sensor (NRIS). The color wavelength will classify the ripeness of the watermelon. An infrared light will be used to get the appropriate wavelength from the watermelon either from the rind or inner of it and the signal received will be analyzed. An appropriate algorithm is used to extract the information of the inner of the watermelon. A microcontroller namely Programmable Interface Controller (PIC) will be used to execute the algorithm and the result will be displayed on Liquid Crystal Display (LCD). Based on the result obtain from the device, the data is computed by using Statistical Package for the Social Sciences (SPSS). This approach is vital to verify the relationship between unripe and ripeness of red watermelon. The objective of this project is to produce an efficient system to detect the ripeness of the watermelon.

  12. Black oat cover crop management in watermelon production systems

    USDA-ARS?s Scientific Manuscript database

    Black oats (Avena strigosa Schreb.) were sown as a cover crop near Weslaco, Texas (Lat. 26 deg N) in Fall 2010. The cover crop was allowed to senesce naturally and was planted to watermelons in both the spring and in the fall of 2011. Watermelon transplants planted in the spring into mowed black o...

  13. Evolution of aroma and phenolic compounds during ripening of 'superior seedless' grapes.

    PubMed

    Hellín, Pilar; Manso, Angela; Flores, Pilar; Fenoll, José

    2010-05-26

    The evolution of aroma and phenolic compounds was studied during ripening of Vitis vinifera cv. 'Superior Seedless' grapes in two consecutive years. The major free detected compounds were citral, geraniol, and benzyl alcohol whereas geraniol, citral, nerol, citronellol, dienediol I, linalol oxide I, linalol oxide II, benzyl alcohol, and 2-phenylethanol were identified in the glycosidically bound fraction. Concentrations of the main free terpene alcohols responsible for 'Superior Seedless' aroma decreased during grape development, and bound compounds became predominant at grape maturity. Calculation of odor activity values showed that geraniol was the most active odorant followed to a lesser extent by citral and nerol. With regard to phenolic compound evolution, flavan-3-ols and flavonols were maximal at veraison and decreased throughout the ripening, stilbenes content decreased from the first stage, and total phenolics increased to show a maximum in the ripe grapes. At ripening, quercetin 3-O-glucoside and catechin were the main compounds detected in 'Superior Seedless'.

  14. Effect of phytosanitary irradiation on the postharvest quality of Seedless Kishu mandarins (Citrus kinokuni mukakukishu).

    PubMed

    Ornelas-Paz, José de Jesús; Meza, María Belén; Obenland, David; Rodríguez Friscia, Karina; Jain, Akanksha; Thornton, Shantaè; Prakash, Anuradha

    2017-09-01

    Transnational trade of 'Seedless Kishu' mandarins (Citrus kinokuni mukakukishu) would require them to be subjected to a suitable phytosanitary treatment. Irradiation is used as an effective treatment for many fruit, but the effect on quality of kishu mandarins is unknown. 'Seedless Kishu' mandarins were treated with gamma irradiation (150, 400, and 1000Gy) and stored for three weeks at 6°C and then for one week at 20°C. Irradiation at 400 and 1000Gy promoted browning of the calyx end and fungal infection. Irradiation caused immediate reductions in pulp firmness, vitamin E, individual sugars and carotenoids but increased the content of organic acids, except ascorbic acid, and phenolic compounds. The volatile profile of tested fruit was also differentially altered by irradiation. Most of these initial changes were dose dependent. 'Seedless Kishu' mandarins are significantly sensitive to irradiation and are not suitable for treatment at the studied doses. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Watermelon chlorotic stunt virus (WmCSV): a serious disease threatening watermelon production in Jordan.

    PubMed

    Al-Musa, A; Anfoka, G; Al-Abdulat, A; Misbeh, S; Haj Ahmed, F; Otri, I

    2011-08-01

    The incidence of watermelon chlorotic stunt disease and the molecular characterization of the Jordanian isolate of Watermelon chlorotic stunt virus (WmCSV-[JO]) are described in this study. Symptomatic leaf samples obtained from watermelon (Citrullus lanatus Thunb.), melon (Cucumis melo L.), squash (Cucurbita pepo), cucumber (Cucumis sativus L.), and bottle gourd (Lagenaria siceraria) plants were tested for WmCSV-[JO] infection by PCR. The virus could be detected in 8 melon and 87 watermelon samples obtained from Ghor Assafi (southern part of Jordan Valley). Three samples collected from Mafraq (eastern part of Jordan) were found mixed infected with WmCSV-[JO] and Squash leaf curl virus. The full-length DNA-A and DNA-B genomes of WmCSV-[JO] were amplified, and sequences were deposited in the GenBank under accession numbers EU561237 and EU561236, respectively. Sequence analysis reveals that WmCSV-[JO] is closely related to other virus isolates from Israel (WmCSV-[IL]), Yemen (WmCSV-[YE]), Iran (WmCSV-[IR]), Lebanon (WmCSV-[LB]), and Sudan (WmCSV-[SD]). DNA-A of WmCSV-[JO] showed highest nucleotide identity (99.42%) with WmCSV-[IL], while DNA-B had highest nucleotide identity (95.52%) with WmCSV-[YE]. Data of this study demonstrate that digestion of DNA-B genome of WmCSV isolates with ApaI enzyme can discriminate between these isolates at the molecular level. Infectious clones of WmCSV-[JO] were constructed and agroinoculated to Nicotiana benthamiana plants. Inoculated plants developed mild disease symptoms 4 weeks post inoculation, while watermelon plants biolistically inoculated with WmCSV-[JO] developed characteristic mottling, yellowing and severe leaf curling symptoms 3 weeks post inoculation.

  16. Efficient CRISPR/Cas9-based gene knockout in watermelon.

    PubMed

    Tian, Shouwei; Jiang, Linjian; Gao, Qiang; Zhang, Jie; Zong, Mei; Zhang, Haiying; Ren, Yi; Guo, Shaogui; Gong, Guoyi; Liu, Fan; Xu, Yong

    2017-03-01

    CRISPR/Cas9 system can precisely edit genomic sequence and effectively create knockout mutations in T0 generation watermelon plants. Genome editing offers great advantage to reveal gene function and generate agronomically important mutations to crops. Recently, RNA-guided genome editing system using the type II clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (Cas9) has been applied to several plant species, achieving successful targeted mutagenesis. Here, we report the genome of watermelon, an important fruit crop, can also be precisely edited by CRISPR/Cas9 system. ClPDS, phytoene desaturase in watermelon, was selected as the target gene because its mutant bears evident albino phenotype. CRISPR/Cas9 system performed genome editing, such as insertions or deletions at the expected position, in transfected watermelon protoplast cells. More importantly, all transgenic watermelon plants harbored ClPDS mutations and showed clear or mosaic albino phenotype, indicating that CRISPR/Cas9 system has technically 100% of genome editing efficiency in transgenic watermelon lines. Furthermore, there were very likely no off-target mutations, indicated by examining regions that were highly homologous to sgRNA sequences. Our results show that CRISPR/Cas9 system is a powerful tool to effectively create knockout mutations in watermelon.

  17. [Infrared spectroscopic analysis of Guilin watermelon frost products].

    PubMed

    Huang, Dong-lan; Chen, Xiao-kang; Xu, Yong-qun; Sun, Su-qin; Zhou, Qun; Lu, Wen-guan

    2012-08-01

    The objective of the present study is to analyze different products of Guilin watermelon frost by Fourier transform infrared spectroscopy (FTIR), second derivative infrared spectroscopy and two-dimensional correlation spectroscopy (2D-IR) under thermal perturbation. The structural information of the samples indicates that samples from the same factory but of different brands had some dissimilarities in the IR spectra, and the type and content of accessories of them were different compared with conventional IR spectra of samples, peaks at 638 and 616 cm(-1) all arise from anhydrous sodium sulfate in watermelon frost spray and watermelon frost capsule; the characteristic absorption peaks of the sucrose, dextrin or other accessories can be seen clearly in the spectra of watermelon frost throat-clearing buccal tablets, watermelon frost throat tablets and watermelon frost lozenge. And the IR spectra of watermelon frost lozenge is very similar to the IR spectra of sucrose, so it can be easily proved that the content of sucrose in watermelon frost lozenge is high. In the 2D-IR correlation spectra, the samples presented the differences in the position, number and relative intensity of autopeaks and correlation peak clusters. Consequently, the macroscopical fingerprint characters of FTIR, second derivative infrared spectra and 2D-IR spectra can not only provide the information about main chemical constituents in medical materials, but also analyze and identify the type and content of accessories in Guilin watermelon frost. In conclusion, the multi-steps IR macro-fingerprint method is rapid, effective, visual and accurate for pharmaceutical research.

  18. Length tunable penta-twinned palladium nanorods: seedless synthesis and electrooxidation of formic acid.

    PubMed

    Tang, Yongan; Edelmann, Richard E; Zou, Shouzhong

    2014-06-07

    Palladium nanorods with controlled lengths from 100 to 500 nm and a fixed width of 20 nm were synthesized for the first time by a seedless approach. These rods show higher peak current densities than Pd cubes for formic acid oxidation and the catalytic activity decreases with increasing rod length.

  19. Seedless fruits and the disruption of a conserved genetic pathway in angiosperm ovule development

    PubMed Central

    Lora, Jorge; Hormaza, José I.; Herrero, María; Gasser, Charles S.

    2011-01-01

    Although the biological function of fruiting is the production and dissemination of seeds, humans have developed seedless fruits in a number of plant species to facilitate consumption. Here we describe a unique spontaneous seedless mutant (Thai seedless; Ts) of Annona squamosa (sugar apple), a member of the early-divergent magnoliid angiosperm clade. Ovules (seed precursors) of the mutant lack the outer of two normal integuments, a phenocopy of the inner no outer (ino) mutant of Arabidopsis thaliana. Cloning of the INO ortholog from A. squamosa confirmed conservation of the outer integument-specific expression pattern of this gene between the two species. All regions of the gene were detectable in wild-type A. squamosa and in other members of this genus. However, no region of the INO gene could be detected in Ts plants, indicating apparent deletion of the INO locus. These results provide a case of a candidate gene approach revealing the apparent molecular basis of a useful agronomic trait (seedless fruit) in a crop species, and indicate conservation of the role of a critical regulator of ovule development between eudicots and more ancient lineages of angiosperms. The outer integument is one synapomorphy of angiosperms separating them from other extant seed plants, and the results suggest that the evolution of this structure was contemporaneous with the derivation of INO from ancestral YABBY genes. Thus, a unique lateral structure appears to have coevolved with a novel gene family member essential for the structure's formation. PMID:21402944

  20. Effect of phytosanitary irradiation on the postharvest quality of Seedless Kishu mandarins (Citrus kinokuni mukakukishu)

    USDA-ARS?s Scientific Manuscript database

    Seedless Kishu’ mandarins (Citrus kinokuni mukakukishu) were treated with gamma irradiation at 150, 400, or 1000 Gy and stored for three weeks at 6°C and then for one week at 20°C to simulate commercial handling and marketing. The quality of the fruit was then evaluated following storage using non-...

  1. Seedless fruits and the disruption of a conserved genetic pathway in angiosperm ovule development.

    PubMed

    Lora, Jorge; Hormaza, José I; Herrero, María; Gasser, Charles S

    2011-03-29

    Although the biological function of fruiting is the production and dissemination of seeds, humans have developed seedless fruits in a number of plant species to facilitate consumption. Here we describe a unique spontaneous seedless mutant (Thai seedless; Ts) of Annona squamosa (sugar apple), a member of the early-divergent magnoliid angiosperm clade. Ovules (seed precursors) of the mutant lack the outer of two normal integuments, a phenocopy of the inner no outer (ino) mutant of Arabidopsis thaliana. Cloning of the INO ortholog from A. squamosa confirmed conservation of the outer integument-specific expression pattern of this gene between the two species. All regions of the gene were detectable in wild-type A. squamosa and in other members of this genus. However, no region of the INO gene could be detected in Ts plants, indicating apparent deletion of the INO locus. These results provide a case of a candidate gene approach revealing the apparent molecular basis of a useful agronomic trait (seedless fruit) in a crop species, and indicate conservation of the role of a critical regulator of ovule development between eudicots and more ancient lineages of angiosperms. The outer integument is one synapomorphy of angiosperms separating them from other extant seed plants, and the results suggest that the evolution of this structure was contemporaneous with the derivation of INO from ancestral YABBY genes. Thus, a unique lateral structure appears to have coevolved with a novel gene family member essential for the structure's formation.

  2. Evolution of haploid-diploid life cycles when haploid and diploid fitnesses are not equal.

    PubMed

    Scott, Michael F; Rescan, Marie

    2017-02-01

    Many organisms spend a significant portion of their life cycle as haploids and as diploids (a haploid-diploid life cycle). However, the evolutionary processes that could maintain this sort of life cycle are unclear. Most previous models of ploidy evolution have assumed that the fitness effects of new mutations are equal in haploids and homozygous diploids, however, this equivalency is not supported by empirical data. With different mutational effects, the overall (intrinsic) fitness of a haploid would not be equal to that of a diploid after a series of substitution events. Intrinsic fitness differences between haploids and diploids can also arise directly, for example because diploids tend to have larger cell sizes than haploids. Here, we incorporate intrinsic fitness differences into genetic models for the evolution of time spent in the haploid versus diploid phases, in which ploidy affects whether new mutations are masked. Life-cycle evolution can be affected by intrinsic fitness differences between phases, the masking of mutations, or a combination of both. We find parameter ranges where these two selective forces act and show that the balance between them can favor convergence on a haploid-diploid life cycle, which is not observed in the absence of intrinsic fitness differences.

  3. Squash vein yellowing virus affecting watermelon in Puerto Rico

    USDA-ARS?s Scientific Manuscript database

    In this study, we report the first detection of Squash vein yellowing virus (SqVYV)-induced watermelon vine decline outside of the continental U.S. This has implications for management of cucurbit virus diseases throughout the Caribbean....

  4. Diploid hybrid speciation in Penstemon (Scrophulariaceae)

    PubMed Central

    Wolfe, Andrea D.; Xiang, Qiu-Yun; Kephart, Susan R.

    1998-01-01

    Hybrid speciation has played a significant role in the evolution of angiosperms at the polyploid level. However, relatively little is known about the importance of hybrid speciation at the diploid level. Two species of Penstemon have been proposed as diploid hybrid derivatives based on morphological data, artificial crossing studies, and pollinator behavior observations: Penstemon spectabilis (derived from hybridization between Penstemon centranthifolius and Penstemon grinnellii) and Penstemon clevelandii (derived from hybridization between P. centranthifolius and P. spectabilis). Previous studies were inconclusive regarding the purported hybrid nature of these species because of a lack of molecular markers sufficient to differentiate the parental taxa in the hybrid complex. We developed hypervariable nuclear markers using inter-simple sequence repeat banding patterns to test these classic hypotheses of diploid hybrid speciation in Penstemon. Each species in the hybrid complex was genetically distinct, separated by 10–42 species-specific inter-simple sequence repeat markers. Our data do not support the hybrid origin of P. spectabilis but clearly support the diploid hybrid origin of P. clevelandii. Our results further suggest that the primary reason diploid hybrid speciation is so difficult to detect is the lack of molecular markers able to differentiate parental taxa from one another, particularly with recently diverged species. PMID:9560237

  5. Physiological investigation of gold nanorods toward watermelon.

    PubMed

    Wan, Yujie; Li, Junli; Ren, Hongxuan; Huang, Jin; Yuan, Hong

    2014-08-01

    The objective of the present study was to evaluate the phytotoxicity and oxidant stress of the gold nanorods toward watermelon, and hence give a quantitative risk assessment of both seeds and plants phase. The seed germination, the activity of antioxidant enzymes, and the contents of soluble protein and malondialdehyde (MDA) have been measured while the plant roots were observed by transmission electron microscopy (TEM). It was found that the gold nanorods significantly promoted the root elongation. Furthermore, the results on the enzymes activities of plant indicated that oxidative stress happened in the plant treated with gold nanorods. However, the gold nanorods resulted in the phytotoxicity toward plant especially at high concentration. The TEM images of the plant roots with and without the treatment of gold nanorods showed the significant different size of starch granules. In conclusion, significant physiological changes of plant occurred after treatment with the gold nanorods.

  6. Breeding for seedless grapes using Chinese wild Vitis spp. II. In vitro embryo rescue and plant development.

    PubMed

    Ji, Wei; Wang, Yuejin

    2013-12-01

    Since 1982, the embryo rescue technique has been widely applied to embryo germination of stenospermic grapes in cross-breeding programmes. This project aimed to: (1) use embryos to breed new seedless cultivars of Vitis vinifera as the female parents utilising wild Chinese Vitis spp. as the male parents; and (2) develop an efficient method for in vitro embryo rescue and plant development. Among the different genotypes, the productions of hybrid plants were significantly different, ranged from 21.1% ('Ruby Seedless' × 'Beichun') to only 1.1% ('Pink Seedless' × 'Beichun'), except for the combinations from which no surviving seedlings were obtained. We collected hybridisation fruits from 28 June to 3 August, and obtained their best sampling times described within days after flowering. The highest rates of embryo formation (24.3%) and plant development (91.4%) were found when ovules of 'Ruby Seedless' were cultured in MM4 + 500 mg L(-1) mashed banana. Seven new hybrids of V. vinifera with wild Chinese Vitis spp. were obtained. As a result of early nuclear-free character identification, 17 seedless grape lines were obtained. An efficient system of seedless grape breeding through embryo rescue was also established. © 2013 Society of Chemical Industry.

  7. Identification of SNP Haplotypes and Prospects of Association Mapping in Watermelon

    USDA-ARS?s Scientific Manuscript database

    Watermelon is the fifth most economically important vegetable crop cultivated world-wide. Implementing Single Nucleotide Polymorphism (SNP) marker technology in watermelon breeding and germplasm evaluation programs holds a key to improve horticulturally important traits. Next-generation sequencing...

  8. Utility of Grafting for Managing Southern Root-knot Nematode, Meloidogyne Incognita, in Watermelon

    USDA-ARS?s Scientific Manuscript database

    Four bottlegourd (Lagenaria siceraria) cultivars, one squash (Cucurbita moschata x C. maxima) hybrid, four wild watermelon (Citrullus lanatus var. citroides) germplasm lines, and one commercial wild watermelon (C. lanatus var. citroides) cultivar were evaluated as rootstocks for cultivated watermelo...

  9. Grafting for Management of Southern Root-knot Nematode, Meloidogyne Incognita, in Watermelon

    USDA-ARS?s Scientific Manuscript database

    Four bottlegourd (Lagenaria siceraria) cultivars, one squash (Cucurbita moschata x C. maxima) hybrid, four wild watermelon (Citrullus lanatus var. citroides) germplasm lines, and one commercial wild watermelon (C. lanatus var. citroides) cultivar were evaluated as rootstocks for cultivated watermelo...

  10. Reinventing potato at the diploid level

    USDA-ARS?s Scientific Manuscript database

    We are positioned to revolutionize potato by reconstructing it as a diploid inbred-line based crop. Currently, potato is an asexually propagated cross-pollinated tetraploid crop, for which breeding methodologies have not changed substantially in 100 years. Current methods for creating new potato cul...

  11. Diploid yeast cells yield homozygous spontaneous mutations

    NASA Technical Reports Server (NTRS)

    Esposito, M. S.; Bruschi, C. V.; Brushi, C. V. (Principal Investigator)

    1993-01-01

    A leucine-requiring hybrid of Saccharomyces cerevisiae, homoallelic at the LEU1 locus (leu1-12/leu1-12) and heterozygous for three chromosome-VII genetic markers distal to the LEU1 locus, was employed to inquire: (1) whether spontaneous gene mutation and mitotic segregation of heterozygous markers occur in positive nonrandom association and (2) whether homozygous LEU1/LEU1 mutant diploids are generated. The results demonstrate that gene mutation of leu1-12 to LEU1 and mitotic segregation of heterozygous chromosome-VII markers occur in strong positive nonrandom association, suggesting that the stimulatory DNA lesion is both mutagenic and recombinogenic. In addition, genetic analysis of diploid Leu+ revertants revealed that approximately 3% of mutations of leu1-12 to LEU1 result in LEU1/LEU1 homozygotes. Red-white sectored Leu+ colonies exhibit genotypes that implicate post-replicational chromatid breakage and exchange near the site of leu1-12 reversion, chromosome loss, and subsequent restitution of diploidy, in the sequence of events leading to mutational homozygosis. By analogy, diploid cell populations can yield variants homozygous for novel recessive gene mutations at biologically significant rates. Mutational homozygosis may be relevant to both carcinogenesis and the evolution of asexual diploid organisms.

  12. Diploid yeast cells yield homozygous spontaneous mutations

    NASA Technical Reports Server (NTRS)

    Esposito, M. S.; Bruschi, C. V.; Brushi, C. V. (Principal Investigator)

    1993-01-01

    A leucine-requiring hybrid of Saccharomyces cerevisiae, homoallelic at the LEU1 locus (leu1-12/leu1-12) and heterozygous for three chromosome-VII genetic markers distal to the LEU1 locus, was employed to inquire: (1) whether spontaneous gene mutation and mitotic segregation of heterozygous markers occur in positive nonrandom association and (2) whether homozygous LEU1/LEU1 mutant diploids are generated. The results demonstrate that gene mutation of leu1-12 to LEU1 and mitotic segregation of heterozygous chromosome-VII markers occur in strong positive nonrandom association, suggesting that the stimulatory DNA lesion is both mutagenic and recombinogenic. In addition, genetic analysis of diploid Leu+ revertants revealed that approximately 3% of mutations of leu1-12 to LEU1 result in LEU1/LEU1 homozygotes. Red-white sectored Leu+ colonies exhibit genotypes that implicate post-replicational chromatid breakage and exchange near the site of leu1-12 reversion, chromosome loss, and subsequent restitution of diploidy, in the sequence of events leading to mutational homozygosis. By analogy, diploid cell populations can yield variants homozygous for novel recessive gene mutations at biologically significant rates. Mutational homozygosis may be relevant to both carcinogenesis and the evolution of asexual diploid organisms.

  13. On the Genealogy of Asexual Diploids

    NASA Astrophysics Data System (ADS)

    Lam, Fumei; Langley, Charles H.; Song, Yun S.

    Given molecular genetic data from diploid individuals that, at present, reproduce mostly or exclusively asexually without recombination, an important problem in evolutionary biology is detecting evidence of past sexual reproduction (i.e., meiosis and mating) and recombination (both meiotic and mitotic). However, currently there is a lack of computational tools for carrying out such a study. In this paper, we formulate a new problem of reconstructing diploid genealogies under the assumption of no sexual reproduction or recombination, with the ultimate goal being to devise genealogy-based tools for testing deviation from these assumptions. We first consider the infinite-sites model of mutation and develop linear-time algorithms to test the existence of an asexual diploid genealogy compatible with the infinite-sites model of mutation, and to construct one if it exists. Then, we relax the infinite-sites assumption and develop an integer linear programming formulation to reconstruct asexual diploid genealogies with the minimum number of homoplasy (back or recurrent mutation) events. We apply our algorithms on simulated data sets with sizes of biological interest.

  14. Length tunable penta-twinned palladium nanorods: seedless synthesis and electrooxidation of formic acid

    NASA Astrophysics Data System (ADS)

    Tang, Yongan; Edelmann, Richard E.; Zou, Shouzhong

    2014-05-01

    Palladium nanorods with controlled lengths from 100 to 500 nm and a fixed width of 20 nm were synthesized for the first time by a seedless approach. These rods show higher peak current densities than Pd cubes for formic acid oxidation and the catalytic activity decreases with increasing rod length.Palladium nanorods with controlled lengths from 100 to 500 nm and a fixed width of 20 nm were synthesized for the first time by a seedless approach. These rods show higher peak current densities than Pd cubes for formic acid oxidation and the catalytic activity decreases with increasing rod length. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr00299g

  15. Seedless clustering in all-sky searches for gravitational-wave transients

    NASA Astrophysics Data System (ADS)

    Thrane, Eric; Coughlin, Michael

    2014-03-01

    The problem of searching for unmodeled gravitational-wave bursts can be thought of as a pattern recognition problem: how to find statistically significant clusters in spectrograms of strain power when the precise signal morphology is unknown. In a previous publication, we showed how "seedless clustering" can be used to dramatically improve the sensitivity of searches for long-lived (˜10-1000 s) gravitational-wave transients. To manage the computational costs, this initial analysis focused on externally triggered searches where the source location and emission time are both known to some degree of precision. In this paper, we show how the principle of seedless clustering can be extended to facilitate computationally feasible, all-sky searches where the direction and emission time of the source are entirely unknown. We further demonstrate that it is possible to achieve a considerable reduction in computation time by using graphical processor units, thereby facilitating more sensitive searches.

  16. Evaluation of virus resistant rootstocks to manage watermelon vine decline and diseases caused by other potyviruses

    USDA-ARS?s Scientific Manuscript database

    Watermelon vine decline caused by Squash vein yellowing virus (SqVYV) is an emerging disease that has caused severe losses to Florida watermelon growers in recent years. Papaya ringspot virus type W (PRSV-W) is one of several watermelon-infecting potyviruses long present in the southeastern U.S. L...

  17. 7 CFR 1210.521 - Reports of disposition of exempted watermelons.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Reports of disposition of exempted watermelons. 1210... WATERMELON RESEARCH AND PROMOTION PLAN Rules and Regulations Assessments § 1210.521 Reports of disposition of exempted watermelons. The Board may require reports by handlers or importers on the handling/importing and...

  18. 7 CFR 1210.521 - Reports of disposition of exempted watermelons.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Reports of disposition of exempted watermelons. 1210... WATERMELON RESEARCH AND PROMOTION PLAN Rules and Regulations Assessments § 1210.521 Reports of disposition of exempted watermelons. The Board may require reports by handlers or importers on the handling/importing and...

  19. 7 CFR 1210.521 - Reports of disposition of exempted watermelons.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Reports of disposition of exempted watermelons. 1210... WATERMELON RESEARCH AND PROMOTION PLAN Rules and Regulations Assessments § 1210.521 Reports of disposition of exempted watermelons. The Board may require reports by handlers or importers on the handling/importing and...

  20. 7 CFR 1210.521 - Reports of disposition of exempted watermelons.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Reports of disposition of exempted watermelons. 1210... WATERMELON RESEARCH AND PROMOTION PLAN Rules and Regulations Assessments § 1210.521 Reports of disposition of exempted watermelons. The Board may require reports by handlers or importers on the handling/importing and...

  1. 7 CFR 1210.521 - Reports of disposition of exempted watermelons.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Reports of disposition of exempted watermelons. 1210... WATERMELON RESEARCH AND PROMOTION PLAN Rules and Regulations Assessments § 1210.521 Reports of disposition of exempted watermelons. The Board may require reports by handlers or importers on the handling/importing and...

  2. 76 FR 25619 - Watermelon Research and Promotion Plan; Redistricting and Importer Representation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-05

    ... Agricultural Marketing Service 7 CFR Part 1210 Watermelon Research and Promotion Plan; Redistricting and... proposed rule invites comments on changing the boundaries of all seven districts under the Watermelon... National Watermelon Promotion Board (Board). In addition, the Board is adding two importer seats based...

  3. Impact of five cover crop green manures and Actinovate on Fusarium Wilt of watermelon

    USDA-ARS?s Scientific Manuscript database

    Triploid watermelon cultivars are grown on more than 2,023 ha in Maryland and in Delaware. Triploid watermelons have little host resistance to Fusarium wilt of watermelon (Fusarium oxysporum f. sp. niveum). The effects of four different fall-planted cover crops that were tilled in the spring as gree...

  4. 78 FR 64408 - Watermelon Research and Promotion Plan; Importer Membership Requirements and Referendum Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-29

    ...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 1210 Watermelon Research and Promotion... Watermelon Research and Promotion Plan (Plan) importer membership requirements to serve on the National Watermelon Promotion Board (Board). The Board recommended eliminating the requirement that an importer...

  5. 78 FR 10104 - Watermelon Research and Promotion Plan; Importer Membership Requirements

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-13

    ...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 1210 Watermelon Research and Promotion... rule. SUMMARY: This rule proposes to amend the Watermelon Research and Promotion Plan (Plan) importer membership requirements to serve on the National Watermelon Promotion Board (Board). The Board recommended...

  6. 76 FR 42009 - Watermelon Research and Promotion Plan; Redistricting and Importer Representation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-18

    ... Agricultural Marketing Service 7 CFR Part 1210 Watermelon Research and Promotion Plan; Redistricting and... changes the boundaries of all seven districts under the Watermelon Research and Promotion Plan (Plan) to reapportion the producer, handler, and importer memberships on the National Watermelon Promotion Board...

  7. Isolation and genetic mapping of NBS-LRR disease resistance gene analogs in watermelon

    USDA-ARS?s Scientific Manuscript database

    Sixty-six watermelon disease resistance gene analogs (WRGA) were isolated from genotypes possessing disease resistance to fusarium oxysporum f. sp. niveum races 0, 1, and 2, zucchini yellow mosaic virus, papaya ringspot virus watermelon strain, cucumber mosaic virus, and watermelon mosaic virus. Deg...

  8. Searching for gravitational-wave transients with a qualitative signal model: Seedless clustering strategies

    NASA Astrophysics Data System (ADS)

    Thrane, Eric; Coughlin, Michael

    2013-10-01

    Gravitational-wave bursts are observable as bright clusters of pixels in spectrograms of strain power. Clustering algorithms can be used to identify candidate gravitational-wave events. Clusters are often identified by grouping together seed pixels in which the power exceeds some threshold. If the gravitational-wave signal is long-lived, however, the excess power may be spread out over many pixels, none of which are bright enough to become seeds. Without seeds, the problem of detection through clustering becomes more complicated. In this paper, we investigate seedless clustering algorithms in searches for long-lived narrow-band gravitational-wave bursts. Using four astrophysically motivated test waveforms, we compare a seedless clustering algorithm to two algorithms using seeds. We find that the seedless algorithm can detect gravitational-wave signals (at a fixed false-alarm and false-dismissal rate) at distances between 1.5-2× those achieved with the seed-based clustering algorithms, corresponding to significantly increased detection volumes: 4.2-7.4×. This improvement in sensitivity may extend the reach of second-generation detectors such as Advanced LIGO and Advanced Virgo deeper into astrophysically interesting distances.

  9. Fruit quality assessment of watermelons grafted onto citron melon rootstock.

    PubMed

    Fredes, Alejandro; Roselló, Salvador; Beltrán, Joaquim; Cebolla-Cornejo, Jaime; Pérez-de-Castro, Ana; Gisbert, Carmina; Picó, María Belén

    2017-03-01

    The grafting of watermelons (Citrullus lanatus) is a common technique that increases yield under stressful soil conditions. The most common rootstocks for watermelons are Cucurbita hybrids. However, they often have a negative impact on fruit quality. Exploiting novel Citrullus germplasm such as citron melon (Citrullus lanatus var. citroides) is an alternative to avoid these quality problems. Citron melon has been validated as watermelon rootstock, comparing its effects on watermelon quality to those of Cucurbita hybrids. Larger fruits with thicker rinds were observed in fruits from plants grafted onto both citron and Cucurbita rootstocks. The citron melon had no significant effect on flesh sugars or acid profiles compared to non-grafted watermelons, except for an increase in glucose and malic acid content, which also occurred in the Cucurbita rootstocks. The aroma profile of fruits produced on citron melon was similar to that of the non-grafted and self-grafted controls. The citron rootstock did not display the increased levels of (Z)-6-nonen-1-ol (a compound associated with pumpkin-like odors) found in fruits produced with Cucurbita hybrids. The low impact of citron melon rootstock on fruit quality, along with the enhanced resistance against nematodes, make the citron a promising alternative to Cucurbita rootstocks. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  10. Inheritance of resistance to zucchini yellow mosaic virus and watermelon mosaic virus in watermelon.

    PubMed

    Xu, Y; Kang, D; Shi, Z; Shen, H; Wehner, T

    2004-01-01

    High resistance to zucchini yellow mosaic virus-China strain (ZYMV-CH) and moderate resistance to watermelon mosaic virus (WMV) were found in a selection of PI 595203 (Citrullus lanatus var. lanatus), an Egusi type originally collected in Nigeria. Mixed inoculations showed primarily that these two viruses have no cross-protection. This fact may explain the high frequency of mixed infection often observed in commercial fields. When plants were inoculated with a mixture of the two viruses, the frequency of plants resistant to ZYMV was lower than expected, indicating that WMV infection may reduce the ability of a plant to resist ZYMV. We studied inheritance of resistance to ZYMV-CH and WMV, using crosses between a single-plant selection of PI 595203 and the ZYMV-susceptible watermelon inbreds 9811 and 98R. According to virus ratings of the susceptible parents, the resistant parent, and the F1, F2, and BC1 generations, resistance to ZYMV-CH was conferred by a single recessive gene, for which the symbol zym-CH is suggested. The high tolerance to WMV was controlled by at least two recessive genes.

  11. Dielectric spectroscopy of watermelons for quality sensing

    NASA Astrophysics Data System (ADS)

    Nelson, Stuart O.; Guo, Wen-chuan; Trabelsi, Samir; Kays, Stanley J.

    2007-07-01

    Dielectric properties of four small-sized watermelon cultivars, grown and harvested to provide a range of maturities, were measured with an open-ended coaxial-line probe and an impedance analyser over the frequency range from 10 MHz to 1.8 GHz. Probe measurements were made on the external surface of the melons and also on tissue samples from the edible internal tissue. Moisture content and soluble solids content (SSC) were measured for internal tissue samples, and SSC (sweetness) was used as the quality factor for correlation with the dielectric properties. Individual dielectric constant and loss factor correlations with SSC were low, but a high correlation was obtained between the SSC and permittivity from a complex-plane plot of dielectric constant and loss factor, each divided by SSC. However, SSC prediction from the dielectric properties by this relationship was not as high as expected (coefficient of determination about 0.4). Permittivity data (dielectric constant and loss factor) for the melons are presented graphically to show their relationships with frequency for the four melon cultivars and for external surface and internal tissue measurements. A dielectric relaxation for the external surface measurements, which may be attributable to a combination of bound water, Maxwell-Wagner, molecular cluster or ion-related effects, is also illustrated. Coefficients of determination for complex-plane plots, moisture content and SSC relationship, and penetration depth are also shown graphically. Further studies are needed for determining the practicality of sensing melon quality from their dielectric properties.

  12. Analysis and residue levels of forchlorfenuron (CPPU) in watermelons.

    PubMed

    Valverde, Antonio; Piedra, Luis; Aguilera, Ana; Boulaid, Mourad; Camacho, Francisco

    2007-01-01

    This paper describes the application of liquid chromatography-tandem mass spectrometry (LC/MS-MS) for analysis of residues of forchlorfenuron (CPPU), a new plant growth regulator, in watermelons, after a sample preparation step based on the buffered Quick, Easy, Cheap, Effective, Rugged and Safe extraction method. Analytical determinations were carried out in a triple quadrupole system fitted with an electrospray interphase operating in the positive ionisation mode (ESI+). Three simultaneous MS-MS transitions of the quasi-molecular ion m/z 248 (precursor ion) were monitored for data acquisition (248 > 129, 248 > 155, and 248 > 248), using the transition 248 > 129 for quantitation. Recovery studies on watermelons at levels of 1-200 microg/kg, performing five replicates at each level and using bracketing single-level calibration with matrix-matched standards for quantitation, gave forchlorfenuron mean recoveries ranging from 82 to 106% with relative standard deviations (RSD) lower than 18%. The limit of determination was established at 1 microg/kg. The method was applied to evaluate the persistence of forchlorfenuron residues in watermelons grown in plastic greenhouses, after applying an individual spray treatment to the flower ovary at the anthesis stage (45 mu g/flower and 60 mu g/flower for cv "Extazy" and cv "reina de corazones" watermelons, respectively). One month after treatment, 20 "Extazy" watermelon units (1.5-2 kg/unit) and 20 "Reina de corazones" watermelon units (4-5 kg/unit) were collected and analyzed individually. None of the samples contained forchlorfenuron residues higher than 1 microg/kg.

  13. Evolution by fisherian sexual selection in diploids.

    PubMed

    Greenspoon, Philip B; Otto, Sarah P

    2009-04-01

    Most models of Fisherian sexual selection assume haploidy. However, analytical models that focus on dynamics near fixation boundaries and simulations show that the resulting behavior depends on ploidy. Here we model sexual selection in a diploid to characterize behaviour away from fixation boundaries. The model assumes two di-allelic loci, a male-limited trait locus subject to viability selection, and a preference locus that determines a female's tendency to mate with males based on their genotype at the trait locus. Using a quasi-linkage equilibrium (QLE) approach, we find a general equation for the curves of quasi-neutral equilibria, and the conditions under which they are attracting or repelling. Unlike in the haploid model, the system can move away from the internal curve of equilibria in the diploid model. We show that this is the case when the combined forces of natural and sexual selection induce underdominance at the trait locus.

  14. Direct determination of diploid genome sequences

    PubMed Central

    Weisenfeld, Neil I.; Kumar, Vijay; Shah, Preyas; Church, Deanna M.; Jaffe, David B.

    2017-01-01

    Determining the genome sequence of an organism is challenging, yet fundamental to understanding its biology. Over the past decade, thousands of human genomes have been sequenced, contributing deeply to biomedical research. In the vast majority of cases, these have been analyzed by aligning sequence reads to a single reference genome, biasing the resulting analyses, and in general, failing to capture sequences novel to a given genome. Some de novo assemblies have been constructed free of reference bias, but nearly all were constructed by merging homologous loci into single “consensus” sequences, generally absent from nature. These assemblies do not correctly represent the diploid biology of an individual. In exactly two cases, true diploid de novo assemblies have been made, at great expense. One was generated using Sanger sequencing, and one using thousands of clone pools. Here, we demonstrate a straightforward and low-cost method for creating true diploid de novo assemblies. We make a single library from ∼1 ng of high molecular weight DNA, using the 10x Genomics microfluidic platform to partition the genome. We applied this technique to seven human samples, generating low-cost HiSeq X data, then assembled these using a new “pushbutton” algorithm, Supernova. Each computation took 2 d on a single server. Each yielded contigs longer than 100 kb, phase blocks longer than 2.5 Mb, and scaffolds longer than 15 Mb. Our method provides a scalable capability for determining the actual diploid genome sequence in a sample, opening the door to new approaches in genomic biology and medicine. PMID:28381613

  15. Functional rare males in diploid parthenogenetic Artemia.

    PubMed

    Maccari, M; Gómez, A; Hontoria, F; Amat, F

    2013-09-01

    Functional males that are produced occasionally in some asexual taxa - called 'rare males' - raise considerable evolutionary interest, as they might be involved in the origin of new parthenogenetic lineages. Diploid parthenogenetic Artemia produce rare males, which may retain the ability to mate with females of related sexual lineages. Here, we (i) describe the frequency of male progeny in populations of diploid parthenogenetic Artemia, (ii) characterize rare males morphologically, (iii) assess their reproductive role, using cross-mating experiments with sexual females of related species from Central Asia and characterize the F1 hybrid offspring viability and (iv) confirm genetically both the identity and functionality of rare males using DNA barcoding and microsatellite loci. Our result suggests that these males may have an evolutionary role through genetic exchange with related sexual species and that diploid parthenogenetic Artemia is a good model system to investigate the evolutionary transitions between sexual species and parthenogenetic strains. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

  16. The Height and Range of Watermelons without Wall

    NASA Astrophysics Data System (ADS)

    Feierl, Thomas

    We determine the weak limit of the distribution of the random variables "height" and "range" on the set of p-watermelons without wall restriction as the number of steps tends to infinity. Additionally, we provide asymptotics for the moments of the random variable "height".

  17. Evaluation of Reflex (fomesafen) herbicide for watermelon in Oklahoma

    USDA-ARS?s Scientific Manuscript database

    Effective preemergence herbicides are needed for weed control in watermelon grown from transplants. Reflex (fomesafen) was found to be effective and to exhibit crop safety in southeast USA. Trials were conducted during 2011 and 2012 in southeast Oklahoma to determine if this product would be useful...

  18. Crown blight of melons and crown decline of watermelon

    USDA-ARS?s Scientific Manuscript database

    The cucurbits (family Cucurbitaceae) form a diverse group of species grown around the world under many different conditions and for many different purposes. The major cultivated types include cucumber, melon (cantaloupe or muskmelon, honeydew, etc.), watermelon, squash, and pumpkin. Minor cultivated...

  19. Permittivities of watermelon pulp and juice and correlation with quality.

    USDA-ARS?s Scientific Manuscript database

    Permittivities from 10 to 4500 MHz at 24 'C were measured on pulp and juice of watermelons of different maturities with an open-ended coaxial-line probe and network analyzer. The dielectric constant of both materials decreased monotonically with increasing frequency and loss factor had minimum at ab...

  20. L-citrulline levels in watermelon cultivars from three locations

    USDA-ARS?s Scientific Manuscript database

    Producers of fresh fruit and vegetables face increasing production costs and more intense international market competition. Maximizing marketability by offering high quality produce that is also highly nutritious gives new market niches for some crops, such as watermelons, if appropriate germplasm ...

  1. Organic weed control in certified organic watermelon production

    USDA-ARS?s Scientific Manuscript database

    The increasing perception by consumers that organic food tastes better and is healthier continues to expand the demand for organically produced crops. Field research was conducted in southeast Oklahoma to determine the impact of organic production systems on weed control and watermelon (Citrullus l...

  2. Root-knot nematode resistant rootstocks for grafted watermelon

    USDA-ARS?s Scientific Manuscript database

    Rootstock lines of wild watermelon (Citrullus lanatus var. citroides) with resistance to root-knot nematodes (RKN) were developed by our team at the U.S. Vegetable Laboratory. Rootstock lines RKVL 301, RKVL 316, and RKVL 318 (RKVL = Root Knot Vegetable Laboratory) were compared to wild tinda (Praec...

  3. Tolerance to Phytophthora Fruit Rot in Watermelon Plant Introductions

    USDA-ARS?s Scientific Manuscript database

    Phytophthora capsici is distributed worldwide, and is an aggressive pathogen with a broad host range infecting solanaceous, leguminaceous, and cucurbitaceous crops. Fruit rot, caused by P. capsici is an emerging disease in most watermelon producing regions of Southeast US. Resistance to fruit rot o...

  4. Whiteflies: Developing host plant resistance in watermelon from wild sources

    USDA-ARS?s Scientific Manuscript database

    The whitefly (Aleyrodidae) Bemisia tabaci causes serious damage to horticultural crops, including watermelon (Citrullus lanatus var. lanatus) and it is known to transmit many plant viruses. This whitefly is highly polyphagous, with over 1,000 known species, and can adapt to the environment. Yet, th...

  5. Developing resistance for watermelon against whiteflies (Hemiptera: Aleyrodidae)

    USDA-ARS?s Scientific Manuscript database

    Host plant resistance is a fundamental component of crop sustainability. The sweetpotato whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae), is a key pest of many crops around the world. It is adaptive to its environment and feeds on an impressive (over 1,000) number of plant species. Watermelon (Cit...

  6. Dietectric Properties of Watermelons & Correlation with Soluble Solids Content

    USDA-ARS?s Scientific Manuscript database

    Technical Abstract Dielectric properties of four small-sized watermelon cultivars, grown and harvested to provide a range of maturities, were measured with an open-ended coaxial-line probe and impedance analyzer over the frequency range from 10 MHz to 1.8 GHz. Probe measurements were made on the e...

  7. Dielectric Properties of Watermelons and Correlation with Soluble Solids Content

    USDA-ARS?s Scientific Manuscript database

    Dielectric properties of four small-sized watermelon cultivars, grown and harvested to provide a range of maturities, were measured with an open-ended coaxial-line probe and impedance analyzer over the frequency range from 10 MHz to 1.8 GHz. Probe measurements were made on the external surface of t...

  8. Effects of ambient oxidant air pollution in the San Joaquin Valley on Thompson seedless grapes

    SciTech Connect

    Brewer, R.F.; Ashcroft, R.

    1984-01-01

    Mature Thompson seedless grape vines were enclosed in specially constructed plastic covered chambers supplied with carbon filtered and non-filtered (ambient) air from time of bud break through leaf drop. Effects on vegetative growth and fruiting were determined for three seasons. No effects on fruit production were measured the first season after covering but vegetative growth increased 12% in chambers supplied with filtered air. By the third season fruit yields were 27.5% higher in the filtered as compared with ambient chambers. The only visible symptoms associated with exposure to the oxidants was accelerated senescence which appeared 3 weeks to 1 month earlier on vines receiving ambient or nonfiltered air.

  9. Common-Path Heterodyne Laser-Induced Thermal Acoustics for Seedless Laser Velocimetry

    NASA Technical Reports Server (NTRS)

    Hart, Roger C.; Herring, G. C.; Balla, R. Jeffrey; Bushnell, Dennis M. (Technical Monitor)

    2001-01-01

    We demonstrate the use of a novel technique for the detection of heterodyne laser-induced thermal acoustics signals, which allows the construction of a highly stable seedless laser velocimeter. A common-path configuration is combined with quadrature detection to provide flow direction, greatly improve robustness to misalignment and vibration, and give reliable velocity measurement at low flow velocities. Comparison with Pitot tube measurements in the freestream of a wind tunnel shows root-mean-square errors of 0.67 m/s over the velocity range 0.55 m/s.

  10. Utilizing genetic diversity in the desert watermelon citrullus colocynthis for enhancing watermelon cultivars for resistance to biotic and abiotic stress

    USDA-ARS?s Scientific Manuscript database

    Wide genetic diversity exists among the desert watermelon Citrullus colocynthis (L.) Schrad. (CC) accessions collected in the deserts of northern Africa, the Middle East, and Asia. Because of their resistance to biotic and abiotic stresses, there can be a viable source of genes used for enhancing wa...

  11. The evolution of haploid, diploid and polymorphic haploid-diploid life cycles: the role of meiotic mutation.

    PubMed

    Hall, D W

    2000-10-01

    Here I present a simple population genetic model to investigate the evolution of polymorphic haploid-diploid life cycles. The key feature of the model is the assumption of mutation occurring during meiosis. I show that, in addition to regions favoring haploid or diploid life cycles, there are substantial regions of the parameter space under which polymorphic haploid-diploid life cycles are expected to evolve.

  12. The draft genome of watermelon (Citrullus lanatus) and resequencing of 20 diverse accessions.

    PubMed

    Guo, Shaogui; Zhang, Jianguo; Sun, Honghe; Salse, Jerome; Lucas, William J; Zhang, Haiying; Zheng, Yi; Mao, Linyong; Ren, Yi; Wang, Zhiwen; Min, Jiumeng; Guo, Xiaosen; Murat, Florent; Ham, Byung-Kook; Zhang, Zhaoliang; Gao, Shan; Huang, Mingyun; Xu, Yimin; Zhong, Silin; Bombarely, Aureliano; Mueller, Lukas A; Zhao, Hong; He, Hongju; Zhang, Yan; Zhang, Zhonghua; Huang, Sanwen; Tan, Tao; Pang, Erli; Lin, Kui; Hu, Qun; Kuang, Hanhui; Ni, Peixiang; Wang, Bo; Liu, Jingan; Kou, Qinghe; Hou, Wenju; Zou, Xiaohua; Jiang, Jiao; Gong, Guoyi; Klee, Kathrin; Schoof, Heiko; Huang, Ying; Hu, Xuesong; Dong, Shanshan; Liang, Dequan; Wang, Juan; Wu, Kui; Xia, Yang; Zhao, Xiang; Zheng, Zequn; Xing, Miao; Liang, Xinming; Huang, Bangqing; Lv, Tian; Wang, Junyi; Yin, Ye; Yi, Hongping; Li, Ruiqiang; Wu, Mingzhu; Levi, Amnon; Zhang, Xingping; Giovannoni, James J; Wang, Jun; Li, Yunfu; Fei, Zhangjun; Xu, Yong

    2013-01-01

    Watermelon, Citrullus lanatus, is an important cucurbit crop grown throughout the world. Here we report a high-quality draft genome sequence of the east Asia watermelon cultivar 97103 (2n = 2× = 22) containing 23,440 predicted protein-coding genes. Comparative genomics analysis provided an evolutionary scenario for the origin of the 11 watermelon chromosomes derived from a 7-chromosome paleohexaploid eudicot ancestor. Resequencing of 20 watermelon accessions representing three different C. lanatus subspecies produced numerous haplotypes and identified the extent of genetic diversity and population structure of watermelon germplasm. Genomic regions that were preferentially selected during domestication were identified. Many disease-resistance genes were also found to be lost during domestication. In addition, integrative genomic and transcriptomic analyses yielded important insights into aspects of phloem-based vascular signaling in common between watermelon and cucumber and identified genes crucial to valuable fruit-quality traits, including sugar accumulation and citrulline metabolism.

  13. Comparative transcript profiling of gene expression between seedless Ponkan mandarin and its seedy wild type during floral organ development by suppression subtractive hybridization and cDNA microarray.

    PubMed

    Qiu, Wen-Ming; Zhu, An-Dan; Wang, Yao; Chai, Li-Jun; Ge, Xiao-Xia; Deng, Xiu-Xin; Guo, Wen-Wu

    2012-08-16

    Seedlessness is an important agronomic trait for citrus, and male sterility (MS) is one main cause of seedless citrus fruit. However, the molecular mechanism of citrus seedlessness remained not well explored. An integrative strategy combining suppression subtractive hybridization (SSH) library with cDNA microarray was employed to study the underlying mechanism of seedlessness of a Ponkan mandarin seedless mutant (Citrus reticulata Blanco). Screening with custom microarray, a total of 279 differentially expressed clones were identified, and 133 unigenes (43 contigs and 90 singletons) were obtained after sequencing. Gene Ontology (GO) distribution based on biological process suggested that the majority of differential genes are involved in metabolic process and respond to stimulus and regulation of biology process; based on molecular function they function as DNA/RNA binding or have catalytic activity and oxidoreductase activity. A gene encoding male sterility-like protein was highly up-regulated in the seedless mutant compared with the wild type, while several transcription factors (TFs) such as AP2/EREBP, MYB, WRKY, NAC and C2C2-GATA zinc-finger domain TFs were down-regulated. Our research highlighted some candidate pathways that participated in the citrus male gametophyte development and could be beneficial for seedless citrus breeding in the future.

  14. Comparative transcript profiling of gene expression between seedless Ponkan mandarin and its seedy wild type during floral organ development by suppression subtractive hybridization and cDNA microarray

    PubMed Central

    2012-01-01

    Background Seedlessness is an important agronomic trait for citrus, and male sterility (MS) is one main cause of seedless citrus fruit. However, the molecular mechanism of citrus seedlessness remained not well explored. Results An integrative strategy combining suppression subtractive hybridization (SSH) library with cDNA microarray was employed to study the underlying mechanism of seedlessness of a Ponkan mandarin seedless mutant (Citrus reticulata Blanco). Screening with custom microarray, a total of 279 differentially expressed clones were identified, and 133 unigenes (43 contigs and 90 singletons) were obtained after sequencing. Gene Ontology (GO) distribution based on biological process suggested that the majority of differential genes are involved in metabolic process and respond to stimulus and regulation of biology process; based on molecular function they function as DNA/RNA binding or have catalytic activity and oxidoreductase activity. A gene encoding male sterility-like protein was highly up-regulated in the seedless mutant compared with the wild type, while several transcription factors (TFs) such as AP2/EREBP, MYB, WRKY, NAC and C2C2-GATA zinc-finger domain TFs were down-regulated. Conclusion Our research highlighted some candidate pathways that participated in the citrus male gametophyte development and could be beneficial for seedless citrus breeding in the future. PMID:22897898

  15. Proteomic analysis of berry-sizing effect of GA3 on seedless Vitis vinifera L.

    PubMed

    Wang, Zeng; Zhao, Fengxia; Zhao, Xiao; Ge, Hui; Chai, Lijuan; Chen, Shangwu; Perl, Avihai; Ma, Huiqin

    2012-01-01

    Gibberellin (GA) is widely used in the table grape and raisin industries to enlarge the berries of seedless varieties. However, the mechanism underlying its berry-sizing effect is poorly understood. In this study, clusters of Centennial Seedless (Vitis vinifera L.) were treated with 30 ppm GA3 on day 12 after flowering, and berries were sampled at development stages I, II and III for proteomic analysis. Among the 1479 proteins detected on 2-DE maps, 19, 70 and 69 spots in stages I, II and III, respectively, showed an at least twofold difference in volume between treatments and controls. Of these, 125 proteins were successfully identified and assigned to eight functional groups, chief among them are metabolism and energy, stress response, expression regulation and cytoskeleton proteins. Stress-response proteins were predominantly down-regulated in GA3-treated berries in stages I and II, and significantly up-regulated in stage III. Up-regulation of cytoskeleton, cell-wall modification and other important proteins was found in the two latter stages of berry development. Our proteomic results and subsequent validation revealed, for the first time, the role of redox homeostasis in GA3-induced berry enlargement and markedly remodeled cellular protein expression in treated berries.

  16. Accumulation of weathered pp'-DDE in xylem sap of grafted watermelon.

    PubMed

    Isleyen, Mehmet; Sevim, Pinar

    2012-04-01

    Movement of weathered p,p'-dichlorodiphenyldichloroethane (p,p'-DDE) from contaminated soil to the rhizosphere pore water to the xylem sap of grafted watermelon was studied under green house conditions. p,p'-DDE concentrations in pore water and xylem sap was compared in intact plants, homografted, and compatible heterografts of Cucurbita pepo spp. pepo and Citrullus lanatus plants. An average p,p'-DDE concentrations in pore water of contaminated soil ranged from 0.36 microg/L to 0.55 microg/L and there were no statistically significant among the cultivars. Conversely, the xylem sap p,p'-DDE concentration of heterografted watermelon having a zucchini rootstock and watermelon scion was 71 microg/L and it was greater than intact watermelon plants (0.49 microg/L) but less than that of intact plants of zucchini (141 microg/L). Homografting showed no effect on xylem sap p,p'-DDE concentrations of the identical cultivars. The bio-concentration factors (BCFs) which is an average p,p'-DDE concentration in xylem sap over average p,p'-DDE in pore water were 344, 325, 197, 1.28, and 0.89 for intact plant of zucchini, homografted zucchini, heterografted watermelon, homografted watermelon, and intact plant of watermelon, respectively. Xylem sap p,p'-DDE concentrations of the heterografted watermelon plants were clearly influenced by plant phylogeny and enhanced by the zucchini rootstock compared to intact watermelon plants.

  17. Molecular, genetic and transcriptional evidence for a role of VvAGL11 in stenospermocarpic seedlessness in grapevine

    PubMed Central

    2011-01-01

    Background Stenospermocarpy is a mechanism through which certain genotypes of Vitis vinifera L. such as Sultanina produce berries with seeds reduced in size. Stenospermocarpy has not yet been characterized at the molecular level. Results Genetic and physical maps were integrated with the public genomic sequence of Vitis vinifera L. to improve QTL analysis for seedlessness and berry size in experimental progeny derived from a cross of two seedless genotypes. Major QTLs co-positioning for both traits on chromosome 18 defined a 92-kb confidence interval. Functional information from model species including Vitis suggested that VvAGL11, included in this confidence interval, might be the main positional candidate gene responsible for seed and berry development. Characterization of VvAGL11 at the sequence level in the experimental progeny identified several SNPs and INDELs in both regulatory and coding regions. In association analyses performed over three seasons, these SNPs and INDELs explained up to 78% and 44% of the phenotypic variation in seed and berry weight, respectively. Moreover, genetic experiments indicated that the regulatory region has a larger effect on the phenotype than the coding region. Transcriptional analysis lent additional support to the putative role of VvAGL11's regulatory region, as its expression is abolished in seedless genotypes at key stages of seed development. These results transform VvAGL11 into a functional candidate gene for further analyses based on genetic transformation. For breeding purposes, intragenic markers were tested individually for marker assisted selection, and the best markers were those closest to the transcription start site. Conclusion We propose that VvAGL11 is the major functional candidate gene for seedlessness, and we provide experimental evidence suggesting that the seedless phenotype might be caused by variations in its promoter region. Current knowledge of the function of its orthologous genes, its expression

  18. Identification of gamma-irradiated papaya, melon and watermelon

    NASA Astrophysics Data System (ADS)

    Marín-Huachaca, Nélida S.; Mancini-Filho, Jorge; Delincée, Henry; Villavicencio, Anna Lúcia C. H.

    2004-09-01

    Ionizing radiation can be used to control spoilage microorganisms and to increase the shelf life of fresh fruits and vegetables in replacement for the treatment with chemical fumigants. In order to enforce labelling regulations, methods for detecting the irradiation treatment directly in the produce are required. Recently, a number of detection methods for irradiated food have been adopted by the Codex Comission. A rapid screening method for qualitative detection of irradiation is the DNA Comet Assay. The applicability of the DNA Comet Assay for distinguishing irradiated papaya, melon, and watermelon was evaluated. The samples were treated in a 60Co facility at dose levels of 0.0, 0.5, 0.75, and 1.0kGy. The irradiated samples showed typical DNA fragmentation whereas cells from non-irradiated ones appeared intact. In addition to the DNA Comet Assay also the half-embryo test was applied in melon and watermelon to detect the irradiation treatment.

  19. Impact of pretreatment on colour and texture of watermelon rind

    NASA Astrophysics Data System (ADS)

    Athmaselvi, K.; Alagusundaram, K.; Kavitha, C.; Arumuganathan, T.

    2012-07-01

    The effect of osmotic dehydration pretreatment on water loss, solid gain, colour and textural change was investigated. Watermelon rind 1 x 1 cm size was immersed in sucrose solution of 40, 50 and 60° Brix after pretreatment with microwave and conventional boiling in water for 1, 3, and 5 min, respectively. Water loss and solid gain increased with the time of cooking and sugar concentration. Microwave pretreated samples showed higher water loss and solid gain. Increase in the time of cooking decreased the brightness of all the samples. Microwave pretreated samples showed higher `b' values than conventionally pretreated ones. There was no significant difference (P≤0.05) in texture profile analysis parameters except for hardness. Hardness decreased with increase in time of cooking and sugar concentration. Second order regression model was developed for water loss and solid gain of microwave and conventional pretreated watermelon rind.

  20. Adsorption study of Ammonia Nitrogen by watermelon rind

    NASA Astrophysics Data System (ADS)

    Ibrahim, A.; Yusof, L.; Beddu, N. S.; Galasin, N.; Lee, P. Y.; Lee, R. N. S.; Zahrim, A. Y.

    2016-06-01

    The utilization of fruit waste for low-cost adsorbents as a replacement for costly conventional methods of removing ammonia nitrogen from wastewater has been reviewed. The adsorption studies were conducted as a function of contact time and adsorbent dosage and it were carried out on four different adsorbents; fresh watermelon rind and modified watermelon rind with sodium hydroxide (NaOH), potassium hydroxide (KOH) and sulphuric acid (H2SO4). Adsorbents were tested for characterization by using zeta potential test and all samples shows negative values thus makes it favourable for the adsorption process. The batch experimental result showed that adsorption process is rapid and equilibrium was established within 40 minutes of contact time. The ammonia nitrogen removal rate amounted in range of 96% to 99%, and the adsorption capacities were in range of 1.21 to 1.24 mg/g for all four different types of adsorbents used.

  1. Characterisation and functional properties of watermelon (Citrullus lanatus) seed proteins.

    PubMed

    Wani, Ali Abas; Sogi, Dalbir Singh; Singh, Preeti; Wani, Idrees Ahmed; Shivhare, Uma S

    2011-01-15

    People in developing countries depend largely on non-conventional protein sources to augment the availability of proteins in their diets. Watermelon seed meal is reported to contain an adequate amount of nutritional proteins that could be extracted for use as nutritional ingredients in food products. Osborne classification showed that globulin was the major protein (≥500 g kg (-1)) present in watermelon seed meal, followed by albumin and glutelin. Sodium dodecyl sulfate polyacrylamide gel electrophoresis indicated that the polypeptides had low molecular weights ranging from 35 to 47 kDa. Isoelectric focusing revealed that the isoelectric point of most proteins was in the acidic range 4-6. These proteins are rich in aspartic acid, glutamic acid and serine. An increase in pH (5-9) significantly (P < 0.05) decreased the denaturation enthalpy of these proteins. Among functional properties, albumin exhibited a much higher dispersibility index (810.3-869.6 g kg(-1)) than globulin (227.8-245.4 g kg(-1)), glutelin (182.1-187.7 g kg(-1)) and prolamin (162.3-177.7 g kg(-1)). Digestibility was in the ranges 760.6-910.0 and 765.5-888.5 g kg(-1) for Mateera and Sugar Baby watermelon protein fractions respectively, while surface hydrophobicity ranged from 126.4 to 173.2 and from 125.8 to 169.3 respectively. The foaming and emulsifying properties of albumin were better than those of the other proteins studied. The good nutritional and functional properties of watermelon seed meal proteins suggest their potential use in food formulations. Copyright © 2010 Society of Chemical Industry.

  2. Configuration of watermelon fruit quality in response to rootstock-mediated harvest maturity and postharvest storage.

    PubMed

    Kyriacou, Marios C; Soteriou, Georgios A; Rouphael, Youssef; Siomos, Anastasios S; Gerasopoulos, Dimitrios

    2016-05-01

    The configuration of watermelon fruit quality was analysed in a multi-factorial approach accounting for the effects of grafting, harvest maturity and postharvest storage. Diploid, seeded, hybrid cv. Pegasus, cultivated as scion on interspecific hybrid squash rootstock TZ148 and as non-grafted control, was stored at 25 °C following sequential harvests from the onset of ripening to over-maturity. Delayed rootstock-mediated climax in pulp lycopene and chroma was observed, while both were heightened by postharvest storage when harvest preceded full maturity. Pulp firmness was increased by 46.5% on TZ148, while postharvest decrease in firmness was non-significant. Non-grafted fruits attained their peak in pulp carbohydrate content earlier during ripening. Monosaccharide content declined and sucrose content increased both preharvest and postharvest; overall sugar content declined by 4.3% during storage. Pulp acidity decreased steadily with ripening but was moderately increased by grafting. Citrulline content increased by 12.5% on TZ148; moreover, it climaxed with ripening and declined with storage only in grafted fruit. Grafting enhances pulp texture and bioactive composition. Potential suppression of sugar content as a result of grafting is minimized at full commercial maturity. Brief postharvest ambient storage enhances pulp lycopene and chroma, especially in early-picked fruit, notwithstanding the depletion of monosaccharides and citrulline and a limited deterioration of texture. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  3. Watermelon consumption improves inflammation and antioxidant capacity in rats fed an atherogenic diet.

    PubMed

    Hong, Mee Young; Hartig, Nicole; Kaufman, Katy; Hooshmand, Shirin; Figueroa, Arturo; Kern, Mark

    2015-03-01

    Cardiovascular disease (CVD) is the leading cause of death in the United States. Watermelon, rich in antioxidants and other bioactive components, may be a viable method to improve CVD risk factors through reduced oxidative stress. The purpose of the study was to determine the effects of watermelon powder consumption on lipid profiles, antioxidant capacity, and inflammation in dextran sodium sulfate (DSS)-treated rats fed an atherogenic diet. We hypothesized that watermelon would increase antioxidant capacity and reduce blood lipids and inflammation through modulation of related gene expression. Forty male-weanling (21 days old) Sprague-Dawley rats were divided into 4 groups (10 per group, total N = 40) in a 2 diets (control or 0.33% watermelon) × 2 treatments (with or without DSS) factorial design using an atherogenic diet. Watermelon-fed groups exhibited significantly lower serum triglycerides, total cholesterol, and low-density lipoprotein cholesterol (P< .05). C-reactive protein levels were significantly lower in watermelon-fed rats than the control (P= .001). In addition, oxidative stress as measured by thiobarbituric acid reactive substances was significantly lower in watermelon groups (P= .001). Total antioxidant capacity, superoxide dismutase, and catalase activities were greater in watermelon groups (P< .05). Aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase were significantly lower in DSS-treated rats when watermelon was consumed (P< .05). Fatty acid synthase, 3-hydroxy-3methyl-glutaryl-CoA reductase, sterol regulatory element-binding protein 1, sterol regulatory element-binding protein 2, and cyclooxygenase-2 gene expression was significantly downregulated in the watermelon group without DSS (P< .05). These findings indicate that watermelon improves risk factors for CVD in rats through better lipid profiles, lower inflammation, and greater antioxidant capacity by altering gene expression for lipid

  4. 7 CFR 319.56-36 - Watermelon, squash, cucumber, and oriental melon from the Republic of Korea.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 5 2014-01-01 2014-01-01 false Watermelon, squash, cucumber, and oriental melon from... QUARANTINE NOTICES Fruits and Vegetables § 319.56-36 Watermelon, squash, cucumber, and oriental melon from the Republic of Korea. Watermelon (Citrullus lanatus), squash (Cucurbita maxima), cucumber...

  5. 7 CFR 319.56-36 - Watermelon, squash, cucumber, and oriental melon from the Republic of Korea.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 5 2011-01-01 2011-01-01 false Watermelon, squash, cucumber, and oriental melon from... QUARANTINE NOTICES Fruits and Vegetables § 319.56-36 Watermelon, squash, cucumber, and oriental melon from the Republic of Korea. Watermelon (Citrullus lanatus), squash (Cucurbita maxima), cucumber...

  6. 7 CFR 319.56-36 - Watermelon, squash, cucumber, and oriental melon from the Republic of Korea.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Watermelon, squash, cucumber, and oriental melon from... QUARANTINE NOTICES Fruits and Vegetables § 319.56-36 Watermelon, squash, cucumber, and oriental melon from the Republic of Korea. Watermelon (Citrullus lanatus), squash (Cucurbita maxima), cucumber...

  7. 7 CFR 319.56-36 - Watermelon, squash, cucumber, and oriental melon from the Republic of Korea.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 5 2013-01-01 2013-01-01 false Watermelon, squash, cucumber, and oriental melon from... QUARANTINE NOTICES Fruits and Vegetables § 319.56-36 Watermelon, squash, cucumber, and oriental melon from the Republic of Korea. Watermelon (Citrullus lanatus), squash (Cucurbita maxima), cucumber...

  8. 7 CFR 319.56-36 - Watermelon, squash, cucumber, and oriental melon from the Republic of Korea.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 5 2012-01-01 2012-01-01 false Watermelon, squash, cucumber, and oriental melon from... QUARANTINE NOTICES Fruits and Vegetables § 319.56-36 Watermelon, squash, cucumber, and oriental melon from the Republic of Korea. Watermelon (Citrullus lanatus), squash (Cucurbita maxima), cucumber...

  9. Development of Phytophthora fruit rot caused by Phytophthora capsici on resistant and susceptible watermelon fruit of different ages

    USDA-ARS?s Scientific Manuscript database

    Watermelon is an important crop grown in 44 states in the United States. Phytophthora fruit rot caused by Phytophthora capsici is a serious disease in the southeastern U.S., where over 50% of the watermelons are produced. The disease has resulted in severe losses to watermelon growers, especially in...

  10. The FonSIX6 gene acts as an avirulence effector in the Fusarium oxysporum f. sp. niveum - watermelon pathosystem

    USDA-ARS?s Scientific Manuscript database

    There are three generally accepted Fusarium oxysporum f. sp. niveum (Fon) physiological races (0, 1, and 2) that infect watermelon (Citrullus lanatus). Among them, race 1 is the most prevalent on watermelon throughout the world, while race 2 is highly aggressive to all commercial watermelon cultivar...

  11. Evolution of haploid selection in predominantly diploid organisms.

    PubMed

    Otto, Sarah P; Scott, Michael F; Immler, Simone

    2015-12-29

    Diploid organisms manipulate the extent to which their haploid gametes experience selection. Animals typically produce sperm with a diploid complement of most proteins and RNA, limiting selection on the haploid genotype. Plants, however, exhibit extensive expression in pollen, with actively transcribed haploid genomes. Here we analyze models that track the evolution of genes that modify the strength of haploid selection to predict when evolution intensifies and when it dampens the "selective arena" within which male gametes compete for fertilization. Considering deleterious mutations, evolution leads diploid mothers to strengthen selection among haploid sperm/pollen, because this reduces the mutation load inherited by their diploid offspring. If, however, selection acts in opposite directions in haploids and diploids ("ploidally antagonistic selection"), mothers evolve to reduce haploid selection to avoid selectively amplifying alleles harmful to their offspring. Consequently, with maternal control, selection in the haploid phase either is maximized or reaches an intermediate state, depending on the deleterious mutation rate relative to the extent of ploidally antagonistic selection. By contrast, evolution generally leads diploid fathers to mask mutations in their gametes to the maximum extent possible, whenever masking (e.g., through transcript sharing) increases the average fitness of a father's gametes. We discuss the implications of this maternal-paternal conflict over the extent of haploid selection and describe empirical studies needed to refine our understanding of haploid selection among seemingly diploid organisms.

  12. Determination of acoustic vibration in watermelon by finite element modeling

    NASA Astrophysics Data System (ADS)

    Nourain, Jamal; Ying, Yibin B.; Wang, Jianping; Rao, Xiuqin

    2004-11-01

    The analysis of the vibration responses of a fruit is suggested to measure firmness non-destructively. A wooden ball excited the fruits and the response signals were captured using an accelerometer sensor. The method has been well studied and understood on ellipsoidal shaped fruit (watermelon). In this work, using the finite element simulations, the applicability of the method on watermelon was investigated. The firmness index is dependent on the mass, density, and natural frequency of the lowest spherical modes (under free boundary conditions). This developed index extends the firmness estimation for fruits or vegetables from a spherical to an ellipsoidal shape. The mode of Finite element analysis (FEA) of watermelon was generated based on measured geometry, and it can be served as a theoretical reference for predicting the modal characteristics as a function of design parameters such as material, geometrical, and physical properties. It was found that there were four types of mode shapes. The 1st one was first-type longitudinal mode, the 2nd one was the second-type longitudinal mode, the 3rd one was breathing mode or pure compression mode, and the fourth was flexural or torsional mode shape. As suggested in many references, the First-type spherical vibration mode or oblate-Prolate for watermelon is the lowest bending modes, it's most likely related to fruit firmness. Comparisons of finite element and experimental modal parameters show that both results were agreed in mode shape as well as natural frequencies. In order to measure the vibration signal of the mode, excitation and sensors should be placed on the watermelon surface far away from the nodal lines. The excitation and the response sensors should be in accordance with vibration directions. The correlations between the natural frequency and firmness was 0.856, natural frequency and Young's modulus was 0.800, and the natural frequency and stiffness factor (SF) was 0.862. The stiffness factor (SF) is adequate

  13. Physiological effects of magnetic iron oxide nanoparticles towards watermelon.

    PubMed

    Li, Junli; Chang, Peter R; Huang, Jin; Wang, Yunqiang; Yuan, Hong; Ren, Hongxuan

    2013-08-01

    Nanoparticles (NPs) have been exploited in a diverse range of products in the past decade or so. However, the biosafety/environmental impact or legislation pertaining to this newly created, highly functional composites containing NPs (otherwise called nanomaterials) is generally lagging behind their technological innovation. To advance the agenda in this area, our current primary interest is focused on using crops as model systems as they have very close relationship with us. Thus, the objective of the present study was to evaluate the biological effects of magnetic iron oxide nanoparticles towards watermelon seedlings. We have systematically studied the physiological effects of Fe2O3 nanoparticles (nano-Fe2O3) on watermelon, and present the first evidence that a significant amount of Fe2O3 nanoparticles suspended in a liquid medium can be taken up by watermelon plants and translocated throughout the plant tissues. Changes in important physiological indicators, such as root activity, activity of catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD), chlorophyll and malondialdehyde (MDA) contents, ferric reductase activity, root apoplastic iron content were clearly presented. Different concentrations of nano-Fe2O3 all increased seed germination, seedling growth, and enhanced physiological function to some degree; and the positive effects increased quickly and then slowed with an increase in the treatment concentrations. Changes in CAT, SOD and POD activities due to nano-Fe2O3 were significantly larger than that of the control. The 20 mg/L treatment had the most obvious effect on the increase of root activity. Ferric reductase activity, root apoplastic iron content, and watermelon biomass were significantly affected by exposure to nano-Fe2O3. Results of statistical analysis showed that there were significant differences in all the above indexes between the treatment at optimal concentration and the control. This proved that the proper concentration of nano

  14. Transcriptional regulation of lycopene metabolism mediated by rootstock during the ripening of grafted watermelons.

    PubMed

    Kong, Qiusheng; Yuan, Jingxian; Gao, Lingyun; Liu, Peng; Cao, Lei; Huang, Yuan; Zhao, Liqiang; Lv, Huifang; Bie, Zhilong

    2017-01-01

    Rootstocks have comprehensive effects on lycopene accumulation in grafted watermelon fruits. However, little is known about lycopene metabolic regulation in grafted watermelon. To address this problem, parallel changes in lycopene contents and the expression of its metabolic genes were analyzed during the fruit ripening of nongrafted watermelon and watermelon grafted onto bottle gourd, pumpkin, and wild watermelon. Results showed that rootstocks mediated the transcriptional regulations of lycopene accumulation in different ways. Bottle gourd and wild watermelon promoted lycopene accumulation in grafted watermelon fruits by upregulating the biosynthetic genes phytoene synthase (PSY) and ζ-carotene desaturase (ZDS), and downregulating the catabolic genes β-carotene hydroxylase (CHYB), zeaxanthin epoxidase (ZEP), 9-cis-epoxycarotenoid dioxygenase (NCED), and carotenoid cleavage dioxygenase (CCD). However, pumpkin did not affect lycopene accumulation by upregulating both biosynthetic and catabolic genes. The rootstock-dependent characteristic of lycopene accumulation in grafted watermelon fruits provided an alternative model for investigating lycopene metabolic regulation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Can You Tell the Density of the Watermelon from This Photograph?

    ERIC Educational Resources Information Center

    Foong, See Kit; Lim, Chim Chai

    2010-01-01

    Based on a photograph, the density of a watermelon floating in a pail of water is estimated with different levels of simplification--with and without consideration of refraction and three-dimensional effects. The watermelon was approximated as a sphere. The results of the theoretical estimations were verified experimentally. (Contains 6 figures.)

  16. An improved assay for detection of Acidovorax avenae subsp. citrulli in watermelon and melon seed

    USDA-ARS?s Scientific Manuscript database

    Acidovorax avenae subsp. citrulli (Aac), the causal agent of a watermelon seedling blight and fruit blotch (WFB), has emerged as a serious seedborne pathogen of watermelon, melons, pumpkin, and citron. Although attempts have been made to develop a simple routine laboratory seed assay to detect the...

  17. Transcriptome Profiling of Watermelon Root in Response to Short-Term Osmotic Stress

    PubMed Central

    Yang, Yongchao; Mo, Yanling; Yang, Xiaozheng; Zhang, Haifei; Wang, Yongqi; Li, Hao; Wei, Chunhua; Zhang, Xian

    2016-01-01

    Osmotic stress adversely affects the growth, fruit quality and yield of watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai). Increasing the tolerance of watermelon to osmotic stress caused by factors such as high salt and water deficit is an effective way to improve crop survival in osmotic stress environments. Roots are important organs in water absorption and are involved in the initial response to osmosis stress; however, few studies have examined the underlying mechanism of tolerance to osmotic stress in watermelon roots. For better understanding of this mechanism, the inbred watermelon accession M08, which exhibits relatively high tolerance to water deficits, was treated with 20% polyethylene glycol (PEG) 6000. The root samples were harvested at 6 h after PEG treatment and untreated samples were used as controls. Transcriptome analyses were carried out by Illumina RNA sequencing. A total of 5246 differentially expressed genes were identified. Gene ontology enrichment and biochemical pathway analyses of these 5246 genes showed that short-term osmotic stress affected osmotic adjustment, signal transduction, hormone responses, cell division, cell cycle and ribosome, and M08 may repress root growth to adapt osmotic stress. The results of this study describe the watermelon root transcriptome under osmotic stress and propose new insight into watermelon root responses to osmotic stress at the transcriptome level. Accordingly, these results allow us to better understand the molecular mechanisms of watermelon in response to drought stress and will facilitate watermelon breeding projects to improve drought tolerance. PMID:27861528

  18. Can You Tell the Density of the Watermelon from This Photograph?

    ERIC Educational Resources Information Center

    Foong, See Kit; Lim, Chim Chai

    2010-01-01

    Based on a photograph, the density of a watermelon floating in a pail of water is estimated with different levels of simplification--with and without consideration of refraction and three-dimensional effects. The watermelon was approximated as a sphere. The results of the theoretical estimations were verified experimentally. (Contains 6 figures.)

  19. Is Grafting Useful for Managing Root-Knot Nematodes in Watermelon?

    USDA-ARS?s Scientific Manuscript database

    Five Citrullus lanatus var. citroides germplasm lines, four Lagenaria siceraria cultivars, one Cucurbita moschata x C. maxima hybrid, and one commercial wild watermelon (Citrullus lanatus spp.) cultivar were evaluated as rootstocks for watermelon in a field infested with the southern root-knot nemat...

  20. Evaluation of Actigard and Fungicides for Managing Phytophthora Fruit Rot of Watermelon, 2010

    USDA-ARS?s Scientific Manuscript database

    Phytophthora fruit rot caused by Phytophthora capsici is an emerging disease in most watermelon producing regions of Southeast U.S., and has been considered as a top research priority by the National Watermelon Association (NWA). Managing Phytophthora fruit rot can be difficult because of the l...

  1. Effect of actigard and other new fungicides on phytophthora fruit rot of watermelon

    USDA-ARS?s Scientific Manuscript database

    Fruit rot, caused by Phytophthora capsici is an emerging disease in most watermelon producing regions of Southeast U.S. Between 2003 and 2008, we observed many watermelon farms in Georgia, South Carolina, and North Carolina, where growers did not harvest the crop due to severe fruit rot. The Natio...

  2. A high resolution genetic map anchoring scaffolds of the sequenced watermelon genome

    USDA-ARS?s Scientific Manuscript database

    As part of our ongoing efforts to sequence and map the watermelon (Citrullus spp.) genome, we have constructed a high-density genetic linkage map. The map positioned 234 watermelon genome sequence scaffolds (an average size of 1.41 Mb) that cover about 330 Mb and account for 93.5% of the 353 Mb of ...

  3. Fungicide rotation schemes for managing Phytophthora fruit rot of watermelon across southeastern United States

    USDA-ARS?s Scientific Manuscript database

    Southeastern states produce about 50% of the watermelons in the United States (U.S.) where conditions are optimal for development of Phytophthora fruit rot prevail. Phytophthora fruit rot significantly limits watermelon production by causing serious yield losses to growers before and after harvest. ...

  4. Watermelon transplanted by chisel, strip-tillage, and bedding methods produce similar yield and quality

    USDA-ARS?s Scientific Manuscript database

    Watermelon plants grown in semi-arid, subtropical south Texas (Lat. 26° N) are subject to wind and high solar loads. In an effort to provide an environment that would reduce wind-related sand blasting, early transplant desiccation, and vine damage and reduced soil temperatures, watermelon seedlings...

  5. First Report Of Vine Decline Of Mature Watermelon Plants Caused By Olpidium Bornovanus

    USDA-ARS?s Scientific Manuscript database

    This is the first report of Olpidium bornovanus as a root pathogen of field-grown watermelon, and describes its association with a late season watermelon vine decline in the field. This report provides an overview of this fungus for growers, extension workers, crop consultants and research and regu...

  6. Identification and Utility of Markers Linked to the Zucchini Yellow Mosaic Virus Resistance Gene in Watermelon

    USDA-ARS?s Scientific Manuscript database

    Zucchini yellow mosaic virus (ZYMV) is one of the most economically important viruses affecting watermelon in the United States. The ZYMV-Florida strain (ZYMV-FL) is considered a major limitation to commercial watermelon production in the entire United States. Experiments with F2 and BC1 plants, d...

  7. Powdery mildew resistant cucurbit rootstocks confer tolerance to grafted susceptible watermelon scions

    USDA-ARS?s Scientific Manuscript database

    Cucurbit powdery mildew (PM) caused by Podosphaera xanthii can impact seedling growth and cause serious losses in greenhouse and open fields. We have developed watermelon and bottle gourd germplasm lines with high levels of resistance to PM. A PM susceptible watermelon cultivar Mickey Lee (ML) was g...

  8. Phylogenetic Relationships Among Cucurbit Species Used as Rootstocks for Grafting Watermelon

    USDA-ARS?s Scientific Manuscript database

    There is an increased interest in the United States in grafting watermelon on cucurbit rootstocks to control soilborne diseases. Several cucurbit species including Lagenaria siceraria, Cucurbita spp. and Benincasa hispida (wax gourds) have been used in Asia as rootstocks for watermelon. In our pre...

  9. Watermelon enhances arginine availability in an animal model of type-II diabetes

    USDA-ARS?s Scientific Manuscript database

    Watermelon fruit contain lycopene, a red pigment known for its ability to scavenge free hydroxyl radicals. L-Citrulline, an amino acid that acts as a vasodilator and is a precursor of L-arginine, is found in all cucurbits, but is most plentiful in watermelon. In a study with Zucker diabetic fatty ...

  10. MSW-28 a full flavor crisp watermelon line with high lycopene and medium brix

    USDA-ARS?s Scientific Manuscript database

    Conventional breeding techniques have increased the immediately-available sugar content in watermelon, up to 14%. This results in a sweet flavor but greatly limits the watermelon serving size for people concerned about dietary sugar intake. The Agricultural Research Service of the United States De...

  11. A diploid wheat TILLING resource for wheat functional genomics.

    PubMed

    Rawat, Nidhi; Sehgal, Sunish K; Joshi, Anupama; Rothe, Nolan; Wilson, Duane L; McGraw, Nathan; Vadlani, Praveen V; Li, Wanlong; Gill, Bikram S

    2012-11-07

    Triticum monococcum L., an A genome diploid einkorn wheat, was the first domesticated crop. As a diploid, it is attractive genetic model for the study of gene structure and function of wheat-specific traits. Diploid wheat is currently not amenable to reverse genetics approaches such as insertion mutagenesis and post-transcriptional gene silencing strategies. However, TILLING offers a powerful functional genetics approach for wheat gene analysis. We developed a TILLING population of 1,532 M2 families using EMS as a mutagen. A total of 67 mutants were obtained for the four genes studied. Waxy gene mutation frequencies are known to be 1/17.6 - 34.4 kb DNA in polyploid wheat TILLING populations. The T. monococcum diploid wheat TILLING population had a mutation frequency of 1/90 kb for the same gene. Lignin biosynthesis pathway genes- COMT1, HCT2, and 4CL1 had mutation frequencies of 1/86 kb, 1/92 kb and 1/100 kb, respectively. The overall mutation frequency of the diploid wheat TILLING population was 1/92 kb. The mutation frequency of a diploid wheat TILLING population was found to be higher than that reported for other diploid grasses. The rate, however, is lower than tetraploid and hexaploid wheat TILLING populations because of the higher tolerance of polyploids to mutations. Unlike polyploid wheat, most mutants in diploid wheat have a phenotype amenable to forward and reverse genetic analysis and establish diploid wheat as an attractive model to study gene function in wheat. We estimate that a TILLING population of 5, 520 will be needed to get a non-sense mutation for every wheat gene of interest with 95% probability.

  12. A diploid wheat TILLING resource for wheat functional genomics

    PubMed Central

    2012-01-01

    Background Triticum monococcum L., an A genome diploid einkorn wheat, was the first domesticated crop. As a diploid, it is attractive genetic model for the study of gene structure and function of wheat-specific traits. Diploid wheat is currently not amenable to reverse genetics approaches such as insertion mutagenesis and post-transcriptional gene silencing strategies. However, TILLING offers a powerful functional genetics approach for wheat gene analysis. Results We developed a TILLING population of 1,532 M2 families using EMS as a mutagen. A total of 67 mutants were obtained for the four genes studied. Waxy gene mutation frequencies are known to be 1/17.6 - 34.4 kb DNA in polyploid wheat TILLING populations. The T. monococcum diploid wheat TILLING population had a mutation frequency of 1/90 kb for the same gene. Lignin biosynthesis pathway genes- COMT1, HCT2, and 4CL1 had mutation frequencies of 1/86 kb, 1/92 kb and 1/100 kb, respectively. The overall mutation frequency of the diploid wheat TILLING population was 1/92 kb. Conclusion The mutation frequency of a diploid wheat TILLING population was found to be higher than that reported for other diploid grasses. The rate, however, is lower than tetraploid and hexaploid wheat TILLING populations because of the higher tolerance of polyploids to mutations. Unlike polyploid wheat, most mutants in diploid wheat have a phenotype amenable to forward and reverse genetic analysis and establish diploid wheat as an attractive model to study gene function in wheat. We estimate that a TILLING population of 5, 520 will be needed to get a non-sense mutation for every wheat gene of interest with 95% probability. PMID:23134614

  13. Developmental, transcriptome, and genetic alterations associated with parthenocarpy in the grapevine seedless somatic variant Corinto bianco.

    PubMed

    Royo, Carolina; Carbonell-Bejerano, Pablo; Torres-Pérez, Rafael; Nebish, Anna; Martínez, Óscar; Rey, Manuel; Aroutiounian, Rouben; Ibáñez, Javier; Martínez-Zapater, José M

    2016-01-01

    Seedlessness is a relevant trait in grapevine cultivars intended for fresh consumption or raisin production. Previous DNA marker analysis indicated that Corinto bianco (CB) is a parthenocarpic somatic variant of the seeded cultivar Pedro Ximenes (PX). This study compared both variant lines to determine the basis of this parthenocarpic phenotype. At maturity, CB seedless berries were 6-fold smaller than PX berries. The macrogametophyte was absent from CB ovules, and CB was also pollen sterile. Occasionally, one seed developed in 1.6% of CB berries. Microsatellite genotyping and flow cytometry analyses of seedlings generated from these seeds showed that most CB viable seeds were formed by fertilization of unreduced gametes generated by meiotic diplospory, a process that has not been described previously in grapevine. Microarray and RNA-sequencing analyses identified 1958 genes that were differentially expressed between CB and PX developing flowers. Genes downregulated in CB were enriched in gametophyte-preferentially expressed transcripts, indicating the absence of regular post-meiotic germline development in CB. RNA-sequencing was also used for genetic variant calling and 14 single-nucleotide polymorphisms distinguishing the CB and PX variant lines were detected. Among these, CB-specific polymorphisms were considered as candidate parthenocarpy-responsible mutations, including a putative deleterious substitution in a HAL2-like protein. Collectively, these results revealed that the absence of a mature macrogametophyte, probably due to meiosis arrest, coupled with a process of fertilization-independent fruit growth, caused parthenocarpy in CB. This study provides a number of grapevine parthenocarpy-responsible candidate genes and shows how genomic approaches can shed light on the genetic origin of woody crop somatic variants. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions

  14. Cavitation Resistance in Seedless Vascular Plants: The Structure and Function of Interconduit Pit Membranes.

    PubMed

    Brodersen, Craig; Jansen, Steven; Choat, Brendan; Rico, Christopher; Pittermann, Jarmila

    2014-06-01

    Plant water transport occurs through interconnected xylem conduits that are separated by partially digested regions in the cell wall known as pit membranes. These structures have a dual function. Their porous construction facilitates water movement between conduits while limiting the spread of air that may enter the conduits and render them dysfunctional during a drought. Pit membranes have been well studied in woody plants, but very little is known about their function in more ancient lineages such as seedless vascular plants. Here, we examine the relationships between conduit air seeding, pit hydraulic resistance, and pit anatomy in 10 species of ferns (pteridophytes) and two lycophytes. Air seeding pressures ranged from 0.8 ± 0.15 MPa (mean ± sd) in the hydric fern Athyrium filix-femina to 4.9 ± 0.94 MPa in Psilotum nudum, an epiphytic species. Notably, a positive correlation was found between conduit pit area and vulnerability to air seeding, suggesting that the rare-pit hypothesis explains air seeding in early-diverging lineages much as it does in many angiosperms. Pit area resistance was variable but averaged 54.6 MPa s m(-1) across all surveyed pteridophytes. End walls contributed 52% to the overall transport resistance, similar to the 56% in angiosperm vessels and 64% in conifer tracheids. Taken together, our data imply that, irrespective of phylogenetic placement, selection acted on transport efficiency in seedless vascular plants and woody plants in equal measure by compensating for shorter conduits in tracheid-bearing plants with more permeable pit membranes.

  15. Origin of Cryptococcus neoformans var. neoformans Diploid Strains

    PubMed Central

    Cogliati, Massimo; Esposto, Maria C.; Clarke, David L.; Wickes, Brian L.; Viviani, Maria A.

    2001-01-01

    The basidiomycetous yeast Cryptococcus neoformans is an important human fungal pathogen. Two varieties, C. neoformans var. neoformans and C. neoformans var. gattii, have been identified. Both are heterothallic with two mating types, MATa and MATα. Some rare isolates are self-fertile and are considered occasional diploid or aneuploid strains. In the present study, 133 isolates, mostly from Italian patients, were investigated to detect the presence of diploid strains in the Igiene Università Milano culture collection. All of the diploid isolates were further investigated by different methods to elucidate their origins. Forty-nine diploid strains were identified by flow cytometry. PCR fingerprinting using the (GACA)4 primer showed that the diploid state was associated with two specific genotypes identified as VN3 and VN4. Determination of mating type on V8 juice medium confirmed that the majority of the strains were sterile. PCR and dot blotting using the two pheromone genes (MFa and MFα) as probes identified 36 of the 49 diploid isolates as MATa/α. The results of pheromone gene sequencing showed that two allelic MFα genes exist and are distinct for serotypes A and D. In contrast, the MFa gene sequence was conserved in both serotype alleles. Amplification of serotype-specific STE20 alleles demonstrated that the diploid strains contained one mating locus inherited from a serotype A parent and one inherited from a serotype D parent. The present results suggest that diploid isolates may be common among the C. neoformans population and that in Italy and other European countries serotype A and D populations are not genetically isolated but are able to recombine by sexual reproduction. PMID:11682503

  16. The Mediterranean: the cradle of Anthoxanthum (Poaceae) diploid diversity.

    PubMed

    Chumová, Zuzana; Záveská, Eliška; Mandáková, Terezie; Krak, Karol; Trávnícek, Pavel

    2017-08-01

    Knowledge of diploid phylogeny and ecogeography provide a foundation for understanding plant evolutionary history, diversification patterns and taxonomy. The genus Anthoxanthum (vernal grasses, Poaceae) represents a taxonomically intricate polyploid complex with large phenotypic variation and poorly resolved evolutionary relationships. The aims of the study were to reveal: (1) evolutionary lineages of the diploid taxa and their genetic differentiation; (2) the past distribution of the rediscovered 'Mediterranean diploid'; and (3) possible migration routes of diploids in the Mediterranean. A combined approach involving sequencing of two plastid regions ( trnL-trnF and rpl32-trnL ), nrDNA ITS, rDNA FISH analyses, climatic niche characterization and spatio-temporal modelling was used. Among the examined diploid species, only two well-differentiated evolutionary lineages were recognized: Anthoxanthum gracile and A. alpinum . The other taxa - A. aristatum, A. ovatum, A. maderense and the 'Mediterranean diploid' - form a rather intermixed group based on the examined molecular data. In situ rDNA localization enabled identification of the ancestral Anthoxanthum karyotype, shared by A. gracile and two taxa from the crown group. For the studied taxa, ancestral location probabilities for six discrete geographical regions in the Mediterranean were proposed and likely scenarios of gradual expansion from them were suggested. Modelling past and present distributions shows that the 'Mediterranean diploid' has already been occurring in the same localities for 120 000 years. Highly congruent results were obtained and dated the origin and first diversification of Anthoxanthum to the Miocene. The later divergence probably took place in the Pleistocene and started polyploid evolution within the genus. The most recent diversification event is still occurring, and incomplete lineage sorting prevents full diversification of taxa at the molecular level, despite clear separation based on

  17. Watermelon juice: a promising feedstock supplement, diluent, and nitrogen supplement for ethanol biofuel production

    PubMed Central

    Fish, Wayne W; Bruton, Benny D; Russo, Vincent M

    2009-01-01

    Background Two economic factors make watermelon worthy of consideration as a feedstock for ethanol biofuel production. First, about 20% of each annual watermelon crop is left in the field because of surface blemishes or because they are misshapen; currently these are lost to growers as a source of revenue. Second, the neutraceutical value of lycopene and L-citrulline obtained from watermelon is at a threshold whereby watermelon could serve as starting material to extract and manufacture these products. Processing of watermelons to produce lycopene and L-citrulline, yields a waste stream of watermelon juice at the rate of over 500 L/t of watermelons. Since watermelon juice contains 7 to 10% (w/v) directly fermentable sugars and 15 to 35 μmol/ml of free amino acids, its potential as feedstock, diluent, and nitrogen supplement was investigated in fermentations to produce bioethanol. Results Complete watermelon juice and that which did not contain the chromoplasts (lycopene), but did contain free amino acids, were readily fermentable as the sole feedstock or as diluent, feedstock supplement, and nitrogen supplement to granulated sugar or molasses. A minimum level of ~400 mg N/L (~15 μmol/ml amino nitrogen) in watermelon juice was required to achieve maximal fermentation rates when it was employed as the sole nitrogen source for the fermentation. Fermentation at pH 5 produced the highest rate of fermentation for the yeast system that was employed. Utilizing watermelon juice as diluent, supplemental feedstock, and nitrogen source for fermentation of processed sugar or molasses allowed complete fermentation of up to 25% (w/v) sugar concentration at pH 3 (0.41 to 0.46 g ethanol per g sugar) or up to 35% (w/v) sugar concentration at pH 5 with a conversion to 0.36 to 0.41 g ethanol per g sugar. Conclusion Although watermelon juice would have to be concentrated 2.5- to 3-fold to serve as the sole feedstock for ethanol biofuel production, the results of this investigation

  18. Niche differentiation between diploid and hexaploid Aster amellus.

    PubMed

    Raabová, Jana; Fischer, Markus; Münzbergová, Zuzana

    2008-12-01

    The maintenance of separated diploid and polyploid populations within a contact zone is possible due to both prezygotic and postzygotic isolation mechanisms. Niche differentiation between two cytotypes may be an important prezygotic isolating mechanism and can be studied using reciprocal transplant experiments. We investigated niche differentiation between diploid and hexaploid Aster amellus in their contact zone in the Czech Republic. Diploid populations are confined to habitats with low productivity, whereas hexaploid populations occur in habitats with both low and high productivity. Thus, we chose three diploid populations and six hexaploid populations, three in each of the two different habitat types. We analyzed habitat characteristics and carried out reciprocal transplant experiments in the field using both seeds and adult plants. Sites of diploid and hexaploid populations differed significantly in vegetation and soil properties. The mean number of juveniles was higher at sites of home ploidy level than at sites of foreign ploidy level, suggesting niche differentiation between the two cytotypes. On the other hand, transplanted adult plants survived at all sites and juvenile plants were able to establish at some sites of the foreign cytotype. Furthermore, the mean number of juveniles, survival, and flowering percentages were higher at home sites than at foreign sites, indicating local adaptation. We conclude that niche differentiation between the two cytotypes and local adaptation within each cytotype may contribute to the maintenance of diploid and hexaploid populations of A. amellus in their contact zone. Moreover, further factors, such as differences in flowering phenology and exclusion of minority cytotypes, should also be considered.

  19. Root Exudates from Grafted-Root Watermelon Showed a Certain Contribution in Inhibiting Fusarium oxysporum f. sp. niveum

    PubMed Central

    Wang, Dongsheng; Mao, Jiugeng; Huang, Qiwei; Guo, Shiwei; Shen, Qirong

    2013-01-01

    Grafting watermelon onto bottle gourd rootstock is commonly used method to generate resistance to Fusarium oxysporum f. sp. niveum (FON), but knowledge of the effect of the root exudates of grafted watermelon on this soil-borne pathogen in rhizosphere remains limited. To investigate the root exudate profiles of the own-root bottle gourd, grafted-root watermelon and own-root watermelon, recirculating hydroponic culture system was developed to continuously trap these root exudates. Both conidial germination and growth of FON were significantly decreased in the presence of root exudates from the grafted-root watermelon compared with the own-root watermelon. HPLC analysis revealed that the composition of the root exudates released by the grafted-root watermelon differed not only from the own-root watermelon but also from the bottle gourd rootstock plants. We identified salicylic acid in all 3 root exudates, chlorogenic acid and caffeic acid in root exudates from own-root bottle gourd and grafted-root watermelon but not own-root watermelon, and abundant cinnamic acid only in own-root watermelon root exudates. The chlorogenic and caffeic acid were candidates for potentiating the enhanced resistance of the grafted watermelon to FON, therefore we tested the effects of the two compounds on the conidial germination and growth of FON. Both phenolic acids inhibited FON conidial germination and growth in a dose-dependent manner, and FON was much more susceptible to chlorogenic acid than to caffeic acid. In conclusion, the key factor in attaining the resistance to Fusarium wilt is grafting on the non-host root stock, however, the root exudates profile also showed some contribution in inhibiting FON. These results will help to better clarify the disease resistance mechanisms of grafted-root watermelon based on plant-microbe communication and will guide the improvement of strategies against Fusarium-mediated wilt of watermelon plants. PMID:23700421

  20. Root exudates from grafted-root watermelon showed a certain contribution in inhibiting Fusarium oxysporum f. sp. niveum.

    PubMed

    Ling, Ning; Zhang, Wenwen; Wang, Dongsheng; Mao, Jiugeng; Huang, Qiwei; Guo, Shiwei; Shen, Qirong

    2013-01-01

    Grafting watermelon onto bottle gourd rootstock is commonly used method to generate resistance to Fusarium oxysporum f. sp. niveum (FON), but knowledge of the effect of the root exudates of grafted watermelon on this soil-borne pathogen in rhizosphere remains limited. To investigate the root exudate profiles of the own-root bottle gourd, grafted-root watermelon and own-root watermelon, recirculating hydroponic culture system was developed to continuously trap these root exudates. Both conidial germination and growth of FON were significantly decreased in the presence of root exudates from the grafted-root watermelon compared with the own-root watermelon. HPLC analysis revealed that the composition of the root exudates released by the grafted-root watermelon differed not only from the own-root watermelon but also from the bottle gourd rootstock plants. We identified salicylic acid in all 3 root exudates, chlorogenic acid and caffeic acid in root exudates from own-root bottle gourd and grafted-root watermelon but not own-root watermelon, and abundant cinnamic acid only in own-root watermelon root exudates. The chlorogenic and caffeic acid were candidates for potentiating the enhanced resistance of the grafted watermelon to FON, therefore we tested the effects of the two compounds on the conidial germination and growth of FON. Both phenolic acids inhibited FON conidial germination and growth in a dose-dependent manner, and FON was much more susceptible to chlorogenic acid than to caffeic acid. In conclusion, the key factor in attaining the resistance to Fusarium wilt is grafting on the non-host root stock, however, the root exudates profile also showed some contribution in inhibiting FON. These results will help to better clarify the disease resistance mechanisms of grafted-root watermelon based on plant-microbe communication and will guide the improvement of strategies against Fusarium-mediated wilt of watermelon plants.

  1. Sucrose accumulation in watermelon fruits: genetic variation and biochemical analysis.

    PubMed

    Yativ, Merav; Harary, Idan; Wolf, Shmuel

    2010-05-15

    Sugar accumulation, the key process determining fruit quality, is controlled by both the translocation of sugars and their metabolism in developing fruits. Sugar composition in watermelon, as in all cucurbit fruits, includes sucrose, fructose and glucose. The proportions of these three sugars are determined primarily by three enzyme families: invertases, sucrose synthases (SuSys) and sucrose phosphate synthases (SPSs). The goal of the present research was to explore the process of sugar metabolism in watermelon fruits. Crosses between the domestic watermelon (Citrullus lanatus) and three wild species provided a wide germplasm to explore genetic variability in sugar composition and metabolism. This survey demonstrated great genetic variability in sugar content and in the proportions of sucrose, glucose and fructose in mature fruits. Genotypes accumulating high and low percentage of sucrose provided an experimental system to study sugar metabolism in developing fruits. Insoluble invertase activity was high and constant throughout fruit development in control lines and in genotypes accumulating low levels of sucrose, while in genotypes accumulating high levels of sucrose, activity declined sharply 4 weeks after pollination. Soluble acid invertase activity was significantly lower in genotypes accumulating high levels of sucrose than in low-sucrose-accumulating genotypes. Conversely, activities of SuSy and SPS were higher in the high-sucrose-accumulating genotypes. The present results establish that, within the genus Citrullus, there are genotypes that accumulate a high percentage of sucrose in the fruit, while others accumulate high percentages of glucose and fructose. The significant negative correlation between insoluble invertase activity and fruit sucrose level suggests that sucrose accumulation is affected by both phloem unloading and sugar metabolism. (c) 2009 Elsevier GmbH. All rights reserved.

  2. The canonical equation of adaptive dynamics for Mendelian diploids and haplo-diploids.

    PubMed

    Metz, Johan A J; de Kovel, Carolien G F

    2013-12-06

    One of the powerful tools of adaptive dynamics is its so-called canonical equation (CE), a differential equation describing how the prevailing trait vector changes over evolutionary time. The derivation of the CE is based on two simplifying assumptions, separation of population dynamical and mutational time scales and small mutational steps. (It may appear that these two conditions rarely go together. However, for small step sizes the time-scale separation need not be very strict.) The CE was derived in 1996, with mathematical rigour being added in 2003. Both papers consider only well-mixed clonal populations with the simplest possible life histories. In 2008, the CE's reach was heuristically extended to locally well-mixed populations with general life histories. We, again heuristically, extend it further to Mendelian diploids and haplo-diploids. Away from strict time-scale separation the CE does an even better approximation job in the Mendelian than in the clonal case owing to gene substitutions occurring effectively in parallel, which obviates slowing down by clonal interference.

  3. The canonical equation of adaptive dynamics for Mendelian diploids and haplo-diploids

    PubMed Central

    Metz, Johan A. J.; de Kovel, Carolien G. F.

    2013-01-01

    One of the powerful tools of adaptive dynamics is its so-called canonical equation (CE), a differential equation describing how the prevailing trait vector changes over evolutionary time. The derivation of the CE is based on two simplifying assumptions, separation of population dynamical and mutational time scales and small mutational steps. (It may appear that these two conditions rarely go together. However, for small step sizes the time-scale separation need not be very strict.) The CE was derived in 1996, with mathematical rigour being added in 2003. Both papers consider only well-mixed clonal populations with the simplest possible life histories. In 2008, the CE's reach was heuristically extended to locally well-mixed populations with general life histories. We, again heuristically, extend it further to Mendelian diploids and haplo-diploids. Away from strict time-scale separation the CE does an even better approximation job in the Mendelian than in the clonal case owing to gene substitutions occurring effectively in parallel, which obviates slowing down by clonal interference. PMID:24516713

  4. Measurement of internal quality of watermelon by Vis/NIR diffuse transmittance technique

    NASA Astrophysics Data System (ADS)

    Tian, Haiqing; Xu, Huirong; Ying, Yibin; Lu, Huishan; Yu, Haiyan

    2006-10-01

    Watermelon is a popular fruit in the world. Soluble solids content (SSC) is major characteristic used for assessing watermelon internal quality. This study was about a method for nondestructive internal quality detection of watermelons by means of visible/Near Infrared (Vis/NIR) diffuse transmittance technique. Vis/NIR transmittance spectra of intact watermelons were acquired using a low-cost commercially available spectrometer when the watermelon was in motion (1.4m/s) and in static state. Spectra data were analyzed by partial least squares (PLS) method. The influences of different data preprocessing and spectra treatments were also investigated. Performance of different models was assessed in terms of root mean square errors of calibration (RMSEC), root mean square errors of prediction (RMSEP) and correlation coefficient (r) between the predicted and measured parameter values. Results showed that spectra data preprocessing influenced the performance of the calibration models and the PLS method can provide good results. The nondestructive Vis/NIR measurements provided good estimates of SSC index of watermelon both in motion and in static state, and the predicted values were highly correlated with destructively measured values. The results indicated the feasibility of Vis/NIR diffuse transmittance spectral analysis for predicting watermelon internal quality in a nondestructive way.

  5. Evaluation of Appropriate Reference Genes for Gene Expression Normalization during Watermelon Fruit Development

    PubMed Central

    Kong, Qiusheng; Yuan, Jingxian; Gao, Lingyun; Zhao, Liqiang; Cheng, Fei; Huang, Yuan; Bie, Zhilong

    2015-01-01

    Gene expression analysis in watermelon (Citrullus lanatus) fruit has drawn considerable attention with the availability of genome sequences to understand the regulatory mechanism of fruit development and to improve its quality. Real-time quantitative reverse-transcription PCR (qRT-PCR) is a routine technique for gene expression analysis. However, appropriate reference genes for transcript normalization in watermelon fruits have not been well characterized. The aim of this study was to evaluate the appropriateness of 12 genes for their potential use as reference genes in watermelon fruits. Expression variations of these genes were measured in 48 samples obtained from 12 successive developmental stages of parthenocarpic and fertilized fruits of two watermelon genotypes by using qRT-PCR analysis. Considering the effects of genotype, fruit setting method, and developmental stage, geNorm determined clathrin adaptor complex subunit (ClCAC), β-actin (ClACT), and alpha tubulin 5 (ClTUA5) as the multiple reference genes in watermelon fruit. Furthermore, ClCAC alone or together with SAND family protein (ClSAND) was ranked as the single or two best reference genes by NormFinder. By using the top-ranked reference genes to normalize the transcript abundance of phytoene synthase (ClPSY1), a good correlation between lycopene accumulation and ClPSY1 expression pattern was observed in ripening watermelon fruit. These validated reference genes will facilitate the accurate measurement of gene expression in the studies on watermelon fruit biology. PMID:26110539

  6. Evaluation of Appropriate Reference Genes for Gene Expression Normalization during Watermelon Fruit Development.

    PubMed

    Kong, Qiusheng; Yuan, Jingxian; Gao, Lingyun; Zhao, Liqiang; Cheng, Fei; Huang, Yuan; Bie, Zhilong

    2015-01-01

    Gene expression analysis in watermelon (Citrullus lanatus) fruit has drawn considerable attention with the availability of genome sequences to understand the regulatory mechanism of fruit development and to improve its quality. Real-time quantitative reverse-transcription PCR (qRT-PCR) is a routine technique for gene expression analysis. However, appropriate reference genes for transcript normalization in watermelon fruits have not been well characterized. The aim of this study was to evaluate the appropriateness of 12 genes for their potential use as reference genes in watermelon fruits. Expression variations of these genes were measured in 48 samples obtained from 12 successive developmental stages of parthenocarpic and fertilized fruits of two watermelon genotypes by using qRT-PCR analysis. Considering the effects of genotype, fruit setting method, and developmental stage, geNorm determined clathrin adaptor complex subunit (ClCAC), β-actin (ClACT), and alpha tubulin 5 (ClTUA5) as the multiple reference genes in watermelon fruit. Furthermore, ClCAC alone or together with SAND family protein (ClSAND) was ranked as the single or two best reference genes by NormFinder. By using the top-ranked reference genes to normalize the transcript abundance of phytoene synthase (ClPSY1), a good correlation between lycopene accumulation and ClPSY1 expression pattern was observed in ripening watermelon fruit. These validated reference genes will facilitate the accurate measurement of gene expression in the studies on watermelon fruit biology.

  7. [Effects of straw mulching on soil moisture and watermelon yield in dryland].

    PubMed

    Sun, Hong-Xia; Wang, Wei; Zhang, Peng; Wang, Zhi-Wei; Jia, Zhi-Kuan; Yang, Bao-Ping; Han, Qing-Fang

    2014-07-01

    To explore the effects of straw mulching on soil moisture and yield of watermelon, corn straw was used as mulching materials, and three straw mulch treatments were performed, i. e., whole mulch (WM), rows mulch (SM) and root domain mulch (RM), and non-mulching as control. The results indicated that WM and RM treatments increased significantly soil water storage in 0-120 cm of soil layer under root domain and rows compared with the control during watermelon growth period, and soil water storage of RM was higher than that of SM after growing tendril. Effects of all straw mulch treatments on soil moisture were most obvious from watermelon post-growing tendril to pre-swelling and maturity. With the growth and development of watermelon, the three straw mulch treatments improved soil moisture around root domain, resulting in increased watermelon yields. Compared with the CK, the WM, SM and RM treatments significantly improved the yield and the water use efficiency of watermelon by 24.8%, 11.5% and 15.1%, and 42.7%, 24.3% and 29.4%. The WM with 13500 kg x hm(-2) straw was recommended for watermelon production in arid areas due to its favorable effect on soil storage moisture, yield and water use efficiency.

  8. Comparative Transcriptome Analysis of Cultivated and Wild Watermelon during Fruit Development

    PubMed Central

    Guo, Shaogui; Sun, Honghe; Zhang, Haiying; Liu, Jingan; Ren, Yi; Gong, Guoyi; Jiao, Chen; Zheng, Yi; Yang, Wencai; Fei, Zhangjun; Xu, Yong

    2015-01-01

    Watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] is an important vegetable crop world-wide. Watermelon fruit quality is a complex trait determined by various factors such as sugar content, flesh color and flesh texture. Fruit quality and developmental process of cultivated and wild watermelon are highly different. To systematically understand the molecular basis of these differences, we compared transcriptome profiles of fruit tissues of cultivated watermelon 97103 and wild watermelon PI296341-FR. We identified 2,452, 826 and 322 differentially expressed genes in cultivated flesh, cultivated mesocarp and wild flesh, respectively, during fruit development. Gene ontology enrichment analysis of these genes indicated that biological processes and metabolic pathways related to fruit quality such as sweetness and flavor were significantly changed only in the flesh of 97103 during fruit development, while those related to abiotic stress response were changed mainly in the flesh of PI296341-FR. Our comparative transcriptome profiling analysis identified critical genes potentially involved in controlling fruit quality traits including α-galactosidase, invertase, UDP-galactose/glucose pyrophosphorylase and sugar transporter genes involved in the determination of fruit sugar content, phytoene synthase, β-carotene hydroxylase, 9-cis-epoxycarotenoid dioxygenase and carotenoid cleavage dioxygenase genes involved in carotenoid metabolism, and 4-coumarate:coenzyme A ligase, cellulose synthase, pectinesterase, pectinesterase inhibitor, polygalacturonase inhibitor and α-mannosidase genes involved in the regulation of flesh texture. In addition, we found that genes in the ethylene biosynthesis and signaling pathway including ACC oxidase, ethylene receptor and ethylene responsive factor showed highly ripening-associated expression patterns, indicating a possible role of ethylene in fruit development and ripening of watermelon, a non-climacteric fruit. Our analysis provides

  9. Acceptability of minimally processed and irradiated pineapple and watermelon among Brazilian consumers

    NASA Astrophysics Data System (ADS)

    Martins, Cecília Geraldes; Aragon-Alegro, Lina Casale; Behrens, Jorge Herman; Oliveira Souza, Kátia Leani; Martins Vizeu, Dirceu; Hutzler, Beatriz Weltman; Teresa Destro, Maria; Landgraf, Mariza

    2008-06-01

    This study aimed at evaluating the acceptance of MP watermelon and pineapple exposed to 1.0 and 2.5 kGy compared to non-irradiated samples. No significant differences were observed in liking between irradiated and non-irradiated samples, and also between doses of 1.0 and 2.5 kGy. Significant differences in sourness (pineapple) or sweetness (watermelon) and between intention of purchase of irradiated and non-irradiated fruits were not observed as well. Results showed that MP watermelon and pineapple could be irradiated with doses up to 2.5 kGy without significant changes in acceptability.

  10. Silencing of chaperonin 21, that was differentially expressed in inflorescence of seedless and seeded grapes, promoted seed abortion in tobacco and tomato fruits.

    PubMed

    Hanania, Uri; Velcheva, Margarita; Or, Etti; Flaishman, Moshe; Sahar, Nachman; Perl, Avihai

    2007-08-01

    Vitis vinifera L. cv. 'Thompson Seedless' presents a type of stenospermocarpy in grape where fertilization occurs but seeds abort and fail to develop. To unravel the molecular basis for stenospermocarpy in grapes, subtractive hybridization was carried out in order to isolate differentially regulated genes that participate in the seedlessness machinery. Two 'Thompson' lines, a seeded and a seedless, were screened during different flower developmental stages. One of the genes, that was differentially expressed between the seeded and seedless lines, was the chloroplast chaperonin 21 (ch-Cpn21). ch-Cpn21 is a 21-kDa co-chaperonin polypeptide formed by two GroES-like domains fused together in tandem. Silencing of ch-Cpn21 in Nicotiana benthamiana plants resulted in leaf stunting, chlorosis, as well as ovary necrogenesis leading to seed abortion. Moreover, organ-specific silencing of ch-Cpn21 only in Lycopersicum esculentum fruits resulted in the development of seedless tomatoes. These results suggest that ch-Cpn21 may play a role in seed abortion in stenospermocarpic grapes.

  11. A comparison of biomarker responses in juvenile diploid and ...

    EPA Pesticide Factsheets

    Influence of waterborne butachlor (BUC), a commonly used pesticide, on morphometric, biochemical, and molecular biomarkers was evaluated in juvenile, full sibling, diploid and triploid African catfish (Clarias gariepinus). Fish were exposed for 21 days to one of three concentrations of BUC [mean measured µg/L: 22, 44 or 60]. Unexposed (control) triploids were heavier and longer and had higher visceral-somatic index (VSI) than diploids. Also, they had lighter liver weight (HSI) and showed lower transcript levels of brain gonadotropin-releasing hormone (GnRH), aromatase (cyp191b) and fushi tarazu-factor (ftz-f1), and plasma testosterone levels than diploids. Butachlor treatments had no effects, in either diploid or triploid fish, on VSI, HSI, weight or length changes, condition factor (CF), levels of plasma testosterone, 17-β estradiol (E2), cortisol, cholesterol, or mRNA levels of brain tryptophan hydroxylase (tph2), forkhead box L2 (foxl2), and 11 β-hydroxysteroid dehydrogenase type 2 (11β-hsd2). Expressions of cyp191b and ftz-f1 in triploids were upregulated by the two highest concentrations of BUC. In diploid fish, however, exposures to all BUC concentrations decreased GnRH transcription and the medium BUC concentration decreased ftz-f1 transcription. Substantial differences between ploidies in basal biomarker responses are consistent with the reported impaired reproductive axis in triploid C. gariepinus. Furthermore, the present study showed the low impac

  12. A comparison of biomarker responses in juvenile diploid and ...

    EPA Pesticide Factsheets

    Influence of waterborne butachlor (BUC), a commonly used pesticide, on morphometric, biochemical, and molecular biomarkers was evaluated in juvenile, full sibling, diploid and triploid African catfish (Clarias gariepinus). Fish were exposed for 21 days to one of three concentrations of BUC [mean measured µg/L: 22, 44 or 60]. Unexposed (control) triploids were heavier and longer and had higher visceral-somatic index (VSI) than diploids. Also, they had lighter liver weight (HSI) and showed lower transcript levels of brain gonadotropin-releasing hormone (GnRH), aromatase (cyp191b) and fushi tarazu-factor (ftz-f1), and plasma testosterone levels than diploids. Butachlor treatments had no effects, in either diploid or triploid fish, on VSI, HSI, weight or length changes, condition factor (CF), levels of plasma testosterone, 17-β estradiol (E2), cortisol, cholesterol, or mRNA levels of brain tryptophan hydroxylase (tph2), forkhead box L2 (foxl2), and 11 β-hydroxysteroid dehydrogenase type 2 (11β-hsd2). Expressions of cyp191b and ftz-f1 in triploids were upregulated by the two highest concentrations of BUC. In diploid fish, however, exposures to all BUC concentrations decreased GnRH transcription and the medium BUC concentration decreased ftz-f1 transcription. Substantial differences between ploidies in basal biomarker responses are consistent with the reported impaired reproductive axis in triploid C. gariepinus. Furthermore, the present study showed the low impac

  13. Fixation Probability in a Haploid-Diploid Population.

    PubMed

    Bessho, Kazuhiro; Otto, Sarah P

    2017-01-01

    Classical population genetic theory generally assumes either a fully haploid or fully diploid life cycle. However, many organisms exhibit more complex life cycles, with both free-living haploid and diploid stages. Here we ask what the probability of fixation is for selected alleles in organisms with haploid-diploid life cycles. We develop a genetic model that considers the population dynamics using both the Moran model and Wright-Fisher model. Applying a branching process approximation, we obtain an accurate fixation probability assuming that the population is large and the net effect of the mutation is beneficial. We also find the diffusion approximation for the fixation probability, which is accurate even in small populations and for deleterious alleles, as long as selection is weak. These fixation probabilities from branching process and diffusion approximations are similar when selection is weak for beneficial mutations that are not fully recessive. In many cases, particularly when one phase predominates, the fixation probability differs substantially for haploid-diploid organisms compared to either fully haploid or diploid species. Copyright © 2017 by the Genetics Society of America.

  14. Development of highly transparent seedless ZnO nanorods engineered for inverted polymer solar cells.

    PubMed

    Ambade, Swapnil B; Ambade, Rohan B; Lee, Wonjoo; Mane, Rajaram S; Yoon, Sung Cheol; Lee, Soo-Hyoung

    2014-10-21

    This work reports on inverted polymer solar cells (IPSCs) based on highly transparent (>95%), hydrophobic, seedless ZnO nanorods (NRs) as cathode buffers with extremely enhanced electrical characteristics. The transparent NR suspension with stability for more than a year is achieved by adding a small amount of 2-(2-methoxyethoxy) acetic acid (MEA). The ability of the stable nanorod suspension to easily spin-coat is certainly an advance to the fabrication of films over large areas and to replace the conventional seeding method to grow one-dimensional nanostructures for use in optoelectronic devices. We observe a strong correlation between the photovoltaic performance and the transparency of ZnO NRs. IPSCs using poly-3-hexylthiophene (P3HT) and [6,6]-phenyl C60 butyric acid methyl ester (PCBM) mixtures in the active layer and transparent (MEA-capped) ZnO NRs as cathode buffers exhibit a power conversion efficiency of 3.24% under simulated AM 1.5G, 100 mW cm(-2) illumination.

  15. Stenospermy and seed development in the "Brazilian seedless" variety of sugar apple (Annona squamosa).

    PubMed

    Dos Santos, Rayane C; Ribeiro, Leonardo M; Mercadante-Simões, Maria Olívia; Costa, Márcia R; Nietsche, Silvia; Pereira, Marlon C T

    2014-12-01

    Stenospermy was identified in naturally occurring sugar-apple (Annona squamosa) mutants with great potential for use in genetic improvement programs. However, to date, there have been no detailed studies of the development of aspermic fruit in this species. The aim of the present study was to characterize the anatomy of developing fruit in the 'Brazilian Seedless' mutant. Flower buds in pre-anthesis and developing fruits were subjected to common plant anatomy techniques. The abnormal ovules are unitegmic and orthotropic and have a long funiculus. There is evidence of fertilization, including the presence of embryos in early development and the proliferation of starch grains in the embryo sac. However, the embryos and embryo sac degenerate, although this does not affect pericarp development. Ovule abortion does not occur. The perisperm, which is formed from the peripheral layers of the nucellus, fills the cavity left by the embryo sac. The mature fruit contains numerous small sterile seeds with abundant perisperm and unlignified integument that is restricted to the micropylar region. The majority of perisperm cells are living and appear to be metabolically active in the periphery. Therefore, stenospermy leads to the formation of sterile seeds in A. squamosa, and the perisperm possibly play an important role in fruit development.

  16. Seedless synthesis of nanocomposites, optical properties, and effects of additives on their surface resonance plasmon bands

    NASA Astrophysics Data System (ADS)

    Zaheer, Zoya; Aazam, Elham Shafik

    2017-07-01

    The work describes an easy seedless competitive chemical reduction method for the synthesis of Ag@Au/Ag bimetallic nanoparticles by mixing AgNO3, HAuCl4 and cysteine. Transmission electron microscope (TEM) images show that the large number of irregular, cross-linking, and aggregated Ag@Au/Ag are formed in a reaction mixture (HAuCl4 + AgNO3 + cysteine), whereas flower-like nanocomposites are obtained in presence of cetyltrimethylammonium bromide (CTAB), which acted as a shape-directing agent. Optical images reveal that the initially reaction proceeds through formation of purple color, which changes into dark brown color with the reaction time, indicating the formation of Ag@Au/Ag nanocomposites. The Ag+ has strong tendency to form complex with cysteine. Firstly, the reduction of Ag+ ions to Ag0 occurred by the sbnd HSsbnd group of the cysteine-Ag complex. Secondly, AuCl4- ions adsorbed on the positive surface of Ag0, which undergoes reduction by potential deposition, and leads to the formation of Ag@Au/Ag bimetallic nanoparticles. Inorganic electrolytes (NaCl, NaBr, NaNO3 and Na2SO4) have significant impact on the stability and aggregation of Ag@Au/Ag nanocomposites.

  17. Seedless synthesis of nanocomposites, optical properties, and effects of additives on their surface resonance plasmon bands.

    PubMed

    Zaheer, Zoya; Aazam, Elham Shafik

    2017-04-03

    The work describes an easy seedless competitive chemical reduction method for the synthesis of Ag@Au/Ag bimetallic nanoparticles by mixing AgNO3, HAuCl4 and cysteine. Transmission electron microscope (TEM) images show that the large number of irregular, cross-linking, and aggregated Ag@Au/Ag are formed in a reaction mixture (HAuCl4+AgNO3+cysteine), whereas flower-like nanocomposites are obtained in presence of cetyltrimethylammonium bromide (CTAB), which acted as a shape-directing agent. Optical images reveal that the initially reaction proceeds through formation of purple color, which changes into dark brown color with the reaction time, indicating the formation of Ag@Au/Ag nanocomposites. The Ag(+) has strong tendency to form complex with cysteine. Firstly, the reduction of Ag(+) ions to Ag(0) occurred by the HS group of the cysteine-Ag complex. Secondly, AuCl4(-) ions adsorbed on the positive surface of Ag(0), which undergoes reduction by potential deposition, and leads to the formation of Ag@Au/Ag bimetallic nanoparticles. Inorganic electrolytes (NaCl, NaBr, NaNO3 and Na2SO4) have significant impact on the stability and aggregation of Ag@Au/Ag nanocomposites.

  18. Seedless growth of zinc oxide flower-shaped structures on multilayer graphene by electrochemical deposition

    PubMed Central

    2014-01-01

    A seedless growth of zinc oxide (ZnO) structures on multilayer (ML) graphene by electrochemical deposition without any pre-deposited ZnO seed layer or metal catalyst was studied. A high density of a mixture of vertically aligned/non-aligned ZnO rods and flower-shaped structures was obtained. ML graphene seems to generate the formation of flower-shaped structures due to the stacking boundaries. The nucleation of ZnO seems to be promoted at the stacking edges of ML graphene with the increase of applied current density, resulting in the formation of flower-shaped structures. The diameters of the rods/flower-shaped structures also increase with the applied current density. ZnO rods/flower-shaped structures with high aspect ratio over 5.0 and good crystallinity were obtained at the applied current densities of −0.5 and −1.0 mA/cm2. The growth mechanism was proposed. The growth involves the formation of ZnO nucleation below 80°C and the enhancement of the growth of vertically non-aligned rods and flower-shaped structures at 80°C. Such ZnO/graphene hybrid structure provides several potential applications in sensing devices. PMID:25024694

  19. Seedless growth of zinc oxide flower-shaped structures on multilayer graphene by electrochemical deposition.

    PubMed

    Aziz, Nur Suhaili Abd; Nishiyama, Tomoya; Rusli, Nurul Izni; Mahmood, Mohamad Rusop; Yasui, Kanji; Hashim, Abdul Manaf

    2014-01-01

    A seedless growth of zinc oxide (ZnO) structures on multilayer (ML) graphene by electrochemical deposition without any pre-deposited ZnO seed layer or metal catalyst was studied. A high density of a mixture of vertically aligned/non-aligned ZnO rods and flower-shaped structures was obtained. ML graphene seems to generate the formation of flower-shaped structures due to the stacking boundaries. The nucleation of ZnO seems to be promoted at the stacking edges of ML graphene with the increase of applied current density, resulting in the formation of flower-shaped structures. The diameters of the rods/flower-shaped structures also increase with the applied current density. ZnO rods/flower-shaped structures with high aspect ratio over 5.0 and good crystallinity were obtained at the applied current densities of -0.5 and -1.0 mA/cm(2). The growth mechanism was proposed. The growth involves the formation of ZnO nucleation below 80°C and the enhancement of the growth of vertically non-aligned rods and flower-shaped structures at 80°C. Such ZnO/graphene hybrid structure provides several potential applications in sensing devices.

  20. Molecular cloning, sequence characterization and expression pattern of Rab18 gene from watermelon (Citrullus lanatus).

    PubMed

    Xinli, Xiao; Lei, Peng

    2015-03-04

    The complete mRNA sequence of watermelon Rab18 gene was amplified through the rapid amplification of cDNA ends (RACE) method. The full-length mRNA was 1010 bp containing a 645 bp open reading frame, which encodes a protein of 214 amino acids. Sequence analysis revealed that watermelon Rab18 protein shares high homology with the Rab18 of cucumber (99%), muskmelon (98%), Morus notabilis (90%), tomato (89%), wine grape (89%) and potato (88%). Phylogenetic analysis revealed that watermelon Rab18 gene has a closer genetic relationship with Rab18 gene of cucumber and muskmelon. Tissue expression profile analysis indicated that watermelon Rab18 gene was highly expressed in root, stem and leaf, moderately expressed in flower and weakly expressed in fruit.

  1. Infection Courts in Watermelon Plants Leading to Seed Infestation by Fusarium oxysporum f. sp. niveum.

    PubMed

    Petkar, Aparna; Ji, Pingsheng

    2017-07-01

    Fusarium wilt incited by Fusarium oxysporum f. sp. niveum is a seed-transmitted disease that causes significant yield loss in watermelon production. The pathogen may infect watermelon seeds latently, which can be an important inoculum source and contribute to severe disease outbreak. However, information regarding infection courts of F. oxysporum f. sp. niveum leading to infestation of watermelon seeds is limited. To determine how seeds in watermelon fruit can be infested by F. oxysporum f. sp. niveum during the watermelon growing season, greenhouse and field experiments were conducted in 2014 and 2015 where watermelon flowers and immature fruit were inoculated with F. oxysporum f. sp. niveum. Seeds were extracted from mature watermelon fruit, and infestation of watermelon seeds was determined by isolation of F. oxysporum f. sp. niveum and further confirmed by real-time polymerase chain reaction (PCR) analysis. Inoculation of the pericarp of immature fruit resulted in 17.8 to 54.4% of infested seeds under field conditions and 0.6 to 12.8% of infested seeds under greenhouse conditions when seeds were not surface disinfested prior to isolation. Seed infestation was also detected in 0 to 4.5% of the seeds when seeds were surface disinfested prior to isolation. Inoculation of pistil resulted in 0 to 7.2% and 0 to 18.3% of infested seeds under greenhouse and field conditions when seeds were surface disinfested or not disinfested before isolation, respectively. Inoculation of peduncle resulted in 0.6 to 6.1% and 0 to 10.0% of infested seeds in the greenhouse and field experiments when seeds were surface disinfested or not disinfested before isolation, respectively. Seed infestation was also detected in all the experiments using real-time PCR assay when pericarp or pistil was inoculated, and in three of four experiments when peduncle was inoculated, regardless of whether seeds were surface disinfested or not disinfested. Pericarp and peduncle of immature watermelon fruit

  2. Powerful decomposition of complex traits in a diploid model

    PubMed Central

    Hallin, Johan; Märtens, Kaspar; Young, Alexander I.; Zackrisson, Martin; Salinas, Francisco; Parts, Leopold; Warringer, Jonas; Liti, Gianni

    2016-01-01

    Explaining trait differences between individuals is a core and challenging aim of life sciences. Here, we introduce a powerful framework for complete decomposition of trait variation into its underlying genetic causes in diploid model organisms. We sequence and systematically pair the recombinant gametes of two intercrossed natural genomes into an array of diploid hybrids with fully assembled and phased genomes, termed Phased Outbred Lines (POLs). We demonstrate the capacity of this approach by partitioning fitness traits of 6,642 Saccharomyces cerevisiae POLs across many environments, achieving near complete trait heritability and precisely estimating additive (73%), dominance (10%), second (7%) and third (1.7%) order epistasis components. We map quantitative trait loci (QTLs) and find nonadditive QTLs to outnumber (3:1) additive loci, dominant contributions to heterosis to outnumber overdominant, and extensive pleiotropy. The POL framework offers the most complete decomposition of diploid traits to date and can be adapted to most model organisms. PMID:27804950

  3. Comparative mapping in watermelon [Citrullus lanatus (Thunb.) Matsum. et Nakai].

    PubMed

    Sandlin, Katherine; Prothro, Jason; Heesacker, Adam; Khalilian, Nelly; Okashah, Rebecca; Xiang, Wenwen; Bachlava, Eleni; Caldwell, David G; Taylor, Chris A; Seymour, Danelle K; White, Victoria; Chan, Eva; Tolla, Greg; White, Cathy; Safran, Dolores; Graham, Elaine; Knapp, Steven; McGregor, Cecilia

    2012-12-01

    The first single-nucleotide polymorphism (SNP) maps for watermelon [Citrullus lanatus (Thunb.) Matsum. et Nakai] were constructed and compared. Three populations were developed from crosses between two elite cultivars, Klondike Black Seeded × New Hampshire Midget (KBS × NHM), an elite cultivar and wild egusi accession, Strain II × PI 560023 (SII × Egusi) and an elite cultivar and a wild citron accession, ZWRM50 × PI 244019 (ZWRM × Citroides). The SII × Egusi and ZWRM × Citroides F(2) populations consisted of 187 and 182 individuals respectively while the KBS × NHM recombinant inbred line (RIL) population consisted of 164 lines. The length of the genetic maps were 1,438, 1,514 and 1,144 cM with average marker distances of 3.8, 4.2, and 3.4 cM for the KBS × NHM, SII × Egusi and ZWRM × Citroides populations, respectively. Shared markers were used to align the three maps so that the linkage groups (LGs) represented the 11 chromosomes of the species. Marker segregation distortion were observed in all three populations, but was highest (12.7 %) in the ZWRM × Citroides population, where Citroides alleles were favored. The three maps were used to construct a consensus map containing 378 SNP markers with an average distance of 5.1 cM between markers. Phenotypic data was collected for fruit weight (FWT), fruit length (FL), fruit width (FWD), fruit shape index (FSI), rind thickness (RTH) and Brix (BRX) and analyzed for quantitative trait loci (QTL) associated with these traits. A total of 40 QTL were identified in the three populations, including major QTL for fruit size and shape that were stable across genetic backgrounds and environments. The present study reports the first SNP maps for Citrullus and the first map constructed using two elite parents. We also report the first stable QTL associated with fruit size and shape in Citrullus lanatus. These maps, QTL and SNPs should be useful for the watermelon community and represent a significant step towards the

  4. Nitric oxide protects carbon assimilation process of watermelon from boron-induced oxidative injury.

    PubMed

    Farag, Mohamed; Najeeb, Ullah; Yang, Jinghua; Hu, Zhongyuan; Fang, Zhang Ming

    2017-02-01

    Nitric oxide (NO) mediates plant response to a variety of abiotic stresses; however, limited information is available on its effect on boron (B)-stressed watermelon plants. The present study investigates the mechanism through which NO protects watermelon seedlings from B deficiency and toxicity stresses. Five days old watermelon seedlings were exposed to B (0, 0.5 and 10 mg L(-1)) alone or with 75 μmole of NO donor sodium nitroprusside (SNP) for 30 days. Both low and high B concentrations in the media altered nutrient accumulation and impaired various physiological processes of watermelon seedlings, leading to a significant reduction in biomass production. The plants exposed to B deficient or toxic concentrations had 66 and 69% lower shoot dry weight, respectively compared with optimum B levels. B toxicity-induced growth inhibition of watermelon seedlings was associated with high B translocation to shoot tissues, which caused lipid membrane peroxidation (12% increase) and chlorophyll destruction (25% reduction). In contrast, B deficiency accelerated generation of reactive oxygen species (ROS), specifically OH(-1) and induced cellular oxidative injury. Exogenously applied SNP promoted leaf chlorophyll, photosynthesis and consequently biomass production in B-stressed watermelon seedlings by reducing B accumulation, lipid membrane peroxidation and ROS generation. It also activated antioxidant enzymes such as SOD, POD and APX, and protected the seedlings from ROS-induced cellular burst.

  5. Standardized Sampling Plan for the Thrips Frankliniella schultzei (Thysanoptera: Thripidae) on Watermelon Crops.

    PubMed

    Barbosa Pinto, Cleovan; Almeida Sarmento, Renato; Visintin da Silva Galdino, Tarcísio; Silvestre Pereira, Poliana; Gomes Barbosa, Breno; Henrique Oliveira Lima, Carlos; Rodrigues da Silva, Nilson; Coutinho Picanço, Marcelo

    2017-04-01

    Sampling plans are essential components of integrated pest management programs. The thrips Frankliniella schultzei (Trybom) (Thysanoptera: Thripidae) is an important pest of watermelon crops. Despite the importance of sampling plans and of F. schultzei as a pest of watermelon crops, no research has been previously conducted on this subject for this crop. The objective of this work was to create a standardized sampling plan for F. schultzei in watermelon crops. Over two consecutive years, weekly samplings were performed in commercial watermelon crops. The aim of these assessments was to select the best sampling unit and the best sampling technique for F. schultzei assessment and to determine the number of samples necessary for a standardized sampling plan for this pest. In watermelon crops in the vegetative, flowering, and fruiting stages, the ideal location for sampling F. schultzei was the most apical leaf of the branches. The best sampling technique was a direct count of F. schultzei individuals. The F. schultzei sampling plan involved the evaluation of 69 samples per plot. The execution duration of this sampling plan in 1- to 15-ha plots was <1 h and was inexpensive (watermelon before. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Direction of illumination controls gametophyte orientation in seedless plants and related algae

    PubMed Central

    Cardona-Correa, Christopher; Ecker, Alice; Graham, Linda E

    2015-01-01

    The environmental influences that determine dorsiventral or axial gametophyte orientation are unknown for most modern seedless plants. To fill this gap, an experimental laboratory system was employed to evaluate the relative effects of light direction and gravity on body orientation of the dorsiventral green alga Coleochaete orbicularis, and gametophytes of liverworts Blasia pusilla and Marchantia polymorpha, early-diverging moss Sphagnum compactum, and fern Ceratopteris richardii, the latter functioning as experimental control. Replicate clonal cultures were experimentally illuminated only from above, only from below, or from multiple directions, with the same near-saturation PAR level for periods brief enough to minimize nutrient limitation effects, and orientation of new growth was evaluated. For all species tested, direction of illumination exerted stronger control over gametophyte body orientation than gravity. When illuminated only from below: 1) axial Sphagnum gametophores that had initially grown into an overlying air space inverted growth by 180°, burrowing into the substrate; 2) new growth of dorsiventral Blasia, Marchantia, and Ceratopteris gametophytes–whose ventral rhizoids initially penetrated agar substrate and dorsal surfaces initially faced overlying airspace–twisted 180° so that ventral surfaces bearing rhizoids faced overlying air space and rhizoids extended into the air; and 3) Coleochaete lost typical dorsiventral organization and diagnostic dorsal hairs. Direction of illumination also exerted stronger control over orientation of liverwort new growth than surface contact did. These results indicate that early land plants likely inherited light-directed gametophyte body orientation from ancestral streptophyte algae and suggest a mechanism for reorientation of gametophyte-dominant land plants after spatial disturbance. PMID:26237278

  7. Synthesis and optical properties of small Au nanorods using a seedless growth technique.

    PubMed

    Ali, Moustafa R K; Snyder, Brian; El-Sayed, Mostafa A

    2012-06-26

    Gold nanoparticles have shown potential in photothermal cancer therapy and optoelectronic technology. In both applications, a call for small size nanorods is warranted. In the present work, a one-pot seedless synthetic technique has been developed to prepare relatively small monodisperse gold nanorods with average dimensions (length × width) of 18 × 4.5 nm, 25 × 5 nm, 15 × 4.5 nm, and 10 × 2.5 nm. In this method, the pH was found to play a crucial role in the monodispersity of the nanorods when the NaBH(4) concentration of the growth solution was adjusted to control the reduction rate of the gold ions. At the optimized pH and NaBH(4) concentrations, smaller gold nanorods were produced by adjusting the CTAB concentration in the growth solution. In addition, the concentration of silver ions in the growth solution was found to be pivotal in controlling the aspect ratio of the nanorods. The extinction coefficient values for the small gold nanorods synthesized with three different aspect ratios were estimated using the absorption spectra, size distributions, and the atomic spectroscopic analysis data. The previously accepted relationships between the extinction coefficient or the longitudinal band wavelength values and the nanorods' aspect ratios found for the large nanorods do not extend to the small size domain reported in the present work. The failure of extending these relationships over larger sizes is a result of the interaction of light with the large rods giving an extinction band which results mostly from scattering processes while the extinction of the small nanorods results from absorption processes.

  8. Open field trial of genetically modified parthenocarpic tomato: seedlessness and fruit quality

    PubMed Central

    Rotino, Giuseppe Leonardo; Acciarri, Nazareno; Sabatini, Emidio; Mennella, Giuseppe; Lo Scalzo, Roberto; Maestrelli, Andrea; Molesini, Barbara; Pandolfini, Tiziana; Scalzo, Jessica; Mezzetti, Bruno; Spena, Angelo

    2005-01-01

    Background Parthenocarpic tomato lines transgenic for the DefH9-RI-iaaM gene have been cultivated under open field conditions to address some aspects of the equivalence of genetically modified (GM) fruit in comparison to controls (non-GM). Results Under open field cultivation conditions, two tomato lines (UC 82) transgenic for the DefH9-RI-iaaM gene produced parthenocarpic fruits. DefH9-RI-iaaM fruits were either seedless or contained very few seeds. GM fruit quality, with the exception of a higher β-carotene level, did not show any difference, neither technological (colour, firmness, dry matter, °Brix, pH) nor chemical (titratable acidity, organic acids, lycopene, tomatine, total polyphenols and antioxidant capacity – TEAC), when compared to that of fruits from control line. Highly significant differences in quality traits exist between the tomato F1 commercial hybrid Allflesh and the three UC 82 genotypes tested, regardless of whether or not they are GM. Total yield per plant did not differ between GM and parental line UC 82. Fruit number was increased in GM lines, and GM fruit weight was decreased. Conclusion The use in the diet of fruits from a new line or variety introduces much greater changes than the consumption of GM fruits in comparison to its genetic background. Parthenocarpic fruits, produced under open field conditions, contained 10-fold less seeds than control fruits. Thus parthenocarpy caused by DefH9-RI-iaaM gene represents also a tool for mitigating GM seeds dispersal in the environment. PMID:16371162

  9. Open field trial of genetically modified parthenocarpic tomato: seedlessness and fruit quality.

    PubMed

    Rotino, Giuseppe Leonardo; Acciarri, Nazareno; Sabatini, Emidio; Mennella, Giuseppe; Lo Scalzo, Roberto; Maestrelli, Andrea; Molesini, Barbara; Pandolfini, Tiziana; Scalzo, Jessica; Mezzetti, Bruno; Spena, Angelo

    2005-12-21

    Parthenocarpic tomato lines transgenic for the DefH9-RI-iaaM gene have been cultivated under open field conditions to address some aspects of the equivalence of genetically modified (GM) fruit in comparison to controls (non-GM). Under open field cultivation conditions, two tomato lines (UC 82) transgenic for the DefH9-RI-iaaM gene produced parthenocarpic fruits. DefH9-RI-iaaM fruits were either seedless or contained very few seeds. GM fruit quality, with the exception of a higher beta-carotene level, did not show any difference, neither technological (colour, firmness, dry matter, degrees Brix, pH) nor chemical (titratable acidity, organic acids, lycopene, tomatine, total polyphenols and antioxidant capacity - TEAC), when compared to that of fruits from control line. Highly significant differences in quality traits exist between the tomato F1 commercial hybrid Allflesh and the three UC 82 genotypes tested, regardless of whether or not they are GM. Total yield per plant did not differ between GM and parental line UC 82. Fruit number was increased in GM lines, and GM fruit weight was decreased. The use in the diet of fruits from a new line or variety introduces much greater changes than the consumption of GM fruits in comparison to its genetic background. Parthenocarpic fruits, produced under open field conditions, contained 10-fold less seeds than control fruits. Thus parthenocarpy caused by DefH9-RI-iaaM gene represents also a tool for mitigating GM seeds dispersal in the environment.

  10. Direction of illumination controls gametophyte orientation in seedless plants and related algae.

    PubMed

    Cardona-Correa, Christopher; Ecker, Alice; Graham, Linda E

    2015-01-01

    The environmental influences that determine dorsiventral or axial gametophyte orientation are unknown for most modern seedless plants. To fill this gap, an experimental laboratory system was employed to evaluate the relative effects of light direction and gravity on body orientation of the dorsiventral green alga Coleochaete orbicularis, and gametophytes of liverworts Blasia pusilla and Marchantia polymorpha, early-diverging moss Sphagnum compactum, and fern Ceratopteris richardii, the latter functioning as experimental control. Replicate clonal cultures were experimentally illuminated only from above, only from below, or from multiple directions, with the same near-saturation PAR level for periods brief enough to minimize nutrient limitation effects, and orientation of new growth was evaluated. For all species tested, direction of illumination exerted stronger control over gametophyte body orientation than gravity. When illuminated only from below: 1) axial Sphagnum gametophores that had initially grown into an overlying air space inverted growth by 180°, burrowing into the substrate; 2) new growth of dorsiventral Blasia, Marchantia, and Ceratopteris gametophytes-whose ventral rhizoids initially penetrated agar substrate and dorsal surfaces initially faced overlying airspace-twisted 180° so that ventral surfaces bearing rhizoids faced overlying air space and rhizoids extended into the air; and 3) Coleochaete lost typical dorsiventral organization and diagnostic dorsal hairs. Direction of illumination also exerted stronger control over orientation of liverwort new growth than surface contact did. These results indicate that early land plants likely inherited light-directed gametophyte body orientation from ancestral streptophyte algae and suggest a mechanism for reorientation of gametophyte-dominant land plants after spatial disturbance.

  11. Selection on meiosis genes in diploid and tetraploid Arabidopsis arenosa.

    PubMed

    Wright, Kevin M; Arnold, Brian; Xue, Katherine; Šurinová, Maria; O'Connell, Jeremy; Bomblies, Kirsten

    2015-04-01

    Meiotic chromosome segregation is critical for fertility across eukaryotes, and core meiotic processes are well conserved even between kingdoms. Nevertheless, recent work in animals has shown that at least some meiosis genes are highly diverse or strongly differentiated among populations. What drives this remains largely unknown. We previously showed that autotetraploid Arabidopsis arenosa evolved stable meiosis, likely through reduced crossover rates, and that associated with this there is strong evidence for selection in a subset of meiosis genes known to affect axis formation, synapsis, and crossover frequency. Here, we use genome-wide data to study the molecular evolution of 70 meiosis genes in a much wider sample of A. arenosa. We sample the polyploid lineage, a diploid lineage from the Carpathian Mountains, and a more distantly related diploid lineage from the adjacent, but biogeographically distinct Pannonian Basin. We find that not only did selection act on meiosis genes in the polyploid lineage but also independently on a smaller subset of meiosis genes in Pannonian diploids. Functionally related genes are targeted by selection in these distinct contexts, and in two cases, independent sweeps occurred in the same loci. The tetraploid lineage has sustained selection on more genes, has more amino acid changes in each, and these more often affect conserved or potentially functional sites. We hypothesize that Pannonian diploid and tetraploid A. arenosa experienced selection on structural proteins that mediate sister chromatid cohesion, the formation of meiotic chromosome axes, and synapsis, likely for different underlying reasons.

  12. Genotyping by sequencing of a diploid potato F2 population

    USDA-ARS?s Scientific Manuscript database

    Genotyping-by-sequencing (GBS) of multiplexed, restriction-site associated DNA (RAD) libraries is an attractive technology for generating genome-wide markers because of its technical simplicity and low costs per sample. To investigate its feasibility for potato, a diploid F2 population (S. tuberosum...

  13. Selection on Meiosis Genes in Diploid and Tetraploid Arabidopsis arenosa

    PubMed Central

    Wright, Kevin M.; Arnold, Brian; Xue, Katherine; Šurinová, Maria; O’Connell, Jeremy; Bomblies, Kirsten

    2015-01-01

    Meiotic chromosome segregation is critical for fertility across eukaryotes, and core meiotic processes are well conserved even between kingdoms. Nevertheless, recent work in animals has shown that at least some meiosis genes are highly diverse or strongly differentiated among populations. What drives this remains largely unknown. We previously showed that autotetraploid Arabidopsis arenosa evolved stable meiosis, likely through reduced crossover rates, and that associated with this there is strong evidence for selection in a subset of meiosis genes known to affect axis formation, synapsis, and crossover frequency. Here, we use genome-wide data to study the molecular evolution of 70 meiosis genes in a much wider sample of A. arenosa. We sample the polyploid lineage, a diploid lineage from the Carpathian Mountains, and a more distantly related diploid lineage from the adjacent, but biogeographically distinct Pannonian Basin. We find that not only did selection act on meiosis genes in the polyploid lineage but also independently on a smaller subset of meiosis genes in Pannonian diploids. Functionally related genes are targeted by selection in these distinct contexts, and in two cases, independent sweeps occurred in the same loci. The tetraploid lineage has sustained selection on more genes, has more amino acid changes in each, and these more often affect conserved or potentially functional sites. We hypothesize that Pannonian diploid and tetraploid A. arenosa experienced selection on structural proteins that mediate sister chromatid cohesion, the formation of meiotic chromosome axes, and synapsis, likely for different underlying reasons. PMID:25543117

  14. Assay for mutagenesis in heterozygous diploid human lymphoblasts

    DOEpatents

    Skopek, Thomas R.; Liber, Howard L.; Penman, Bruce W.; Thilly, William G.; Hoppe, IV, Henry

    1981-01-01

    An assay is disclosed for determining mutagenic damage caused by the administration of a known or suspected mutagen to diploid human lymphoblastoid cell lines. The gene locus employed for this assay is the gene for thymidine kinase, uridine kinase, or cytidine deaminase. Since human lymphoblastoid cells contain two genes for these enzymes, heterozygotes of human lymphoblastoid cells are used in this assay.

  15. 'Don' a Diploid Falcata Alfalfa for Western US Rangelands

    USDA-ARS?s Scientific Manuscript database

    'Don' (Reg. No. CV-______, PI _______) a diploid falcata alfalfa (Medicago sativa subsp falcata L.) developed by the Forage and Range Research Laboratory in Logan, Utah, in cooperation with the Utah Agricultural Experiment Station, Utah State University. Recent interest in falcata alfalfa has been ...

  16. Does hybridization drive the transition to asexuality in diploid Boechera?

    PubMed

    Beck, James B; Alexander, Patrick J; Allphin, Loreen; Al-Shehbaz, Ihsan A; Rushworth, Catherine; Bailey, C Donovan; Windham, Michael D

    2012-04-01

    Gametophytic apomixis is a common form of asexual reproduction in plants. Virtually all gametophytic apomicts are polyploids, and some view polyploidy as a prerequisite for the transition to apomixis. However, any causal link between apomixis and polyploidy is complicated by the fact that most apomictic polyploids are allopolyploids, leading some to speculate that hybridization, rather than polyploidy, enables apomixis. Diploid apomixis presents a rare opportunity to isolate the role of hybridization, and a number of diploid apomicts have been documented in the genus Boechera (Brassicaceae). Here, we present the results of a microsatellite study of 1393 morphologically and geographically diverse diploid individuals, evaluating the hypothesis that diploid Boechera apomicts are hybrids. This genus-wide dataset was made possible by the applicability of a core set of microsatellite loci in 69 of the 70 diploid Boechera species and by our ability to successfully genotype herbarium specimens of widely varying ages. With few exceptions, diploid apomicts exhibited markedly high levels of heterozygosity resulting from the combination of disparate genomes. This strongly suggests that most apomictic diploid Boechera lineages are of hybrid origin, and that the genomic consequences of hybridization allow for the transition to gametophytic apomixis in this genus.

  17. No Need to Discriminate? Reproductive Diploid Males in a Parasitoid with Complementary Sex Determination

    PubMed Central

    Elias, Jan; Mazzi, Dominique; Dorn, Silvia

    2009-01-01

    Diploid males in hymenopterans are generally either inviable or sterile, thus imposing a severe genetic load on populations. In species with the widespread single locus complementary sex determination (sl-CSD), sex depends on the genotype at one single locus with multiple alleles. Haploid (hemizygous) individuals are always males. Diploid individuals develop into females when heterozygous and into males when homozygous at the sex determining locus. Our comparison of the mating and reproductive success of haploid and diploid males revealed that diploid males of the braconid parasitoid Cotesia glomerata sire viable and fertile diploid daughters. Females mated to diploid males, however, produced fewer daughters than females mated to haploid males. Nevertheless, females did not discriminate against diploid males as mating partners. Diploid males initiated courtship display sooner than haploid males and were larger in body size. Although in most species so far examined diploid males were recognized as genetic dead ends, we present a second example of a species with sl-CSD and commonly occurring functionally reproductive diploid males. Our study suggests that functionally reproductive diploid males might not be as rare as hitherto assumed. We argue that the frequent occurrence of inbreeding in combination with imperfect behavioural adaptations towards its avoidance promote the evolution of diploid male fertility. PMID:19551142

  18. Origin and genetic diversity of diploid parthenogenetic Artemia in Eurasia.

    PubMed

    Maccari, Marta; Amat, Francisco; Gómez, Africa

    2013-01-01

    There is wide interest in understanding how genetic diversity is generated and maintained in parthenogenetic lineages, as it will help clarify the debate of the evolution and maintenance of sexual reproduction. There are three mechanisms that can be responsible for the generation of genetic diversity of parthenogenetic lineages: contagious parthenogenesis, repeated hybridization and microorganism infections (e.g. Wolbachia). Brine shrimps of the genus Artemia (Crustacea, Branchiopoda, Anostraca) are a good model system to investigate evolutionary transitions between reproductive systems as they include sexual species and lineages of obligate parthenogenetic populations of different ploidy level, which often co-occur. Diploid parthenogenetic lineages produce occasional fully functional rare males, interspecific hybridization is known to occur, but the mechanisms of origin of asexual lineages are not completely understood. Here we sequenced and analysed fragments of one mitochondrial and two nuclear genes from an extensive set of populations of diploid parthenogenetic Artemia and sexual species from Central and East Asia to investigate the evolutionary origin of diploid parthenogenetic Artemia, and geographic origin of the parental taxa. Our results indicate that there are at least two, possibly three independent and recent maternal origins of parthenogenetic lineages, related to A. urmiana and Artemia sp. from Kazakhstan, but that the nuclear genes are very closely related in all the sexual species and parthenogegetic lineages except for A. sinica, who presumable took no part on the origin of diploid parthenogenetic strains. Our data cannot rule out either hybridization between any of the very closely related Asiatic sexual species or rare events of contagious parthenogenesis via rare males as the contributing mechanisms to the generation of genetic diversity in diploid parthenogenetic Artemia lineages.

  19. Origin and Genetic Diversity of Diploid Parthenogenetic Artemia in Eurasia

    PubMed Central

    Maccari, Marta; Amat, Francisco; Gómez, Africa

    2013-01-01

    There is wide interest in understanding how genetic diversity is generated and maintained in parthenogenetic lineages, as it will help clarify the debate of the evolution and maintenance of sexual reproduction. There are three mechanisms that can be responsible for the generation of genetic diversity of parthenogenetic lineages: contagious parthenogenesis, repeated hybridization and microorganism infections (e.g. Wolbachia). Brine shrimps of the genus Artemia (Crustacea, Branchiopoda, Anostraca) are a good model system to investigate evolutionary transitions between reproductive systems as they include sexual species and lineages of obligate parthenogenetic populations of different ploidy level, which often co-occur. Diploid parthenogenetic lineages produce occasional fully functional rare males, interspecific hybridization is known to occur, but the mechanisms of origin of asexual lineages are not completely understood. Here we sequenced and analysed fragments of one mitochondrial and two nuclear genes from an extensive set of populations of diploid parthenogenetic Artemia and sexual species from Central and East Asia to investigate the evolutionary origin of diploid parthenogenetic Artemia, and geographic origin of the parental taxa. Our results indicate that there are at least two, possibly three independent and recent maternal origins of parthenogenetic lineages, related to A. urmiana and Artemia sp. from Kazakhstan, but that the nuclear genes are very closely related in all the sexual species and parthenogegetic lineages except for A. sinica, who presumable took no part on the origin of diploid parthenogenetic strains. Our data cannot rule out either hybridization between any of the very closely related Asiatic sexual species or rare events of contagious parthenogenesis via rare males as the contributing mechanisms to the generation of genetic diversity in diploid parthenogenetic Artemia lineages. PMID:24376692

  20. Recombinant yeast as a functional tool for understanding bitterness and cucurbitacin biosynthesis in watermelon (Citrullus spp.).

    PubMed

    Davidovich-Rikanati, Rachel; Shalev, Lior; Baranes, Nadine; Meir, Ayala; Itkin, Maxim; Cohen, Shahar; Zimbler, Kobi; Portnoy, Vitaly; Ebizuka, Yutaka; Shibuya, Masaaki; Burger, Yosef; Katzir, Nurit; Schaffer, Arthur A; Lewinsohn, Efraim; Tadmor, Ya'akov

    2015-01-01

    Cucurbitacins are a group of bitter-tasting oxygenated tetracyclic triterpenes that are produced in the family Cucurbitaceae and other plant families. The natural roles of cucurbitacins in plants are probably related to defence against pathogens and pests. Cucurbitadienol, a triterpene synthesized from oxidosqualene, is the first committed precursor to cucurbitacins produced by a specialized oxidosqualene cyclase termed cucurbitadienol synthase. We explored cucurbitacin accumulation in watermelon in relation to bitterness. Our findings show that cucurbitacins are accumulated in bitter-tasting watermelon, Citrullus lanatus var. citroides, as well as in their wild ancestor, C. colocynthis, but not in non-bitter commercial cultivars of sweet watermelon (C. lanatus var. lanatus). Molecular analysis of genes expressed in the roots of several watermelon accessions led to the isolation of three sequences (CcCDS1, CcCDS2 and ClCDS1), all displaying high similarity to the pumpkin CpCPQ, encoding a protein previously shown to possess cucurbitadienol synthase activity. We utilized the Saccharomyces cerevisiae strain BY4743, heterozygous for lanosterol synthase, to probe for possible encoded cucurbitadienol synthase activity of the expressed watermelon sequences. Functional expression of the two sequences isolated from C. colocynthis (CcCDS1 and CcCDS2) in yeast revealed that only CcCDS2 possessed cucurbitadienol synthase activity, while CcCDS1 did not display cucurbitadienol synthase activity in recombinant yeast. ClCDS1 isolated from C. lanatus var. lanatus is almost identical to CcCDS1. Our results imply that CcCDS2 plays a role in imparting bitterness to watermelon. Yeast has been an excellent diagnostic tool to determine the first committed step of cucurbitacin biosynthesis in watermelon. Copyright © 2014 John Wiley & Sons, Ltd.

  1. Development of ZYMV-resistant watermelon lines using molecular markers for the eukaryotic elongation factor eIF4E together with phenotypic evaluation

    USDA-ARS?s Scientific Manuscript database

    The aphid-transmitted potyviruses of watermelon, including papaya ringspot virus (PRSV), watermelon mosaic virus (WMV), and zucchini yellow mosaic virus (ZYMV) cause serious damage to the watermelon crop throughout the world. The United States Plant Introduction (PI) 595203 is resistant to ZYMV-FL a...

  2. Preharvest salicylic acid treatments to improve quality and postharvest life of table grapes (Vitis vinifera L.) cv. Flame Seedless.

    PubMed

    Champa, W A Harindra; Gill, M I S; Mahajan, B V C; Arora, N K

    2015-06-01

    Significance of preharvest salicylic acid (SA) treatments on maturity, quality and postharvest life of grape cv. Flame Seedless were studied during two years. The experiment was performed on 12-year old own rooted, grapevines planted at 3 m × 3 m spacing trained on overhead system. Vines were treated with aqueous solutions of SA (0.0, 1.0, 1.5 and 2.0 mM) at pea stage and at veraison. After harvesting, clusters were divided into two lots in which one was subjected to initial quality evaluation, while the other was stored in cold room (3-4 °C, 90-95 % RH) for evaluation of postharvest quality. SA at the dose of 1.5 and 2.0 mM hastened berry maturity by 3 to 5 days, produced less compact bunches alongside larger berries in contrast to control and the lowest dose. The same doses effectively maintained peel colour, higher firmness, lower pectin methyl esterase activity and electrolyte leakage alongside suppressing degradation of TSS and TA during cold storage. These two doses also exhibited higher efficacy on maintaining anthocyanins, phenols and organoleptic properties while reducing weight loss, rachis browning and decay incidence. Correlation analysis demonstrated that many quality parameters are interdependent. In conclusion, preharvest spray of 1.5 mM SA proved to be an effective means of improving quality and extending postharvest life of grape cv. Flame Seedless.

  3. Changes in growth, photosynthetic activities, biochemical parameters and amino acid profile of Thompson Seedless grapes (Vitis vinifera L.).

    PubMed

    Somkuwar, R G; Bahetwar, Anita; Khan, I; Satisha, J; Ramteke, S D; Itroutwar, Prerna; Bhongale, Aarti; Oulkar, Dashrath

    2014-11-01

    The study on photosynthetic activity and biochemical parameters in Thompson Seedless grapes grafted on Dog Ridge rootstock and its impact on growth, yield and amino acid profile at various stages of berry development was conducted during the year 2012-2013. Leaf and berry samples from ten year old vines of Thompson Seedless were collected at different growth and berry developmental stages. The analysis showed difference in photosynthetic activity, biochemical parameters and amino acid status with the changes in berry development stage. Higher photosynthetic rate of 17.39 umol cm(-2) s(-1) was recorded during 3-4mm berry size and the lowest (10.08 umol cm(-2) s(-1)) was recorded during the veraison stage. The photosynthetic activity showed gradual decrease with the onset of harvest while the different biochemical parameters showed increase and decrease from one stage to another in both berry and leaves. Changes in photosynthetic activity and biochemical parameters thereby affected the growth, yield and amino acid content of the berry. Positive correlation of leaf area and photosynthetic rate was recorded during the period of study. Reducing sugar (352.25 mg g(-1)) and total carbohydrate (132.52 mg g(-1)) was more in berries as compared to leaf. Amino acid profile showed variations in different stages of berry development. Marked variations in photosynthetic as well as biochemical and amino acid content at various berry development stages was recorded and thereby its cumulative effect on the development of fruit quality.

  4. Effect of heat treatment, pH, sugar concentration, and metal addition on green color retention in homogenized puree of Thompson seedless grape

    USDA-ARS?s Scientific Manuscript database

    Homogenized puree of Thompson seedless (Vitis vinifera ‘Thompson Seedless’) grape was treated under different conditions, including heating time (5-30 min), temperature (20-80°C) and pH (2-10). Treatments with separate additions of glucose, fructose, and sucrose at concentrations of 100-600 g/L and ...

  5. Having a pair: the key to immune evasion for the diploid pathogen Schistosoma japonicum

    PubMed Central

    Xu, Xindong; Sun, Jun; Zhang, Jingjing; Wellems, Dianne; Qing, Xiaoxing; McCutchan, Thomas; Pan, Weiqing

    2012-01-01

    Schistosomes, unlike malaria parasites, are in their diploid stage when targeted by the human immune system. Diploids can be either homozygous or heterozygous. The difference has profound significance for developing immunity and yet has not previously been addressed. We examined the implications of zygosity on immunity to a diploid pathogen, Schistosoma japonicum and showed that the diploid state, and its associated heterozygous advantage, significantly affects the outcome of attack by the immune system and the accumulation of antigenic diversity in the parasite population. We demonstrate here that diploidy provides a novel means of immune evasion for diploid pathogens. PMID:22468230

  6. Influence of insecticides and reflective mulch on watermelon vine decline caused by squash vein yellowing virus (SqVYV)

    USDA-ARS?s Scientific Manuscript database

    Watermelon vine decline (WVD) caused by the whitefly-transmitted Squash vein yellowing virus (SqVYV) has been a major limiting factor in watermelon production in southwest and west-central Florida for the past several years. Symptoms of WVD typically manifest as sudden decline of vines a few weeks ...

  7. Identification and translocation of metabolites from powdery mildew resistant rootstocks to susceptible watermelon scions using nuclear magnetic resonance spectroscopy

    USDA-ARS?s Scientific Manuscript database

    Watermelon (Citrullus lanatus), an important commercial crop, and nutritious fruit, is high in antioxidants, vitamins, and lycopene. Powdery mildew (PM) is a serious disease caused by Podosphaera xanthii, which significantly reduces watermelon production in the U.S. and other parts of the world. C...

  8. 40 CFR 174.514 - Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. 174.514... Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. Residues of Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic...

  9. 40 CFR 174.514 - Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. 174.514... Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. Residues of Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic...

  10. 40 CFR 174.514 - Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. 174.514... Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. Residues of Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic...

  11. 40 CFR 174.514 - Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. 174.514... Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. Residues of Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic...

  12. 40 CFR 174.514 - Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. 174.514... Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. Residues of Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic...

  13. Diseases and their management strategies take top research priority in watermelon research and development group member’s survey

    USDA-ARS?s Scientific Manuscript database

    Watermelon is an important crop grown for its delicious fruit in the U.S. and in many countries across the world. A survey of members of Watermelon Research and Development Group (WRDG) was conducted via email and during WRDG meetings in 2014 and 2015 in an effort to identify and rank important rese...

  14. Progress in the Development of Crimson Sweet-type Watermelon Breeding Lines with Resistance to Acidovorax Avenae Subsp. Citrulli

    USDA-ARS?s Scientific Manuscript database

    Bacterial fruit blotch (Acidovorax avenae subsp. citrulli [Schaad et al.] Willems et al.) continues to occur almost every year and has the potential to cause a disaster for the watermelon industry. In this study, Crimson Sweet watermelon was crossed with PI482279 and PI494817, two Citrullus lanatus...

  15. First report of the cucurbit yellow vine disease caused by Serratia marcescens in watermelon and yellow squash in Alabama

    USDA-ARS?s Scientific Manuscript database

    Symptoms typical of cucurbit yellow vine disease (CYVD) were first observed in a 2 ha watermelon field in Crawford, Russell County, Alabama on 8 June 2010. Watermelon plants, cv. 'Jubilee,' exhibited a yellow or chlorotic appearance and some plants were completely wilted. On 24 June plant samples ...

  16. Biological Control of Bacterial Fruit Blotch of Watermelon Pathogen (Acidovorax citrulli) with Rhizosphere Associated Bacteria.

    PubMed

    Adhikari, Mahesh; Yadav, Dil Raj; Kim, Sang Woo; Um, Young Hyun; Kim, Hyun Seung; Lee, Seong Chan; Song, Jeong Young; Kim, Hong Gi; Lee, Youn Su

    2017-04-01

    Bacterial fruit blotch (BFB), which is caused by Acidovorax citrulli, is a serious threat to watermelon growers around the world. The present study was conducted to screen effective rhizobacterial isolates against 35 different A. citrulli isolates and determine their efficacy on BFB and growth parameters of watermelon. Two rhizobacterial isolates viz. Paenibacillus polymyxa (SN-22), Sinomonas atrocyanea (NSB-27) showed high inhibitory activity in the preliminary screening and were further evaluated for their effect on BFB and growth parameters of three different watermelon varieties under greenhouse conditions. The greenhouse experiment result revealed that SN-22 and NSB-27 significantly reduced BFB and had significant stimulatory effect on total chlorophyll content, plant height, total fresh weight and total dry weight compared to uninoculated plants across the tested three watermelon varieties. Analysis of the 16S ribosomal RNA (rRNA) sequences revealed that strains SN-22 belong to P. polymyxa and NSB-27 to S. atrocyanea with the bootstrap value of 99% and 98%, respectively. The isolates SN-22 and NSB-27 were tested for antagonistic and PGP traits. The result showed that the tested isolates produced siderophore, hydrolytic enzymes (protease and cellulose), chitinase, starch hydrolytic enzymes and they showed phosphate as well as zinc solubilizing capacity. This is the first report of P. polymyxa (SN-22) and S. atrocyanea (NSB-27) as biocontrol-plant growth promoting rhizobacteria on watermelon.

  17. Biological Control of Bacterial Fruit Blotch of Watermelon Pathogen (Acidovorax citrulli) with Rhizosphere Associated Bacteria

    PubMed Central

    Adhikari, Mahesh; Yadav, Dil Raj; Kim, Sang Woo; Um, Young Hyun; Kim, Hyun Seung; Lee, Seong Chan; Song, Jeong Young; Kim, Hong Gi; Lee, Youn Su

    2017-01-01

    Bacterial fruit blotch (BFB), which is caused by Acidovorax citrulli, is a serious threat to watermelon growers around the world. The present study was conducted to screen effective rhizobacterial isolates against 35 different A. citrulli isolates and determine their efficacy on BFB and growth parameters of watermelon. Two rhizobacterial isolates viz. Paenibacillus polymyxa (SN-22), Sinomonas atrocyanea (NSB-27) showed high inhibitory activity in the preliminary screening and were further evaluated for their effect on BFB and growth parameters of three different watermelon varieties under greenhouse conditions. The greenhouse experiment result revealed that SN-22 and NSB-27 significantly reduced BFB and had significant stimulatory effect on total chlorophyll content, plant height, total fresh weight and total dry weight compared to uninoculated plants across the tested three watermelon varieties. Analysis of the 16S ribosomal RNA (rRNA) sequences revealed that strains SN-22 belong to P. polymyxa and NSB-27 to S. atrocyanea with the bootstrap value of 99% and 98%, respectively. The isolates SN-22 and NSB-27 were tested for antagonistic and PGP traits. The result showed that the tested isolates produced siderophore, hydrolytic enzymes (protease and cellulose), chitinase, starch hydrolytic enzymes and they showed phosphate as well as zinc solubilizing capacity. This is the first report of P. polymyxa (SN-22) and S. atrocyanea (NSB-27) as biocontrol-plant growth promoting rhizobacteria on watermelon. PMID:28381964

  18. Characteristics and composition of watermelon, pumpkin, and paprika seed oils and flours.

    PubMed

    El-Adawy, T A; Taha, K M

    2001-03-01

    The nutritional quality and functional properties of paprika seed flour and seed kernel flours of pumpkin and watermelon were studied, as were the characteristics and structure of their seed oils. Paprika seed and seed kernels of pumpkin and watermelon were rich in oil and protein. All flour samples contained considerable amounts of P, K, Mg, Mn, and Ca. Paprika seed flour was superior to watermelon and pumpkin seed kernel flours in content of lysine and total essential amino acids. Oil samples had high amounts of unsaturated fatty acids with linoleic and oleic acids as the major acids. All oil samples fractionated into seven classes including triglycerides as a major lipid class. Data obtained for the oils' characteristics compare well with those of other edible oils. Antinutritional compounds such as stachyose, raffinose, verbascose, trypsin inhibitor, phytic acid, and tannins were detected in all flours. Pumpkin seed kernel flour had higher values of chemical score, essential amino acid index, and in vitro protein digestibility than the other flours examined. The first limiting amino acid was lysine for both watermelon and pumpkin seed kernel flours, but it was leucine in paprika seed flour. Protein solubility index, water and fat absorption capacities, emulsification properties, and foam stability were excellent in watermelon and pumpkin seed kernel flours and fairly good in paprika seed flour. Flour samples could be potentially added to food systems such as bakery products and ground meat formulations not only as a nutrient supplement but also as a functional agent in these formulations.

  19. Effect of chitosan solution on the inhibition of Acidovorax citrulli causing bacterial fruit blotch of watermelon.

    PubMed

    Li, Bin; Shi, Yu; Shan, Changlin; Zhou, Qing; Ibrahim, Muhammad; Wang, Yanli; Wu, Guoxing; Li, Hongye; Xie, Guanlin; Sun, Guochang

    2013-03-30

    The production of watermelon in China has been seriously hampered by fruit blotch disease and limited control measures are now applied. Chitosan has been employed to control a variety of plant diseases and is considered to be the most promising biochemical to control this disease. The in vitro antibacterial effect of chitosan and its ability in protection of watermelon seedlings from bacterial fruit blotch were evaluated. Results showed that three types of chitosan, in particular, chitosan A at 0.40 mg mL⁻¹ significantly inhibited the growth of Acidovorax citrulli. The antibacterial activity of chitosan A was affected by chitosan concentration and incubation time. The direct antibacterial activity of chitosan may be attributed to membrane lysis evidenced by transmission electron microscopic observation. The disease index of watermelon seedlings planted in soil and the death rate of seedlings planted in perlite were significantly reduced by chitosan A at 0.40 mg mL⁻¹ compared to the pathogen control. Fresh and dry weight of watermelon seedlings planted in soil was increased by chitosan seed treatment, but not by chitosan leaf spraying. The results indicated that chitosan solution may have a potential in controlling bacterial fruit blotch of watermelon. © 2013 Society of Chemical Industry.

  20. Antiviral activity of Thuja orientalis extracts against watermelon mosaic virus (WMV) on Citrullus lanatus

    PubMed Central

    Elbeshehy, Esam K.F.; Metwali, Ehab M.R.; Almaghrabi, Omar A.

    2014-01-01

    Watermelon mosaic potyvirus (WMV) is considered as an important virus infecting watermelon and causing adverse effects on crop productivity. To overcome this problem one of the main objectives of plant breeders is to make these strains less effective in the ability to infect plants by treatment with plant extracts. Due to the advantages of plant tissue culture, in vitro, in the process of the selection of different cultivars under biotic stress, this study was conducted to achieve this aim by evaluating the effect of three concentrations of Thuja extract on the multiplication of WMV in watermelon by measuring callus fresh weight and soluble proteins (mg g−1 fresh weight) of healthy and infected hypocotyl explants. Also, WMV was isolated from naturally infected watermelon and characterized as potyvirus by serological and molecular analyses. The isolated virus gave a positive reaction with WMV antiserum compared with other antibodies of CMV, ZYMV and SqMV using DAS-ELISA. RT-PCR, with the specific primer for WMV-cp. gene, yielded 825 base pair DNA fragments. The results that belong to soluble protein analysis indicated that infected hypocotyl explants treated with 6 g L−1 recorded the highest rate in the number of soluble protein bands compared with the rest of treatments. As a conclusion of these results, we can recommend to apply the Thuja extract at 6 g L−1 as a optimum dosage to decrease the infection caused by watermelon mosaic potyvirus. PMID:25737655

  1. Antiviral activity of Thuja orientalis extracts against watermelon mosaic virus (WMV) on Citrullus lanatus.

    PubMed

    Elbeshehy, Esam K F; Metwali, Ehab M R; Almaghrabi, Omar A

    2015-03-01

    Watermelon mosaic potyvirus (WMV) is considered as an important virus infecting watermelon and causing adverse effects on crop productivity. To overcome this problem one of the main objectives of plant breeders is to make these strains less effective in the ability to infect plants by treatment with plant extracts. Due to the advantages of plant tissue culture, in vitro, in the process of the selection of different cultivars under biotic stress, this study was conducted to achieve this aim by evaluating the effect of three concentrations of Thuja extract on the multiplication of WMV in watermelon by measuring callus fresh weight and soluble proteins (mg g(-1) fresh weight) of healthy and infected hypocotyl explants. Also, WMV was isolated from naturally infected watermelon and characterized as potyvirus by serological and molecular analyses. The isolated virus gave a positive reaction with WMV antiserum compared with other antibodies of CMV, ZYMV and SqMV using DAS-ELISA. RT-PCR, with the specific primer for WMV-cp. gene, yielded 825 base pair DNA fragments. The results that belong to soluble protein analysis indicated that infected hypocotyl explants treated with 6 g L(-1) recorded the highest rate in the number of soluble protein bands compared with the rest of treatments. As a conclusion of these results, we can recommend to apply the Thuja extract at 6 g L(-1) as a optimum dosage to decrease the infection caused by watermelon mosaic potyvirus.

  2. Gene expression profiling of peach fruit during stone development

    USDA-ARS?s Scientific Manuscript database

    The availability of seedless grapes and watermelons has energized these fruit markets and resulted in increased consumption. Seedless stone fruits including peaches, plums, and cherries would undoubtedly have similar positive impacts on these industries. However, this would require the elimination...

  3. Coexistence analysis of diploid and triploid hybrid water frogs

    NASA Astrophysics Data System (ADS)

    Apri, M.; Suandi, D.; Soewono, E.

    2014-02-01

    A dynamical model for genotype distributions of all hybrid populations of Pelophylax esculentus in the absence of differential survival is studied here. Assuming that under natural condition the parental genotypes LL and RR do not survive into adult stage, the dynamic is then reduced into three-dimensional dynamical system of classes LR, LLR, LRR genotypes. Coexistence of diploid (LR) and triploid (LLR and LRR) genotypes is analyzed here.

  4. The Diploid Genome Sequence of an Individual Human

    PubMed Central

    Levy, Samuel; Sutton, Granger; Ng, Pauline C; Feuk, Lars; Halpern, Aaron L; Walenz, Brian P; Axelrod, Nelson; Huang, Jiaqi; Kirkness, Ewen F; Denisov, Gennady; Lin, Yuan; MacDonald, Jeffrey R; Pang, Andy Wing Chun; Shago, Mary; Stockwell, Timothy B; Tsiamouri, Alexia; Bafna, Vineet; Bansal, Vikas; Kravitz, Saul A; Busam, Dana A; Beeson, Karen Y; McIntosh, Tina C; Remington, Karin A; Abril, Josep F; Gill, John; Borman, Jon; Rogers, Yu-Hui; Frazier, Marvin E; Scherer, Stephen W; Strausberg, Robert L; Venter, J. Craig

    2007-01-01

    Presented here is a genome sequence of an individual human. It was produced from ∼32 million random DNA fragments, sequenced by Sanger dideoxy technology and assembled into 4,528 scaffolds, comprising 2,810 million bases (Mb) of contiguous sequence with approximately 7.5-fold coverage for any given region. We developed a modified version of the Celera assembler to facilitate the identification and comparison of alternate alleles within this individual diploid genome. Comparison of this genome and the National Center for Biotechnology Information human reference assembly revealed more than 4.1 million DNA variants, encompassing 12.3 Mb. These variants (of which 1,288,319 were novel) included 3,213,401 single nucleotide polymorphisms (SNPs), 53,823 block substitutions (2–206 bp), 292,102 heterozygous insertion/deletion events (indels)(1–571 bp), 559,473 homozygous indels (1–82,711 bp), 90 inversions, as well as numerous segmental duplications and copy number variation regions. Non-SNP DNA variation accounts for 22% of all events identified in the donor, however they involve 74% of all variant bases. This suggests an important role for non-SNP genetic alterations in defining the diploid genome structure. Moreover, 44% of genes were heterozygous for one or more variants. Using a novel haplotype assembly strategy, we were able to span 1.5 Gb of genome sequence in segments >200 kb, providing further precision to the diploid nature of the genome. These data depict a definitive molecular portrait of a diploid human genome that provides a starting point for future genome comparisons and enables an era of individualized genomic information. PMID:17803354

  5. [Diploid/triploid mosaicism: a variable but characteristic phenotype].

    PubMed

    Natera-De Benito, Daniel; Poo, Pilar; Gean, Esther; Vicente-Villa, Asunción; García-Cazorla, Angels; Fons-Estupiña, M Carmen

    2014-08-16

    Introduccion. El mosaicismo diploide/triploide es una alteracion cromosomica poco frecuente. La produce un fallo en la division poscigotica durante el desarrollo embrionario. Da lugar a la coexistencia de dos lineas celulares con diferente constitucion cromosomica (46,XX y 69,XXX) en un mismo individuo. Su fenotipo clinico es caracteristico. Las alteraciones pigmentarias con un patron de distribucion que sigue las lineas de Blaschko son el principal signo guia, asi como las alteraciones de otros tejidos derivados del ectodermo. Casos clinicos. Describimos las caracteristicas clinicas de tres pacientes afectos de mosaicismo diploide/triploide y realizamos una comparacion de su fenotipo clinico con el de los casos publicados previamente en la bibliografia. Las alteraciones observadas con mayor frecuencia fueron alteraciones cutaneas, discapacidad intelectual, obesidad troncular, talla baja, hemihipertrofia, y manos pequeñas y estrechas con clino y camptodactilia. Las caracteristicas fenotipicas de nuestros pacientes fueron similares a las de los casos comunicados previamente. Aunque no existe un fenotipo unico y especifico asociado al mosaicismo diploide/triploide, existen malformaciones caracteristicas que conforman un sindrome malformativo bien definido. El cariotipo realizado en linfocitos de sangre periferica en las tres pacientes fue normal, y se logro el diagnostico mediante cariotipo en fibroblastos cultivados tras biopsia de piel hipopigmentada. Conclusiones. La presencia de discapacidad intelectual asociada a obesidad troncular, talla baja, hemihipertrofia o clino y camptodactilia, ademas de las alteraciones cutaneas, debe hacer pensar en la posible existencia de un mosaicismo diploide/triploide. En la mayoria de los casos, es necesario el estudio del cariotipo en los fibroblastos para llegar al diagnostico.

  6. The diploid genome sequence of an individual human.

    PubMed

    Levy, Samuel; Sutton, Granger; Ng, Pauline C; Feuk, Lars; Halpern, Aaron L; Walenz, Brian P; Axelrod, Nelson; Huang, Jiaqi; Kirkness, Ewen F; Denisov, Gennady; Lin, Yuan; MacDonald, Jeffrey R; Pang, Andy Wing Chun; Shago, Mary; Stockwell, Timothy B; Tsiamouri, Alexia; Bafna, Vineet; Bansal, Vikas; Kravitz, Saul A; Busam, Dana A; Beeson, Karen Y; McIntosh, Tina C; Remington, Karin A; Abril, Josep F; Gill, John; Borman, Jon; Rogers, Yu-Hui; Frazier, Marvin E; Scherer, Stephen W; Strausberg, Robert L; Venter, J Craig

    2007-09-04

    Presented here is a genome sequence of an individual human. It was produced from approximately 32 million random DNA fragments, sequenced by Sanger dideoxy technology and assembled into 4,528 scaffolds, comprising 2,810 million bases (Mb) of contiguous sequence with approximately 7.5-fold coverage for any given region. We developed a modified version of the Celera assembler to facilitate the identification and comparison of alternate alleles within this individual diploid genome. Comparison of this genome and the National Center for Biotechnology Information human reference assembly revealed more than 4.1 million DNA variants, encompassing 12.3 Mb. These variants (of which 1,288,319 were novel) included 3,213,401 single nucleotide polymorphisms (SNPs), 53,823 block substitutions (2-206 bp), 292,102 heterozygous insertion/deletion events (indels)(1-571 bp), 559,473 homozygous indels (1-82,711 bp), 90 inversions, as well as numerous segmental duplications and copy number variation regions. Non-SNP DNA variation accounts for 22% of all events identified in the donor, however they involve 74% of all variant bases. This suggests an important role for non-SNP genetic alterations in defining the diploid genome structure. Moreover, 44% of genes were heterozygous for one or more variants. Using a novel haplotype assembly strategy, we were able to span 1.5 Gb of genome sequence in segments >200 kb, providing further precision to the diploid nature of the genome. These data depict a definitive molecular portrait of a diploid human genome that provides a starting point for future genome comparisons and enables an era of individualized genomic information.

  7. NMR Spectroscopy Identifies Metabolites Translocated from Powdery Mildew Resistant Rootstocks to Susceptible Watermelon Scions.

    PubMed

    Mahmud, Iqbal; Kousik, Chandrasekar; Hassell, Richard; Chowdhury, Kamal; Boroujerdi, Arezue F

    2015-09-16

    Powdery mildew (PM) disease causes significant loss in watermelon. Due to the unavailability of a commercial watermelon variety that is resistant to PM, grafting susceptible cultivars on wild resistant rootstocks is being explored as a short-term management strategy to combat this disease. Nuclear magnetic resonance-based metabolic profiles of susceptible and resistant rootstocks of watermelon and their corresponding susceptible scions (Mickey Lee) were compared to screen for potential metabolites related to PM resistance using multivariate principal component analysis. Significant score plot differences between the susceptible and resistant groups were revealed through Mahalanobis distance analysis. Significantly different spectral buckets and their corresponding metabolites (including choline, fumarate, 5-hydroxyindole-3-acetate, and melatonin) have been identified quantitatively using multivariate loading plots and verified by volcano plot analyses. The data suggest that these metabolites were translocated from the powdery mildew resistant rootstocks to their corresponding powdery mildew susceptible scions and can be related to PM disease resistance.

  8. Quantitative Understanding of Nanoparticle Uptake in Watermelon Plants

    PubMed Central

    Raliya, Ramesh; Franke, Christina; Chavalmane, Sanmathi; Nair, Remya; Reed, Nathan; Biswas, Pratim

    2016-01-01

    The use of agrochemical-nutrient fertilizers has come under scrutiny in recent years due to concerns that they damage the ecosystem and endanger public health. Nanotechnology offers many possible interventions to mitigate these risks by use of nanofertilizers, nanopesticides, and nanosensors; and concurrently increases profitability, yields, and sustainability within the agricultural industry. Aerosol based foliar delivery of nanoparticles may help to enhance nanoparticle uptake and reduce environmental impacts of chemical fertilizers conventionally applied through a soil route. The purpose of this work was to study uptake, translocation, and accumulation of various gold nanostructures, 30–80 nm, delivered by aerosol application to a watermelon plant. Cellular uptake and accumulation of gold nanoparticles were quantified by Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS). Observations suggested that nanoparticles could be taken up by the plant through direct penetration and transport through the stomatal opening. Observed translocation of nanoparticles from leaf to root shows evidence that nanoparticles travel by the phloem transport mechanism. Accumulation and transport of nanoparticles depend on nanoparticle shape, application method, and nature of plant tissues. PMID:27617020

  9. Extensive Recombination of a Yeast Diploid Hybrid through Meiotic Reversion

    PubMed Central

    Laureau, Raphaëlle; Loeillet, Sophie; Salinas, Francisco; Bergström, Anders; Legoix-Né, Patricia; Liti, Gianni; Nicolas, Alain

    2016-01-01

    In somatic cells, recombination between the homologous chromosomes followed by equational segregation leads to loss of heterozygosity events (LOH), allowing the expression of recessive alleles and the production of novel allele combinations that are potentially beneficial upon Darwinian selection. However, inter-homolog recombination in somatic cells is rare, thus reducing potential genetic variation. Here, we explored the property of S. cerevisiae to enter the meiotic developmental program, induce meiotic Spo11-dependent double-strand breaks genome-wide and return to mitotic growth, a process known as Return To Growth (RTG). Whole genome sequencing of 36 RTG strains derived from the hybrid S288c/SK1 diploid strain demonstrates that the RTGs are bona fide diploids with mosaic recombined genome, derived from either parental origin. Individual RTG genome-wide genotypes are comprised of 5 to 87 homozygous regions due to the loss of heterozygous (LOH) events of various lengths, varying between a few nucleotides up to several hundred kilobases. Furthermore, we show that reiteration of the RTG process shows incremental increases of homozygosity. Phenotype/genotype analysis of the RTG strains for the auxotrophic and arsenate resistance traits validates the potential of this procedure of genome diversification to rapidly map complex traits loci (QTLs) in diploid strains without undergoing sexual reproduction. PMID:26828862

  10. Insulin stimulation of glycogen synthase in cultured human diploid fibroblasts.

    PubMed

    Hidaka, H; Howard, B V; Kosmakos, F C; Fields, R M; Craig, J W; Bennett, P H; Larner, J

    1980-10-01

    The effect of insulin on glycogen synthase activity in human diploid fibroblasts has been studied. As little as 2 X 10(-10) M insulin increased the glycogen synthase / activity without changing the total activity. Stimulation occurred within 5 min and became maximal in 30 min. A half-maximal increase of / activity was achieved at 3 X 10(-9) M insulin. Glucose starvation increased the magnitude of response of glycogen synthase to insulin but did not change the insulin concentration necessary to give a half-maximal stimulation. Glucose increased the basal level of / activity in human diploid fibroblasts; the effect of insulin was additive. During in vitro senescence the total glycogen synthase activity declined, but the concentration of insulin that produced a half-maximal stimulation remained unchanged. These data indicate that regulation of glycogen synthase activity in human diploid fibroblasts is responsive to physiologic insulin levels and that the system provides a useful model for the in vitro study of insulin sensitivity.

  11. Reference genes for normalizing transcription in diploid and tetraploid Arabidopsis.

    PubMed

    Wang, Haibin; Wang, Jingjing; Jiang, Jiafu; Chen, Sumei; Guan, Zhiyong; Liao, Yuan; Chen, Fadi

    2014-10-27

    Published transcription data from a set of 19 diploid Arabidopsis thaliana and 5 tetraploid (3 allo- and 2 auto- tetraploid) Arabidopsis accessions were re-analysed to identify reliable reference genes for normalization purposes. Five conventional and 16 novel reference genes previously derived from microarray data covering a wide range of abundance in absolute expression levels in diploid A. thaliana Col-0 were employed. Transcript abundance was well conserved for all 21 potential reference genes in the diploid A. thaliana accessions, with geNorm and NormFinder analysis indicating that AT5G46630, AT1G13320, AT4G26410, AT5G60390 and AT5G08290 were the most stable. However, conservation was less good among the tetraploid accessions, with the transcription of seven of the 21 genes being undetectable in all allotetraploids. The most stable gene was AT5G46630, while AT1G13440 was the unstable one. Hence, the choice of reference gene(s) for A. thaliana is quite wide, but with respect to the analysis of transcriptomic data derived from the tetraploids, it is probably necessary to select more than one reference gene.

  12. Genetic Analysis of Isozyme Variants in Diploid and Tetraploid Potatoes

    PubMed Central

    Quiros, Carlos F.; McHale, Neil

    1985-01-01

    Genetic segregations for six enzyme-coding genes were studied in diploid and tetraploid progenies obtained from various Solanum species. The loci identified are Prx-2, Prx-3, Prx-5, Mdh-1, Pgi-1 and Sdh-1. Prx-2 and Prx-3 were found to be linked; alleles at these loci segregated concomitantly in most of the diploid progenies. The putative homologous loci in tomato, Prx-2 and Prx-3, have also been reported to be linked, suggesting that this linkage block has been conserved since the divergence of Solanum and Lycopersicon. Several interspecific crosses between the species S. phureja and S. tuberosum, S. phureja and S. chacoense, and S. tuberosum and S. chacoense, yielded segregations for Prx-2 that deviated from expected Mendelian ratios. In these progenies unexpected phenotypes were commonly found, most likely due to posttranscriptional modification. Products of some of the alleles of Mdh-1 probably suffered posttranscriptional modifications, although most of their segregations fitted expected Mendelian ratios. The most extreme case of posttranscriptional modification was found in phenotypes involving allele Mdh-14. Instead of the expected heterodimers in the heterozygous individuals, a slowly migrating band close to the origin was observed in these phenotypes. Some of the accessions of the diploid species S. sparsipilum were found to have a unique zymogram for a second MDH zone of electrophoretic activity, MDH-2. We propose in this paper a common nomenclature for potato isozymes based on the nomenclature used for Capsicum and Lycopersicon. PMID:17246296

  13. Simple sequence repeat diversity in diploid and tetraploid Coffea species.

    PubMed

    Moncada, Pilar; McCouch, Susan

    2004-06-01

    Thirty-four fluorescently labeled microsatellite markers were used to assess genetic diversity in a set of 30 Coffea accessions from the CENICAFE germplasm bank in Colombia. The plant material included one sample per accession of seven East African accessions representing five diploid species and 23 wild and cultivated tetraploid accessions of Coffea arabica from Africa, Indonesia, and South America. More allelic diversity was detected among the five diploid species than among the 23 tetraploid genotypes. The diploid species averaged 3.6 alleles/locus and had an average polymorphism information content (PIC) value of 0.6, whereas the wild tetraploids averaged 2.5 alleles/locus and had an average PIC value of 0.3 and the cultivated tetraploids (C. arabica cultivars) averaged 1.9 alleles/locus and had an average PIC value of 0.22. Fifty-five percent of the alleles found in the wild tetraploids were not shared with cultivated C. arabica genotypes, supporting the idea that the wild tetraploid ancestors from Ethiopia could be used productively as a source of novel genetic variation to expand the gene pool of elite C. arabica germplasm.

  14. Sexual conflict and the alternation of haploid and diploid generations

    PubMed Central

    Haig, David; Wilczek, Amity

    2006-01-01

    Land plants possess a multicellular diploid stage (sporophyte) that begins development while attached to a multicellular haploid progenitor (gametophyte). Although the closest algal relatives of land plants lack a multicellular sporophyte, they do produce a zygote that grows while attached to the maternal gametophyte. The diploid offspring shares one haploid set of genes with the haploid mother that supplies it with resources and a paternal haploid complement that is not shared with the mother. Sexual conflict can arise within the diploid offspring because the offspring's maternal genome will be transmitted in its entirety to all other sexual and asexual offspring that the mother may produce, but the offspring's paternally derived genes may be absent from these other offspring. Thus, the selective forces favouring the evolution of genomic imprinting may have been present from the origin of modern land plants. In bryophytes, where gametophytes are long-lived and capable of multiple bouts of asexual and sexual reproduction, we predict strong sexual conflict over allocation to sporophytes. Female gametophytes of pteridophytes produce a single sporophyte and often lack means of asexual reproduction. Therefore, sexual conflict is predicted to be attenuated. Finally, we explore similarities among models of mate choice, offspring choice and segregation distortion. PMID:16612891

  15. The metacaspase gene family of Vitis vinifera L.: characterization and differential expression during ovule abortion in stenospermocarpic seedless grapes.

    PubMed

    Zhang, Chaohong; Gong, Peijie; Wei, Rong; Li, Shuxiu; Zhang, Xutong; Yu, Yihe; Wang, Yuejin

    2013-10-10

    In both plants and animals, programmed cell death (PCD) is an indispensable process that removes redundant cells. In seedless grapes (Vitis vinifera), abnormal PCD in ovule cells and subsequent ovule abortion play key roles in stenospermocarpy. Metacaspase, a type of cysteine-dependent protease, plays an essential role in PCD. To reveal the characteristics of the metacaspase (MC) gene family and the relationship between metacaspases and the seedless trait, we identified the 6 V. vinifera metacaspases VvMC1-VvMC6, from the grape genome, using BLASTN against the 9 known Arabidopsis metacaspases. We also obtained full-length cDNAs by RT-PCR. Each of the 6 grape metacaspases contains small (p10-like) and a large (p20-like) conserved structural domains. Phylogenetic analysis of 6 grape and 9 Arabidopsis metacaspases showed that all metacaspases could be grouped into two classes: Type I and Type II. Each phylogenetic branch shares a similar exon/intron structure. Furthermore, the putative promoters of the grape metacaspases contained cis-elements that are involved in grape endosperm development. Moreover, expression analysis of metacaspases using real-time quantitative PCR demonstrated that VvMC1 and VvMC2 were able to be detected in any tissue, and VvMC3, VvMC4, VvMC5 and VvMC6 exhibited tissue-specific expression. Lastly, in cv. Thompson seedless grapes VvMC1, VvMC3, and VvMC4 were significantly up-regulated at the 35 DAF during ovule development, roughly same stage as endosperm abortion. In addition, the expression trend of VvMC2 and VvMC5 was similar between cv. Pinot Noir and cv. Thompson grape ovule development and that of VvMC6 was sustained in a relatively low level except the expression of cv. Pinot Noir significantly up-regulated in 25 DAF. Our data provided new insights into PCD by identifying the grape metacaspase gene family and provide a useful reference for further functional analysis of metacaspases in grape. © 2013.

  16. Extraction conditions affecting supercritical fluid extraction (SFE) of lycopene from watermelon.

    PubMed

    Katherine, L S Vaughn; Edgar, C Clausen; Jerry, W King; Luke, R Howard; Julie, Carrier Danielle

    2008-11-01

    Lycopene, a carotenoid linked to protection against certain forms of cancer, is found in produce such as papaya, red-fleshed tomatoes, grapefruit and watermelon. The preparation of a supercritical CO2 (SC-CO2) watermelon-lycopene extract could serve as a food grade source of this carotenoid. This study established preliminary conditions for enhancing SC-CO2 extraction of lycopene from watermelon. Freeze-dried watermelon was extracted with SC-CO2 and ethanol as an organic co-solvent. The lycopene concentration was determined by HPLC, with absorbance measured at 503 nm. In an initial set of experiments, the effects of extraction temperature (70-90 degrees C), pressure (20.7-41.4 MPa) and co-solvent ethanol addition (10-15%) were evaluated. A lycopene yield of 38 microg per gram of wet weight was obtained at 70 degrees C, 20.7 MPa, and 15% by volume ethanol. The extraction of fresh (non-freeze-dried) watermelon yielded 103+/-6 microg lycopene per gram fresh fruit weight. Of the parameters tested, temperature had the most effect on lycopene yield. Thus, in another set of experiments, the temperature was varied from 60-75 degrees C at an extraction pressure of 20.7 MPa in the presence of 15% ethanol. Studies showed that freeze-dried watermelon flesh loses lycopene in storage. In accounting for lycopene storage losses, lycopene yields at 60 degrees C extraction temperature were 14% greater than those obtained at 70 degrees C.

  17. Resistance to Southern Root-knot Nematode (Meloidogyne incognita) in Wild Watermelon (Citrullus lanatus var. citroides).

    PubMed

    Thies, Judy A; Ariss, Jennifer J; Kousik, Chandrasekar S; Hassell, Richard L; Levi, Amnon

    2016-03-01

    Southern root-knot nematode (RKN, Meloidogyne incognita) is a serious pest of cultivated watermelon (Citrullus lanatus var. lanatus) in southern regions of the United States and no resistance is known to exist in commercial watermelon cultivars. Wild watermelon relatives (Citrullus lanatus var. citroides) have been shown in greenhouse studies to possess varying degrees of resistance to RKN species. Experiments were conducted over 2 yr to assess resistance of southern RKN in C. lanatus var. citroides accessions from the U.S. Watermelon Plant Introduction Collection in an artificially infested field site at the U.S. Vegetable Laboratory in Charleston, SC. In the first study (2006), 19 accessions of C. lanatus var. citroides were compared with reference entries of Citrullus colocynthis and C. lanatus var. lanatus. Of the wild watermelon accessions, two entries exhibited significantly less galling than all other entries. Five of the best performing C. lanatus var. citroides accessions were evaluated with and without nematicide at the same field site in 2007. Citrullus lanatus var. citroides accessions performed better than C. lanatus var. lanatus and C. colocynthis. Overall, most entries of C. lanatus var. citroides performed similarly with and without nematicide treatment in regard to root galling, visible egg masses, vine vigor, and root mass. In both years of field evaluations, most C. lanatus var. citroides accessions showed lesser degrees of nematode reproduction and higher vigor and root mass than C. colocynthis and C. lanatus var. lanatus. The results of these two field evaluations suggest that wild watermelon populations may be useful sources of resistance to southern RKN.

  18. Genetic diversity in watermelon (Citrullus lanatus) landraces from Zimbabwe revealed by RAPD and SSR markers.

    PubMed

    Mujaju, C; Sehic, J; Werlemark, G; Garkava-Gustavsson, L; Fatih, M; Nybom, H

    2010-08-01

    Low polymorphism in cultivated watermelon has been reported in previous studies, based mainly on US Plant Introductions and watermelon cultivars, most of which were linked to breeding programmes associated with disease resistance. Since germplasm sampled in a putative centre of origin in southern Africa may harbour considerably higher variability, DNA marker-based diversity was estimated among 81 seedlings from eight accessions of watermelon collected in Zimbabwe; five accessions of cow-melons (Citrullus lanatus var. citroides) and three of sweet watermelons (C. lanatus var. lanatus). Two molecular marker methods were used, random amplified polymorphic DNA (RAPD) and simple sequence repeats (SSR) also known as microsatellite DNA. Ten RAPD primers produced 138 markers of which 122 were polymorphic. Nine SSR primer pairs detected a total of 43 alleles with an average of 4.8 alleles per locus. The polymorphic information content (PIC) ranged from 0.47 to 0.77 for the RAPD primers and from 0.39 to 0.97 for the SSR loci. Similarity matrices obtained with SSR and RAPD, respectively, were highly correlated but only RAPD was able to provide each sample with an individual-specific DNA profile. Dendrograms and multidimensional scaling (MDS) produced two major clusters; one with the five cow-melon accessions and the other with the three sweet watermelon accessions. One of the most variable cow-melon accessions took an intermediate position in the MDS analysis, indicating the occurrence of gene flow between the two subspecies. Analysis of molecular variation (AMOVA) attributed most of the variability to within-accessions, and contrary to previous reports, sweet watermelon accessions apparently contain diversity of the same magnitude as the cow-melons.

  19. Resistance to Southern Root-knot Nematode (Meloidogyne incognita) in Wild Watermelon (Citrullus lanatus var. citroides)

    PubMed Central

    Thies, Judy A.; Ariss, Jennifer J.; Kousik, Chandrasekar S.; Hassell, Richard L.; Levi, Amnon

    2016-01-01

    Southern root-knot nematode (RKN, Meloidogyne incognita) is a serious pest of cultivated watermelon (Citrullus lanatus var. lanatus) in southern regions of the United States and no resistance is known to exist in commercial watermelon cultivars. Wild watermelon relatives (Citrullus lanatus var. citroides) have been shown in greenhouse studies to possess varying degrees of resistance to RKN species. Experiments were conducted over 2 yr to assess resistance of southern RKN in C. lanatus var. citroides accessions from the U.S. Watermelon Plant Introduction Collection in an artificially infested field site at the U.S. Vegetable Laboratory in Charleston, SC. In the first study (2006), 19 accessions of C. lanatus var. citroides were compared with reference entries of Citrullus colocynthis and C. lanatus var. lanatus. Of the wild watermelon accessions, two entries exhibited significantly less galling than all other entries. Five of the best performing C. lanatus var. citroides accessions were evaluated with and without nematicide at the same field site in 2007. Citrullus lanatus var. citroides accessions performed better than C. lanatus var. lanatus and C. colocynthis. Overall, most entries of C. lanatus var. citroides performed similarly with and without nematicide treatment in regard to root galling, visible egg masses, vine vigor, and root mass. In both years of field evaluations, most C. lanatus var. citroides accessions showed lesser degrees of nematode reproduction and higher vigor and root mass than C. colocynthis and C. lanatus var. lanatus. The results of these two field evaluations suggest that wild watermelon populations may be useful sources of resistance to southern RKN. PMID:27168648

  20. Genome-wide identification and comparative expression analysis of LEA genes in watermelon and melon genomes.

    PubMed

    Celik Altunoglu, Yasemin; Baloglu, Mehmet Cengiz; Baloglu, Pinar; Yer, Esra Nurten; Kara, Sibel

    2017-01-01

    Late embryogenesis abundant (LEA) proteins are large and diverse group of polypeptides which were first identified during seed dehydration and then in vegetative plant tissues during different stress responses. Now, gene family members of LEA proteins have been detected in various organisms. However, there is no report for this protein family in watermelon and melon until this study. A total of 73 LEA genes from watermelon (ClLEA) and 61 LEA genes from melon (CmLEA) were identified in this comprehensive study. They were classified into four and three distinct clusters in watermelon and melon, respectively. There was a correlation between gene structure and motif composition among each LEA groups. Segmental duplication played an important role for LEA gene expansion in watermelon. Maximum gene ontology of LEA genes was observed with poplar LEA genes. For evaluation of tissue specific expression patterns of ClLEA and CmLEA genes, publicly available RNA-seq data were analyzed. The expression analysis of selected LEA genes in root and leaf tissues of drought-stressed watermelon and melon were examined using qRT-PCR. Among them, ClLEA-12-17-46 genes were quickly induced after drought application. Therefore, they might be considered as early response genes for water limitation conditions in watermelon. In addition, CmLEA-42-43 genes were found to be up-regulated in both tissues of melon under drought stress. Our results can open up new frontiers about understanding of functions of these important family members under normal developmental stages and stress conditions by bioinformatics and transcriptomic approaches.

  1. Application of magnetic resonance imaging to non-destructive void detection in watermelon

    NASA Astrophysics Data System (ADS)

    Saito, K.; Miki, T.; Hayashi, S.; Kajikawa, H.; Shimada, M.; Kawate, Y.; Nishizawa, T.; Ikegaya, D.; Kimura, N.; Takabatake, K.; Sugiura, N.; Suzuki, M.

    A novel application of magnetic resonance imaging (MRI) is described. The possibility of utilizing MRI for non-destructive quality evaluation of watermelons was studied. In this study, we applied MRI to the detection of internal voids in watermelons. In order to increase the measurement rate, we employed a one-dimensional projection profile method instead of observing a two-dimensional cross-sectional image. The void detection was carried out with this technique over 30 samples and 28 samples were correctly evaluated. The measurement rate was 900 ms per sample, which is an acceptable speed for a sorting machine in the agricultural field.

  2. Algerian watermelon mosaic virus (AWMV): a new potyvirus species in the PRSV cluster.

    PubMed

    Yakoubi, Soumaya; Lecoq, Hervé; Desbiez, Cécile

    2008-08-01

    A potyvirus was isolated from a naturally infected squash plant in Algeria in 1986. Biological and serological data have revealed that the virus, initially described as H4, is related to other cucurbit-infecting potyviruses, particularly Moroccan watermelon mosaic virus (MWMV) and Papaya ringspot virus (PRSV). To establish unequivocally the taxonomic status of H4, its full-length genome sequence was established. H4 shared identities of 70% and 65% at the amino acid level with MWMV and PRSV, respectively, indicating that H4 is a distinct species of the PRSV cluster. The name Algerian watermelon mosaic virus (AWMV) is proposed for this new potyvirus species.

  3. [Sugar characterization of mini-watermelon and rapid sugar determination by near infrared diffuse reflectance spectroscopy].

    PubMed

    Wang, Shuo; Yuan, Hong-fu; Song, Chun-feng; Xie, Jin-chun; Li, Xiao-yu; Feng, Le-ping

    2012-08-01

    In the present paper, the distribution of sugar level within the mini-watermelon was studied, a new sugar characterization method of mini-watermelon using average sugar level, the highest sugar level and the lowest sugar level index is proposed. Feasibility of nondestructive determination of mini-watermenlon sugar level using diffuse reflectance spectroscopy information was investigated by an experiment. PLS models for measuring the 3 sugar levels were established. The results obtained by near infrared spectroscopy agreed with that of the new method established above.

  4. Analysis of variation for apomictic reproduction in diploid Paspalum rufum

    PubMed Central

    Delgado, Luciana; Galdeano, Florencia; Sartor, María E.; Quarin, Camilo L.; Espinoza, Francisco; Ortiz, Juan Pablo A.

    2014-01-01

    Background and Aims The diploid cytotype of Paspalum rufum (Poaceae) reproduces sexually and is self-sterile; however, recurrent autopolyploidization through 2n + n fertilization and the ability for reproduction via apomixis have been documented in one genotype of the species. The objectives of this work were to analyse the variation in the functionality of apomixis components in diploid genotypes of P. rufum and to identify individuals with contrasting reproductive behaviours. Methods Samples of five individuals from each of three natural populations of P. rufum (designated R2, R5 and R6) were used. Seeds were obtained after open pollination, selfing, conspecific interploidy crosses and interspecific interploidy self-pollination induction. The reproductive behaviour of each plant was determined by using the flow cytometric seed screen (FCSS) method. Embryo sacs were cleared using a series of ethanol and methyl salicylate solutions and observed microscopically. Key Results In open pollination, all genotypes formed seeds by sexual means and no evidence of apomeiotic reproduction was detected. However, in conspecific interploidy crosses and interspecific interploidy self-pollination induction, variations in the reproductive pathways were observed. While all plants from populations R2 and R6 formed seeds exclusively by sexual means, three genotypes from the R5 population developed seeds from both meiotic and aposporous embryo sacs, and one of them (R5#49) through the complete apomictic pathway (apospory + parthenogenesis + pseudogamy). Cytoembryological observations revealed the presence of both meiotic and aposporous embryo sacs in all the genotypes analysed, suggesting that parthenogenesis could be uncoupled from apospory in some genotypes. Conclusions The results presented demonstrate the existence of variation in the functionality of apomixis components in natural diploid genotypes of P. rufum and have identified individuals with contrasting reproductive

  5. Analysis of variation for apomictic reproduction in diploid Paspalum rufum.

    PubMed

    Delgado, Luciana; Galdeano, Florencia; Sartor, María E; Quarin, Camilo L; Espinoza, Francisco; Ortiz, Juan Pablo A

    2014-06-01

    The diploid cytotype of Paspalum rufum (Poaceae) reproduces sexually and is self-sterile; however, recurrent autopolyploidization through 2n + n fertilization and the ability for reproduction via apomixis have been documented in one genotype of the species. The objectives of this work were to analyse the variation in the functionality of apomixis components in diploid genotypes of P. rufum and to identify individuals with contrasting reproductive behaviours. Samples of five individuals from each of three natural populations of P. rufum (designated R2, R5 and R6) were used. Seeds were obtained after open pollination, selfing, conspecific interploidy crosses and interspecific interploidy self-pollination induction. The reproductive behaviour of each plant was determined by using the flow cytometric seed screen (FCSS) method. Embryo sacs were cleared using a series of ethanol and methyl salicylate solutions and observed microscopically. In open pollination, all genotypes formed seeds by sexual means and no evidence of apomeiotic reproduction was detected. However, in conspecific interploidy crosses and interspecific interploidy self-pollination induction, variations in the reproductive pathways were observed. While all plants from populations R2 and R6 formed seeds exclusively by sexual means, three genotypes from the R5 population developed seeds from both meiotic and aposporous embryo sacs, and one of them (R5#49) through the complete apomictic pathway (apospory + parthenogenesis + pseudogamy). Cytoembryological observations revealed the presence of both meiotic and aposporous embryo sacs in all the genotypes analysed, suggesting that parthenogenesis could be uncoupled from apospory in some genotypes. The results presented demonstrate the existence of variation in the functionality of apomixis components in natural diploid genotypes of P. rufum and have identified individuals with contrasting reproductive behaviours. Genotypes identified here can be crossed to

  6. Characters that differ between diploid and haploid honey bee (Apis mellifera) drones.

    PubMed

    Herrmann, Matthias; Trenzcek, Tina; Fahrenhorst, Hartmut; Engels, Wolf

    2005-12-30

    Diploid males have long been considered a curiosity contradictory to the haplo-diploid mode of sex determination in the Hymenoptera. In Apis mellifera, 'false' diploid male larvae are eliminated by worker cannibalism immediately after hatching. A 'cannibalism substance' produced by diploid drone larvae to induce worker-assisted suicide has been hypothesized, but it has never been detected. Diploid drones are only removed some hours after hatching. Older larvae are evidently not regarded as 'false males' and instead are regularly nursed by the brood-attending worker bees. As the pheromonal cues presumably are located on the surface of newly hatched bee larvae, we extracted the cuticular secretions and analyzed their chemical composition by gas chromatograph-mass spectrometry (GC-MS) analyses. Larvae were sexed and then reared in vitro for up to three days. The GC-MS pattern that was obtained, with alkanes as the major compounds, was compared between diploid and haploid drone larvae. We also examined some physical parameters of adult drones. There was no difference between diploid and haploid males in their weight at the day of emergence. The diploid adult drones had fewer wing hooks and smaller testes. The sperm DNA content was 0.30 and 0.15 pg per nucleus, giving an exact 2:1 ratio for the gametocytes of diploid and haploid drones, respectively. Vitellogenin was found in the hemolymph of both types of imaginal drones at 5 to 6 days, with a significantly lower titer in the diploids.

  7. Diploid Male Production Results in Queen Death in the Stingless Bee Scaptotrigona depilis.

    PubMed

    Vollet-Neto, Ayrton; Oliveira, Ricardo C; Schillewaert, Sharon; Alves, Denise A; Wenseleers, Tom; Nascimento, Fabio S; Imperatriz-Fonseca, Vera L; Ratnieks, Francis L W

    2017-04-06

    As in most Hymenoptera, the eusocial stingless bees (Meliponini) have a complementary sex determination (CSD) system. When a queen makes a "matched mating" with a male that shares a CSD allele with her, half of their diploid offspring are diploid males rather than females. Matched mating imposes a cost, since diploid male production reduces the colony workforce. Hence, adaptations preventing the occurrence or attenuating its effects are likely to arise. Here we provide clear evidence that in the stingless bee Scaptotrigona depilis, the emergence of diploid males induces queen death, and this usually occurs within 10-20 days of the emergence of diploid male offspring from their pupae. Queens that have not made a matched mating die when introduced into a colony in which diploid males are emerging. This shows that the adult diploid males, and not the queen that has made a matched mating herself, are the proximate cause of queen death. Analysis of the cuticular hydrocarbon profiles of adult haploid and diploid males shows six compounds with significant differences. Moreover, the diploid and haploid males only acquire distinct cuticular hydrocarbon profiles 10 days after emergence. Our data shows that the timing of queen death occurs when the cuticular hydrocarbons of haploid and diploid males differ significantly, suggesting that these chemical differences could be used as cues or signals to trigger queen death.

  8. Optimization of antireflective zinc oxide nanorod arrays on seedless substrate for bulk-heterojunction organic solar cells

    NASA Astrophysics Data System (ADS)

    Woo Choi, Hyung; Lee, Kyu-Sung; Alford, T. L.

    2012-10-01

    We report on the enhanced performance of hybrid photovoltaic devices consisting of poly(3-hexylthiophene), (6,6)-phenyl C61 butyric acid methyl ester, and zinc oxide (ZnO) nanorod arrays grown on seedless indium tin oxide (ITO) glass in aqueous zinc chloride solution. Introduction of optimized-length ZnO nanorod arrays between hole injection and ITO layers increased photocurrent density from 8.0 to 8.8 mA/cm2 and fill factor from 42% to 47%. The absence of a seed layer significantly reduced incident light reflection on the ITO glass and resulted in an overall 10% increase in photocurrent. A photovoltaic device based on a ZnO nanostructure length of 100 nm exhibited a maximum power conversion efficiency of 2.4%, 15% higher than that of an equivalent device without ZnO nanorods.

  9. Seedless velocimetry at 100  kHz with picosecond-laser electronic-excitation tagging.

    PubMed

    Jiang, Naibo; Mance, Jason G; Slipchenko, Mikhail N; Felver, Josef J; Stauffer, Hans U; Yi, Tongxun; Danehy, Paul M; Roy, Sukesh

    2017-01-15

    Picosecond-laser electronic-excitation tagging (PLEET), a seedless picosecond-laser-based velocimetry technique, is demonstrated in non-reactive flows at a repetition rate of 100 kHz with a 1064 nm, 100 ps burst-mode laser. The fluorescence lifetime of the PLEET signal was measured in nitrogen, and the laser heating effects were analyzed. PLEET experiments with a free jet of nitrogen show the ability to measure multi-point flow velocity fluctuations at a 100 kHz detection rate or higher. Both spectral and dynamic mode decomposition analyses of velocity on a Ma=0.8 free jet show two dominant Strouhal numbers around 0.24 and 0.48, respectively, well within the shear-layer flapping frequencies of the free jets. This technique increases the laser-tagging repetition rate for velocimetry to hundreds of kilohertz. PLEET is suitable for subsonic through supersonic laminar- and turbulent-flow velocity measurements.

  10. Seedless Pattern Growth of Quasi-Aligned ZnO Nanorod Arrays on Cover Glass Substrates in Solution

    PubMed Central

    2010-01-01

    A hybrid technique for the selective growth of ZnO nanorod arrays on wanted areas of thin cover glass substrates was developed without the use of seed layer of ZnO. This method utilizes electron-beam lithography for pattern transfer on seedless substrate, followed by solution method for the bottom-up growth of ZnO nanorod arrays on the patterned substrates. The arrays of highly crystalline ZnO nanorods having diameter of 60 ± 10 nm and length of 750 ± 50 nm were selectively grown on different shape patterns and exhibited a remarkable uniformity in terms of diameter, length, and density. The room temperature cathodluminescence measurements showed a strong ultraviolet emission at 381 nm and broad visible emission at 585–610 nm were observed in the spectrum. PMID:20672029

  11. Transgenic plants from shoot apical meristems of Vitis vinifera L. "Thompson Seedless" via Agrobacterium-mediated transformation.

    PubMed

    Dutt, M; Li, Z T; Dhekney, S A; Gray, D J

    2007-12-01

    Shoot apical meristem explants of Vitis vinifera "Thompson Seedless" were used for Agrobacterium-mediated genetic transformation. It was determined that the meristems had to be subjected to a dark growth phase then wounded to obtain transgenic plants. Morphological and histological studies illustrated the role of wounding to expose apical meristem cells for transformation. A bifunctional egfp/nptII fusion gene was used to select kanamycin resistant plants that expressed green fluorescent protein (GFP). Kanamycin at a concentration of 16 mg L(-1) in selection medium resulted in recovery of non-chimeric transgenic plants that uniformly expressed GFP, whereas 8 mg L(-1) kanamycin allowed non-transgenic and/or chimeric plants to develop. Polymerase chain reaction (PCR) and Southern blot analyses confirmed the presence of transgenes and their stable integration into the genome of regenerated plants. Up to 1% of shoot tips produced stable transgenic cultures within 6 weeks of treatment, resulting in a total of 18 independent lines.

  12. Evolutionary and expression analysis of a MADS-box gene superfamily involved in ovule development of seeded and seedless grapevines.

    PubMed

    Wang, Li; Yin, Xiangjing; Cheng, Chenxia; Wang, Hao; Guo, Rongrong; Xu, Xiaozhao; Zhao, Jiao; Zheng, Yi; Wang, Xiping

    2015-06-01

    MADS-box transcription factors are involved in many aspects of plant growth and development, such as floral organ determination, fruit ripening, and embryonic development. Yet not much is known about grape (Vitis vinifera) MADS-box genes in a relatively comprehensive genomic and functional way during ovule development. Accordingly, we identified 54 grape MADS-box genes, aiming to enhance our understanding of grape MADS-box genes from both evolutionary and functional perspectives. Synteny analysis indicated that both segmental and tandem duplication events contributed to the expansion of the grape MADS-box family. Furthermore, synteny analysis between the grape and Arabidopsis genomes suggested that several grape MADS-box genes arose before divergence of the two species. Phylogenetic analysis and comparisons of exon-intron structures provided further insight into the evolutionary relationships between the genes, as well as their putative functions. Based on phylogenetic tree analysis, grape MADS-box genes were divided into type I and type II subgroups. Tissue-specific expression analysis suggested roles in both vegetative and reproductive tissue development. Expression analysis of the MADS-box genes following gibberellic acid (GA3) treatment revealed their response to GA3 treatment and that seedlessness caused by GA3 treatment underwent a different mechanism from that of normal ovule abortion. Expression profiling of MADS-box genes from six cultivars suggests their function in ovule development and may represent potential ovule identity genes involved in parthenocarpy. The results presented provide a few candidate genes involved in ovule development for future study, which may be useful in seedlessness-related molecular breeding programs.

  13. Cavitation Resistance in Seedless Vascular Plants: The Structure and Function of Interconduit Pit Membranes1[W][OPEN

    PubMed Central

    Brodersen, Craig; Jansen, Steven; Choat, Brendan; Rico, Christopher; Pittermann, Jarmila

    2014-01-01

    Plant water transport occurs through interconnected xylem conduits that are separated by partially digested regions in the cell wall known as pit membranes. These structures have a dual function. Their porous construction facilitates water movement between conduits while limiting the spread of air that may enter the conduits and render them dysfunctional during a drought. Pit membranes have been well studied in woody plants, but very little is known about their function in more ancient lineages such as seedless vascular plants. Here, we examine the relationships between conduit air seeding, pit hydraulic resistance, and pit anatomy in 10 species of ferns (pteridophytes) and two lycophytes. Air seeding pressures ranged from 0.8 ± 0.15 MPa (mean ± sd) in the hydric fern Athyrium filix-femina to 4.9 ± 0.94 MPa in Psilotum nudum, an epiphytic species. Notably, a positive correlation was found between conduit pit area and vulnerability to air seeding, suggesting that the rare-pit hypothesis explains air seeding in early-diverging lineages much as it does in many angiosperms. Pit area resistance was variable but averaged 54.6 MPa s m−1 across all surveyed pteridophytes. End walls contributed 52% to the overall transport resistance, similar to the 56% in angiosperm vessels and 64% in conifer tracheids. Taken together, our data imply that, irrespective of phylogenetic placement, selection acted on transport efficiency in seedless vascular plants and woody plants in equal measure by compensating for shorter conduits in tracheid-bearing plants with more permeable pit membranes. PMID:24777347

  14. The Effects of Cattle Manure and Garlic Rotation on Soil under Continuous Cropping of Watermelon (Citrullus lanatus L.)

    PubMed Central

    Liu, Changming; Wang, Yongqi; Ma, Jianxiang; Zhang, Yong; Li, Hao; Zhang, Xian

    2016-01-01

    Continuous cropping of watermelon (Citrullus lanatus L.) can lead to reduced yield and quality. We aimed to determine the effects of cattle manure addition and rotation with green garlic to improve yield and reduce disease incidence in watermelon and to examine the effects on the biological and chemical characteristics of the soil. Field experiments were performed during 2012–2014 on land previously under two years of continuous watermelon cropping in northwest China. We examined three treatment combinations: watermelon and garlic rotation, cattle manure application before watermelon planting, and combined cattle manure addition and crop rotation. Watermelon monoculture was retained as a control. Watermelon yield was significantly higher and disease incidence was lower in the treatments than the control. The populations of soil bacteria and actinomycetes and the bacteria/fungi ratio increased significantly and soil enzyme activities were generally enhanced under treatments. Available nutrients and soil organic matter contents were much higher under experimental treatments than the control. Results suggest both cattle manure application and garlic rotation can ameliorate the negative effects of continuous cropping. The combined treatment of cattle manure addition and green garlic rotation was optimal to increase yield, reduce disease incidence and enhance soil quality. PMID:27258145

  15. The Effects of Cattle Manure and Garlic Rotation on Soil under Continuous Cropping of Watermelon (Citrullus lanatus L.).

    PubMed

    Yang, Ruiping; Mo, Yanling; Liu, Changming; Wang, Yongqi; Ma, Jianxiang; Zhang, Yong; Li, Hao; Zhang, Xian

    2016-01-01

    Continuous cropping of watermelon (Citrullus lanatus L.) can lead to reduced yield and quality. We aimed to determine the effects of cattle manure addition and rotation with green garlic to improve yield and reduce disease incidence in watermelon and to examine the effects on the biological and chemical characteristics of the soil. Field experiments were performed during 2012-2014 on land previously under two years of continuous watermelon cropping in northwest China. We examined three treatment combinations: watermelon and garlic rotation, cattle manure application before watermelon planting, and combined cattle manure addition and crop rotation. Watermelon monoculture was retained as a control. Watermelon yield was significantly higher and disease incidence was lower in the treatments than the control. The populations of soil bacteria and actinomycetes and the bacteria/fungi ratio increased significantly and soil enzyme activities were generally enhanced under treatments. Available nutrients and soil organic matter contents were much higher under experimental treatments than the control. Results suggest both cattle manure application and garlic rotation can ameliorate the negative effects of continuous cropping. The combined treatment of cattle manure addition and green garlic rotation was optimal to increase yield, reduce disease incidence and enhance soil quality.

  16. Non-destructive evaluation of bacteria-infected watermelon seeds using visible/near-infrared hyperspectral imaging.

    PubMed

    Lee, Hoonsoo; Kim, Moon S; Song, Yu-Rim; Oh, Chang-Sik; Lim, Hyoun-Sub; Lee, Wang-Hee; Kang, Jum-Soon; Cho, Byoung-Kwan

    2017-03-01

    There is a need to minimize economic damage by sorting infected seeds from healthy seeds before seeding. However, current methods of detecting infected seeds, such as seedling grow-out, enzyme-linked immunosorbent assays, the polymerase chain reaction (PCR) and the real-time PCR have a critical drawbacks in that they are time-consuming, labor-intensive and destructive procedures. The present study aimed to evaluate the potential of visible/near-infrared (Vis/NIR) hyperspectral imaging system for detecting bacteria-infected watermelon seeds. A hyperspectral Vis/NIR reflectance imaging system (spectral region of 400-1000 nm) was constructed to obtain hyperspectral reflectance images for 336 bacteria-infected watermelon seeds, which were then subjected to partial least square discriminant analysis (PLS-DA) and a least-squares support vector machine (LS-SVM) to classify bacteria-infected watermelon seeds from healthy watermelon seeds. The developed system detected bacteria-infected watermelon seeds with an accuracy > 90% (PLS-DA: 91.7%, LS-SVM: 90.5%), suggesting that the Vis/NIR hyperspectral imaging system is effective for quarantining bacteria-infected watermelon seeds. The results of the present study show that it is possible to use the Vis/NIR hyperspectral imaging system for detecting bacteria-infected watermelon seeds. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  17. In vitro assessment of physiological changes of watermelon (Citrullus lanatus) upon iron oxide nanoparticles exposure.

    PubMed

    Wang, Yunqiang; Hu, Jing; Dai, Zhaoyi; Li, Junli; Huang, Jin

    2016-11-01

    With the rapid development of nanotechnology, developing nano iron fertilizer is an important strategy to alleviate Fe deficiency and elevate Fe fertilization effect in agricultural applications. In this study, watermelon seedlings were grown in soil amended with iron oxide nanoparticles (γ-Fe2O3 NPs) at different concentrations (0, 20, 50, 100 mg/L). The content of soluble sugar and protein, content of chlorophyll and malondialdehyde (MDA), and activity of antioxidant enzymes of watermelon leaves were determined in five successive weeks to evaluate the physiological changes of watermelon plants after γ-Fe2O3 NPs exposure. Transmission electron microscope (TEM) observations indicated that γ-Fe2O3 NPs could enter root cell of watermelon. Results showed that 20 mg/L γ-Fe2O3 NPs didn't cause any oxidative stress on watermelon and 50 mg/L γ-Fe2O3 NPs could increase soluble sugar, soluble protein and chlorophyll content in the growth of plants. In addition, 50 and 100 mg/L γ-Fe2O3 NPs caused oxidative stress on watermelon leaves, but this NP-induced stress was removed with the growth of watermelon. It is noteworthy that we found γ-Fe2O3 NPs might possess an intrinsic peroxidase-like activity. The variation trend of physiological parameters was correlated with the nutritional requirements of plants. It can be concluded that γ-Fe2O3 NPs at proper concentrations have the ability to improve iron deficiency chlorosis and promote the growth of watermelon plants. To the best of the author's knowledge, this is the first holistic study focusing on the impact of γ-Fe2O3 NPs in long-term experiment of watermelon plants. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  18. [Comparative study of the protein makeup in diploid and haploid forms of Saccharomyces and Pichia].

    PubMed

    Temina, A V; Tolstorukov, I I; Korogodin, V I; Gololobov, A D

    1979-01-01

    The rates of growth, biomass accumulation, and electrophoretic spectra of mobile cytoplasmic proteins were studied with nonisogenous haploid and diploid cultures of Saccharomyces cerevisiae and Pichia guilliermondii as well as with isogenous haploid-diploid pairs of Saccharomyces cerevisiae and Pichia pinus. On a mineral medium with glucose, differences in these parameters in various yeast strains were found to be due to the genotype of a strain rather than to ploidy: nonisogenous haploid and diploid cultures displayed considerable and random variability of these properties while no differences were found in isogenous haploid-diploid pairs. Studies on solubility of protein fractions in various solvents made it possible to reveal differences connected with ploidy, namely: both in nonisogenous and isogenous haploid-diploid systems, the content of the water-soluble fraction decreased in diploid cultures.

  19. Tetraploid citrus rootstocks are more tolerant to salt stress than diploid.

    PubMed

    Saleh, Basel; Allario, Thierry; Dambier, Dominique; Ollitrault, Patrick; Morillon, Raphaël

    2008-09-01

    Citrus trees are subject to several abiotic constraints such as salinity. Providing new rootstocks more tolerant is thus a requirement. In this article, we investigated salt stress tolerance of three tetraploid rootstock genotypes when compared to their respective diploid rootstocks (Poncirus trifoliata, Carrizo citrange, Cleopatra mandarin). Plant growth, leaf fall and ion contents were investigated. At the end of the experiment, leaf fall was observed only for diploid Poncirus trifoliata plants as well as chlorosis symptoms for Poncirus trifoliata and Carrizo citrange diploid plants. The diploid Cleopatra mandarin plants growth rate was not affected by salt stress and has even been increased for tetraploid Cleopatra mandarin. Ion contents investigation has shown lower accumulations of chloride ions in leaves of the tetraploid plants when compared to diploid plants. Our results suggest that citrus tetraploid rootstocks are more tolerant to salt stress than their corresponding diploid.

  20. Performance comparisons between diploid and triploid sunshine bass in fresh water ponds

    USGS Publications Warehouse

    Kerby, J.H.; Everson, J.M.; Harrell, R.M.; Geiger, J.G.; Starling, C.C.; Revels, H.

    2002-01-01

    Diploid and triploid sunshine bass (white bass ??? x striped bass ???) were produced in 1990 at Florida's Richloam Fish Hatchery. Triploidy was induced with hydrostatic pressure. Fry were cultured to phase I in earthen ponds in Webster and Gainesville, FL, and transported to Leetown, WV, where they were held in circular flow-through fiberglass tanks. Ploidy of treated fish was determined with a Coulter counter and triploids were segregated from diploids. In April 1991, control diploid and triploid populations were graded to remove the largest and smallest individuals, and four 0.2-ha hypalon-lined ponds were stocked with 600 fish each; two ponds contained triploids and two contained diploids. Triploids and diploids were not significantly different in average fork length (FL) or weight at stocking. Triploids averaged 231 mm and 181.2 g, compared to diploid averages of 233 mm and 188.9 g. Monthly samples indicated that diploids grew faster than triploids; mean weights and lengths were both significantly different after 3 months. When harvested in October, triploids averaged 358 mm and 867.9 g, whereas diploids averaged 381 mm and 1153.5 g. Survival of triploids and diploids was 97.0% and 95.9%, respectively. Mean standing crop was 2496.3 kg/ha for triploids and 3280.6 kg/ha for diploids. Male diploids and most female diploids were sexually mature at 2 years of age. Sterility of triploids was confirmed as gonads remained reduced and dysfunctional at 5 years of age. ?? 2002 Elsevier Science B.V. All rights reserved.

  1. The effects of frozen storage conditions on lycopene stability in watermelon tissue.

    PubMed

    Fish, Wayne W; Davis, Angela R

    2003-06-04

    The purpose of this investigation was to evaluate the rate of deterioration of lycopene in watermelon tissue during frozen storage, because little is known about the stability of watermelon tissue lycopene under cold storage conditions. Heart tissue from each of nine individual watermelons was stored at -20 or -80 degrees C as either small chunks or puree and periodically sampled over a year's time. Initial freeze-thaw experiments indicated that a small percentage of lycopene, approximately 4-6%, degraded during an initial freeze-thaw. Analyses of the samples showed a loss of approximately 30-40% lycopene over a year's storage at -20 degrees C and a loss of approximately 5-10% over the same period at -80 degrees C. Lycopene was slightly more stable in pureed compared with diced watermelon tissue at -20 degrees C, but not at -80 degrees C. The kinetic data were best fitted by application of two simultaneous, first-order decay processes. HPLC analysis of the samples after a year's storage suggested that beta-carotene was more stable during storage at -20 degrees C than was lycopene.

  2. USVL-370, A zucchini yellow mosaic virus resistant watermelon breeding line

    USDA-ARS?s Scientific Manuscript database

    We report the development of a novel watermelon line ‘USVL-370’ [Citrullus lanatus (Thunb.) Matsum. & Nakai] containing resistance to the zucchini yellow mosaic virus-Florida strain (ZYMV-FL). This breeding line is homozygous for the recessive eukaryotic elongation factor eIF4E allele associated wit...

  3. Turkmenistan Melon (Cucumis melo), and Watermelon (Citrullus lanatus) Germplasm Expedition 2008.

    USDA-ARS?s Scientific Manuscript database

    Turkmenistan has a rich tradition of melon (Cucumis melo L.) and watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai) production, but like in many countries land races and old varieties are in danger of genetic erosion. In July-August 2008, a collaborative Turkmenistan–United States germplasm exp...

  4. Molecular Characterization of Watermelon Chlorotic Stunt Virus (WmCSV) from Palestine

    PubMed Central

    Ali-Shtayeh, Mohammed S.; Jamous, Rana M.; Mallah, Omar B.; Abu-Zeitoun, Salam Y.

    2014-01-01

    The incidence of watermelon chlorotic stunt disease and molecular characterization of the Palestinian isolate of Watermelon chlorotic stunt virus (WmCSV-[PAL]) are described in this study. Symptomatic leaf samples obtained from watermelon Citrullus lanatus (Thunb.), and cucumber (Cucumis sativus L.) plants were tested for WmCSV-[PAL] infection by polymerase chain reaction (PCR) and Rolling Circle Amplification (RCA). Disease incidence ranged between 25%–98% in watermelon fields in the studied area, 77% of leaf samples collected from Jenin were found to be mixed infected with WmCSV-[PAL] and SLCV. The full-length DNA-A and DNA-B genomes of WmCSV-[PAL] were amplified and sequenced, and the sequences were deposited in the GenBank. Sequence analysis of virus genomes showed that DNA-A and DNA-B had 97.6%–99.42% and 93.16%–98.26% nucleotide identity with other virus isolates in the region, respectively. Sequence analysis also revealed that the Palestinian isolate of WmCSV shared the highest nucleotide identity with an isolate from Israel suggesting that the virus was introduced to Palestine from Israel. PMID:24956181

  5. Distribution of Four Viruses in Single and Mixed Infections Within Infected Watermelon Plants in Florida

    USDA-ARS?s Scientific Manuscript database

    Whitefly-transmitted Squash vein yellowing virus (SqVYV) and Cucurbit leaf crumple virus (CuLCrV), and aphid-transmitted Papaya ringspot virus type W (PRSV-W) have had serious impact on watermelon production in southwest and west-central Florida in recent years. Tissue blot nucleic acid hybridizati...

  6. Old Dogs, Children, and Watermelon Wine: Focus on the Older Adult Learner.

    ERIC Educational Resources Information Center

    Kasworm, Carol E.

    1978-01-01

    Three significant elements should be considered in offering educational programs for the older learner: acceptance (old dogs); support (God bless little children while they're too young to hate); and dependability (watermelon wine). Guidelines are offered for the teacher entering the classroom composed of adult learners. (KC)

  7. Food safety in Thailand 1: it is safe to eat watermelon and durian in Thailand.

    PubMed

    Wanwimolruk, Sompon; Kanchanamayoon, Onnicha; Boonpangrak, Somchai; Prachayasittikul, Virapong

    2015-05-01

    The wide use of pesticides raises serious concerns regarding food safety and environmental impacts. There is increasing public concern about the potential health risks linked with exposure to pesticides. Regulation of maximum residue limits (MRL) of pesticide residues in food commodities has been established in many developed countries. For developing countries, like Thailand, this regulation often exists in law, but is not completely enforced in practice. Thus, pesticide residue levels in vegetables and fruits have not been thoroughly monitored. The present study aimed to examine potential health risks associated with pesticide exposure by determining the pesticide residues in two commonly consumed fruits, watermelon and durian. The fruit samples were purchased from markets in central provinces of Thailand and assayed for the content of 28 pesticides. Analysis of pesticides was performed by multiresidue extraction and followed by GC-MS/MS detection. Of 28 pesticides investigated, 5 were detected in 90.7% of the watermelon samples (n = 75) and 3 in 90% of durian samples (n = 30). Carbofuran, chlorpyrifos, diazinon, dimethoate and metalaxyl were found in watermelons, whereas dichlorvos, dimethoate and metalaxyl were detected in durians. However, their levels were much lower than the recommended MRL values. These pesticide levels detected in the fruits are unlikely to harm the consumers; therefore it is safe to eat watermelon and durian in Thailand. While our results found negligible risk associated with pesticide exposure from consuming these common tropical fruits, special precautions should be considered to decrease total exposure to these harmful pesticides from various foods.

  8. Comparative transcriptome analysis of two contrasting watermelon genotypes during fruit development and ripening.

    PubMed

    Zhu, Qianglong; Gao, Peng; Liu, Shi; Zhu, Zicheng; Amanullah, Sikandar; Davis, Angela R; Luan, Feishi

    2017-01-03

    Watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] is an economically important crop with an attractive ripe fruit that has colorful flesh. Fruit ripening is a complex, genetically programmed process. In this study, a comparative transcriptome analysis was performed to identify the regulators and pathways that are involved in the fruit ripening of pale-yellow-flesh cultivated watermelon (COS) and red-flesh cultivated watermelon (LSW177). We first identified 797 novel genes to extend the available reference gene set. Second, 3958 genes in COS and 3503 genes in LSW177 showed at least two-fold variation in expression, and a large number of these differentially expressed genes (DEGs) during fruit ripening were related to carotenoid biosynthesis, plant hormone pathways, and sugar and cell wall metabolism. Third, we noted a correlation between ripening-associated transcripts and metabolites and the key function of these metabolic pathways during fruit ripening. The results revealed several ripening-associated actions and provide novel insights into the molecular mechanisms underlying the regulation of watermelon fruit ripening.

  9. Nature’s packaging and organization of carotenoids in watermelon and cantaloupe chromoplasts

    USDA-ARS?s Scientific Manuscript database

    As a means to better understand factors influencing the bioavailability of carotenoids from natural sources, the properties of plant-derived precipitates of watermelon lycopene and cantaloupe B-carotene were examined in an aqueous environment. Electron microscopy and chemical analyses revealed that...

  10. Rootstock of interspecific squash hybrids (Cucurbita maxima x Cucurbita moschata) increases lycopene content of watermelon

    USDA-ARS?s Scientific Manuscript database

    The watermelon industry in the U.S. is facing increased soil-borne disease pressure and the loss of the soil fumigant methyl bromide. To combat this, grafting of scions with disease-resistant rootstocks of cucurbit species has garnered widespread interest. Both scion and rootstock can affect plant...

  11. Identification and Utility of Markers Linked to the Zucchini Yellow Mosaic Virus Resistance Gene in Watermelon

    USDA-ARS?s Scientific Manuscript database

    Zucchini yellow mosaic virus Florida stain (ZYMV-FL) is one of the most economically important viruses affecting watermelon in the United States. Inheritance of resistance to ZYMV-FL is conferred by a single recessive gene. Described here is single-reaction, polymerase chain reaction-based marker l...

  12. A survey of bee species found pollinating watermelons in the Lower Rio Grande Valley of Texas

    USDA-ARS?s Scientific Manuscript database

    Using a combination of flower traps and visual observations, we surveyed three watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] fields in the Lower Rio Grande Valley to determine what bees inhabit this crop in this region. No managed honey bee (Apis mellifera L.) hives were in any of the fie...

  13. Patterns of Virus Distribution in Single and Mixed Infections of Florida Watermelons

    USDA-ARS?s Scientific Manuscript database

    Whitefly-transmitted Squash vein yellowing virus (SqVYV) and Cucurbit leaf crumple virus (CuLCrV), and aphid-transmitted Papaya ringspot virus type W (PRSV-W) have had serious impact on watermelon production in southwest and west-central Florida in recent years. Tissue blot nucleic acid hybridizati...

  14. Patterns of Virus Distribution in Single and Mixed Infections of Florida Watermelons

    USDA-ARS?s Scientific Manuscript database

    Whitefly-transmitted Squash vein yellowing virus (SqVYV) and Cucurbit leaf crumple virus (CuLCrV), and aphid-transmitted Papaya ringspot virus type W (PRSV-W) have had serious impact on watermelon production in southwest and west-central Florida in recent years. To determine the distribution of vir...

  15. Old Dogs, Children, and Watermelon Wine: Focus on the Older Adult Learner.

    ERIC Educational Resources Information Center

    Kasworm, Carol E.

    1978-01-01

    Three significant elements should be considered in offering educational programs for the older learner: acceptance (old dogs); support (God bless little children while they're too young to hate); and dependability (watermelon wine). Guidelines are offered for the teacher entering the classroom composed of adult learners. (KC)

  16. Radio Frequency (RF) dielectric properties of honeydew melon and watermelon juice and correlations with sugar content

    USDA-ARS?s Scientific Manuscript database

    Dielectric properties of juice of three honeydew melon cultivars and four watermelon cultivars of different maturities were measured with an open-ended coaxial-line probe and impedance analyzer over the frequency range from 10 MHz to 1.8 GHz. Soluble solids content (SSC) of fruit juice and moisture ...

  17. USVL-380, A zucchini yellow mosaic virus resistant watermelon breeding line

    USDA-ARS?s Scientific Manuscript database

    We report the development of a novel watermelon line ‘USVL-380’ [Citrullus lanatus (Thunb.) Matsum. & Nakai] resistant to the zucchini yellow mosaic virus-Florida strain (ZYMV-FL). This breeding line is homozygous for the recessive eukaryotic elongation factor eIF4E allele associated with ZYMV-resis...

  18. RKVL-318, a root-knot nematode resistant rootstock line for grafted watermelon

    USDA-ARS?s Scientific Manuscript database

    The Agriculture Research Service, U.S. Department of Agriculture, announces the release of ‘RKVL-318’, a novel germplasm line useful as a rootstock and as a genetic resource for enhancing resistance to root-knot nematodes (RKN) in watermelon cultivars. ‘RKVL-318’ is derived from the wild-type water...

  19. Resistant Citrullus lanatus var. citroides Rootstocks for Managing Root-knot Nematodes in Grafted Watermelon

    USDA-ARS?s Scientific Manuscript database

    Southern root-knot nematode (RKN), Meloidogyne incognita, is an important re-emerging pest of watermelon. Several factors have contributed to re-emergence of RKN including: 1) ban of methyl bromide for soil fumigation; 2) reduced land area for crop rotation; and 3) continuous cropping of cucurbits u...

  20. Mechanism of disease suppression of Fusarium wilt of watermelon by cover crop green manures

    USDA-ARS?s Scientific Manuscript database

    A fall planted Vicia villosa cover crop incorporated in spring as a green manure can suppress Fusarium wilt [Fusarium oxysporum f. sp. niveum (FON)] of watermelon in Maryland and Delaware. Experiments were conducted to determine whether the mechanism of this suppression was general or specific, and ...

  1. First report of Squash vein yellowing virus in watermelon in Guatemala

    USDA-ARS?s Scientific Manuscript database

    In this study, we report the first detection of Squash vein yellowing virus (SqVYV)-induced watermelon vine decline in Central America. Symptoms including wilt and collapse of plants at harvest, and non-marketable fruits with internal rind necrosis were observed. This report provides an overview o...

  2. Identification of unique volatile compounds associated with repelling whiteflies (Hemiptera: Aleyrodidae) in desert watermelon (Citrullus colocynthis)

    USDA-ARS?s Scientific Manuscript database

    Commercial watermelon cultivars (Citrullus lanatus var. lanatus) share a narrow genetic base and are susceptible to many insect pests and diseases. The insects include whiteflies which cause serious economic damages to this important cucurbit crop. However, several United States Plant Introduction a...

  3. Host resistance to phytophthora fruit rot in U.S. watermelon plant introductions

    USDA-ARS?s Scientific Manuscript database

    Phytophthora capsici, distributed worldwide, is an aggressive pathogen with a broad host range, infecting solanaceous, leguminaceous, and cucurbitaceous crops. Phytophthora fruit rot of watermelon (Citrullus lanatus) caused by P. capsici was first reported in the U.S. in 1940. Since then, the dise...

  4. Flesh color inheritance and gene interactions among canary yellow, pale yellow and red watermelon

    USDA-ARS?s Scientific Manuscript database

    Two loci, C and i-C were previously reported to determine flesh color between canary yellow and red watermelon. Recently LCYB was found as a color determinant gene for canary yellow (C) and co-dominant CAPS marker was developed to identify canary yellow and red alleles. Another report suggested th...

  5. Epidemiology and Association of Four Insect-Vectored Viruses in Florida Watermelon

    USDA-ARS?s Scientific Manuscript database

    Whitefly-transmitted Squash vein yellowing virus (SqVYV), Cucurbit leaf crumple virus (CuLCrV), Cucurbit yellow stunting disorder virus (CYSDV) and aphid-transmitted Papaya ringspot virus type W (PRSV-W) have had serious impact on watermelon production in southwest and west-central Florida in the pa...

  6. Use of external indicators to predict maturity of mini-watermelon fruit

    USDA-ARS?s Scientific Manuscript database

    Personal-size watermelon [Citrullus lanatus (Thunb.)], cultivars Valdoria and Vanessa were evaluated at 20, 30, 40 or 50 days after anthesis to determine a means of determining maturity at harvest. Fruit circumference, weight, ground-spot color, and number of senescent tendrils were measured for ea...

  7. Linkage mapping in a watermelon population segregating for fusarium wilt resistance

    Treesearch

    Leigh K. Hawkins; Fenny Dane; Thomas L. Kubisiak; Billy B. Rhodes; Robert L. Jarret

    2001-01-01

    Isozyme, randomly amplified polymorphic DNA (RAPD), and simple sequence repeats (SSR) markers were used to generate a linkage map in an F2 and F3 watermelon (Citrullus lanatus (Thumb.) Matsum. & Nakai) population derived from a cross between the fusarium wilt (Fusarium oxysporum f....

  8. Evaluation of Watermelon Plant Introductions (PI) for Tolerance to Phytophthora Fruit Rot, 2010

    USDA-ARS?s Scientific Manuscript database

    This experiment was conducted at the US Vegetable Laboratory farm in Charleston, SC. The soil was Yonges loamy fine sand. In 2009, we evaluated about 180 plant introductions (PI) belonging to the watermelon core collection with the USDA, ARS, germplasm resources information network (GRIN). Based...

  9. A Glance at Microsatellite Motifs from 454 Sequencing Reads of Watermelon Genomic DNA

    USDA-ARS?s Scientific Manuscript database

    A single 454 (Life Sciences Sequencing Technology) run of Charleston Gray watermelon (Citrullus lanatus var. lanatus) genomic DNA was performed and sequence data were assembled. A large scale identification of simple sequence repeat (SSR) was performed and SSR sequence data were used for the develo...

  10. A major quantitative trait locus is associated with Fusarium Wilt Race 1 resistance in watermelon

    USDA-ARS?s Scientific Manuscript database

    Fusarium wilt is a major disease of watermelon caused by the soil-borne fungus Fusarium oxysporum Schlechtend.:Fr. f. sp. niveum (E.F. Sm.) W.C. Snyder & H.N. Hans (Fon). A genetic population of 186 F3 families (24 plants in each family) exhibited continuous segregation for Fon race 1 response. Geno...

  11. Microplot Evaluation of Rootstocks for Control of Meloidogyne incognita on Grafted Tomato, Muskmelon, and Watermelon

    USDA-ARS?s Scientific Manuscript database

    Microplot experiments were conducted over two years (four growing seasons) to evaluate Meloidogyne incognita resistance in rootstocks used for grafted tomato (Solanum lycopersicum), muskmelon (Cucumis melo), and watermelon (Citrullus lanatus). Three tomato rootstocks; ‘TX301’, ‘Multifort’, and ‘Alo...

  12. Resistance for watermelon (Citrullus lanatus var. lanatus) against whiteflies (Hemiptera: Aleyrodidae)

    USDA-ARS?s Scientific Manuscript database

    The sweetpotato whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae), is an important global pest with and an extensive host range. Watermelon (Citrullus lanatus var. lanatus) is among the crops damaged by this pest. Host plant resistance is the foundation for the management of crops pests in general. ...

  13. Evaluation of Cultural Practices and Fungicides for Managing Phytophthora Fruit Rot of Watermelon, 2008

    USDA-ARS?s Scientific Manuscript database

    The experiment was conducted to evaluate the efficacy of new fungicides to manage Phytophthora fruit rot of watermelon. The soil at the experimental field in Charleston, SC, was Yonges loamy fine sand. The field was sprayed with Roundup Pro (1 pt/A) and Strategy (2 pt/A) after bedding but prior to...

  14. Waste cotton as a biodegradable mulching material for transplanted watermelon and cantaloupe production

    USDA-ARS?s Scientific Manuscript database

    Low-density polyethylene (LDPE) mulch is commonly used in transplanted vegetable crop production in the southeastern U. S. Cantaloupe and watermelon growers use a system of hybrid transplants, grown on narrow LDPE mulch-covered seedbeds with overhead irrigation, and use the mulch cover for only one...

  15. Effect of grafting on resistant rootstocks on development of powdery mildew on susceptible watermelon scion, 2012

    USDA-ARS?s Scientific Manuscript database

    An experiment was conducted in a greenhouse at the U.S. Vegetable Laboratory in Charleston, SC, to determine if grafting a powdery mildew susceptible variety (scion) onto watermelon rootstocks with resistance to powdery mildew would provide resistance to foliage of the susceptible scion. Plants of ...

  16. Purple Nutsedge Tuber Productivity as Affected by Organic Mulches in a Watermelon Production System

    USDA-ARS?s Scientific Manuscript database

    Research was conducted in Isabela, Puerto Rico, to determine the tuber productivity of the weed purple nutsedge (PN) and the yield of ‘Crimson Sweet' watermelon when grown with or without organic soil bed mulches [hays of millet (Pennisetum glaucum), nutsedge (Cyperus rotundus), sunnhemp (Crotalaria...

  17. Screening the USDA watermelon germplasm collection for drought tolerance at the seedling stage

    USDA-ARS?s Scientific Manuscript database

    Because of the growing threat of global warming, drought stress could severely affect the normal growth and development of crop plants. To alleviate such adverse effect, there is a need to screen watermelon germplasm collections to identify genetic sources for potential drought tolerance. In the pre...

  18. Spatial accumulation pattern of citrulline and other nutrients in immature and mature watermelon fruits.

    PubMed

    Akashi, Kinya; Mifune, Yuki; Morita, Kaori; Ishitsuka, Souichi; Tsujimoto, Hisashi; Ishihara, Toshiyuki

    2017-01-01

    Watermelon (Citrullus lanatus L.) originates from arid regions of southern Africa, and its fruit contains a large amount of the amino acid citrulline, an efficient hydroxyl radical scavenger. Citrulline is implicated in the production of nitric oxide in human endothelium, and potential health benefits including vasodilatation and antioxidant functions have been suggested. However, citrulline metabolism in watermelon fruits is poorly understood. This study examined the accumulation pattern of citrulline and other nutrients in immature and mature watermelon fruits. In mature fruits, highest citrulline concentration was observed in the outer peel, followed by the central portion of the flesh and inner rinds, whereas the level was lower in the peripheral portion of the flesh. Citrulline content was generally low in immature fruits. Spatial and developmental patterns of citrulline accumulation were largely different from those of the antioxidant lycopene, total proteins, and soluble sugars such as glucose, fructose, and sucrose. Principal component analysis suggested a clear distinction of the central flesh and outer peels in mature fruits from other tissues in terms of the levels of major nutrients. These observations suggested that citrulline accumulation may be regulated in a distinct manner from other nutrients during watermelon fruit maturation. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  19. Improved watermelon quality using bottle gourd rootstock expressing a Ca(2+)/H(+) antiporter

    USDA-ARS?s Scientific Manuscript database

    Bottle gourd ("Lagenaria siceraria" Standl.) has been commonly used as a source of rootstock for watermelon. To improve its performance as a rootstock without adverse effects on the scion, the bottle gourd was genetically engineered using a modified "Arabidopsis" Ca(2+)/H(+) exchanger sCAX2B. This t...

  20. Tolerance to powdery mildew conferred in susceptible watermelon scion by grafting on resistant rootstocks

    USDA-ARS?s Scientific Manuscript database

    Cucurbit powdery mildew (PM) caused by Podosphaera xanthii, can impact seedling growth and cause serious losses in greenhouse and open field production. We have developed several watermelon and bottle gourd germplasm lines with high levels of resistance to PM. A PM susceptible cultivar Mickey Lee ...

  1. Pilot survey results to prioritize research needs in the watermelon industry

    USDA-ARS?s Scientific Manuscript database

    It is useful for researchers of any commodity to occasionally survey their clientele to monitor for new developments and make sure their research is focused on major problems. A discussion at the Watermelon Research and Development Working Group meeting in Asheville, NC (2006) led to the development...

  2. L-citrulline levels in watermelon cultigens tested in two environments

    USDA-ARS?s Scientific Manuscript database

    Melon producers face increasing production costs and international market competition. Maximizing marketability of high quality watermelon [Citrullus lanatus (Thunb.) Matsum. and Nakai], that also contain high levels of the amino acid phytonutrient L-citrulline, can provide new market niches for th...

  3. Interference of Griseofulvin with the Segregation of Chromosomes at Mitosis in Diploid Aspergillus nidulans

    PubMed Central

    Kappas, A.; Georgopoulos, S. G.

    1974-01-01

    Low concentrations of the antibiotic griseofulvin were found to cause increased frequencies of somatic segregation due to chromosome nondisjunction in a diploid strain of Aspergillus nidulans. PMID:4600705

  4. The association between polyploidy and clonal reproduction in diploid and tetraploid Chamerion angustifolium.

    PubMed

    Baldwin, Sarah J; Husband, Brian C

    2013-04-01

    Clonal reproduction is associated with the incidence of polyploidy in flowering plants. This pattern may arise through selection for increased clonality in polyploids compared to diploids to reduce mixed-ploidy mating. Here, we test whether clonal reproduction is greater in tetraploid than diploid populations of the mixed-ploidy plant, Chamerion angustifolium, through an analysis of the size and spatial distribution of clones in natural populations using AFLP genotyping and a comparison of root bud production in a greenhouse study. Natural tetraploid populations (N = 5) had significantly more AFLP genotypes (x¯ = 10.8) than diploid populations (x¯ = 6.0). Tetraploid populations tended to have fewer ramets per genotype and fewer genotypes with >1 ramet. In a spatial autocorrelation analysis, ramets within genotypes were more spatially aggregated in diploid populations than in tetraploid populations. In the greenhouse, tetraploids allocated 90.4% more dry mass to root buds than diploids, but tetraploids produced no more root buds and 44% fewer root buds per unit root mass than diploids. Our results indicate that clonal reproduction is significant in most populations, but tetraploid populations are not more clonal than diploids, nor are their clones more spatially aggregated. As a result, tetraploids may be less sheltered from mixed-ploidy mating and diploids more exposed to inbreeding, the balance of which could influence the establishment of tetraploids in diploid populations.

  5. Alkaloid spectrum in diploid and tetraploid hairy root cultures of Datura stramonium.

    PubMed

    Berkov, Strahil; Pavlov, Atanas; Kovatcheva, Petia; Stanimirova, Pepa; Philipov, Stefan

    2003-01-01

    Hairy root cultures were obtained from diploid and induced tetraploid plants of Datura stramonium and analyzed by gas chromatography/mass spectrometry. Twenty alkaloids (19 for diploid and 9 for tetraploid hairy root cultures) were identified. A new tropane ester 3-tigloyloxy-6-propionyloxy-7-hydroxytropane was identified on the basis of mass spectral data. Hyoscyamine was the main alkaloid in both diploid and tetraploid cultures. In contrast to diploid hairy roots, the percentage contributions of the alkaloids, with exceptions for hyoscyamine and apoatropine, were higher in the total alkaloid mixture of tetraploid hairy roots.

  6. Abscisic acid pathway involved in the regulation of watermelon fruit ripening and quality trait evolution

    PubMed Central

    Wang, Yanping; Guo, Shaogui; Tian, Shouwei; Zhang, Jie; Ren, Yi; Sun, Honghe; Gong, Guoyi; Zhang, Haiying; Xu, Yong

    2017-01-01

    Watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai) is a non-climacteric fruit. The modern sweet-dessert watermelon is the result of years of cultivation and selection for fruits with desirable qualities. To date, the mechanisms of watermelon fruit ripening, and the role of abscisic acid (ABA) in this process, has not been well understood. We quantified levels of free and conjugated ABA contents in the fruits of cultivated watermelon (97103; C. lanatus subsp. vulgaris), semi-wild germplasm (PI179878; C. lanatus subsp. mucosospermus), and wild germplasm (PI296341-FR; C. lanatus subsp. lanatus). Results showed that ABA content in the fruits of 97103 and PI179878 increased during fruit development and ripening, but maintained a low steady state in the center flesh of PI296341-FR fruits. ABA levels in fruits were highest in 97103 and lowest in PI296341-FR, but no obvious differences in ABA levels were observed in seeds of these lines. Examination of 31 representative watermelon accessions, including different C. lanatus subspecies and ancestral species, showed a correlation between soluble solids content (SSC) and ABA levels in ripening fruits. Furthermore, injection of exogenous ABA or nordihydroguaiaretic acid (NDGA) into 97103 fruits promoted or inhibited ripening, respectively. Transcriptomic analyses showed that the expression levels of several genes involved in ABA metabolism and signaling, including Cla009779 (NCED), Cla005404 (NCED), Cla020673 (CYP707A), Cla006655 (UGT) and Cla020180 (SnRK2), varied significantly in cultivated and wild watermelon center flesh. Three SNPs (-738, C/A; -1681, C/T; -1832, G/T) in the promoter region of Cla020673 (CYP707A) and one single SNP (-701, G/A) in the promoter of Cla020180 (SnRK2) exhibited a high level of correlation with SSC variation in the 100 tested accessions. Our results not only demonstrate for the first time that ABA is involved in the regulation of watermelon fruit ripening, but also provide insights into the

  7. Comparative genomics reveals candidate carotenoid pathway regulators of ripening watermelon fruit

    PubMed Central

    2013-01-01

    Background Many fruits, including watermelon, are proficient in carotenoid accumulation during ripening. While most genes encoding steps in the carotenoid biosynthetic pathway have been cloned, few transcriptional regulators of these genes have been defined to date. Here we describe the identification of a set of putative carotenoid-related transcription factors resulting from fresh watermelon carotenoid and transcriptome analysis during fruit development and ripening. Our goal is to both clarify the expression profiles of carotenoid pathway genes and to identify candidate regulators and molecular targets for crop improvement. Results Total carotenoids progressively increased during fruit ripening up to ~55 μg g-1 fw in red-ripe fruits. Trans-lycopene was the carotenoid that contributed most to this increase. Many of the genes related to carotenoid metabolism displayed changing expression levels during fruit ripening generating a metabolic flux toward carotenoid synthesis. Constitutive low expression of lycopene cyclase genes resulted in lycopene accumulation. RNA-seq expression profiling of watermelon fruit development yielded a set of transcription factors whose expression was correlated with ripening and carotenoid accumulation. Nineteen putative transcription factor genes from watermelon and homologous to tomato carotenoid-associated genes were identified. Among these, six were differentially expressed in the flesh of both species during fruit development and ripening. Conclusions Taken together the data suggest that, while the regulation of a common set of metabolic genes likely influences carotenoid synthesis and accumulation in watermelon and tomato fruits during development and ripening, specific and limiting regulators may differ between climacteric and non-climacteric fruits, possibly related to their differential susceptibility to and use of ethylene during ripening. PMID:24219562

  8. The effects of watermelon (Citrullus lanatus) extracts and L-citrulline on rat uterine contractility.

    PubMed

    Munglue, Phukphon; Eumkep, Graingsak; Wray, Susan; Kupittayanant, Sajeera

    2013-04-01

    In uterine smooth muscle, the effects of watermelon and its citrulline content are unknown. The aims of this study were therefore, to determine the effects of watermelon extract and citrulline on the myometrium and to investigate their mechanisms of action. The effects of extracts of watermelon flesh and rind and L-citrulline (64 μmol/L) were evaluated on 3 types of contractile activity; spontaneous, those elicited by potassium chloride (KCl) depolarization, or oxytocin (10 nmol/L) application in isolated rat uterus. Inhibitors of nitric oxide (NO) and its mechanisms of action, N ω-Nitro-L-arginine methyl ester hydrochloride (L-NAME, 100 μmol/L), LY83583 (1 μmol/L), and tetraethylamonium chloride (5 mmol/L), as well as Ca signaling pathways, were determined. Both flesh and rind extracts significantly decreased the force produced by all 3 mechanisms, in a dose-dependent manner. The extracts could also significantly decrease the force under conditions of sustained high Ca levels (depolarization and agonist) and when the force was produced only by sarcoplasmic reticulum (SR) Ca release. L-citrulline produced the same effects on force as watermelon extracts. With submaximal doses of extract, the additive effects of L-citrulline were found. The inhibitory effects of extracts and L-citrulline were reversed upon the addition of NO inhibitors, and pretreatment of tissues with these inhibitors prevented the actions of both extracts and L-citrulline. Thus, these data show that watermelon and citrulline are potent tocolytics, decreasing the force produced by calcium entry and SR release and arising by different pathways, including oxytocin stimulation. Their major mechanism is to stimulate the NO-cyclic guanosine monophosphate (cGMP) relaxant pathway.

  9. Characterization of Melon necrotic spot virus Occurring on Watermelon in Korea.

    PubMed

    Kwak, Hae-Ryun; Kim, Jeong-Soo; Cho, Jeom-Deog; Lee, Joong-Hwan; Kim, Tae-Sung; Kim, Mi-Kyeong; Choi, Hong-Soo

    2015-12-01

    Melon necrotic spot virus (MNSV) was recently identified on watermelon (Citrullus vulgaris) in Korea, displaying as large necrotic spots and vein necrosis on the leaves and stems. The average occurrence of MNSV on watermelon was found to be 30-65% in Hapcheon and Andong City, respectively. Four isolates of the virus (MNSV-HW, MNSV-AW, MNSV-YW, and MNSV-SW) obtained from watermelon plants in different areas were non-pathogenic on ten general indicator plants, including Chenopodium quinoa, while they infected systemically six varieties of Cucurbitaceae. The virus particles purified by 10-40% sucrose density gradient centrifugation had a typical ultraviolet spectrum, with a minimum at 245 nm and a maximum at 260 nm. The morphology of the virus was spherical with a diameter of 28-30 nm. Virus particles were observed scattered throughout the cytoplasm of watermelon cells, but no crystals were detected. An ELISA was conducted using antiserum against MNSV-HW; the optimum concentrations of IgG and conjugated IgG for the assay were 1 μl/ml and a 1:8,000-1:10,000 dilutions, respectively. Antiserum against MNSV-HW could capture specifically both MNSV-MN from melon and MNSV-HW from watermelon by IC/RT-PCR, and they were effectively detected with the same specific primer to produce product of 1,172 bp. The dsRNA of MNSV-HW had the same profile (4.5, 1.8, and 1.6 kb) as that of MNSV-MN from melon. The nucleotide sequence of the coat protein of MNSV-HW gave a different phylogenetic tree, having 17.2% difference in nucleotide sequence compared with MNSV isolates from melon.

  10. Comparative genomics reveals candidate carotenoid pathway regulators of ripening watermelon fruit.

    PubMed

    Grassi, Stefania; Piro, Gabriella; Lee, Je Min; Zheng, Yi; Fei, Zhangjun; Dalessandro, Giuseppe; Giovannoni, James J; Lenucci, Marcello S

    2013-11-12

    Many fruits, including watermelon, are proficient in carotenoid accumulation during ripening. While most genes encoding steps in the carotenoid biosynthetic pathway have been cloned, few transcriptional regulators of these genes have been defined to date. Here we describe the identification of a set of putative carotenoid-related transcription factors resulting from fresh watermelon carotenoid and transcriptome analysis during fruit development and ripening. Our goal is to both clarify the expression profiles of carotenoid pathway genes and to identify candidate regulators and molecular targets for crop improvement. Total carotenoids progressively increased during fruit ripening up to ~55 μg g(-1) fw in red-ripe fruits. Trans-lycopene was the carotenoid that contributed most to this increase. Many of the genes related to carotenoid metabolism displayed changing expression levels during fruit ripening generating a metabolic flux toward carotenoid synthesis. Constitutive low expression of lycopene cyclase genes resulted in lycopene accumulation. RNA-seq expression profiling of watermelon fruit development yielded a set of transcription factors whose expression was correlated with ripening and carotenoid accumulation. Nineteen putative transcription factor genes from watermelon and homologous to tomato carotenoid-associated genes were identified. Among these, six were differentially expressed in the flesh of both species during fruit development and ripening. Taken together the data suggest that, while the regulation of a common set of metabolic genes likely influences carotenoid synthesis and accumulation in watermelon and tomato fruits during development and ripening, specific and limiting regulators may differ between climacteric and non-climacteric fruits, possibly related to their differential susceptibility to and use of ethylene during ripening.

  11. Characterization of Melon necrotic spot virus Occurring on Watermelon in Korea

    PubMed Central

    Kwak, Hae-Ryun; Kim, Jeong-Soo; Cho, Jeom-Deog; Lee, Joong-Hwan; Kim, Tae-sung; Kim, Mi-Kyeong; Choi, Hong-Soo

    2015-01-01

    Melon necrotic spot virus (MNSV) was recently identified on watermelon (Citrullus vulgaris) in Korea, displaying as large necrotic spots and vein necrosis on the leaves and stems. The average occurrence of MNSV on watermelon was found to be 30–65% in Hapcheon and Andong City, respectively. Four isolates of the virus (MNSV-HW, MNSV-AW, MNSV-YW, and MNSV-SW) obtained from watermelon plants in different areas were non-pathogenic on ten general indicator plants, including Chenopodium quinoa, while they infected systemically six varieties of Cucurbitaceae. The virus particles purified by 10–40% sucrose density gradient centrifugation had a typical ultraviolet spectrum, with a minimum at 245 nm and a maximum at 260 nm. The morphology of the virus was spherical with a diameter of 28–30 nm. Virus particles were observed scattered throughout the cytoplasm of watermelon cells, but no crystals were detected. An ELISA was conducted using antiserum against MNSV-HW; the optimum concentrations of IgG and conjugated IgG for the assay were 1 μl/ml and a 1:8,000–1:10,000 dilutions, respectively. Antiserum against MNSV-HW could capture specifically both MNSV-MN from melon and MNSV-HW from watermelon by IC/RT-PCR, and they were effectively detected with the same specific primer to produce product of 1,172 bp. The dsRNA of MNSV-HW had the same profile (4.5, 1.8, and 1.6 kb) as that of MNSV-MN from melon. The nucleotide sequence of the coat protein of MNSV-HW gave a different phylogenetic tree, having 17.2% difference in nucleotide sequence compared with MNSV isolates from melon. PMID:26673673

  12. RNA sequencing reveals high resolution expression change of major plant hormone pathway genes after young seedless grape berries treated with gibberellin.

    PubMed

    Chai, Lijuan; Li, Yanmei; Chen, Shangwu; Perl, Avihai; Zhao, Fengxia; Ma, Huiqin

    2014-12-01

    Seedless varieties are of particular importance to the table-grape and raisin industries. Gibberellin (GA) application is widely used in the early stages of seedless berry development to increase berry size and economic value. However, the underlying mechanism of GA induction of berry enlargement is not well understood. Here, RNA-sequencing analysis of 'Centennial Seedless' (Vitis vinifera L.) berries treated with GA3 12 days after flowering is reported. Pair-wise comparison of GA3-treated and control samples detected 165, 444, 463 genes with an over two-fold change in expression 1, 3, and 7 days after GA3 treatment, respectively. The number of differentially expressed genes increased with time after GA3 treatment, and the differential expression was dominated by downregulation. Significantly modulated expression included genes encoding synthesis and catabolism to manage plant hormone homeostasis, hormone transporters, receptors and key components in signaling pathways; exogenous GA3 induced multipoint cross talk with auxin, cytokinin, brassinosteroid, ABA and ethylene. The temporal gene-expression patterns of cell-wall-modification enzymes, cytoskeleton and membrane components and transporters revealed a pivotal role for cell-wall-relaxation genes in GA3-induced berry enlargement. Our results provide the first sequential transcriptomic atlas of exogenous GA3-induced berry enlargement and reveal the complexity of GA3's effect on berry sizing.

  13. Study of free and glycosidically bound volatile compounds in air-dried raisins from three seedless grape varieties using HS-SPME with GC-MS.

    PubMed

    Wang, Dong; Cai, Jian; Zhu, Bao-Qing; Wu, Guang-Feng; Duan, Chang-Qing; Chen, Guang; Shi, Ying

    2015-06-15

    Volatile compounds in air-dried raisins from Turpan, China were analysed, with 77 volatiles identified in Flame Seedless, Thompson Seedless, and Crimson Seedless raisins, 37 of which had never been reported as raisin volatiles. Odour activity values (OAVs) of these volatiles were calculated; 20 compounds had OAVs above 1. The aroma characters of the three varieties were quite similar except for some differences in the intensity of each aroma character. The main free-form volatiles were ethyl acetate, hexanoic acid, (E,E)-2,4-heptadienal and geraniol, with β-damascenone, 3-ethyl-2,5-dimethylpyrazine, 1-octen-3-ol and hexanal making the highest contribution to the aroma. Fruity and floral were the main characteristics of the free-form aromas in raisins. The main bound-form volatiles were benzyl alcohol and acetoin, with β-damascenone contributing most to the bound-form aromas, enhancing the floral, fruity and fatty aroma. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Kinetics of staurosporine-arrest of human diploid fibroblasts

    SciTech Connect

    Stevenson, A.P.; Bustos, L.D.; Dickson, J.A.; Habbersett, R.C.; Crissman, H.A. )

    1993-01-01

    The authors have previously shown that the general protein kinase inhibitor, staurosporine (Stsp), has a differential effect on the progression of normal and transformed cells. Low levels of Stsp (1.0 ng/ml) reversibly arrested normal diploid cells in early G1 phase, whereas concentrations of Stsp as high as 50-75 ng/ml had no effect on G1 progression in transformed cells. High concentrations of Stsp arrested normal cells in G1 and G2 phases but blocked transformed cells only in G2 phase of the cell cycle. To follow the accumulation of cells in G1 and/or G2 phases, asynchronous cultures of human diploid fibroblasts were treated with 0, 1, 5, 10, 20, 30 or 50 ng/ml staurosporine for 18 hours in the presence of bromodeoxyuridine. The kinetics of labeling with BrdU were determined with a two-laser flow cytometric technique that monitored emission of fluorescence from DNA-species stains that differed in the degree of BrdU-induced quenching of their fluorescence signals. Bivariate plots of Hoechst/mithramycin fluorescence signal ratio vs. Hoechst fluorescence identified the arrested cells as cohorts of cells in different positions across cell cycle at the time of Stsp addition.

  15. Spatial heterogeneity and the evolution of sex in diploids.

    PubMed

    Agrawal, Aneil F

    2009-07-01

    Much of the theoretical work on the evolution of sex has focused on the effects of recombination. In diploids, segregation also occurs during sexual reproduction. Segregation breaks down some types of genetic associations that are not affected by recombination and thus influences the evolution of sex in ways that are not apparent from studying the evolution of recombination as a surrogate for sex. Here I examine the evolution of sex in diploids experiencing spatially heterogeneous selection. If divergent selection causes genetic differentiation, then migration can be a powerful force generating genetic associations that may not be favored by selection. An advantage to sex can arise from breaking down these associations. By examining modifiers of both sex and recombination, the model allows for a direct comparison of the forces acting on these related but different processes, illuminating the role of segregation. The model also includes inbreeding, which has been shown to be important for both segregation and recombination. I find that inbreeding affects the evolution of sex through segregation, not recombination. Several suggestions for empirical experiments are given.

  16. Deleterious mutations and selection for sex in finite diploid populations.

    PubMed

    Roze, Denis; Michod, Richard E

    2010-04-01

    In diploid populations, indirect benefits of sex may stem from segregation and recombination. Although it has been recognized that finite population size is an important component of selection for recombination, its effects on selection for segregation have been somewhat less studied. In this article, we develop analytical two- and three-locus models to study the effect of recurrent deleterious mutations on a modifier gene increasing sex, in a finite diploid population. The model also incorporates effects of mitotic recombination, causing loss of heterozygosity (LOH). Predictions are tested using multilocus simulations representing deleterious mutations occurring at a large number of loci. The model and simulations show that excess of heterozygosity generated by finite population size is an important component of selection for sex, favoring segregation when deleterious alleles are nearly additive to dominant. Furthermore, sex tends to break correlations in homozygosity among selected loci, which disfavors sex when deleterious alleles are either recessive or dominant. As a result, we find that it is difficult to maintain costly sex when deleterious alleles are recessive. LOH tends to favor sex when deleterious mutations are recessive, but the effect is relatively weak for rates of LOH corresponding to current estimates (of the order 10(-4)-10(-5)).

  17. Deleterious Mutations and Selection for Sex in Finite Diploid Populations

    PubMed Central

    Roze, Denis; Michod, Richard E.

    2010-01-01

    In diploid populations, indirect benefits of sex may stem from segregation and recombination. Although it has been recognized that finite population size is an important component of selection for recombination, its effects on selection for segregation have been somewhat less studied. In this article, we develop analytical two- and three-locus models to study the effect of recurrent deleterious mutations on a modifier gene increasing sex, in a finite diploid population. The model also incorporates effects of mitotic recombination, causing loss of heterozygosity (LOH). Predictions are tested using multilocus simulations representing deleterious mutations occurring at a large number of loci. The model and simulations show that excess of heterozygosity generated by finite population size is an important component of selection for sex, favoring segregation when deleterious alleles are nearly additive to dominant. Furthermore, sex tends to break correlations in homozygosity among selected loci, which disfavors sex when deleterious alleles are either recessive or dominant. As a result, we find that it is difficult to maintain costly sex when deleterious alleles are recessive. LOH tends to favor sex when deleterious mutations are recessive, but the effect is relatively weak for rates of LOH corresponding to current estimates (of the order 10−4−10−5). PMID:20083613

  18. Deciphering the diploid ancestral genome of the Mesohexaploid Brassica rapa.

    PubMed

    Cheng, Feng; Mandáková, Terezie; Wu, Jian; Xie, Qi; Lysak, Martin A; Wang, Xiaowu

    2013-05-01

    The genus Brassica includes several important agricultural and horticultural crops. Their current genome structures were shaped by whole-genome triplication followed by extensive diploidization. The availability of several crucifer genome sequences, especially that of Chinese cabbage (Brassica rapa), enables study of the evolution of the mesohexaploid Brassica genomes from their diploid progenitors. We reconstructed three ancestral subgenomes of B. rapa (n = 10) by comparing its whole-genome sequence to ancestral and extant Brassicaceae genomes. All three B. rapa paleogenomes apparently consisted of seven chromosomes, similar to the ancestral translocation Proto-Calepineae Karyotype (tPCK; n = 7), which is the evolutionarily younger variant of the Proto-Calepineae Karyotype (n = 7). Based on comparative analysis of genome sequences or linkage maps of Brassica oleracea, Brassica nigra, radish (Raphanus sativus), and other closely related species, we propose a two-step merging of three tPCK-like genomes to form the hexaploid ancestor of the tribe Brassiceae with 42 chromosomes. Subsequent diversification of the Brassiceae was marked by extensive genome reshuffling and chromosome number reduction mediated by translocation events and followed by loss and/or inactivation of centromeres. Furthermore, via interspecies genome comparison, we refined intervals for seven of the genomic blocks of the Ancestral Crucifer Karyotype (n = 8), thus revising the key reference genome for evolutionary genomics of crucifers.

  19. Inheritance of dense spike in diploid wheat and Aegilops squarrosa.

    PubMed

    Goncharov, N P; Kondratenko, E Ya; Kawahara, T

    2002-01-01

    The individuals of diploid wheat Triticum boeoticum, T. monococcum and T. sinskajae and goatgrass Aegilops squarrosa were picked out with screening the dense spike characteristics. The dense-spike accessions were discovered in diploid wheat (T. sinskajae) and Ae. squarrosa. Inheritance of the dense spike was studied. The trait was found to be controlled by a recessive gene in T. sinskajae and by an incomplete dominant gene in Ae. squarrosa. The dosage effect of dominant gene C was detected in interspecific pentaploid F1 hybrid plants T. compactum x T. palmovae (2n =35, A(u)A(b)BDD genome). The spike of pentaploid hybrid was not so dense as compared to hexaploid wheat T. compactum. This is the first report showing similarity of the expression of dominant gene C on D genome of the hexaploid wheat to that of dense spike gene in Ae. squarrosa. The existence of dense-spike accessions of Ae. squarrosa allows us to hypothesize that the origin of T. compactum is independent from that of common wheat.

  20. Lycopene content, antioxidant capacity and colour attributes of selected watermelon (Citrullus lanatus (Thunb.) Mansfeld) cultivars grown in India.

    PubMed

    Nagal, Shweta; Kaur, Charanjit; Choudhary, Harshawardhan; Singh, Jashbir; Bhushan Singh, Braj; Singh, K N

    2012-12-01

    The present investigation reports variability in lycopene, ascorbic acid, total phenolics, antioxidant capacity and colour attributes of 12 watermelon cultivars grown in India. Antioxidant capacity was evaluated using four in vitro assays, namely ferric reducing antioxidant power, cupric reducing antioxidant capacity, Trolox equivalent antioxidant capacity and 2,2-diphenyl-1-picryl hydrazyl. Among watermelon cultivars, significant differences (p < 0.05) were found with respect to lycopene content and antioxidant capacity. Lycopene content ranged from 03.46 to 8.00 mg/100 g fresh weight. Colour of watermelon flesh was described by an optimized colour index (CI). Cultivars 'PWM25-4', 'Arun', 'Kiran' and 'Kareena' were found to be the most promising ones with highest lycopene content, antioxidant capacity and CI. Results indicate that watermelon is a good source of dietary lycopene and there exists significant variation that can be exploited to produce high-quality cultivars.

  1. Scanning genomic areas under selection sweep and association mapping as tools to identify horticultural important genes in watermelon

    USDA-ARS?s Scientific Manuscript database

    Watermelon (Citrullus lanatus var. lanatus) contains 88% water, sugars, and several important health-related compounds, including lycopene, citrulline, arginine, and glutathione. The current genetic diversity study uses microsatellites with known map positions to identify genomic regions that under...

  2. Diploid-triploid mosaicism and tissue ploidy diversity within Platemys platycephala from Suriname.

    PubMed

    Bickham, J W; Hanks, B G

    2009-01-01

    The twist-necked turtle, Platemys platycephala, is 1 of only 2 known species to possess sexual reproduction and diploid-triploid mosaicism. Previous studies have shown that mosaics occur in Suriname and French Guiana but only diploids are known from Bolivia and Brazil. In this paper, the frequency of ploidy mosaicism was studied in a large sample of P. platycephala from Suriname to more fully explore the diversity of ploidy levels within and among individuals. Flow-cytometric analysis of blood revealed a wide diversity of conditions including diploids, diploid-triploid mosaics, triploids, and triploid-tetraploid mosaics. The largest frequency class was 100% diploid, and the second largest was 100% triploid. However, mosaic individuals were observed from the entire spectrum of mixtures ranging from nearly all-diploid to nearly all-triploid and 2 individuals were triploid-tetraploid mosaics. It appears likely that diploids, triploids and mosaics do not represent distinct biotypes, but simply different conditions within a spectrum of possible ploidy mixtures. Studies of multiple tissues from 5 individuals showed blood alone is a good indicator of ploidy, but subtle differences were found among tissues for some individuals, and some individuals that were all-diploid or all-triploid in blood were found to be mosaic in other tissues. Triploidy was statistically associated with males, and we hypothesize that genome size plays a role in sex determination in this species.

  3. The development and phenotyping of diploid recombinant inbred lines of potato

    USDA-ARS?s Scientific Manuscript database

    Progress continues to be made in the effort to transform potato from a tetraploid outbreeding crop into a diploid inbreeding one. This transformation will ultimately lead to more efficient breeding and cultivar development. A variety of genetic resources will be required before a cultivated diploid ...

  4. Ribosomal RNA structure in the diploid and phylogenetically polyploid amphibian species Hyla and Odontophrynus.

    PubMed

    Leipoldt, M; Kellner, M

    1984-01-01

    Ribosomal RNA of the diploid amphibian species Hyla chrysoscelis and Odontophrynus americanus is structurally modified by hidden breaks. Phylogenetically polyploid related species like the tetraploid Hyla versicolor, the tetraploid Odontophrynus americanus and the octoploid Ceratophrys ornata do not show hidden breaks in ribosomal RNA. Structural modifications of rRNA molecules in diploid amphibians has no detectable effect on the ribosomal activity in vitro.

  5. Chemical reproductive traits of diploid Bombus terrestris males: Consequences on bumblebee conservation.

    PubMed

    Lecocq, Thomas; Gérard, Maxence; Maebe, Kevin; Brasero, Nicolas; Dehon, Lauren; Smagghe, Guy; Valterová, Irena; De Meulemeester, Thibaut; Rasmont, Pierre; Michez, Denis

    2016-03-07

    The current bumblebee decline leads to inbreeding in populations that fosters a loss of allelic diversity and diploid male production. As diploid males are viable and their offspring are sterile, bumblebee populations can quickly fall in a vortex of extinction. In this paper, we investigate for the first time a potential pre-mating mechanism through a major chemical reproductive trait (male cephalic labial gland secretions) that could prevent monandrous virgin queens from mating with diploid males. We focus our study on the cephalic labial gland secretions of diploid and haploid males of Bombus terrestris (L.). Contrary to initial expectations, our results do not show any significant differentiation of cephalic labial gland secretions between diploid and haploid specimens. Queens seem therefore to be unable to avoid mating with diploid males based on their compositions of cephalic labial gland secretions. This suggests that the vortex of extinction of diploid males could not be stopped through pre-mating avoidance based on the cephalic labial gland secretions but other mechanisms could avoid mating between diploid males and queens. This article is protected by copyright. All rights reserved.

  6. Karyotype characterization of Eurysternus caribaeus: the smallest diploid number among Scarabaeidae (Coleoptera: Scarabaeoidea).

    PubMed

    Cabral-de-Mello, Diogo Cavalcanti; Silva, Fernando Augusto Barbosa; de Cássia de Moura, Rita

    2007-01-01

    Eurysternus caribaeus was analyzed cytologically by conventional chromosomal staining. The species presents a diploid number of 2n=8, chromosomes with two arms and an XY sex determining mechanism. This is the first karyotype described for the genus Eurysternus and the tribe Eurysternini, and is also the smallest diploid number observed in the family Scarabaeidae and superfamily Scarabaeoidea.

  7. The Evolution of Vicia ramuliflora (Fabaceae) at Tetraploid and Diploid Levels Revealed with FISH and RAPD

    PubMed Central

    Han, Ying; Liu, Yuan; Wang, Haoyou; Liu, Xiangjun

    2017-01-01

    Vicia ramuliflora L. is a widely distributed species in Eurasia with high economic value. For past 200 years, it has evolved a tetraploid cytotype and new subspecies at the diploid level. Based on taxonomy, cytogeography and other lines of evidence, previous studies have provided valuable information about the evolution of V. ramuliflora ploidy level, but due to the limited resolution of traditional methods, important questions remain. In this study, fluorescence in situ hybridization (FISH) and random amplified polymorphic DNA (RAPD) were used to analyze the evolution of V. ramuliflora at the diploid and tetraploid levels. Our aim was to reveal the genomic constitution and parents of the tetraploid V. ramuliflora and the relationships among diploid V. ramuliflora populations. Our study showed that the tetraploid cytotype of V. ramuliflora at Changbai Mountains (M) has identical 18S and 5S rDNA distribution patterns with the diploid Hengdaohezi population (B) and the diploid Dailing population (H). However, UPGMA clustering, Neighbor-Joining clustering and principal coordinates analysis based on RAPD showed that the tetraploid cytotype (M) has more close relationships with Qianshan diploid population T. Based on our results and the fact that interspecific hybridization among Vicia species is very difficult, we think that the tetraploid V. ramuliflora is an autotetraploid and its genomic origin still needs further study. In addition, our study also found that Qianshan diploid population (T) had evolved distinct new traits compared with other diploid populations, which hints that V. ramuliflora evolved further at diploid level. We suggest that diploid population T be re-classified as a new subspecies. PMID:28135314

  8. Evolution of maternal care in diploid and haplodiploid populations.

    PubMed

    Gardner, A

    2012-08-01

    Maternal care has been suggested to evolve more readily in haplodiploid populations. Because maternal care appears to have been a prerequisite for the evolution of eusociality, this effect potentially explains the apparent preponderance of haplodiploidy among eusocial taxa. Here, I use a kin selection approach to model the evolution of maternal care in diploid and haplodiploid populations. In contrast to previous suggestions, I find that haplodiploidy may inhibit as well as promote the evolution of maternal care. Moreover, I find that the haplodiploidy effect vanishes in outbred populations if gene effects average rather than add together. I confirm these analytical results using numerical simulation of an explicit population genetics model. This analysis casts doubt upon the idea that haplodiploidy has promoted the evolution of maternal care and, consequently, the evolution of eusociality.

  9. Methionine restriction slows down senescence in human diploid fibroblasts.

    PubMed

    Kozieł, Rafał; Ruckenstuhl, Christoph; Albertini, Eva; Neuhaus, Michael; Netzberger, Christine; Bust, Maria; Madeo, Frank; Wiesner, Rudolf J; Jansen-Dürr, Pidder

    2014-12-01

    Methionine restriction (MetR) extends lifespan in animal models including rodents. Using human diploid fibroblasts (HDF), we report here that MetR significantly extends their replicative lifespan, thereby postponing cellular senescence. MetR significantly decreased activity of mitochondrial complex IV and diminished the accumulation of reactive oxygen species. Lifespan extension was accompanied by a significant decrease in the levels of subunits of mitochondrial complex IV, but also complex I, which was due to a decreased translation rate of several mtDNA-encoded subunits. Together, these findings indicate that MetR slows down aging in human cells by modulating mitochondrial protein synthesis and respiratory chain assembly. © 2014 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  10. Through-glass copper via using the glass reflow and seedless electroplating processes for wafer-level RF MEMS packaging

    NASA Astrophysics Data System (ADS)

    Lee, Ju-Yong; Lee, Sung-Woo; Lee, Seung-Ki; Park, Jae-Hyoung

    2013-08-01

    We present a novel method for the fabrication of void-free copper-filled through-glass-vias (TGVs), and their application to the wafer-level radio frequency microelectromechanical systems (RF MEMS) packaging scheme. By using the glass reflow process with a patterned silicon mold, a vertical TGV with smooth sidewall and fine pitch could be achieved. Bottom-up void-free filling of the TGV is successfully demonstrated through the seedless copper electroplating process. In addition, the proposed process allows wafer-level packaging with glass cap encapsulation using the anodic bonding process, since the reflowed glass interposer is only formed in the device area surrounded with silicon substrate. A simple coplanar waveguide (CPW) line was employed as the packaged device to evaluate the electrical characteristics and thermo-mechanical reliability of the proposed packaging structure. The fabricated packaging structure showed a low insertion loss of 0.116 dB and a high return loss of 35.537 dB at 20 GHz, which were measured through the whole electrical path, including the CPW line, TGVs and contact pads. An insertion loss lower than 0.1 dB and a return loss higher than 30 dB could be achieved at frequencies of up to 15 GHz, and the resistance of the single copper via was measured to be 36 mΩ. Furthermore, the thermo-mechanical reliability of the proposed packaging structure was also verified through thermal shock and pressure cooker test.

  11. Seedless Synthesis of Monodispersed Gold Nanorods with Remarkably High Yield: Synergistic Effect of Template Modification and Growth Kinetics Regulation.

    PubMed

    Liu, Kang; Bu, Yanru; Zheng, Yuanhui; Jiang, Xuchuan; Yu, Aibing; Wang, Huanting

    2017-03-08

    Gold nanorods (AuNRs) are versatile materials due to their broadly tunable optical properties associated with their anisotropic feature. Conventional seed-mediated synthesis is, however, not only limited by the operational complexity and over-sensitivity towards subtle changes of experimental conditions but also suffers from low yield (≈15 %). A facile seedless method is reported to overcome these challenges. Monodispersed AuNRs with high yield (≈100 %) and highly adjustable longitudinal surface plasmon resonance (LSPR) are reproducibly synthesized. The parameters that influence the AuNRs growth were thoroughly investigated in terms of growth kinetics and soft-template regulation, offering a better understanding of the template-based mechanism. The facile synthesis, broad tunability of LSRP, high reproducibility, high yield, and ease of scale-up make this method promising for the future mass production of monodispersed AuNRs for applications in catalysis, sensing, and biomedicine. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Seedless Polyol Synthesis and CO Oxidation Activity of Monodisperse (111) and (100)-Oriented Rhodium Nanocrystals in Sub-10 nm Sizes

    SciTech Connect

    Zhang, Yawen; Grass, Michael E.; Huang, Wenyu; Somorjai, Gabor A.

    2010-03-15

    Monodisperse sub-10 nm (6.5 nm) sized Rh nanocrystals with (111) and (100) surface structures were synthesized by a seedless polyol reduction in ethylene glycol, with poly(vinylpyrrolidone) as a capping ligand. When using [Rh(Ac){sub 2}]{sub 2} as the metal precursor, (111)-oriented Rh nanopolyhedra containing 76% (111)-twined hexagons (in 2D projection) were obtained; whereas, when employing RhCl{sub 3} as the metal precursor in the presence of alkylammonium bromide, such as tetramethylammonium bromide and trimethyl(tetradecyl)ammonium bromide, (100)-oriented Rh nanocubes were obtained with 85% selectivity. The {l_brace}100{r_brace} faces of the Rh nanocrystals are stabilized by chemically adsorbed Br{sup -} ions from alkylammonium bromides, which led to (100)-oriented nanocubes. Monolayer films of the (111)-oriented Rh nanopolyhedra and (100)-oriented Rh nanocubes were deposited on silicon wafers in a Langmuir-Blodgett trough to make model 2D nanoarray catalysts. These nanocatalysts were active for CO oxidation by O{sub 2}, and the turnover frequency was independent of nanoparticle shape, consistent with that previously observed for Rh(111) and Rh(100) single crystals.

  13. Effects of allelopathic compounds of corn pollen on respiration and cell division of watermelon.

    PubMed

    Cruz Ortega, R; Anaya, A L; Ramos, L

    1988-01-01

    The effects of the allelopathic compounds of an "'ethanolic extract" of corn pollen on growth, respiration, and cellular division of watermelon (Citrullus lanatus, var. peacock improved) were studied. Bioassays with the ethanolic extract showed an inhibition of radicle and hypocotyl growth. The effects on respiration were observed in isolated watermelon hypocotyl mitochondria. The ethanolic extract acts as an inhibitor of the electron pathway, decreasing oxygen consumption in state 3, with malate and succinate substrates. The specific inhibition site probably is located before the cytochromec. Ascorbate-TMPD as substrate reversed the inhibitory effect of the ethanolic extract. An evaluation of the mitotic index was made in slide preparations of previously treated meristematic cells. A decrease in mitotic activity of more than 50% was found, as well as irregular and pycnotic nuclei. The data obtained from this study reflect an important mechanism of action of the allelopathic compounds of corn pollen.

  14. The watermelon mitochondrial URF-1 gene: evidence for a complex structure.

    PubMed

    Stern, D B; Bang, A G; Thompson, W F

    1986-01-01

    We have cloned and sequenced a fragment of watermelon mitochondrial DNA (mtDNA) which contains a gene homologous to mitochondrial URF-1 (Unidentified Reading Frame-1) of vertebrates, Drosophila yakuba and Aspergillus nidulans. URF-1 is thought to encode a component of the respiratory chain NADH dehydrogenase. Two coding regions in the watermelon gene are separated by approximately 1,450 bp of untranslatable DNA. These two exons encode the central portions of URF-1, and are highly conserved. We postulate that three additional exons, selected by their map location and amino acid homology to other URF-1 sequences, encode the remainder of the polypeptide. This is the first description of a plant mitochondrial gene with multiple introns.

  15. Genetic Transformation of Watermelon with Pumpkin DNA by Low Energy Ion Beam-Mediated Introduction

    NASA Astrophysics Data System (ADS)

    Wang, Hao-bo; Gao, Xiu-wu; Guo, Jin-hua; Huang, Qun-ce; Yu, Zeng-liang

    2002-12-01

    The No.601 watermelon (citrullus lanatus) seeds were treated with 25 keV N+ implantation at the dosage of 7.8 × 1016 ions/cm2. After treatment, watermelon seeds were incubated with 380 μg/μl pumpkin (Cucubita, maxima Duch) DNA solution at 35 °C for 5 hours. By two-generations of selection and resistance screening at seedling stage, one transformed material was selected out, whose rind color is similar to that of the donor pumpkin and whose size of seeds is between that of the donor and the receptor. Using AFLP (amplified fragment length polymorphism) technique, two polymorphic DNA fragments were amplified. This primarily testified that the donor DNA fragments/gene were introduced into the receptor cell and integrated into the genomic DNA of the receptor.

  16. A metabolomics approach to identify and quantify the phytochemicals in watermelons by quantitative (1)HNMR.

    PubMed

    Jayaprakasha, G K; Patil, Bhimanagouda S

    2016-06-01

    Watermelon (Citrullus vulgaris) contains many health-promoting compounds, such as ascorbic acid, carotenoids, phenolic acids and amino acids including l-citrulline, arginine, and glutathione. Reported HPLC method for quantification of l-citrulline and sugars in watermelon involves, time-consuming sample preparation, post-column color development and detection with fluorescence and refractive index detectors. The present study describes development of a method to identify and quantify amino acids and sugars simultaneously from watermelon samples using quantitative proton NMR. Lyophilized watermelon samples (30-50mg) were extracted with deuterium oxide (D2O) by sonication and the centrifuged extract was directly used for quantification and identification with (1)HNMR. An external coaxial insert containing a 65µL of 0.012% 3-(trimethylsilyl) propionic-(2,2,3,3-d4) acid sodium salt (TSP-d4) in D2O was used as a quantitative reference. The levels of l-citrulline and sugars were measured in less than 6min. This rapid quantitation method was validated for specificity, linearity, accuracy, precision, reproducibility, and robustness. The limit of detection for l-citrulline was 38µg/mL and the limit of quantification was 71µg/mL; for sugars, the limits were 59-94µg/mL and 120µg/mL, respectively. This method can be used widely for confirmation and rapid quantitation of multiple compounds in large number of biological or breeding samples for routine analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Stability of fruit quality traits in diverse watermelon cultivars tested in multiple environments

    PubMed Central

    Dia, Mahendra; Wehner, Todd C; Perkins-Veazie, Penelope; Hassell, Richard; Price, Daniel S; Boyhan, George E; Olson, Stephen M; King, Stephen R; Davis, Angela R; Tolla, Gregory E; Bernier, Jerome; Juarez, Benito

    2016-01-01

    Lycopene is a naturally occurring red carotenoid compound that is found in watermelon. Lycopene has antioxidant properties. Lycopene content, sugar content and hollowheart resistance are subject to significant genotype×environment interaction (G×E), which makes breeding for these fruit quality traits difficult. The objectives of this study were to (i) evaluate the influence of years and locations on lycopene content, sugar content and hollowheart resistance for a set of watermelon genotypes, and (ii) identify genotypes with high stability for lycopene, sugar, and hollowheart resistance. A diverse set of 40 genotypes was tested over 3 years and 8 locations across the southern United States in replicated, multi-harvest trials. Lycopene was tested in a subset of 10 genotypes. Data were analyzed using univariate and multivariate stability statistics (BLUP-GGE biplot) using SASGxE and RGxE programs. There were strong effects of environment as well as G×E interaction on watermelon quality traits. On the basis of stability measures, genotypes were classified as stable or unstable for each quality trait. 'Crimson Sweet' is an inbred line with high quality trait performance as well as trait stability. 'Stone Mountain', 'Tom Watson', 'Crimson Sweet' and 'Minilee' were among the best genotypes for lycopene content, sugar content and hollowheart resistance. We developed a stability chart based on marketable yield and average ranking generated from different stability measures for yield attributes and quality traits. The chart will assist in choosing parents for improvement of watermelon cultivars. See http://cuke.hort.ncsu.edu/cucurbit/wmelon/wmelonmain.html. PMID:28066557

  18. Stability of fruit quality traits in diverse watermelon cultivars tested in multiple environments.

    PubMed

    Dia, Mahendra; Wehner, Todd C; Perkins-Veazie, Penelope; Hassell, Richard; Price, Daniel S; Boyhan, George E; Olson, Stephen M; King, Stephen R; Davis, Angela R; Tolla, Gregory E; Bernier, Jerome; Juarez, Benito

    2016-01-01

    Lycopene is a naturally occurring red carotenoid compound that is found in watermelon. Lycopene has antioxidant properties. Lycopene content, sugar content and hollowheart resistance are subject to significant genotype×environment interaction (G×E), which makes breeding for these fruit quality traits difficult. The objectives of this study were to (i) evaluate the influence of years and locations on lycopene content, sugar content and hollowheart resistance for a set of watermelon genotypes, and (ii) identify genotypes with high stability for lycopene, sugar, and hollowheart resistance. A diverse set of 40 genotypes was tested over 3 years and 8 locations across the southern United States in replicated, multi-harvest trials. Lycopene was tested in a subset of 10 genotypes. Data were analyzed using univariate and multivariate stability statistics (BLUP-GGE biplot) using SASGxE and RGxE programs. There were strong effects of environment as well as G×E interaction on watermelon quality traits. On the basis of stability measures, genotypes were classified as stable or unstable for each quality trait. 'Crimson Sweet' is an inbred line with high quality trait performance as well as trait stability. 'Stone Mountain', 'Tom Watson', 'Crimson Sweet' and 'Minilee' were among the best genotypes for lycopene content, sugar content and hollowheart resistance. We developed a stability chart based on marketable yield and average ranking generated from different stability measures for yield attributes and quality traits. The chart will assist in choosing parents for improvement of watermelon cultivars. See http://cuke.hort.ncsu.edu/cucurbit/wmelon/wmelonmain.html.

  19. 2n+n Hybridization of Apomictic Paspalum dilatatum with Diploid Paspalum Species.

    PubMed

    Espinoza; Quarín

    2000-03-01

    Common dallisgrass (Paspalum dilatatum) is an apomictic pentaploid (2n=5x=50) of hybrid origin with irregular meiosis and with the genome formula IIJJX. The I and J genomes are homologous to those of diploid P. intermedium and P. jurgensii, respectively, but the source of the X genome is unknown. Members of the X genome may have genes of special biological significance, including those controlling apomixis. Common dallisgrass was crossed with several diploid Paspalum species in an attempt to identify the source of the X genome. Since common dallisgrass is apomictic, all hybrids produced will be formed by fertilization of an unreduced egg (2n+n). Any hybrid showing 30 chromosome bivalents at meiosis would indicate that the male diploid parent has a chromosome set that is homologous to the X genome of dallisgrass. Over 36,000 spikelets of dallisgrass were emasculated and dusted with pollen of 15 different diploid species (diploid species bearing I or J genomes were excluded). Only five (P. chaseanum, P. equitans, P. fasciculatum, P. notatum, and P. simplex) produced 2n+n hybrids with P. dilatatum. Meiotic chromosome behavior was similar in all hexaploid hybrids showing ca. 20 bivalents and 20 univalents. Results indicated a very low rate of 2n+n hybridization; none of the five diploid species possessed the X genome. Because several diploid species failed to hybridize with 5x dallisgrass, other methods should be attempted. Molecular markers specific for the X genome may help solve the question.

  20. Identification of suitable reference genes for gene expression normalization in qRT-PCR analysis in watermelon.

    PubMed

    Kong, Qiusheng; Yuan, Jingxian; Gao, Lingyun; Zhao, Shuang; Jiang, Wei; Huang, Yuan; Bie, Zhilong

    2014-01-01

    Watermelon is one of the major Cucurbitaceae crops and the recent availability of genome sequence greatly facilitates the fundamental researches on it. Quantitative real-time reverse transcriptase PCR (qRT-PCR) is the preferred method for gene expression analyses, and using validated reference genes for normalization is crucial to ensure the accuracy of this method. However, a systematic validation of reference genes has not been conducted on watermelon. In this study, transcripts of 15 candidate reference genes were quantified in watermelon using qRT-PCR, and the stability of these genes was compared using geNorm and NormFinder. geNorm identified ClTUA and ClACT, ClEF1α and ClACT, and ClCAC and ClTUA as the best pairs of reference genes in watermelon organs and tissues under normal growth conditions, abiotic stress, and biotic stress, respectively. NormFinder identified ClYLS8, ClUBCP, and ClCAC as the best single reference genes under the above experimental conditions, respectively. ClYLS8 and ClPP2A were identified as the best reference genes across all samples. Two to nine reference genes were required for more reliable normalization depending on the experimental conditions. The widely used watermelon reference gene 18SrRNA was less stable than the other reference genes under the experimental conditions. Catalase family genes were identified in watermelon genome, and used to validate the reliability of the identified reference genes. ClCAT1and ClCAT2 were induced and upregulated in the first 24 h, whereas ClCAT3 was downregulated in the leaves under low temperature stress. However, the expression levels of these genes were significantly overestimated and misinterpreted when 18SrRNA was used as a reference gene. These results provide a good starting point for reference gene selection in qRT-PCR analyses involving watermelon.

  1. Identification of Suitable Reference Genes for Gene Expression Normalization in qRT-PCR Analysis in Watermelon

    PubMed Central

    Gao, Lingyun; Zhao, Shuang; Jiang, Wei; Huang, Yuan; Bie, Zhilong

    2014-01-01

    Watermelon is one of the major Cucurbitaceae crops and the recent availability of genome sequence greatly facilitates the fundamental researches on it. Quantitative real-time reverse transcriptase PCR (qRT–PCR) is the preferred method for gene expression analyses, and using validated reference genes for normalization is crucial to ensure the accuracy of this method. However, a systematic validation of reference genes has not been conducted on watermelon. In this study, transcripts of 15 candidate reference genes were quantified in watermelon using qRT–PCR, and the stability of these genes was compared using geNorm and NormFinder. geNorm identified ClTUA and ClACT, ClEF1α and ClACT, and ClCAC and ClTUA as the best pairs of reference genes in watermelon organs and tissues under normal growth conditions, abiotic stress, and biotic stress, respectively. NormFinder identified ClYLS8, ClUBCP, and ClCAC as the best single reference genes under the above experimental conditions, respectively. ClYLS8 and ClPP2A were identified as the best reference genes across all samples. Two to nine reference genes were required for more reliable normalization depending on the experimental conditions. The widely used watermelon reference gene 18SrRNA was less stable than the other reference genes under the experimental conditions. Catalase family genes were identified in watermelon genome, and used to validate the reliability of the identified reference genes. ClCAT1and ClCAT2 were induced and upregulated in the first 24 h, whereas ClCAT3 was downregulated in the leaves under low temperature stress. However, the expression levels of these genes were significantly overestimated and misinterpreted when 18SrRNA was used as a reference gene. These results provide a good starting point for reference gene selection in qRT–PCR analyses involving watermelon. PMID:24587403

  2. Influence of watermelon seed protein concentrates on dough handling, textural and sensory properties of cookies.

    PubMed

    Wani, Ali Abas; Sogi, D S; Singh, Preeti; Khatkar, B S

    2015-04-01

    Fruit processing wastes contain numerous by products of potential use in food & allied industry. Watermelon seeds represent a major by-product of the processing waste and contain high amount of nutritional proteins. Protein rich cereal based products are in demand due to their health promoting benefits. With this aim, wheat flour was fortified with watermelon seed protein concentrates (2.5 %, 5 %, 7.5 % and 10 % levels) to prepare cookies with desirable physical, nutritional, and textural and sensory properties. Substitution levels of 5 % and 10 % significantly (p ≤ 0.05) increased the dough stability and mixing tolerance index, however pasting properties and dough extensibility decreased considerably above 5 % substitution levels. Cookie fracture force (kg) increased significantly (p ≤ 0.05) above 5 % fortification levels. Cookie spread factor (W/T) increased from 2.5 % to 7.5 % fortification levels, further increase showed negative impact. Sensory scores of the cookies showed that protein concentrate may be added up to 7.5 % fortification levels. This study revealed that watermelon protein concentrates can be fortified with protein concentrates upto 5-7.5 % levels in cookies to improve their protein quality.

  3. Exogenous Melatonin Confers Salt Stress Tolerance to Watermelon by Improving Photosynthesis and Redox Homeostasis

    PubMed Central

    Li, Hao; Chang, Jingjing; Chen, Hejie; Wang, Zhongyuan; Gu, Xiurong; Wei, Chunhua; Zhang, Yong; Ma, Jianxiang; Yang, Jianqiang; Zhang, Xian

    2017-01-01

    Melatonin, a pleiotropic signal molecule, has been shown to play important roles in the regulation of plant growth, development, and responses to environmental stresses. Since a few species have been investigated to unveil the effect of exogenous melatonin on salt stress, the underlying mechanism of melatonin-mediated salt stress tolerance in other plant species still remains largely unknown. In this study, the effects of melatonin on leaf photosynthesis and redox homeostasis in watermelon were examined under salt stress (300 mM NaCl) along with different doses of melatonin (50, 150, and 500 μM) pretreatment. NaCl stress inhibited photosynthesis and increased accumulation of reactive oxygen species and membrane damage in leaves of watermelon seedlings. However, pretreatment with melatonin on roots alleviated NaCl-induced decrease in photosynthetic rate and oxidative stress in a dose-dependent manner. The protection of photosynthesis by melatonin was closely associated with the inhibition of stomatal closure and improved light energy absorption and electron transport in photosystem II, while the reduction of oxidative stress by melatonin was attributed to the improved redox homeostasis coupled with the enhanced activities of antioxidant enzymes. This study unraveled crucial role of melatonin in salt stress mitigation and thus can be implicated in the management of salinity in watermelon cultivation. PMID:28298921

  4. Purification and characterization of glutamate N-acetyltransferase involved in citrulline accumulation in wild watermelon.

    PubMed

    Takahara, Kentaro; Akashi, Kinya; Yokota, Akiho

    2005-10-01

    Citrulline is an efficient hydroxyl radical scavenger that can accumulate at concentrations of up to 30 mm in the leaves of wild watermelon during drought in the presence of strong light; however, the mechanism of this accumulation remains unclear. In this study, we characterized wild watermelon glutamate N-acetyltransferase (CLGAT) that catalyses the transacetylation reaction between acetylornithine and glutamate to form acetylglutamate and ornithine, thereby functioning in the first and fifth steps in citrulline biosynthesis. CLGAT enzyme purified 7000-fold from leaves was composed of two subunits with different N-terminal amino acid sequences. Analysis of the corresponding cDNA revealed that these two subunits have molecular masses of 21.3 and 23.5 kDa and are derived from a single precursor polypeptide, suggesting that the CLGAT precursor is cleaved autocatalytically at the conserved ATML motif, as in other glutamate N-acetyltransferases of microorganisms. A green fluorescence protein assay revealed that the first 26-amino acid sequence at the N-terminus of the precursor functions as a chloroplast transit peptide. The CLGAT exhibited thermostability up to 70 degrees C, suggesting an increase in enzyme activity under high leaf temperature conditions during drought/strong-light stresses. Moreover, CLGAT was not inhibited by citrulline or arginine at physiologically relevant high concentrations. These findings suggest that CLGAT can effectively participate in the biosynthesis of citrulline in wild watermelon leaves during drought/strong-light stress.

  5. Watermelon origin solved with molecular phylogenetics including Linnaean material: another example of museomics.

    PubMed

    Chomicki, Guillaume; Renner, Susanne S

    2015-01-01

    Type specimens are permanently preserved biological specimens that fix the usage of species names. This method became widespread from 1935 onwards and is now obligatory. We used DNA sequencing of types and more recent collections of wild and cultivated melons to reconstruct the evolutionary history of the genus Citrullus and the correct names for its species. We discovered that the type specimen of the name Citrullus lanatus, prepared by a Linnaean collector in South Africa in 1773, is not the species now thought of as watermelon. Instead, it is a representative of another species that is sister to C. ecirrhosus, a tendril-less South African endemic. The closest relative of the watermelon instead is a West African species. Our nuclear and plastid data furthermore reveal that there are seven species of Citrullus, not four as assumed. Our study implies that sweet watermelon originates from West, not southern Africa as previously believed, and that the South African citron melon has been independently domesticated. These findings affect and explain numerous studies on the origin of these two crops that led to contradictory results because of the erroneous merging of several distinct species.

  6. Exogenous Melatonin Confers Salt Stress Tolerance to Watermelon by Improving Photosynthesis and Redox Homeostasis.

    PubMed

    Li, Hao; Chang, Jingjing; Chen, Hejie; Wang, Zhongyuan; Gu, Xiurong; Wei, Chunhua; Zhang, Yong; Ma, Jianxiang; Yang, Jianqiang; Zhang, Xian

    2017-01-01

    Melatonin, a pleiotropic signal molecule, has been shown to play important roles in the regulation of plant growth, development, and responses to environmental stresses. Since a few species have been investigated to unveil the effect of exogenous melatonin on salt stress, the underlying mechanism of melatonin-mediated salt stress tolerance in other plant species still remains largely unknown. In this study, the effects of melatonin on leaf photosynthesis and redox homeostasis in watermelon were examined under salt stress (300 mM NaCl) along with different doses of melatonin (50, 150, and 500 μM) pretreatment. NaCl stress inhibited photosynthesis and increased accumulation of reactive oxygen species and membrane damage in leaves of watermelon seedlings. However, pretreatment with melatonin on roots alleviated NaCl-induced decrease in photosynthetic rate and oxidative stress in a dose-dependent manner. The protection of photosynthesis by melatonin was closely associated with the inhibition of stomatal closure and improved light energy absorption and electron transport in photosystem II, while the reduction of oxidative stress by melatonin was attributed to the improved redox homeostasis coupled with the enhanced activities of antioxidant enzymes. This study unraveled crucial role of melatonin in salt stress mitigation and thus can be implicated in the management of salinity in watermelon cultivation.

  7. Feasible sampling plan for Bemisia tabaci control decision-making in watermelon fields.

    PubMed

    Lima, Carlos Ho; Sarmento, Renato A; Pereira, Poliana S; Galdino, Tarcísio Vs; Santos, Fábio A; Silva, Joedna; Picanço, Marcelo C

    2017-11-01

    The silverleaf whitefly Bemisia tabaci is one of the most important pests of watermelon fields worldwide. Conventional sampling plans are the starting point for the generation of decision-making systems of integrated pest management programs. The aim of this study was to determine a conventional sampling plan for B. tabaci in watermelon fields. The optimal leaf for B. tabaci adult sampling was the 6(th) most apical leaf. Direct counting was the best pest sampling technique. Crop pest densities fitted the negative binomial distribution and had a common aggregation parameter (Kcommon ). The sampling plan consisted of evaluating 103 samples per plot. This sampling plan was conducted for 56 min, costing US$ 2.22 per sampling and with a 10% maximum evaluation error. The sampling plan determined in this study can be adopted by farmers because it enables the adequate evaluation of B. tabaci populations in watermelon fields (10% maximum evaluation error) and is a low-cost (US$ 2.22 per sampling), fast (56 min per sampling) and feasible (because it may be used in a standardized way throughout the crop cycle) technique. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  8. Phylogenetic relationship of ribosomal ITS2 and mitochondrial COI among diploid and triploid Paragonimus westermani isolates

    PubMed Central

    Im, Kyung-Il; Yong, Tai-Soon

    2003-01-01

    We compared patterns of intraspecific polymorphism of two markers with contrasting modes of evolution, nuclear ribosomal DNA (rDNA) and mitochondrial DNA (mtDNA), in the lung fluke, diploid and triploid Paragonimus westermani from three geographical regions of Korea. The genetic distances between three populations of Korean diploid and triploid P. westermani showed no significant difference in the nucleotide sequences of the mitochondrial cytochrome c oxidase subunit I (mtCOI) and ribosomaal second internal transcribed spacer (ITS2) genes. A highly resolved strict-consensus tree was obtained that illustrated phylogenetically useful information of the ITS2 and mtCOI sequences from diploid and triploid P. westermani. PMID:12666730

  9. Molecular epidemiology of clonal diploids: a quick overview and a short DIY (do it yourself) notice.

    PubMed

    De Meeûs, Thierry; Lehmann, Laurent; Balloux, François

    2006-03-01

    In this short review we report the basic notions needed for understanding the population genetics of clonal diploids. We focus on the consequences of clonality on the distribution of genetic diversity within individuals, between individuals and between populations. We then summarise how to detect clonality in mainly sexual populations, conversely, how to detect sexuality in mainly clonal populations and also how genetic differentiation between populations is affected by clonality in diploids. This information is then used for building recipes on how to analyse and interpret genetic polymorphism data in molecular epidemiology studies of clonal diploids.

  10. Unstable Diploids of Neurospora and a Model for Their Somatic Behavior

    PubMed Central

    Smith, David A.

    1974-01-01

    When ascospores from crosses of certain strains were germinated under conditions selective for heterozygosity of complementing markers on one linkage group, a portion of the resulting colonies were also heterozygous for unselected markers on other chromosomes, implying multiple disomy. The frequency of disomy and the pattern of marker homozygosity are consistent with most or all multiple disomics having originated as complete diploids following nondisjunction at meiosis I. The production of diploid ascospores in these strains is apparently under polygenic control. The diploids are highly unstable and do not differ from n+1 disomics in rates and mechanisms of haploidization and mitotic crossing over. PMID:4818264

  11. Embryo Localization Enhances the Survival of Acidovorax citrulli in Watermelon Seeds.

    PubMed

    Dutta, Bhabesh; Schneider, Raymond W; Robertson, Clark L; Walcott, Ronald R

    2016-04-01

    Acidovorax citrulli, the causal agent of bacterial fruit blotch (BFB) of cucurbits has been observed to survive for >34 years in stored melon and watermelon seeds. To better understand this remarkable longevity, we investigated the bacterium's tolerance to desiccation and the effect of bacterial localization in different watermelon seed tissues on its survival. We compared the ability of A. citrulli to tolerate desiccation on filter paper discs and on host (watermelon) and nonhost (cabbage, corn and tomato) seeds to two seedborne (Xanthomonas campestris pv. campestris and Pantoea stewartii subsp. stewartii) and one soilborne (Ralstonia solanacearum) plant-pathogenic bacteria. A. citrulli survival on dry filter paper (>12 weeks) was similar to that of X. campestris pv. campestris but longer than P. stewartii subsp. stewartii. Ralstonia solanacearum survived longer than all other bacteria tested. On all seeds tested, A. citrulli and X. campestris pv. campestris populations declined by 5 orders of magnitude after 12 weeks of incubation at 4°C and 50% relative humidity, while R. solanacearum populations declined by 3 orders. P. stewartii subsp. stewartii was not recovered after 12 weeks of incubation. To determine the effect of tissue localization on bacterial survival, watermelon seeds infested with A. citrulli by flower stigma inoculation (resulting in bacterial localization in the embryo/endosperm) or by ovary pericarp inoculations (resulting in bacterial localization under the testa) were treated with peroxyacetic acid or chlorine (Cl2) gas. Following these treatments, a significantly higher reduction in BFB seed-to-seedling transmission was observed for seeds generated by ovary pericarp inoculation (≥89.5%) than for those generated by stigma inoculation (≤76.5%) (P<0.05). Additionally, higher populations of A. citrulli survived when the bacteria were localized to the embryo/endosperm versus the seed coat, suggesting that tissue localization is important for

  12. Squash vein yellowing virus, causal agent of viral watermelon vine decline in Florida, USA – reservoirs, genome characterization and mixed infections

    USDA-ARS?s Scientific Manuscript database

    Squash vein yellowing virus (SqVYV) was identified in cucurbits in Florida in 2005, shown to be whitefly-transmissible and to induce a previously observed watermelon vine decline and fruit rind necrosis. SqVYV has been isolated from declining watermelons for the past six growing seasons in southwes...

  13. Genetic relationships in the desert watermelon citrullus colocynthis as viewed with high-frequency, oligonucleotide–targeting active gene (HFO–TAG) markers

    USDA-ARS?s Scientific Manuscript database

    U.S. Plant Introductions (PIs) of Citrullus colocynthis (L.) Schrad. are a viable source for enhancing disease and pest resistance in watermelon cultivars. However, there is information about their genetic diversity and relationships to watermelon cultivars. Genetic diversity and relationships were ...

  14. An integrated genetic linkage map of watermelon and genetic diversity based on single nucleotide polymorphism (SNP) and simple sequence repeat (SSR) markers

    USDA-ARS?s Scientific Manuscript database

    Watermelon (Citrullus lanatus var. lanatus) is an important vegetable fruit throughout the world. A high number of single nucleotide polymorphism (SNP) and simple sequence repeat (SSR) markers should provide large coverage of the watermelon genome and high phylogenetic resolution of germplasm acces...

  15. Carotenoid pigmentation affects the volatile composition of tomato and watermelon fruits, as revealed by comparative genetic analyses.

    PubMed

    Lewinsohn, Efraim; Sitrit, Yaron; Bar, Einat; Azulay, Yaniv; Meir, Ayala; Zamir, Dani; Tadmor, Yaakov

    2005-04-20

    Tomato near-isogenic lines differing in fruit carotenogenesis genes accumulated different aroma volatiles, in a strikingly similar fashion as compared to watermelon cultivars differing in fruit color. The major volatile norisoprenoids present in lycopene-containing tomatoes and watermelons were noncyclic, such as geranial, neral, 6-methyl-5-hepten-2-one, 2,6-dimethylhept-5-1-al, 2,3-epoxygeranial, (E,E)-pseudoionone, geranyl acetone, and farnesyl acetone, seemingly derived from lycopene and other noncyclic tetraterpenoids. Beta-ionone, dihydroactinodiolide, and beta-cyclocitral were prominent in both tomato and watermelon fruits containing beta-carotene. Alpha-ionone was detected only in an orange-fleshed tomato mutant that accumulates delta-carotene. A yellow flesh (r) mutant tomato bearing a nonfunctional psy1 gene and the yellow-fleshed watermelon Early Moonbeam, almost devoid of carotenoid fruit pigments, also lacked norisoprenoid derivatives and geranial. This study provides evidence, based on comparative genetics, that carotenoid pigmentation patterns have profound effects on the norisoprene and monoterpene aroma volatile compositions of tomato and watermelon and that in these fruits geranial (trans-citral) is apparently derived from lycopene in vivo.

  16. Watermelon (Citrullus lanatus (Thunb.) Matsum. and Nakai) juice modulates oxidative damage induced by low dose X-ray in mice.

    PubMed

    Mohammad, Mohd Khairul Amran; Mohamed, Muhamad Idham; Zakaria, Ainul Mardhiyah; Abdul Razak, Hairil Rashmizal; Saad, Wan Mazlina Md

    2014-01-01

    Watermelon is a natural product that contains high level of antioxidants and may prevent oxidative damage in tissues due to free radical generation following an exposure to ionizing radiation. The present study aimed to investigate the radioprotective effects of watermelon (Citrullus lanatus (Thunb.) Matsum. and Nakai) juice against oxidative damage induced by low dose X-ray exposure in mice. Twelve adult male ICR mice were randomly divided into two groups consisting of radiation (Rx) and supplementation (Tx) groups. Rx received filtered tap water, while Tx was supplemented with 50% (v/v) watermelon juice for 28 days ad libitum prior to total body irradiation by 100 μGy X-ray on day 29. Brain, lung, and liver tissues were assessed for the levels of malondialdehyde (MDA), apurinic/apyrimidinic (AP) sites, glutathione (GSH), and superoxide dismutase (SOD) inhibition activities. Results showed significant reduction of MDA levels and AP sites formation of Tx compared to Rx (P < 0.05). Mice supplemented with 50% watermelon juice restore the intracellular antioxidant activities by significantly increased SOD inhibition activities and GSH levels compared to Rx. These findings may postulate that supplementation of 50% watermelon (Citrullus lanatus (Thunb.) Matsum. and Nakai) juice could modulate oxidative damage induced by low dose X-ray exposure.

  17. Watermelon (Citrullus lanatus (Thunb.) Matsum. and Nakai) Juice Modulates Oxidative Damage Induced by Low Dose X-Ray in Mice

    PubMed Central

    Mohammad, Mohd Khairul Amran; Mohamed, Muhamad Idham; Abdul Razak, Hairil Rashmizal; Saad, Wan Mazlina Md.

    2014-01-01

    Watermelon is a natural product that contains high level of antioxidants and may prevent oxidative damage in tissues due to free radical generation following an exposure to ionizing radiation. The present study aimed to investigate the radioprotective effects of watermelon (Citrullus lanatus (Thunb.) Matsum. and Nakai) juice against oxidative damage induced by low dose X-ray exposure in mice. Twelve adult male ICR mice were randomly divided into two groups consisting of radiation (Rx) and supplementation (Tx) groups. Rx received filtered tap water, while Tx was supplemented with 50% (v/v) watermelon juice for 28 days ad libitum prior to total body irradiation by 100 μGy X-ray on day 29. Brain, lung, and liver tissues were assessed for the levels of malondialdehyde (MDA), apurinic/apyrimidinic (AP) sites, glutathione (GSH), and superoxide dismutase (SOD) inhibition activities. Results showed significant reduction of MDA levels and AP sites formation of Tx compared to Rx (P < 0.05). Mice supplemented with 50% watermelon juice restore the intracellular antioxidant activities by significantly increased SOD inhibition activities and GSH levels compared to Rx. These findings may postulate that supplementation of 50% watermelon (Citrullus lanatus (Thunb.) Matsum. and Nakai) juice could modulate oxidative damage induced by low dose X-ray exposure. PMID:24877107

  18. High-Resolution Genetic Map for Understanding the Effect of Genome-Wide Recombination Rate on Nucleotide Diversity in Watermelon

    PubMed Central

    Reddy, Umesh K.; Nimmakayala, Padma; Levi, Amnon; Abburi, Venkata Lakshmi; Saminathan, Thangasamy; Tomason, Yan. R.; Vajja, Gopinath; Reddy, Rishi; Abburi, Lavanya; Wehner, Todd C.; Ronin, Yefim; Karol, Abraham

    2014-01-01

    We used genotyping by sequencing to identify a set of 10,480 single nucleotide polymorphism (SNP) markers for constructing a high-resolution genetic map of 1096 cM for watermelon. We assessed the genome-wide variation in recombination rate (GWRR) across the map and found an association between GWRR and genome-wide nucleotide diversity. Collinearity between the map and the genome-wide reference sequence for watermelon was studied to identify inconsistency and chromosome rearrangements. We assessed genome-wide nucleotide diversity, linkage disequilibrium (LD), and selective sweep for wild, semi-wild, and domesticated accessions of Citrullus lanatus var. lanatus to track signals of domestication. Principal component analysis combined with chromosome-wide phylogenetic study based on 1563 SNPs obtained after LD pruning with minor allele frequency of 0.05 resolved the differences between semi-wild and wild accessions as well as relationships among worldwide sweet watermelon. Population structure analysis revealed predominant ancestries for wild, semi-wild, and domesticated watermelons as well as admixture of various ancestries that were important for domestication. Sliding window analysis of Tajima’s D across various chromosomes was used to resolve selective sweep. LD decay was estimated for various chromosomes. We identified a strong selective sweep on chromosome 3 consisting of important genes that might have had a role in sweet watermelon domestication. PMID:25227227

  19. Shared and divergent pathways for flower abscission are triggered by gibberellic acid and carbon starvation in seedless Vitis vinifera L.

    PubMed

    Domingos, Sara; Fino, Joana; Cardoso, Vânia; Sánchez, Claudia; Ramalho, José C; Larcher, Roberto; Paulo, Octávio S; Oliveira, Cristina M; Goulao, Luis F

    2016-02-01

    Abscission is a highly coordinated developmental process by which plants control vegetative and reproductive organs load. Aiming at get new insights on flower abscission regulation, changes in the global transcriptome, metabolome and physiology were analyzed in 'Thompson Seedless' grapevine (Vitis vinifera L.) inflorescences, using gibberellic acid (GAc) spraying and shading as abscission stimuli, applied at bloom. Natural flower drop rates increased from 63.1% in non-treated vines to 83% and 99% in response to GAc and shade treatments, respectively. Both treatments had a broad effect on inflorescences metabolism. Specific impacts from shade included photosynthesis inhibition, associated nutritional stress, carbon/nitrogen imbalance and cell division repression, whereas GAc spraying induced energetic metabolism simultaneously with induction of nucleotide biosynthesis and carbon metabolism, therefore, disclosing alternative mechanisms to regulate abscission. Regarding secondary metabolism, changes in flavonoid metabolism were the most represented metabolic pathways in the samples collected following GAc treatment while phenylpropanoid and stilbenoid related pathways were predominantly affected in the inflorescences by the shade treatment. However, both GAc and shade treated inflorescences revealed also shared pathways, that involved the regulation of putrescine catabolism, the repression of gibberellin biosynthesis, the induction of auxin biosynthesis and the activation of ethylene signaling pathways and antioxidant mechanisms, although often the quantitative changes occurred on specific transcripts and metabolites of the pathways. Globally, the results suggest that chemical and environmental cues induced contrasting effects on inflorescence metabolism, triggering flower abscission by different mechanisms and pinpointing the participation of novel abscission regulators. Grapevine showed to be considered a valid model to study molecular pathways of flower abscission

  20. KNOX2 genes regulate the haploid-to-diploid morphological transition in land plants.

    PubMed

    Sakakibara, Keiko; Ando, Sayuri; Yip, Hoichong Karen; Tamada, Yosuke; Hiwatashi, Yuji; Murata, Takashi; Deguchi, Hironori; Hasebe, Mitsuyasu; Bowman, John L

    2013-03-01

    Unlike animals, land plants undergo an alternation of generations, producing multicellular bodies in both haploid (1n: gametophyte) and diploid (2n: sporophyte) generations. Plant body plans in each generation are regulated by distinct developmental programs initiated at either meiosis or fertilization, respectively. In mosses, the haploid gametophyte generation is dominant, whereas in vascular plants-including ferns, gymnosperms, and angiosperms-the diploid sporophyte generation is dominant. Deletion of the class 2 KNOTTED1-LIKE HOMEOBOX (KNOX2) transcription factors in the moss Physcomitrella patens results in the development of gametophyte bodies from diploid embryos without meiosis. Thus, KNOX2 acts to prevent the haploid-specific body plan from developing in the diploid plant body, indicating a critical role for the evolution of KNOX2 in establishing an alternation of generations in land plants.

  1. Diploid and tetraploid grey treefrogs (Hyla chrysoscelis and Hyla versicolor) have similar metabolic rates.

    PubMed

    Kamel, S; Marsden, J E; Pough, F H

    1985-01-01

    We measured oxygen consumption of the diploid frog Hyla chrysoscelis and its recently evolved tetraploid cryptic species Hyla versicolor at rest and during forced locomotory exercise. We also measured whole-body lactic acid concentrations of individuals of the two species at rest and following 4 min of exercise. Contrary to predictions based on tissue-culture experiments, rates of organismal metabolism are not different in this diploid/tetraploid species pair: the diploid and tetraploid species did not differ in rates of oxygen consumption at rest or during exercise. Furthermore, whole-body lactate concentrations of frogs at rest and following forced locomotion were the same in the diploid and tetraploid species. For these species, polyploidy does not appear to be associated with lower maintenance costs at the level of the organism. However, polyploidy also does not appear to have metabolic consequences that would limit the behavioral or ecological repertoire of an anuran.

  2. Haematological parameters in Umbrina cirrosa (Teleostei, Sciaenidae): a comparison between diploid and triploid specimens.

    PubMed

    Ballarin, Loriano; Dall'Oro, Manuela; Bertotto, Daniela; Libertini, Angelo; Francescon, Antonia; Barbaro, Alvise

    2004-05-01

    Haematological features were compared between diploid and triploid specimens of the ray-finned fish Umbrina cirrosa. No significant differences between diploids and triploids were reported in haematocrit and total haemoglobin concentration, but erythrocytes and thrombocytes were significantly greater in size in triploids. Glycaemia was significantly lower in diploids, whereas triploid erythrocytes were more resistant to osmotic stress. In triploids, a greater fraction of leukocytes was positive for alkaline phosphatase activity, when stimulated with Bacillus clausii spores, otherwise no significant increase of oxygen consumption was observed in triploid leukocytes after stimulation, based on assays for superoxide anions. Triploids were characterized by a lower concentration of circulating blood cells with a lower surface/volume ratio when compared with diploids. These features may lead to a general disadvantage of triploids in withstanding stress conditions: a situation that needs to be taken into account in aquaculture practice.

  3. The population genetics of clonal and partially clonal diploids.

    PubMed Central

    Balloux, François; Lehmann, Laurent; de Meeûs, Thierry

    2003-01-01

    The consequences of variable rates of clonal reproduction on the population genetics of neutral markers are explored in diploid organisms within a subdivided population (island model). We use both analytical and stochastic simulation approaches. High rates of clonal reproduction will positively affect heterozygosity. As a consequence, nearly twice as many alleles per locus can be maintained and population differentiation estimated as F(ST) value is strongly decreased in purely clonal populations as compared to purely sexual ones. With increasing clonal reproduction, effective population size first slowly increases and then points toward extreme values when the reproductive system tends toward strict clonality. This reflects the fact that polymorphism is protected within individuals due to fixed heterozygosity. Contrarily, genotypic diversity smoothly decreases with increasing rates of clonal reproduction. Asexual populations thus maintain higher genetic diversity at each single locus but a lower number of different genotypes. Mixed clonal/sexual reproduction is nearly indistinguishable from strict sexual reproduction as long as the proportion of clonal reproduction is not strongly predominant for all quantities investigated, except for genotypic diversities (both at individual loci and over multiple loci). PMID:12930767

  4. Evolution of paternal care in diploid and haplodiploid populations.

    PubMed

    Davies, N G; Gardner, A

    2014-06-01

    W. D. Hamilton famously suggested that the inflated relatedness of full sisters under haplodiploidy explains why all workers in the social hymenoptera are female. This suggestion has not stood up to further theoretical scrutiny and is not empirically supported. Rather, it appears that altruistic sib-rearing in the social hymenoptera is performed exclusively by females because this behaviour has its origins in parental care, which was performed exclusively by females in the ancestors of this insect group. However, haplodiploidy might still explain the sex of workers if this mode of inheritance has itself been responsible for the rarity of paternal care in this group. Here, we perform a theoretical kin selection analysis to investigate the evolution of paternal care in diploid and haplodiploid populations. We find that haplodiploidy may either inhibit or promote paternal care depending on model assumptions, but that under the most plausible scenarios it promotes - rather than inhibits - paternal care. Our analysis casts further doubt upon there being a causal link between haplodiploidy and eusociality.

  5. Towards a unified genetic map for diploid roses.

    PubMed

    Spiller, Monika; Linde, Marcus; Hibrand-Saint Oyant, Laurence; Tsai, Ching-Jung; Byrne, David H; Smulders, Marinus J M; Foucher, Fabrice; Debener, Thomas

    2011-02-01

    We have constructed the first integrated consensus map (ICM) for rose, based on the information of four diploid populations and more than 1,000 initial markers. The single population maps are linked via 59 bridge markers, on average 8.4 per linkage group (LG). The integrated map comprises 597 markers, 206 of which are sequence-based, distributed over a length of 530 cM on seven LGs. By using a larger effective population size and therefore higher marker density, the marker order in the ICM is more reliable than in the single population maps. This is supported by a more even marker distribution and a decrease in gap sizes in the consensus map as compared to the single population maps. This unified map establishes a standard nomenclature for rose LGs, and presents the location of important ornamental traits, such as self-incompatibility, black spot resistance (Rdr1), scent production and recurrent blooming. In total, the consensus map includes locations for 10 phenotypic single loci, QTLs for 7 different traits and 51 ESTs or gene-based molecular markers. This consensus map combines for the first time the information for traits with high relevance for rose variety development. It will serve as a tool for selective breeding and marker assisted selection. It will benefit future efforts of the rose community to sequence the whole rose genome and will be useful for synteny studies in the Rosaceae family and especially in the section Rosoideae.

  6. Enhancer Runaway and the Evolution of Diploid Gene Expression

    PubMed Central

    Fyon, Frédéric; Cailleau, Aurélie; Lenormand, Thomas

    2015-01-01

    Evidence is mounting that the evolution of gene expression plays a major role in adaptation and speciation. Understanding the evolution of gene regulatory regions is indeed an essential step in linking genotypes and phenotypes and in understanding the molecular mechanisms underlying evolutionary change. The common view is that expression traits (protein folding, expression timing, tissue localization and concentration) are under natural selection at the individual level. Here, we use a theoretical approach to show that, in addition, in diploid organisms, enhancer strength (i.e., the ability of enhancers to activate transcription) may increase in a runaway process due to competition for expression between homologous enhancer alleles. These alleles may be viewed as self-promoting genetic elements, as they spread without conferring a benefit at the individual level. They gain a selective advantage by getting associated to better genetic backgrounds: deleterious mutations are more efficiently purged when linked to stronger enhancers. This process, which has been entirely overlooked so far, may help understand the observed overrepresentation of cis-acting regulatory changes in between-species phenotypic differences, and sheds a new light on investigating the contribution of gene expression evolution to adaptation. PMID:26561855

  7. Obstruction of adaptation in diploids by recessive, strongly deleterious alleles.

    PubMed

    Assaf, Zoe June; Petrov, Dmitri A; Blundell, Jamie R

    2015-05-19

    Recessive deleterious mutations are common, causing many genetic disorders in humans and producing inbreeding depression in the majority of sexually reproducing diploids. The abundance of recessive deleterious mutations in natural populations suggests they are likely to be present on a chromosome when a new adaptive mutation occurs, yet the dynamics of recessive deleterious hitchhikers and their impact on adaptation remains poorly understood. Here we model how a recessive deleterious mutation impacts the fate of a genetically linked dominant beneficial mutation. The frequency trajectory of the adaptive mutation in this case is dramatically altered and results in what we have termed a "staggered sweep." It is named for its three-phased trajectory: (i) Initially, the two linked mutations have a selective advantage while rare and will increase in frequency together, then (ii), at higher frequencies, the recessive hitchhiker is exposed to selection and can cause a balanced state via heterozygote advantage (the staggered phase), and (iii) finally, if recombination unlinks the two mutations, then the beneficial mutation can complete the sweep to fixation. Using both analytics and simulations, we show that strongly deleterious recessive mutations can substantially decrease the probability of fixation for nearby beneficial mutations, thus creating zones in the genome where adaptation is suppressed. These mutations can also significantly prolong the number of generations a beneficial mutation takes to sweep to fixation, and cause the genomic signature of selection to resemble that of soft or partial sweeps. We show that recessive deleterious variation could impact adaptation in humans and Drosophila.

  8. The legacy of diploid progenitors in allopolyploid gene expression patterns

    PubMed Central

    Buggs, Richard J. A.; Wendel, Jonathan F.; Doyle, Jeffrey J.; Soltis, Douglas E.; Soltis, Pamela S.; Coate, Jeremy E.

    2014-01-01

    Allopolyploidization (hybridization and whole-genome duplication) is a common phenomenon in plant evolution with immediate saltational effects on genome structure and gene expression. New technologies have allowed rapid progress over the past decade in our understanding of the consequences of allopolyploidy. A major question, raised by early pioneer of this field Leslie Gottlieb, concerned the extent to which gene expression differences among duplicate genes present in an allopolyploid are a legacy of expression differences that were already present in the progenitor diploid species. Addressing this question necessitates phylogenetically well-understood natural study systems, appropriate technology, availability of genomic resources and a suitable analytical framework, including a sufficiently detailed and generally accepted terminology. Here, we review these requirements and illustrate their application to a natural study system that Gottlieb worked on and recommended for this purpose: recent allopolyploids of Tragopogon (Asteraceae). We reanalyse recent data from this system within the conceptual framework of parental legacies on duplicate gene expression in allopolyploids. On a broader level, we highlight the intellectual connection between Gottlieb's phrasing of this issue and the more contemporary framework of cis- versus trans-regulation of duplicate gene expression in allopolyploid plants. PMID:24958927

  9. Species tree estimation of diploid Helianthus (Asteraceae) using target enrichment.

    PubMed

    Stephens, Jessica D; Rogers, Willie L; Mason, Chase M; Donovan, Lisa A; Malmberg, Russell L

    2015-06-01

    The sunflower genus Helianthus has long been recognized as economically significant, containing species of agricultural and horticultural importance. Additionally, this genus displays a large range of phenotypic and genetic variation, making Helianthus a useful system for studying evolutionary and ecological processes. Here we present the most robust Helianthus phylogeny to date, laying the foundation for future studies of this genus. We used a target enrichment approach across 37 diploid Helianthus species/subspecies with a total of 103 accessions. This technique garnered 170 genes used for both coalescent and concatenation analyses. The resulting phylogeny was additionally used to examine the evolution of life history and growth form across the genus. Coalescent and concatenation approaches were largely congruent, resolving a large annual clade and two large perennial clades. However, several relationships deeper within the phylogeny were more weakly supported and incongruent among analyses including the placement of H. agrestis, H. cusickii, H. gracilentus, H. mollis, and H. occidentalis. The current phylogeny supports three major clades including a large annual clade, a southeastern perennial clade, and another clade of primarily large-statured perennials. Relationships among taxa are more consistent with early phylogenies of the genus using morphological and crossing data than recent efforts using single genes, which highlight the difficulties of phylogenetic estimation in genera known for reticulate evolution. Additionally, conflict and low support at the base of the perennial clades may suggest a rapid radiation and/or ancient introgression within the genus. © 2015 Botanical Society of America, Inc.

  10. Genetic dissection of scent metabolic profiles in diploid rose populations.

    PubMed

    Spiller, M; Berger, R G; Debener, Thomas

    2010-05-01

    The scent of flowers is a very important trait in ornamental roses in terms of both quantity and quality. In cut roses, scented varieties are a rare exception. Although metabolic profiling has identified more than 500 scent volatiles from rose flowers so far, nothing is known about the inheritance of scent in roses. Therefore, we analysed scent volatiles and molecular markers in diploid segregating populations. We resolved the patterns of inheritance of three volatiles (nerol, neryl acetate and geranyl acetate) into single Mendelian traits, and we mapped these as single or oligogenic traits in the rose genome. Three other volatiles (geraniol, beta-citronellol and 2-phenylethanol) displayed quantitative variation in the progeny, and we mapped a total of six QTLs influencing the amounts of these volatiles onto the rose marker map. Because we included known scent related genes and newly generated ESTs for scent volatiles as markers, we were able to link scent related QTLs with putative candidate genes. Our results serve as a starting point for both more detailed analyses of complex scent biosynthetic pathways and the development of markers for marker-assisted breeding of scented rose varieties.

  11. The evolutionary advantage of haploid versus diploid microbes in nutrient-poor environments.

    PubMed

    Bessho, Kazuhiro; Iwasa, Yoh; Day, Troy

    2015-10-21

    Sexual eukaryotic organisms are characterized by haploid and diploid nuclear phases. In many organisms, growth and development occur in both haploid and diploid phases, and the relative length of these phases exhibits considerable diversity. A number of hypotheses have been put forward to explain the maintenance of this diversity of life cycles and the advantage of being haploid versus that of being diploid. The nutrient-limitation hypothesis postulates that haploid cells, because they are small and thus have a higher surface area to volume ratio, are advantageous in nutrient-poor environments. In this paper, we examine this hypothesis theoretically and determine the conditions under which it holds. On the basis of our analysis, we make the following predictions. First, the relative advantages of different ploidy levels strongly depend on the ploidy-dependent energy conversion efficiency and the scaling of mortality with cell size. Specifically, haploids enjoy a higher intrinsic population growth rate than diploids do under nutrient-poor conditions, but under nutrient-rich conditions the intrinsic population growth rate of diploids is higher, provided that the energy conversion efficiency of diploids is higher than that of haploids and the scaling of mortality with cell size is weak. Second, differences in nutrient concentration in the inflowing medium have almost no effect on the relative advantage of ploidy levels at population equilibrium. Our study illustrates the importance of explicit modeling of microbial life history and population dynamics to understand the evolution of ploidy levels.

  12. Somatic cell nuclear transfer: infinite reproduction of a unique diploid genome.

    PubMed

    Kishigami, Satoshi; Wakayama, Sayaka; Hosoi, Yoshihiko; Iritani, Akira; Wakayama, Teruhiko

    2008-06-10

    In mammals, a diploid genome of an individual following fertilization of an egg and a spermatozoon is unique and irreproducible. This implies that the generated unique diploid genome is doomed with the individual ending. Even as cultured cells from the individual, they cannot normally proliferate in perpetuity because of the "Hayflick limit". However, Dolly, the sheep cloned from an adult mammary gland cell, changes this scenario. Somatic cell nuclear transfer (SCNT) enables us to produce offspring without germ cells, that is, to "passage" a unique diploid genome. Animal cloning has also proven to be a powerful research tool for reprogramming in many mammals, notably mouse and cow. The mechanism underlying reprogramming, however, remains largely unknown and, animal cloning has been inefficient as a result. More momentously, in addition to abortion and fetal mortality, some cloned animals display possible premature aging phenotypes including early death and short telomere lengths. Under these inauspicious conditions, is it really possible for SCNT to preserve a diploid genome? Delightfully, in mouse and recently in primate, using SCNT we can produce nuclear transfer ES cells (ntES) more efficiently, which can preserve the eternal lifespan for the "passage" of a unique diploid genome. Further, new somatic cloning technique using histone-deacetylase inhibitors has been developed which can significantly increase the previous cloning rates two to six times. Here, we introduce SCNT and its value as a preservation tool for a diploid genome while reviewing aging of cloned animals on cellular and individual levels.

  13. Insights into the Evolution of Cotton Diploids and Polyploids from Whole-Genome Re-sequencing

    PubMed Central

    Page, Justin T.; Huynh, Mark D.; Liechty, Zach S.; Grupp, Kara; Stelly, David; Hulse, Amanda M.; Ashrafi, Hamid; Van Deynze, Allen; Wendel, Jonathan F.; Udall, Joshua A.

    2013-01-01

    Understanding the composition, evolution, and function of the Gossypium hirsutum (cotton) genome is complicated by the joint presence of two genomes in its nucleus (AT and DT genomes). These two genomes were derived from progenitor A-genome and D-genome diploids involved in ancestral allopolyploidization. To better understand the allopolyploid genome, we re-sequenced the genomes of extant diploid relatives that contain the A1 (Gossypium herbaceum), A2 (Gossypium arboreum), or D5 (Gossypium raimondii) genomes. We conducted a comparative analysis using deep re-sequencing of multiple accessions of each diploid species and identified 24 million SNPs between the A-diploid and D-diploid genomes. These analyses facilitated the construction of a robust index of conserved SNPs between the A-genomes and D-genomes at all detected polymorphic loci. This index is widely applicable for read mapping efforts of other diploid and allopolyploid Gossypium accessions. Further analysis also revealed locations of putative duplications and deletions in the A-genome relative to the D-genome reference sequence. The approximately 25,400 deleted regions included more than 50% deletion of 978 genes, including many involved with starch synthesis. In the polyploid genome, we also detected 1,472 conversion events between homoeologous chromosomes, including events that overlapped 113 genes. Continued characterization of the Gossypium genomes will further enhance our ability to manipulate fiber and agronomic production of cotton. PMID:23979935

  14. Tetraploid somatic hybrids of potato (Solanum tuberosum L.) obtained from diploid breeding lines.

    PubMed

    Przetakiewicz, Jarosław; Nadolska-Orczyk, Anna; Kuć, Dominik; Orczyk, Wacław

    2007-01-01

    Intraspecific somatic hybrids between 16 different diploid breeding lines of Solanum tuberosum L. were produced by PEG-induced fusion. Manually selected heterokaryons were cultured in a Millicells-CM using a post-fusion protoplast mixture. Plants were regenerated from calli derived from heterokaryons obtained from 10 out of 38 combinations of diploid lines. Of the tested putative somatic hybrids, 14.2% were diploid, 72.8% were tetraploid and 13% pentaploid. The DNA amplification pattern obtained with RAPD or semi-random primers confirmed that 6 fusion combinations were hybrids. In most cases, the morphological traits were intermediate to those of the diploid fusion partners. About 23.0% of the tested somatic hybrids showed variation in their morphology. Of the tested somatic hybrids, 78.0% flowered and 86.0% tuberized. The cytoplasm of 9 diploid lines and 6 somatic hybrid combinations was analysed. Two of the diploid lines had W/S chloroplasts and alpha or epsilon mitochondria; the remainder contained T chloroplasts and beta mitochondria. All the analysed somatic hybrids carried T chloroplasts and beta mitochondria.

  15. Somatic cell nuclear transfer: Infinite reproduction of a unique diploid genome

    SciTech Connect

    Kishigami, Satoshi Wakayama, Sayaka; Hosoi, Yoshihiko; Iritani, Akira; Wakayama, Teruhiko

    2008-06-10

    In mammals, a diploid genome of an individual following fertilization of an egg and a spermatozoon is unique and irreproducible. This implies that the generated unique diploid genome is doomed with the individual ending. Even as cultured cells from the individual, they cannot normally proliferate in perpetuity because of the 'Hayflick limit'. However, Dolly, the sheep cloned from an adult mammary gland cell, changes this scenario. Somatic cell nuclear transfer (SCNT) enables us to produce offspring without germ cells, that is, to 'passage' a unique diploid genome. Animal cloning has also proven to be a powerful research tool for reprogramming in many mammals, notably mouse and cow. The mechanism underlying reprogramming, however, remains largely unknown and, animal cloning has been inefficient as a result. More momentously, in addition to abortion and fetal mortality, some cloned animals display possible premature aging phenotypes including early death and short telomere lengths. Under these inauspicious conditions, is it really possible for SCNT to preserve a diploid genome? Delightfully, in mouse and recently in primate, using SCNT we can produce nuclear transfer ES cells (ntES) more efficiently, which can preserve the eternal lifespan for the 'passage' of a unique diploid genome. Further, new somatic cloning technique using histone-deacetylase inhibitors has been developed which can significantly increase the previous cloning rates two to six times. Here, we introduce SCNT and its value as a preservation tool for a diploid genome while reviewing aging of cloned animals on cellular and individual levels.

  16. Developing Seedless Growth of ZnO Micro/Nanowire Arrays towards ZnO/FeS2/CuI P-I-N Photodiode Application

    PubMed Central

    Yang, Zhi; Wang, Minqiang; Shukla, Sudhanshu; Zhu, Yue; Deng, Jianping; Ge, Hu; Wang, Xingzhi; Xiong, Qihua

    2015-01-01

    A seedless hydrothermal method is developed to grow high density and vertically aligned ZnO micro/nanowire arrays with low defect density on metal films under the saturated nutrition solution. In particular, the mechanism of seedless method is discussed here. A buffer layer can be confirmed by transmission electron microscopy (TEM), which may release the elastic strain between ZnO and substrate to achieve this highly mismatched heteroepitaxial structures. Based on ZnO micro/nanowire arrays with excellent wettability surface, we prepared ZnO-FeS2-CuI p-i-n photodiode by all-solution processed method with the high rectifying ratio of 197 at ±1 V. Under AM 1.5 condition, the Jsc of 0.5 mA/cm2, on-off current ratio of 371 and fast photoresponse at zero bias voltage were obtained. This good performance comes from excellent collection ability of photogenerated electrons and holes due to the increased depletion layer width for p-i-n structure. Finally, the high responsivity around 900 nm shows the potential as near infrared photodetectors applications. PMID:26077658

  17. Developing Seedless Growth of ZnO Micro/Nanowire Arrays towards ZnO/FeS2/CuI P-I-N Photodiode Application

    NASA Astrophysics Data System (ADS)

    Yang, Zhi; Wang, Minqiang; Shukla, Sudhanshu; Zhu, Yue; Deng, Jianping; Ge, Hu; Wang, Xingzhi; Xiong, Qihua

    2015-06-01

    A seedless hydrothermal method is developed to grow high density and vertically aligned ZnO micro/nanowire arrays with low defect density on metal films under the saturated nutrition solution. In particular, the mechanism of seedless method is discussed here. A buffer layer can be confirmed by transmission electron microscopy (TEM), which may release the elastic strain between ZnO and substrate to achieve this highly mismatched heteroepitaxial structures. Based on ZnO micro/nanowire arrays with excellent wettability surface, we prepared ZnO-FeS2-CuI p-i-n photodiode by all-solution processed method with the high rectifying ratio of 197 at ±1 V. Under AM 1.5 condition, the Jsc of 0.5 mA/cm2, on-off current ratio of 371 and fast photoresponse at zero bias voltage were obtained. This good performance comes from excellent collection ability of photogenerated electrons and holes due to the increased depletion layer width for p-i-n structure. Finally, the high responsivity around 900 nm shows the potential as near infrared photodetectors applications.

  18. Two weeks of watermelon juice supplementation improves nitric oxide bioavailability but not endurance exercise performance in humans.

    PubMed

    Bailey, Stephen J; Blackwell, Jamie R; Williams, Ewan; Vanhatalo, Anni; Wylie, Lee J; Winyard, Paul G; Jones, Andrew M

    2016-09-30

    This study tested the hypothesis that watermelon juice supplementation would improve nitric oxide bioavailability and exercise performance. Eight healthy recreationally-active adult males reported to the laboratory on two occasions for initial testing without dietary supplementation (control condition). Thereafter, participants were randomly assigned, in a cross-over experimental design, to receive 16 days of supplementation with 300 mL·day(-1) of a watermelon juice concentrate, which provided ∼3.4 g l-citrulline·day(-1) and an apple juice concentrate as a placebo. Participants reported to the laboratory on days 14 and 16 of supplementation to assess the effects of the interventions on blood pressure, plasma [l-citrulline], plasma [l-arginine], plasma [nitrite], muscle oxygenation and time-to-exhaustion during severe-intensity exercise. Compared to control and placebo, plasma [l-citrulline] (29 ± 4, 22 ± 6 and 101 ± 23 μM), [l-arginine] (74 ± 9, 67 ± 13 and 116 ± 9 μM) and [nitrite] (102 ± 29, 106 ± 21 and 201 ± 106 nM) were higher after watermelon juice supplementation (P < 0.01). However, systolic blood pressure was higher in the watermelon juice (130 ± 11) and placebo (131 ± 9) conditions compared to the control condition (124 ± 8 mmHg; P < 0.05). The skeletal muscle oxygenation index during moderate-intensity exercise was greater in the watermelon juice condition than the placebo and control conditions (P < 0.05), but time-to-exhaustion during the severe-intensity exercise test (control: 478 ± 80, placebo: 539 ± 108, watermelon juice: 550 ± 143 s) was not significantly different between conditions (P < 0.05). In conclusion, while watermelon juice supplementation increased baseline plasma [nitrite] and improved muscle oxygenation during moderate-intensity exercise, it increased resting blood pressure and did not improve time-to-exhaustion during severe-intensity exercise. These findings do not

  19. Obstruction of adaptation in diploids by recessive, strongly deleterious alleles

    PubMed Central

    Assaf, Zoe June; Petrov, Dmitri A.; Blundell, Jamie R.

    2015-01-01

    Recessive deleterious mutations are common, causing many genetic disorders in humans and producing inbreeding depression in the majority of sexually reproducing diploids. The abundance of recessive deleterious mutations in natural populations suggests they are likely to be present on a chromosome when a new adaptive mutation occurs, yet the dynamics of recessive deleterious hitchhikers and their impact on adaptation remains poorly understood. Here we model how a recessive deleterious mutation impacts the fate of a genetically linked dominant beneficial mutation. The frequency trajectory of the adaptive mutation in this case is dramatically altered and results in what we have termed a “staggered sweep.” It is named for its three-phased trajectory: (i) Initially, the two linked mutations have a selective advantage while rare and will increase in frequency together, then (ii), at higher frequencies, the recessive hitchhiker is exposed to selection and can cause a balanced state via heterozygote advantage (the staggered phase), and (iii) finally, if recombination unlinks the two mutations, then the beneficial mutation can complete the sweep to fixation. Using both analytics and simulations, we show that strongly deleterious recessive mutations can substantially decrease the probability of fixation for nearby beneficial mutations, thus creating zones in the genome where adaptation is suppressed. These mutations can also significantly prolong the number of generations a beneficial mutation takes to sweep to fixation, and cause the genomic signature of selection to resemble that of soft or partial sweeps. We show that recessive deleterious variation could impact adaptation in humans and Drosophila. PMID:25941393

  20. Vimentin is necessary for colony growth of human diploid keratinocytes.

    PubMed

    Castro-Muñozledo, Federico; Velez-DelValle, Cristina; Marsch-Moreno, Meytha; Hernández-Quintero, Miriam; Kuri-Harcuch, Walid

    2015-01-01

    The role of vimentin (Vim) in diploid epithelial cells is not well known. To understand its biological function, we cultured human epidermal keratinocytes under conditions that support migration, proliferation, stratification and terminal differentiation. We identified a keratinocyte subpopulation that shows a p63(+)/α5β1(bright) phenotype and displays Vim intermediate filaments (IFs) besides their keratin IF network. These cells were mainly located at the proliferative/migratory rim of the growing colonies; but also, they were scarce and scattered or formed small groups of basal cells in confluent stratified epithelia. Stimulation of cells with EGF and wounding experiments in confluent arrested epithelia increased the number of Vim(+) keratinocytes in an extent higher to the expected for a cell population doubling. BrdU labeling demonstrated that most of the proliferative cells located at the migratory border of the colony have Vim, in contrast with proliferative cells located at the basal layer at the center of big colonies which lacked of Vim IFs, suggesting that Vim expression was not solely linked to proliferation. Therefore, we silenced Vim mRNA in the cultured keratinocytes and observed an inhibition of colony growth. Such results, together with long-term cultivation assays which showed that Vim might be associated to pattern formation in cultured epithelia, suggest that Vim expression is essential for a highly motile phenotype, which is necessary for keratinocyte colony growth and possibly for development and wound healing. Vim(+)/p63(+)/α5β1(bright) epithelial cells may play a significant physiological role in embryonic morphogenetic movements; wound healing and other pathologies such as carcinomas and hyperproliferative diseases.

  1. Genetic mapping of QTLs controlling horticultural traits in diploid roses.

    PubMed

    Dugo, M L; Satovic, Z; Millán, T; Cubero, J I; Rubiales, D; Cabrera, A; Torres, A M

    2005-08-01

    A segregating progeny set of 96 F1 diploid hybrids (2n = 2x = 14) between "Blush Noisette" (D10), one of the first seedlings from the original "Champneys' Pink Cluster", and Rosa wichurana (E15), was used to construct a genetic linkage map of the rose genome following a "pseudo-testcross" mapping strategy. A total of 133 markers (130 RAPD, one morphological and two microsatellites) were located on the 14 linkage groups (LGs) of the D10 and E15 maps, covering total map lengths of 388 and 260 cM, respectively. Due to the presence of common biparental markers the homology of four LGs between parental maps (D10-1/E15-1 to D10-4/E15-4) could be inferred. Four horticulturally interesting quantitative traits, flower size (FS), days to flowering (DF), leaf size (LS), and resistance to powdery mildew (PM) were analysed in the progeny in order to map quantitative trait loci (QTLs) controlling these traits. A total of 13 putative QTLs (LOD > 3.0) were identified, four for FS, two for flowering time, five for LS, and two for resistance to PM. Possible homologies between QTLs detected in the D10 and E15 maps could be established between Fs1 and Fs3, Fs2 and Fs4, and Ls1 and Ls3. Screening for pairwise epistatic interactions between loci revealed additional, epistatic QTLs (EQTLs) for DF and LS that were not detected in the original QTL analysis. The genetic maps developed in this study will be useful to add new markers and locate genes for important traits in the genus providing a practical resource for marker-assisted selection programs in roses.

  2. Sex-determination system in the diploid yeast Zygosaccharomyces sapae.

    PubMed

    Solieri, Lisa; Dakal, Tikam Chand; Giudici, Paolo; Cassanelli, Stefano

    2014-06-17

    Sexual reproduction and breeding systems are driving forces for genetic diversity. The mating-type (MAT) locus represents a mutation and chromosome rearrangement hotspot in yeasts. Zygosaccharomyces rouxii complex yeasts are naturally faced with hostile low water activity (aw) environments and are characterized by gene copy number variation, genome instability, and aneuploidy/allodiploidy. Here, we investigated sex-determination system in Zygosaccharomyces sapae diploid strain ABT301(T), a member of the Z. rouxii complex. We cloned three divergent mating type-like (MTL) α-idiomorph sequences and designated them as ZsMTLα copies 1, 2, and 3. They encode homologs of Z. rouxii CBS 732(T) MATα2 (amino acid sequence identities spanning from 67.0 to 99.5%) and MATα1 (identity range 81.5-99.5%). ABT301(T) possesses two divergent HO genes encoding distinct endonucleases 100% and 92.3% identical to Z. rouxii HO. Cloning of MATA: -idiomorph resulted in a single ZsMTLA: locus encoding two Z. rouxii-like proteins MATA: 1 and MATA: 2. To assign the cloned ZsMTLα and ZsMTLA: idiomorphs as MAT, HML, and HMR cassettes, we analyzed their flanking regions. Three ZsMTLα loci exhibited the DIC1-MAT-SLA2 gene order canonical for MAT expression loci. Furthermore, four putative HML cassettes were identified, two containing the ZsMTLα copy 1 and the remaining harboring ZsMTLα copies 2 and 3. Finally, the ZsMTLA: locus was 3'-flanked by SLA2, suggesting the status of MAT expression locus. In conclusion, Z. sapae ABT301(T) displays an aααα genotype missing of the HMR silent cassette. Our results demonstrated that mating-type switching is a hypermutagenic process in Z. rouxii complex that generates genetic diversity de novo. This error-prone mechanism could be suitable to generate progenies more rapidly adaptable to hostile environments. Copyright © 2014 Solieri et al.

  3. Effect of high hydrostatic pressure on overall quality parameters of watermelon juice.

    PubMed

    Liu, Y; Zhao, X Y; Zou, L; Hu, X S

    2013-06-01

    High hydrostatic pressure as a kind of non-thermal processing might maintain the quality of thermo-sensitive watermelon juice. So, the effect of high hydrostatic pressure treatment on enzymes and quality of watermelon juice was investigated. After high hydrostatic pressure treatment, the activities of polyphenol oxidase, peroxidase, and pectin methylesterase of juice decreased significantly with the pressure (P < 0.05). Inactivation of polyphenol oxidase and peroxidase could be fitted by two-fraction model and that of pectin methylesterase could be described by first-order reaction model. Titratable acidity, pH, and total soluble solid of juice did not change significantly (P > 0.05). No significant difference was observed in lycopene and total phenolics after high hydrostatic pressure treatment when compared to the control (P > 0.05). Cloudiness and viscosity increased with pressure (P < 0.05) but did not change significantly with treatment time (P > 0.05). a*- and b*-value both unchanged after high hydrostatic pressure treatment (P > 0.05) while L*-value increased but the values had no significant difference among treated juices. Browning degree after high hydrostatic pressure treatment decreased with increase in pressure and treatment time (P < 0.05). Through the comparison of total color difference values, high hydrostatic pressure had little effect on color of juice. The results of this study demonstrated the efficacy of high hydrostatic pressure in inactivating enzymes and maintaining the quality of watermelon juice.

  4. The Ethylene Biosynthesis Gene CitACS4 Regulates Monoecy/Andromonoecy in Watermelon (Citrullus lanatus).

    PubMed

    Manzano, Susana; Aguado, Encarnación; Martínez, Cecilia; Megías, Zoraida; García, Alicia; Jamilena, Manuel

    2016-01-01

    Monoecious and andromonoecious cultivars of watermelon are characterised by the production of male and female flower or male and hermaphrodite flowers, respectively. The segregation analysis in the offspring of crosses between monoecious and andromonoecious lines has demonstrated that this trait is controlled by a single gene pair, being the monoecious allele M semi-dominant to the andromonoecious allele A. The two studied F1 hybrids (MA) had a predominantly monoecious phenotype since both produced not only female flowers, but also bisexual flowers with incomplete stamens, and hermaphrodite flowers with pollen. Given that in other cucurbit species andromonoecy is conferred by mutations in the ethylene biosynthesis genes CmACS7, CsACS2 and CpACS27A we have cloned and characterised CitACS4, the watermelon gene showing the highest similarity with the formers. CitACS4 encoded for a type ACS type III enzyme that is predominantly expressed in pistillate flowers of watermelon. In the andromonoecious line we have detected a missense mutation in a very conserved residue of CitACS4 (C364W) that cosegregates with the andromonoecious phenotype in two independent F2 populations, concomitantly with a reduction in ethylene production in the floral buds that will develop as hermaphrodite flowers. The gene does not however co-segregates with other sex expression traits regulated by ethylene in this species, including pistillate flowering transition and the number of pistillate flowers per plant. These data indicate that CitAC4 is likely to be involved in the biosynthesis of the ethylene required for stamen arrest during the development of female flowers. The C364W mutation would reduce the production of ethylene in pistillate floral buds, promoting the conversion of female into hermaphrodite flowers, and therefore of monoecy into andromonoecy.

  5. Pesticides residues in okra (non-target crop) grown close to a watermelon farm in Ghana.

    PubMed

    Essumang, D K; Asare, E A; Dodoo, D K

    2013-09-01

    The study looked at the levels of pesticides in okra grown close to a watermelon farm herein referred to as a non-target crop. The watermelon received some pesticide application in the course of its cultivation, and the okra which was not meant to be sprayed was also affected by the pesticide. About 500 okra samples were collected for a period of 6 weeks and pesticides extracted with 1:1 n-hexane and dichloromethane which was analysed with Agilent 2222 GC/MS coupled with 389 auto-sampler. The results confirmed accumulation of significant levels of pesticides in the non-target crop (okra grown close to watermelon farm). Levels of organochlorine pesticides ranged from 3.10 to 7.60 μg/kg whilst the organophosphorus pesticides had levels ranging from 2.80 to 2016.80 μg/kg. The synthetic pyrethroid pesticide mean levels also ranged from 0.10 to 4.10 μg/kg and were below World Health Organization/Food and Agriculture Organization-recommended residue levels, and though not appearing to constitute a grave threat to life, their occurrence is a concern, and pre-emptive techniques must be developed to thwart the contaminations. Though the non- target crop was not treated directly with the pesticides, some level of contamination with organochlorine and organophosphorus pesticides persisted in the crops. It can be inferred that application of pesticides affected the adjoining crops, meaning that inter-cropping and mix-cropping might not be acceptable when one of the crops requires pesticide application. It is important for the farmers to be trained to ensure proper application of pesticide to minimise its impact on the health of consumers.

  6. The Ethylene Biosynthesis Gene CitACS4 Regulates Monoecy/Andromonoecy in Watermelon (Citrullus lanatus)

    PubMed Central

    Manzano, Susana; Aguado, Encarnación; Martínez, Cecilia; Megías, Zoraida; García, Alicia; Jamilena, Manuel

    2016-01-01

    Monoecious and andromonoecious cultivars of watermelon are characterised by the production of male and female flower or male and hermaphrodite flowers, respectively. The segregation analysis in the offspring of crosses between monoecious and andromonoecious lines has demonstrated that this trait is controlled by a single gene pair, being the monoecious allele M semi-dominant to the andromonoecious allele A. The two studied F1 hybrids (MA) had a predominantly monoecious phenotype since both produced not only female flowers, but also bisexual flowers with incomplete stamens, and hermaphrodite flowers with pollen. Given that in other cucurbit species andromonoecy is conferred by mutations in the ethylene biosynthesis genes CmACS7, CsACS2 and CpACS27A we have cloned and characterised CitACS4, the watermelon gene showing the highest similarity with the formers. CitACS4 encoded for a type ACS type III enzyme that is predominantly expressed in pistillate flowers of watermelon. In the andromonoecious line we have detected a missense mutation in a very conserved residue of CitACS4 (C364W) that cosegregates with the andromonoecious phenotype in two independent F2 populations, concomitantly with a reduction in ethylene production in the floral buds that will develop as hermaphrodite flowers. The gene does not however co-segregates with other sex expression traits regulated by ethylene in this species, including pistillate flowering transition and the number of pistillate flowers per plant. These data indicate that CitAC4 is likely to be involved in the biosynthesis of the ethylene required for stamen arrest during the development of female flowers. The C364W mutation would reduce the production of ethylene in pistillate floral buds, promoting the conversion of female into hermaphrodite flowers, and therefore of monoecy into andromonoecy. PMID:27149159

  7. Generation of transgenic watermelon resistant to Zucchini yellow mosaic virus and Papaya ringspot virus type W.

    PubMed

    Yu, Tsong-Ann; Chiang, Chu-Hui; Wu, Hui-Wen; Li, Chin-Mei; Yang, Ching-Fu; Chen, Jun-Han; Chen, Yu-Wen; Yeh, Shyi-Dong

    2011-03-01

    Zucchini yellow mosaic virus (ZYMV) and Papaya ringspot virus type W (PRSV W) are major limiting factors for production of watermelon worldwide. For the effective control of these two viruses by transgenic resistance, an untranslatable chimeric construct containing truncated ZYMV coat protein (CP) and PRSV W CP genes was transferred to commercial watermelon cultivars by Agrobacterium-mediated transformation. Using our protocol, a total of 27 putative transgenic lines were obtained from three cultivars of 'Feeling' (23 lines), 'China baby' (3 lines), and 'Quality' (1 line). PCR and Southern blot analyses confirmed that the chimeric construct was incorporated into the genomic DNA of the transformants. Greenhouse evaluation of the selected ten transgenic lines of 'Feeling' cultivar revealed that two immune lines conferred complete resistance to ZYMV and PRSV W, from which virus accumulation were not detected by Western blotting 4 weeks after inoculation. The transgenic transcript was not detected, but small interfering RNA (siRNA) was readily detected from the two immune lines and T(1) progeny of line ZW 10 before inoculation, indicating that RNA-mediated post-transcriptional gene silencing (PTGS) is the underlying mechanism for the double-virus resistance. The segregation ratio of T(1) progeny of the immune line ZW10 indicated that the single inserted transgene is nuclearly inherited and associated with the phenotype of double-virus resistance as a dominant trait. The transgenic lines derived from the commercial watermelon cultivars have great potential for control of the two important viruses and can be implemented directly without further breeding.

  8. Watermelon-like iron nanoparticles: Cr doping effect on magnetism and magnetization interaction reversal

    SciTech Connect

    Kaur, Maninder; Dai, Qilin; Bowden, Mark E.; Engelhard, Mark H.; Wu, Yaqiao; Tang, Jinke; Qiang, You

    2013-06-26

    Chromium (Cr) forms a solid solution with iron (Fe) lattice when doped in core-shell iron -iron oxide nanocluster (NC) and shows a mixed phase of sigma (σ) FeCr and bcc Fe. The Cr dopant affects heavily the magnetization and magnetic reversal process, and causes the hysteresis loop to shrink near the zero field axis. Dramatic transformation happens from dipolar interaction (0 at. % Cr) to strong exchange interaction (8 at. % of Cr) is confirmed from the Henkel plot and delta M plot, and is explained by a water-melon model of core-shell NC system.

  9. Cytotype distribution at a diploid-hexaploid contact zone in Aster amellus (Asteraceae).

    PubMed

    Castro, S; Loureiro, J; Procházka, T; Münzbergová, Z

    2012-10-01

    The present study aims to assess the diversity and distribution of cytotypes of Aster amellus in central and eastern Europe, contributing with data to improve understanding of the evolutionary dynamics of the contact zone between diploids and hexaploids of this polyploid complex. Large-scale cytotype screening of 4720 individuals collected in 229 populations was performed using 4',6-diamidino-2-phenylindole (DAPI) flow cytometry. Fine-scale cytotype screening was performed in the mixed-ploidy population. Reproductive variables, such as number of florets per flower head, seed set and seedling emergence, as well as ploidy level of seeds and seedlings were recorded in this population. The diploid-hexaploid contact zone is large and complex, reaching the Czech Republic in the west, Austria in the south, Poland in the north-east and Romania in the extreme east of the surveyed areas. Most populations presented only one cytotype, either diploid or hexaploid. In several areas of the contact zone both cytotypes were found to grow in parapatry. One mixed-ploidy population of diploids and hexaploids was detected for the first time, but no signs of hybridization were detected. In this population, diploids had a significantly lower reproductive success, and significantly higher production of intercytotype offspring, being in reproductive disadvantage in comparison with hexaploids. The contact zone of diploid and hexaploid A. amellus in central and eastern Europe seems to be highly dynamic and diffuse, with both primary and secondary contacts being possible. The obtained results suggest the origin of hexaploids through diploids, overall supporting previous hypotheses that this species is autopolyploid. Data from the only mixed-ploidy population detected so far suggest that the minority cytotype exclusion is an important evolutionary mechanisms driving the prevalence of single-cytotype populations, and thus contributing to the current distributional patterns of the cytotypes of A

  10. Triploid Production from Interspecific Crosses of Two Diploid Perennial Helianthus with Diploid Cultivated Sunflower (Helianthus annuus L.)

    PubMed Central

    Liu, Zhao; Seiler, Gerald J.; Gulya, Thomas J.; Feng, Jiuhuan; Rashid, Khalid Y.; Cai, Xiwen; Jan, Chao-Chien

    2017-01-01

    Wild Helianthus species are a valuable genetic resource for the improvement of cultivated sunflower. We report the discovery and characterization of a unique high frequency production of triploids when cultivated sunflower was pollinated by specific accessions of diploid Helianthus nuttallii T. & G. and H. maximiliani Schr. Genomic in situ hybridization (GISH) analyses indicated that the triploid F1s had two genomes from the wild pollen sources and one from the cultivated line. Mitotic chromosome analyses indicated that the frequency of triploid progenies from the crosses of cultivated lines × H. nuttallii accession 102 (N102) was significantly higher than those of unexpected polyploid progenies from the crosses of wild perennial species × N102, and no unexpected polyploids were obtained from the reverse crosses. Pollen stainability analysis suggested the existence of a low percentage of unreduced (2n) male gametes in some accessions, especially N102 and H. maximiliani accession 1113 (M1113), which were generated at the telophase II and tetrad stages of meiosis. The triploid F1s could be the results of preferred fertilization of the low frequency of 2n male gametes with the female gametes of the cultivated sunflower, due to the dosage factors related to recognition and rejection of foreign pollen during fertilization. The triploids have been used to produce amphiploids and aneuploids. Future studies of the male gametes’ fate from pollination through fertilization will further uncover the mechanism of this whole genome transmission. Studies of the genetic control of this trait will facilitate research on sunflower polyploidy speciation and evolution, and the utilization of this trait in sunflower breeding. PMID:28179393

  11. Triploid Production from Interspecific Crosses of Two Diploid Perennial Helianthus with Diploid Cultivated Sunflower (Helianthus annuus L.).

    PubMed

    Liu, Zhao; Seiler, Gerald J; Gulya, Thomas J; Feng, Jiuhuan; Rashid, Khalid Y; Cai, Xiwen; Jan, Chao-Chien

    2017-02-07

    Wild Helianthus species are a valuable genetic resource for the improvement of cultivated sunflower. We report the discovery and characterization of a unique high frequency production of triploids when cultivated sunflower was pollinated by specific accessions of diploid Helianthus nuttallii T. &. G. and H. maximiliani Schr. Genomic in situ hybridization (GISH) analyses indicated that the triploid F1s had two genomes from the wild pollen sources and one from the cultivated line. Mitotic chromosome analyses indicated that the frequency of triploid progenies from the crosses of cultivated lines × H. nuttallii accession 102 (N102) was significantly higher than those of unexpected polyploid progenies from the crosses of wild perennial species × N102, and no unexpected polyploids were obtained from the reverse crosses. Pollen stainability analysis suggested the existence of a low percentage of unreduced (2n) male gametes in some accessions, especially N102 and H. maximiliani accession 1113 (M1113), which were generated at the telophase II and tetrad stages of meiosis. The triploid F1s could be the results of preferred fertilization of the low frequency of 2n male gametes with the female gametes of the cultivated sunflower, due to the dosage factors related to recognition and rejection of foreign pollen during fertilization. The triploids have been used to produce amphiploids and aneuploids. Future studies of the male gametes' fate from pollination through fertilization will further uncover the mechanism of this whole genome transmission. Studies of the genetic control of this trait will facilitate research on sunflower polyploidy speciation and evolution, and the utilization of this trait in sunflower breeding.

  12. The effect of D123 wheat as a companion crop on soil enzyme activities, microbial biomass and microbial communities in the rhizosphere of watermelon

    PubMed Central

    Xu, Weihui; Wang, Zhigang; Wu, Fengzhi

    2015-01-01

    The growth of watermelon is often threatened by Fusarium oxysporum f. sp. niveum (Fon) in successively monocultured soil, which results in economic loss. The objective of this study was to investigate the effect of D123 wheat as a companion crop on soil enzyme activities, microbial biomass and microbial communities in the rhizosphere of watermelon and to explore the relationship between the effect and the incidence of wilt caused by Fon. The results showed that the activities of soil polyphenol oxidase, urease and invertase were increased, the microbial biomass nitrogen (MBN) and microbial biomass phosphorus (MBP) were significantly increased, and the ratio of MBC/MBN was decreased (P < 0.05). Real-time PCR analysis showed that the Fon population declined significantly in the watermelon/wheat companion system compared with the monoculture system (P < 0.05). The analysis of microbial communities showed that the relative abundance of microbial communities was changed in the rhizosphere of watermelon. Compared with the monoculture system, the relative abundances of Alphaproteobacteria, Actinobacteria, Gemmatimonadetes and Sordariomycetes were increased, and the relative abundances of Gammaproteobacteria, Sphingobacteria, Cytophagia, Pezizomycetes, and Eurotiomycetes were decreased in the rhizosphere of watermelon in the watermelon/wheat companion system; importantly, the incidence of Fusarium wilt was also decreased in the watermelon/wheat companion system. In conclusion, this study indicated that D123 wheat as a companion crop increased soil enzyme activities and microbial biomass, decreased the Fon population, and changed the relative abundance of microbial communities in the rhizosphere of watermelon, which may be related to the reduction of Fusarium wilt in the watermelon/wheat companion system. PMID:26388851

  13. Microcollinearity between autopolyploid sugarcane and diploid sorghum genomes

    PubMed Central

    2010-01-01

    Background Sugarcane (Saccharum spp.) has become an increasingly important crop for its leading role in biofuel production. The high sugar content species S. officinarum is an octoploid without known diploid or tetraploid progenitors. Commercial sugarcane cultivars are hybrids between S. officinarum and wild species S. spontaneum with ploidy at ~12×. The complex autopolyploid sugarcane genome has not been characterized at the DNA sequence level. Results The microsynteny between sugarcane and sorghum was assessed by comparing 454 pyrosequences of 20 sugarcane bacterial artificial chromosomes (BACs) with sorghum sequences. These 20 BACs were selected by hybridization of 1961 single copy sorghum overgo probes to the sugarcane BAC library with one sugarcane BAC corresponding to each of the 20 sorghum chromosome arms. The genic regions of the sugarcane BACs shared an average of 95.2% sequence identity with sorghum, and the sorghum genome was used as a template to order sequence contigs covering 78.2% of the 20 BAC sequences. About 53.1% of the sugarcane BAC sequences are aligned with sorghum sequence. The unaligned regions contain non-coding and repetitive sequences. Within the aligned sequences, 209 genes were annotated in sugarcane and 202 in sorghum. Seventeen genes appeared to be sugarcane-specific and all validated by sugarcane ESTs, while 12 appeared sorghum-specific but only one validated by sorghum ESTs. Twelve of the 17 sugarcane-specific genes have no match in the non-redundant protein database in GenBank, perhaps encoding proteins for sugarcane-specific processes. The sorghum orthologous regions appeared to have expanded relative to sugarcane, mostly by the increase of retrotransposons. Conclusions The sugarcane and sorghum genomes are mostly collinear in the genic regions, and the sorghum genome can be used as a template for assembling much of the genic DNA of the autopolyploid sugarcane genome. The comparable gene density between sugarcane BACs and

  14. Aminoguanidine delays the replicative senescence of human diploid fibroblasts.

    PubMed

    Wang, Pei-chang; Zhang, Jian; Zhang, Zong-yu; Tong, Tan-jun

    2007-11-20

    The accumulation of free radicals and advanced glycation end products (AGEs) in cell plays a very important role in replicative senescence. Aminoguanidine (AG) has potential antioxidant effects and decreases AGE levels. This study aimed to investigate its effect on replicative senescence in vitro. The effects of aminoguanidine on morphology, replicative lifespan, cell growth and proliferation, AGEs, DNA damage, DNA repair ability and telomere length were observed in human fetal lung diploid fibroblasts (2BS). Aminoguanidine maintained the non-senescent phenotype of 2BS cells even at late population doubling (PD) and increased cumulative population doublings by at least 17 - 21 PDs. Aminoguanidine also improved the potentials of growth and proliferation of 2BS cells as detected by the MTT assay. The AGE levels of late PD cells grown from early PD in DMEM containing aminiguanidine decreased significantly compared with those of late PD control cells and were similar to those of young control cells. In addition, the cells pretreated with aminoguanidine had a significant reduction in DNA strand breaks when they were exposed to 200 micromol/L H(2)O(2) for 5 minutes which indicated that the compound had a strong potential to protect genomic DNA against oxidative stress. And most of the cells exposed to 100 micromol/L H(2)O(2) had much shorter comet tails and smaller tail areas after incubation with aminoguanidine-supplemented DMEM, which indicated that the compound strongly improved the DNA repair abilities of 2BS cells. Moreover, PD55 cells grown from PD28 in 2 mmol/L or 4 mmol/L aminoguanidine retain telomere lengths of 7.94 kb or 8.12 kb, which was 0.83 kb or 1.11 kb longer than that of the control cells. Aminoguanidine delays replicative senescence of 2BS cells and the senescence-delaying effect of aminoguanidine appear to be due to its many biological properties including its potential for proliferation improvement, its inhibitory effect of AGE formation, antioxidant

  15. Sex-Determination System in the Diploid Yeast Zygosaccharomyces sapae

    PubMed Central

    Solieri, Lisa; Dakal, Tikam Chand; Giudici, Paolo; Cassanelli, Stefano

    2014-01-01

    Sexual reproduction and breeding systems are driving forces for genetic diversity. The mating-type (MAT) locus represents a mutation and chromosome rearrangement hotspot in yeasts. Zygosaccharomyces rouxii complex yeasts are naturally faced with hostile low water activity (aw) environments and are characterized by gene copy number variation, genome instability, and aneuploidy/allodiploidy. Here, we investigated sex-determination system in Zygosaccharomyces sapae diploid strain ABT301T, a member of the Z. rouxii complex. We cloned three divergent mating type-like (MTL) α-idiomorph sequences and designated them as ZsMTLα copies 1, 2, and 3. They encode homologs of Z. rouxii CBS 732T MATα2 (amino acid sequence identities spanning from 67.0 to 99.5%) and MATα1 (identity range 81.5–99.5%). ABT301T possesses two divergent HO genes encoding distinct endonucleases 100% and 92.3% identical to Z. rouxii HO. Cloning of MATa-idiomorph resulted in a single ZsMTLa locus encoding two Z. rouxii-like proteins MATa1 and MATa2. To assign the cloned ZsMTLα and ZsMTLa idiomorphs as MAT, HML, and HMR cassettes, we analyzed their flanking regions. Three ZsMTLα loci exhibited the DIC1-MAT-SLA2 gene order canonical for MAT expression loci. Furthermore, four putative HML cassettes were identified, two containing the ZsMTLα copy 1 and the remaining harboring ZsMTLα copies 2 and 3. Finally, the ZsMTLa locus was 3′-flanked by SLA2, suggesting the status of MAT expression locus. In conclusion, Z. sapae ABT301T displays an aααα genotype missing of the HMR silent cassette. Our results demonstrated that mating-type switching is a hypermutagenic process in Z. rouxii complex that generates genetic diversity de novo. This error-prone mechanism could be suitable to generate progenies more rapidly adaptable to hostile environments. PMID:24939186

  16. Fasciola hepatica from naturally infected sheep and cattle in Great Britain are diploid.

    PubMed

    Beesley, N J; Cwiklinski, K; Williams, D J L; Hodgkinson, J

    2015-08-01

    Diploid (2n = 2x = 20) and triploid (2n = 3x = 30) Fasciola hepatica have been reported in the UK, and in Asia diploid, triploid and mixoploid (2x/3x) Fasciola spp. exist but there is little information to indicate how common triploidy is, particularly in UK fluke. Here the ploidy of 565 adult F. hepatica from 66 naturally infected British sheep and 150 adult F. hepatica from 35 naturally infected British cattle was determined. All 715 of these parasites were diploid, based on observation of 10 bivalent chromosomes and sperm (n = 335) or, since triploids are aspermic, sperm alone (n = 380). This constitutes the first extensive analysis of the ploidy of F. hepatica field isolates from Great Britain and shows that most F. hepatica isolated from cattle and sheep are diploid and have the capacity to sexually reproduce. These data suggest that triploidy, and by extension parthenogenesis, is rare or non-existent in wild British F. hepatica populations. Given that F. hepatica is the only species of Fasciola present in Britain our results indicate that the parasite is predominantly diploid in areas where F. hepatica exists in isolation and suggests that triploidy may only originate in natural populations where co-infection of F. hepatica and its sister species Fasciola gigantica commonly occurs.

  17. Comparison of Leaf Proteomes of Cassava (Manihot esculenta Crantz) Cultivar NZ199 Diploid and Autotetraploid Genotypes

    PubMed Central

    An, Feifei; Fan, Jie; Li, Jun; Li, Qing X.; Li, Kaimian; Zhu, Wenli; Wen, Feng; Carvalho, Luiz J. C. B.; Chen, Songbi

    2014-01-01

    Cassava polyploid breeding has drastically improved our knowledge on increasing root yield and its significant tolerance to stresses. In polyploid cassava plants, increases in DNA content highly affect cell volumes and anatomical structures. However, the mechanism of this effect is poorly understood. The purpose of the present study was to compare and validate the changes between cassava cultivar NZ199 diploid and autotetraploid at proteomic levels. The results showed that leaf proteome of cassava cultivar NZ199 diploid was clearly differentiated from its autotetraploid genotype using 2-DE combined MS technique. Sixty-five differential protein spots were seen in 2-DE image of autotetraploid genotype in comparison with that of diploid. Fifty-two proteins were identified by MALDI-TOF-MS/MS, of which 47 were up-regulated and 5 were down-regulated in autotetraploid genotype compared with diploid genotype. The classified functions of 32 up-regulated proteins were associated with photosynthesis, defense system, hydrocyanic acid (HCN) metabolism, protein biosynthesis, chaperones, amino acid metabolism and signal transduction. The remarkable variation in photosynthetic activity, HCN content and resistance to salt stress between diploid and autotetraploid genotypes is closely linked with expression levels of proteomic profiles. The analysis of protein interaction networks indicated there are direct interactions between the 15 up-regulation proteins involved in the pathways described above. This work provides an insight into understanding the protein regulation mechanism of cassava polyploid genotype, and gives a clue to improve cassava polyploidy breeding in increasing photosynthesis and resistance efficiencies. PMID:24727655

  18. Inhibitor and temperature effect on catalase in the liver of adult diploid and haploid Rana rugosa.

    PubMed

    Kashiwagi, A; Kashiwagi, K; Takase, M; Hanada, H; Yamashita, M; Naitoh, T; Nakamura, M

    1998-01-01

    The authors succeeded in raising a single mature haploid Rana rugosa female to the age of 2 years from an egg artificially fertilized with ultraviolet-irradiated sperm. In order to discover why this particular haploid individual should survive so long, hydrogen peroxide detoxifying catalase in the liver of this individual and age-matched diploids was examined and compared for total activity, temperature stability, and chemical inhibition. Total activity was found to be significantly higher in the haploid frog than in the diploids, suggesting that this particular haploid had a unique system for hydrogen peroxide detoxification which protected the liver against cell death, preventing hepatic failure, and leading to a prolonged survival. Liver catalase from the haploid proved to be more labile to aminotriazole and urea, losing 60-70% of its original activity after 30 min treatment, whereas diploid catalase lost only 40% under the same conditions. Haploid and diploid catalase responded similarly to heat, however. It seems likely that inhibitor-binding sites differ considerably between the catalase of normal diploids and the catalase of this particular haploid, while overall structure is generally similar.

  19. Comparative analysis of inbred and hybrid maize at the diploid and tetraploid levels.

    PubMed

    Riddle, Nicole C; Birchler, James A

    2008-02-01

    Heterosis often occurs in offspring derived from a cross between inbred or divergent parents and can be observed as the superior performance of these hybrids for a wide variety of characters. Heterosis was compared in maize lines at two ploidy levels, diploid and tetraploid, to gain a better understanding of the interaction of heterosis and ploidy level. Employing genetically identical diploid and tetraploid maize derived from four different inbred lines, we investigated heterosis for 11 morphological traits, including several plant height measures, as well as flowering time for both silks and anthers. We find that the heterotic response of a certain hybrid differs between diploid and tetraploid lines, and that the response at one ploidy cannot serve as a predictor for the other. Also, progressive heterosis was found for several of the characters in the tetraploid double-cross hybrid, which can have four different alleles at one locus, compared to the double-cross diploid hybrids, which can only possess two alleles per locus. Overall, the results indicate that the heterotic response of tetraploid maize lines differs significantly from that of the diploid.

  20. Cytophotometric and biochemical analyses of DNA in pentaploid and diploid Agave species.

    PubMed

    Cavallini, A; Natali, L; Cionini, G; Castorena-Sanchez, I

    1996-04-01

    Nuclear DNA content, chromatin structure, and DNA composition were investigated in four Agave species: two diploid, Agave tequilana Weber and Agave angustifolia Haworth var. marginata Hort., and two pentaploid, Agave fourcroydes Lemaire and Agave sisalana Perrine. It was determined that the genome size of pentaploid species is nearly 2.5 times that of diploid ones. Cytophotometric analyses of chromatin structure were performed following Feulgen or DAPI staining to determine optical density profiles of interphase nuclei. Pentaploid species showed higher frequencies of condensed chromatin (heterochromatin) than diploid species. On the other hand, a lower frequency of A-T rich (DAPI stained) heterochromatin was found in pentaploid species than in diploid ones, indicating that heterochromatin in pentaploid species is made up of sequences with base compositions different from those of diploid species. Since thermal denaturation profiles of extracted DNA showed minor variations in the base composition of the genomes of the four species, it is supposed that, in pentaploid species, the large heterochromatin content is not due to an overrepresentation of G-C repetitive sequences but rather to the condensation of nonrepetitive sequences, such as, for example, redundant gene copies switched off in the polyploid complement. It is suggested that speciation in the genus Agave occurs through point mutations and minor DNA rearrangements, as is also indicated by the relative stability of the karyotype of this genus. Key words : Agave, DNA cytophotometry, DNA melting profiles, chromatin structure, genome size.

  1. Comparison of leaf proteomes of cassava (Manihot esculenta Crantz) cultivar NZ199 diploid and autotetraploid genotypes.

    PubMed

    An, Feifei; Fan, Jie; Li, Jun; Li, Qing X; Li, Kaimian; Zhu, Wenli; Wen, Feng; Carvalho, Luiz J C B; Chen, Songbi

    2014-01-01

    Cassava polyploid breeding has drastically improved our knowledge on increasing root yield and its significant tolerance to stresses. In polyploid cassava plants, increases in DNA content highly affect cell volumes and anatomical structures. However, the mechanism of this effect is poorly understood. The purpose of the present study was to compare and validate the changes between cassava cultivar NZ199 diploid and autotetraploid at proteomic levels. The results showed that leaf proteome of cassava cultivar NZ199 diploid was clearly differentiated from its autotetraploid genotype using 2-DE combined MS technique. Sixty-five differential protein spots were seen in 2-DE image of autotetraploid genotype in comparison with that of diploid. Fifty-two proteins were identified by MALDI-TOF-MS/MS, of which 47 were up-regulated and 5 were down-regulated in autotetraploid genotype compared with diploid genotype. The classified functions of 32 up-regulated proteins were associated with photosynthesis, defense system, hydrocyanic acid (HCN) metabolism, protein biosynthesis, chaperones, amino acid metabolism and signal transduction. The remarkable variation in photosynthetic activity, HCN content and resistance to salt stress between diploid and autotetraploid genotypes is closely linked with expression levels of proteomic profiles. The analysis of protein interaction networks indicated there are direct interactions between the 15 up-regulation proteins involved in the pathways described above. This work provides an insight into understanding the protein regulation mechanism of cassava polyploid genotype, and gives a clue to improve cassava polyploidy breeding in increasing photosynthesis and resistance efficiencies.

  2. Establishment of a transgenic hairy root system in wild and domesticated watermelon (Citrullus lanatus) for studying root vigor under drought.

    PubMed

    Kajikawa, Masataka; Morikawa, Kaoru; Abe, Yosuke; Yokota, Akiho; Akashi, Kinya

    2010-07-01

    Root vigor is an important trait for the growth of terrestrial plants, especially in water-deficit environments. Although deserts plants are known for their highly developed root architecture, the molecular mechanism responsible for this trait has not been determined. Here we established an efficient protocol for the genetic manipulation of two varieties of watermelon plants: a desert-grown wild watermelon that shows vigorous root growth under drought, and a domesticated cultivar showing retardation of root growth under drought stress. Agrobacterium rhizogenes-mediated transgenic hairy roots were efficiently induced and selected from the hypocotyls of these plants. Transgenic GUS expression was detected in the roots by RT-PCR and histochemical GUS staining. Moreover, a liquid culture system for evaluating their root growth was also established. Interestingly, growth of the hairy roots derived from domesticated variety of watermelon strongly inhibited under high osmotic condition, whereas the hairy roots derived from wild variety of watermelon retained substantial growth rates under the stress condition. The new protocol presented here offers a powerful tool for the comparative study of the molecular mechanism underlying drought-induced root growth in desert plants.

  3. Markers Linked to the ZYMV-FL Resistance Gene and Their Use in Marker-assisted Selection in Watermelon

    USDA-ARS?s Scientific Manuscript database

    Zucchini yellow mosaic virus (ZYMV) is a major pathogen that reduces yield in cucurbits. The best studied strains include ZYMV-FL and ZYMV-CH of which resistance is conferred by a single recessive gene. Bulk segregate analysis was used for watermelon populations derived from PI 595203, a line with...

  4. Fungicide rotation schemes for managing Phytophthora fruit rot of watermelon across Southeastern United States (NC, SC, and GA)

    USDA-ARS?s Scientific Manuscript database

    Phytophthora capsici has been documented as a pathogen on a wide variety of vegetable crops in the family Solanaceae, Cucurbitaceae, Fabaceae, and plants belonging to 23 other families. Phytophthora fruit rot of watermelons caused by P. capsici is particularly severe in southeastern U.S where optima...

  5. Survival and growth populations of Salmonella transferred from melon rind surfaces to cantaloupe, honeydew, and watermelon pulps during preparation

    USDA-ARS?s Scientific Manuscript database

    Consumers are eating more fresh vegetable and fruit due to nutritional and health-related benefits. Whole melons (cantaloupes, honeydew and watermelons) are of particular interest because of their nutrient contents. However, they are frequently contaminated with foodborne pathogens. Conditions neces...

  6. Pre- and post-harvest development of Phytophthora fruit rot on watermelons treated with fungicides in the field

    USDA-ARS?s Scientific Manuscript database

    Fruit rot, caused by Phytophthora capsici, is a serious disease in most watermelon producing regions in southeastern U.S., and has caused devastating loss over the past few years. In many instances, severe losses occurred after harvest during transportation. Experiments were conducted in 2010, 201...

  7. Detection and occurrence of Melon yellow spot virus in Ecuador: an emergent threat to melon and watermelon production

    USDA-ARS?s Scientific Manuscript database

    Worldwide, more than fifty viruses have been reported in cucurbit crops. In Ecuador, approximately 3000 Ha of watermelon, melon and cucumbers are cultivated annually. However, very few studies have been conducted to identify viruses responsible for important epidemics in this crop in Ecuador. During...

  8. Effect of processing parameters on fouling resistances during microfiltration of red plum and watermelon juices: a comparative study.

    PubMed

    Nourbakhsh, Himan; Alemi, Azam; Emam-Djomeh, Zahra; Mirsaeedghazi, Hossein

    2014-01-01

    This study evaluated the total (R t ), reversible (R rev ), irreversible (R irr ), and cake (R c ) resistances during microfiltration of watermelon juice (as a juice with colloid particles) and red plum juice (as a juice without colloid particles). Results showed that the total resistance decreased by about 45% when the feed velocity was increased during clarification of red plum juice due to change in cake resistance. Also, increasing the feed temperature from 20 to 30°C decreased the total fouling resistance by about 9% due to decreases in the irreversible and reversible fouling resistances. Also, mixed cellulose ester (MCE) membrane (which is hydrophilic) had a lower cake resistance compared to polyvinylidene fluoride (PVDF) membrane (which is hydrophobic). Examination of the microfiltration of watermelon juice showed that R t decreased by about 54% when the feed temperature was increased from 20 to 50°C, partially due to the reduction of reversible fouling resistance by 78%. Also, increasing transmembrane pressures from 0.5 to 2.5 bars greatly increased total fouling resistance. The feed velocity had a different effect on fouling resistances during microfiltration of watermelon juice compared to red plum juice: in contrast with red plum juice, increasing the feed velocity for watermelon juice increased cake resistance.

  9. Novel Pseudomonas syringae strains associated with leaf spot diseases on watermelon (Citrullus lanatus) and squash (Cucurbita pepo) in California

    USDA-ARS?s Scientific Manuscript database

    In 2006 and 2011, bacteria, fluorescent on KMB, were isolated from leaf spots of greenhouse-grown watermelon (Citrullus lanatus) and field-grown squash (Cucurbita pepo) in coastal California. Biochemical characterization of the isolates indicated that they belonged to Pseudomonas syringae. Multilocu...

  10. Assessment of DAPG-producing Pseudomonas fluorescens for management of Meloidogyne incognita and Fusarium oxysporum on watermelon

    USDA-ARS?s Scientific Manuscript database

    Pseudomonas fluorescens isolates Clinto 1R, Wayne 1R and Wood 1R, which produce the antibiotic 2,4-diacetylphloroglucinol (DAPG), can suppress soilborne diseases and promote plant growth. Consequently, these beneficial bacterial isolates were tested on watermelon plants for suppression of Meloidogy...

  11. Involvement of ethylene in sex expression and female flower development in watermelon (Citrullus lanatus).

    PubMed

    Manzano, Susana; Martínez, Cecilia; García, Juan Manuel; Megías, Zoraida; Jamilena, Manuel

    2014-12-01

    Although it is known that ethylene has a masculinizing effect on watermelon, the specific role of this hormone in sex expression and flower development has not been analyzed in depth. By using different approaches the present work demonstrates that ethylene regulates differentially two sex-related developmental processes: sexual expression, i.e. the earliness and the number of female flowers per plant, and the development of individual floral buds. Ethylene production in the shoot apex as well as in male, female and bisexual flowers demonstrated that the female flower requires much more ethylene than the male one to develop, and that bisexual flowers result from a decrease in ethylene production in the female floral bud. The occurrence of bisexual flowers was found to be associated with elevated temperatures in the greenhouse, concomitantly with a reduction of ethylene production in the shoot apex. External treatments with ethephon and AVG, and the use of Cucurbita rootstocks with different ethylene production and sensitivity, confirmed that, as occurs in other cucurbit species, ethylene is required to arrest the development of stamens in the female flower. Nevertheless, in watermelon ethylene inhibits the transition from male to female flowering and reduces the number of pistillate flowers per plant, which runs contrary to findings in other cucurbit species. The use of Cucurbita rootstocks with elevated ethylene production delayed the production of female flowers but reduced the number of bisexual flowers, which is associated with a reduced fruit set and altered fruit shape.

  12. Evolution of watermelon fruit physicochemical and phytochemical composition during ripening as affected by grafting.

    PubMed

    Soteriou, G A; Kyriacou, M C; Siomos, A S; Gerasopoulos, D

    2014-12-15

    Flesh reflectance colorimetry, mechanical texture analysis, pH, titratable acidity (TA), and soluble solid (SS), soluble carbohydrate, lycopene and citrulline content of watermelon fruit were assessed throughout ripening (30-50 days post-anthesis; dpa) in grafted and self-rooted plants. Grafting increased firmness, TA, and lycopene content though it delayed its peak. Lycopene content was mostly ripening-dependant, highly correlated and synchronous with changes in pulp chroma (C) and colour a. The sweetness was affected only by ripening. However, total sugars and SS peaked later in fruit of grafted plants than in non-grafted ones, and significant interaction of ripening with grafting was observed. Citrulline content increased with ripening in fruit of grafted plants, reaching a peak at 45 dpa; whereas in non-grafted ones it was unchanged between 30 and 45 dpa and declined at 50 dpa. As ripening overall was retarded by grafting, fruit quality of grafted watermelon may benefit from belated harvest. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Complete Nucleotide Sequence of Watermelon Chlorotic Stunt Virus Originating from Oman

    PubMed Central

    Khan, Akhtar J.; Akhtar, Sohail; Briddon, Rob W.; Ammara, Um; Al-Matrooshi, Abdulrahman M.; Mansoor, Shahid

    2012-01-01

    Watermelon chlorotic stunt virus (WmCSV) is a bipartite begomovirus (genus Begomovirus, family Geminiviridae) that causes economic losses to cucurbits, particularly watermelon, across the Middle East and North Africa. Recently squash (Cucurbita moschata) grown in an experimental field in Oman was found to display symptoms such as leaf curling, yellowing and stunting, typical of a begomovirus infection. Sequence analysis of the virus isolated from squash showed 97.6–99.9% nucleotide sequence identity to previously described WmCSV isolates for the DNA A component and 93–98% identity for the DNA B component. Agrobacterium-mediated inoculation to Nicotiana benthamiana resulted in the development of symptoms fifteen days post inoculation. This is the first bipartite begomovirus identified in Oman. Overall the Oman isolate showed the highest levels of sequence identity to a WmCSV isolate originating from Iran, which was confirmed by phylogenetic analysis. This suggests that WmCSV present in Oman has been introduced from Iran. The significance of this finding is discussed. PMID:22852046

  14. Genome wide characterization of simple sequence repeats in watermelon genome and their application in comparative mapping and genetic diversity analysis.

    PubMed

    Zhu, Huayu; Song, Pengyao; Koo, Dal-Hoe; Guo, Luqin; Li, Yanman; Sun, Shouru; Weng, Yiqun; Yang, Luming

    2016-08-05

    Microsatellite markers are one of the most informative and versatile DNA-based markers used in plant genetic research, but their development has traditionally been difficult and costly. The whole genome sequencing with next-generation sequencing (NGS) technologies provides large amounts of sequence data to develop numerous microsatellite markers at whole genome scale. SSR markers have great advantage in cross-species comparisons and allow investigation of karyotype and genome evolution through highly efficient computation approaches such as in silico PCR. Here we described genome wide development and characterization of SSR markers in the watermelon (Citrullus lanatus) genome, which were then use in comparative analysis with two other important crop species in the Cucurbitaceae family: cucumber (Cucumis sativus L.) and melon (Cucumis melo L.). We further applied these markers in evaluating the genetic diversity and population structure in watermelon germplasm collections. A total of 39,523 microsatellite loci were identified from the watermelon draft genome with an overall density of 111 SSRs/Mbp, and 32,869 SSR primers were designed with suitable flanking sequences. The dinucleotide SSRs were the most common type representing 34.09 % of the total SSR loci and the AT-rich motifs were the most abundant in all nucleotide repeat types. In silico PCR analysis identified 832 and 925 SSR markers with each having a single amplicon in the cucumber and melon draft genome, respectively. Comparative analysis with these cross-species SSR markers revealed complicated mosaic patterns of syntenic blocks among the genomes of three species. In addition, genetic diversity analysis of 134 watermelon accessions with 32 highly informative SSR loci placed these lines into two groups with all accessions of C.lanatus var. citorides and three accessions of C. colocynthis clustered in one group and all accessions of C. lanatus var. lanatus and the remaining accessions of C. colocynthis

  15. Sperm competition and sperm cooperation: the potential role of diploid and haploid expression.

    PubMed

    Immler, Simone

    2008-03-01

    Sperm competition is a powerful selective force driving the evolution of sperm shape and function. Recent findings suggest that sperm cooperation is a potential evolutionary response to sperm competition. Sperm cooperation may enhance the performance of the ejaculate increasing a male's chance to outcompete rival males in competition for fertilisation. Whether and how sperm cooperation may evolve is the focal point of this review. The relative importance of haploid and diploid gene expression for the evolution of sperm cooperation and the potential conflict of interest between (i) haploid sperm and diploid male and (ii) among sibling sperm, since sibling sperm only share an average of 50% of their genes in a diploid organism, are discussed. Furthermore, sperm cooperation is defined and the literature for empirical evidence of sperm cooperation is reviewed in light of the author's definitions.

  16. Development and characterization of microsatellite loci for the haploid-diploid red seaweed Gracilaria vermiculophylla.

    PubMed

    Kollars, Nicole M; Krueger-Hadfield, Stacy A; Byers, James E; Greig, Thomas W; Strand, Allan E; Weinberger, Florian; Sotka, Erik E

    2015-01-01

    Microsatellite loci are popular molecular markers due to their resolution in distinguishing individual genotypes. However, they have rarely been used to explore the population dynamics in species with biphasic life cycles in which both haploid and diploid stages develop into independent, functional organisms. We developed microsatellite loci for the haploid-diploid red seaweed Gracilaria vermiculophylla, a widespread non-native species in coastal estuaries of the Northern hemisphere. Forty-two loci were screened for amplification and polymorphism. Nine of these loci were polymorphic across four populations of the extant range with two to eleven alleles observed. Mean observed and expected heterozygosities ranged from 0.265 to 0.527 and 0.317 to 0.387, respectively. Overall, these markers will aid in the study of the invasive history of this seaweed and further studies on the population dynamics of this important haploid-diploid primary producer.

  17. Development and characterization of microsatellite loci for the haploid–diploid red seaweed Gracilaria vermiculophylla

    PubMed Central

    Byers, James E.; Greig, Thomas W.; Strand, Allan E.; Weinberger, Florian

    2015-01-01

    Microsatellite loci are popular molecular markers due to their resolution in distinguishing individual genotypes. However, they have rarely been used to explore the population dynamics in species with biphasic life cycles in which both haploid and diploid stages develop into independent, functional organisms. We developed microsatellite loci for the haploid–diploid red seaweed Gracilaria vermiculophylla, a widespread non-native species in coastal estuaries of the Northern hemisphere. Forty-two loci were screened for amplification and polymorphism. Nine of these loci were polymorphic across four populations of the extant range with two to eleven alleles observed. Mean observed and expected heterozygosities ranged from 0.265 to 0.527 and 0.317 to 0.387, respectively. Overall, these markers will aid in the study of the invasive history of this seaweed and further studies on the population dynamics of this important haploid–diploid primary producer. PMID:26339541

  18. Genetic selection and liquid medium conditions improve the yield of androgenetic plants from diploid potatoes.

    PubMed

    Uhrig, H

    1985-12-01

    Solatium tuberosum L. diploid strains with superior androgenetic capacity have been selected for from androgenetic progenies of unselected diploid material. The paper also demonstrates that the use of a liquid medium for culturing potato anthers, instead of the conventional solid agar plates, improves the yield of androgenetic embryoids. The new method, associated with two successive cycles of selection for superior androgenetic response, allows the induction and regeneration of microspore derived plants on a large scale. The best genotype (clone 21 in this paper) regenerates androgenetic plants with a frequency around 30 per each anther plated. Over 80% of the regenerated plants are diploid. It is suggested that the androgenetic embryoids mainly originate from unreduced microspores by a mechanism which maintains a heterozygous or a partly heterozygous genetic situation.

  19. Use of diploid male frequency data as an indicator of pollinator decline.

    PubMed Central

    Zayed, Amro; Roubik, David W; Packer, Laurence

    2004-01-01

    Pollination deficits in agricultural and natural systems are suggestive of large reductions in pollinator populations. However, actual declines are difficult to demonstrate using census data. Here, we show census data to be misleading because many abundant pollinators exhibit high levels of production of sterile diploid males usually found only in small inbred hymenopteran populations; Euglossa imperialis exhibits high levels of diploid male production induced by low effective population sizes (Ne approximately 15), despite being the most abundant orchid bee in lowland tropical forests in Panama. We caution that although some pollinators appear abundant on the basis of census data, their long-term persistence may be highly tenuous based on genetic evidence. We propose the use of diploid male frequency data as a metric for assessing the sustainability of bee populations. PMID:15101404

  20. Production of chimeras by aggregation of embryonic stem cells with diploid or tetraploid mouse embryos.

    PubMed

    Eakin, Guy S; Hadjantonakis, Anna-Katerina

    2006-01-01

    The production of mouse chimeras is a common step in the establishment of genetically modified animal strains. Chimeras also provide a powerful experimental tool for following cell behavior during both prenatal and postnatal development. This protocol outlines a simple and economical technique for the production of large numbers of mouse chimeras using traditional diploid morula<-->diploid embryonic stem (ES) cell aggregations. Additional steps are included to describe the procedures necessary to produce specialized tetraploid chimeras using tetraploid morula<-->diploid ES cell aggregations. This increasingly popular form of chimera produces embryos of nearly complete ES cell derivation that can be used to speed transgenic production or ask developmental questions. Using this protocol, mouse chimeras can be generated and transferred to pseudopregnant surrogate mothers in a 5-d period.

  1. Molecular cytogenetic (FISH) and genome analysis of diploid wheatgrasses and their phylogenetic relationship

    PubMed Central

    Gaál, Eszter; Molnár, István; Icsó, Diana; Badaeva, Ekaterina; Molnár-Láng, Márta

    2017-01-01

    This paper reports detailed FISH-based karyotypes for three diploid wheatgrass species Agropyron cristatum (L.) Beauv., Thinopyrum bessarabicum (Savul.&Rayss) A. Löve, Pseudoroegneria spicata (Pursh) A. Löve, the supposed ancestors of hexaploid Thinopyrum intermedium (Host) Barkworth & D.R.Dewey, compiled using DNA repeats and comparative genome analysis based on COS markers. Fluorescence in situ hybridization (FISH) with repetitive DNA probes proved suitable for the identification of individual chromosomes in the diploid JJ, StSt and PP genomes. Of the seven microsatellite markers tested only the (GAA)n trinucleotide sequence was appropriate for use as a single chromosome marker for the P. spicata AS chromosome. Based on COS marker analysis, the phylogenetic relationship between diploid wheatgrasses and the hexaploid bread wheat genomes was established. These findings confirmed that the J and E genomes are in neighbouring clusters. PMID:28278169

  2. Use of diploid male frequency data as an indicator of pollinator decline.

    PubMed

    Zayed, Amro; Roubik, David W; Packer, Laurence

    2004-02-07

    Pollination deficits in agricultural and natural systems are suggestive of large reductions in pollinator populations. However, actual declines are difficult to demonstrate using census data. Here, we show census data to be misleading because many abundant pollinators exhibit high levels of production of sterile diploid males usually found only in small inbred hymenopteran populations; Euglossa imperialis exhibits high levels of diploid male production induced by low effective population sizes (Ne approximately 15), despite being the most abundant orchid bee in lowland tropical forests in Panama. We caution that although some pollinators appear abundant on the basis of census data, their long-term persistence may be highly tenuous based on genetic evidence. We propose the use of diploid male frequency data as a metric for assessing the sustainability of bee populations.

  3. Identification of Appropriate Reference Genes for Normalization of miRNA Expression in Grafted Watermelon Plants under Different Nutrient Stresses

    PubMed Central

    Wu, Weifang; Deng, Qin; Shi, Pibiao; Yang, Jinghua; Hu, Zhongyuan; Zhang, Mingfang

    2016-01-01

    Watermelon (Citrullus lanatus) is a globally important crop belonging to the family Cucurbitaceae. The grafting technique is commonly used to improve its tolerance to stress, as well as to enhance its nutrient uptake and utilization. It is believed that miRNA is most likely involved in its nutrient-starvation response as a graft-transportable signal. The quantitative real-time reverse transcriptase polymerase chain reaction is the preferred method for miRNA functional analysis, in which reliable reference genes for normalization are crucial to ensure the accuracy. The purpose of this study was to select appropriate reference genes in scion (watermelon) and rootstocks (squash and bottle gourd) of grafted watermelon plants under normal growth conditions and nutrient stresses (nitrogen and phosphorus starvation). Under nutrient starvation, geNorm identified miR167c and miR167f as two most stable genes in both watermelon leaves and squash roots. miR166b was recommended by both geNorm and NormFinder as the best reference in bottle gourd roots under nutrient limitation. Expression of a new Cucurbitaceae miRNA, miR85, was used to validate the reliability of candidate reference genes under nutrient starvation. Moreover, by comparing several target genes expression in qRT-PCR analysis with those in RNA-seq data, miR166b and miR167c were proved to be the most suitable reference genes to normalize miRNA expression under normal growth condition in scion and rootstock tissues, respectively. This study represents the first comprehensive survey of the stability of miRNA reference genes in Cucurbitaceae and provides valuable information for investigating more accurate miRNA expression involving grafted watermelon plants. PMID:27749935

  4. Evolutionary Origin and Phylogeography of the Diploid Obligate Parthenogen Artemia parthenogenetica (Branchiopoda: Anostraca)

    PubMed Central

    Green, Andy J.; Figuerola, Jordi; Amat, Francisco; Rico, Ciro

    2010-01-01

    Background Understanding the evolutionary origin and the phylogeographic patterns of asexual taxa can shed light on the origin and maintenance of sexual reproduction. We assessed the geographic origin, genetic diversity, and phylogeographic history of obligate parthenogen diploid Artemia parthenogenetica populations, a widespread halophilic crustacean. Methodology/Principal Findings We analysed a partial sequence of the Cytochrome c Oxidase Subunit I mitochondrial gene from an extensive set of localities (including Eurasia, Africa, and Australia), and examined their phylogeographic patterns and the phylogenetic relationships of diploid A. parthenogenetica and its closest sexual relatives. Populations displayed an extremely low level of mitochondrial genetic diversity, with one widespread haplotype shared by over 79% of individuals analysed. Phylogenetic and phylogeographic analyses indicated a multiple and recent evolutionary origin of diploid A. parthenogenetica, and strongly suggested that the geographic origin of parthenogenesis in Artemia was in Central Asia. Our results indicate that the maternal sexual ancestors of diploid A. parthenogenetica were an undescribed species from Kazakhstan and A. urmiana. Conclusions/Significance We found evidence for multiple origin of parthenogenesis in Central Asia. Our results indicated that, shortly after its origin, diploid A. parthenogenetica populations underwent a rapid range expansion from Central Asia towards the Mediterranean region, and probably to the rest of its current geographic distribution. This contrasts with the restricted geographic distribution, strong genetic structure, and regional endemism of sexual Artemia lineages and other passively dispersed sexual continental aquatic invertebrates. We hypothesize that diploid parthenogens might have reached their current distribution in historical times, with a range expansion possibly facilitated by an increased availability of suitable habitat provided by

  5. Spore Fitness Components Do Not Differ Between Diploid and Allotetraploid Species of Dryopteris (Dryopteridaceae)

    PubMed Central

    QUINTANILLA, LUIS G.; ESCUDERO, ADRIÁN

    2006-01-01

    • Background and Aims Although allopolyploidy is a prevalent speciation mechanism in plants, its adaptive consequences are poorly understood. In addition, the effects of allopolyploidy per se (i.e. hybridization and chromosome doubling) can be confounded with those of subsequent evolutionary divergence between allopolyploids and related diploids. This report assesses whether fern species with the same ploidy level or the same altitudinal distribution have similar germination responses to temperature. The effects of polyploidy on spore abortion and spore size are also investigated, since both traits may have adaptive consequences. • Methods Three allotetraploid (Dryopteris corleyi, D. filix-mas and D. guanchica) and three related diploid taxa (D. aemula, D. affinis ssp. affinis and D. oreades) were studied. Spores were collected from 24 populations in northern Spain. Four spore traits were determined: abortion percentage, size, germination time and germination percentage. Six incubation temperatures were tested: 8, 15, 20, 25 and 32 °C, and alternating 8/15 °C. • Key Results Allotetraploids had bigger spores than diploid progenitors, whereas spore abortion percentages were generally similar. Germination times decreased with increasing temperatures in a wide range of temperatures (8–25 °C), although final germination percentages were similar among species irrespective of their ploidy level. Only at low temperature (8 °C) did two allotetraploid species reach higher germination percentages than diploid parents. Allotetraploids showed faster germination rates, which would probably give them a competitive advantage over diploid parents. Germination behaviour was not correlated with altitudinal distribution of species. • Conclusions The results of this study suggest that (i) relative fitness of allopolyploids at sporogenesis does not differ from that of diploid parents and (ii) neither does allopolyploidization involve a change in the success of

  6. Digital gene expression analysis of gene expression differences within Brassica diploids and allopolyploids.

    PubMed

    Jiang, Jinjin; Wang, Yue; Zhu, Bao; Fang, Tingting; Fang, Yujie; Wang, Youping

    2015-01-27

    Brassica includes many successfully cultivated crop species of polyploid origin, either by ancestral genome triplication or by hybridization between two diploid progenitors, displaying complex repetitive sequences and transposons. The U's triangle, which consists of three diploids and three amphidiploids, is optimal for the analysis of complicated genomes after polyploidization. Next-generation sequencing enables the transcriptome profiling of polyploids on a global scale. We examined the gene expression patterns of three diploids (Brassica rapa, B. nigra, and B. oleracea) and three amphidiploids (B. napus, B. juncea, and B. carinata) via digital gene expression analysis. In total, the libraries generated between 5.7 and 6.1 million raw reads, and the clean tags of each library were mapped to 18547-21995 genes of B. rapa genome. The unambiguous tag-mapped genes in the libraries were compared. Moreover, the majority of differentially expressed genes (DEGs) were explored among diploids as well as between diploids and amphidiploids. Gene ontological analysis was performed to functionally categorize these DEGs into different classes. The Kyoto Encyclopedia of Genes and Genomes analysis was performed to assign these DEGs into approximately 120 pathways, among which the metabolic pathway, biosynthesis of secondary metabolites, and peroxisomal pathway were enriched. The non-additive genes in Brassica amphidiploids were analyzed, and the results indicated that orthologous genes in polyploids are frequently expressed in a non-additive pattern. Methyltransferase genes showed differential expression pattern in Brassica species. Our results provided an understanding of the transcriptome complexity of natural Brassica species. The gene expression changes in diploids and allopolyploids may help elucidate the morphological and physiological differences among Brassica species.

  7. Understanding diploid diversity: A first step in unraveling polyploid, apomictic complexity in Amelanchier.

    PubMed

    Burgess, Michael B; Cushman, Kevin R; Doucette, Eric T; Frye, Christopher T; Campbell, Christopher S

    2015-12-01

    Delimitation of Amelanchier species is difficult because of polyploidy and gametophytic apomixis. A first step in unraveling this species problem is understanding the diversity of the diploids that contributed genomes to polyploid apomicts. This research helps clarify challenging species-delimitation problems attending polyploid, apomictic complexity. We sampled 431 diploid accessions from 13 species, of which 10 are North American and three are Old World. Quantitative morphological analyses tested the null hypothesis of no discrete groups. Using three to nine diploid accessions per species, we constructed phylogenies with DNA sequences from ETS, ITS, the second intron of LEAFY, and chloroplast regions rpoB-trnC, rpl16, trnD-trnT, and ycf6-psbM. Most Amelanchier diploid taxa are morphologically and ecogeographically distinct and genetically exclusive lineages. They rarely hybridize with one another. Nuclear and chloroplast DNA sequences almost completely resolve the Amelanchier phylogeny. The backbone is the mostly western North American clade A, eastern North American clade B, and Old World clade O. DNA sequences and morphology support clades A and O as sister taxa. Despite extensive paralogy, our LEAFY data are phylogenetically informative and identify a clade (T) of three arborescent taxa within clade B. Amelanchier diploids differ strikingly from polyploid apomicts, in that hybridization among them is rare, and they form taxa that would qualify as species by most species concepts. Knowledge of diploid morphology, phylogeny, and ecogeography provides a foundation for understanding the evolutionary history of polyploid apomicts, their patterns of diversification, and their species status. © 2015 Botanical Society of America.

  8. On the use of Ethephon as abscising agent in cv. Crimson Seedless table grape production: combination of Fruit Detachment Force, Fruit Drop and metabolomics.

    PubMed

    Rizzuti, Antonino; Aguilera-Sáez, Luis Manuel; Gallo, Vito; Cafagna, Isabella; Mastrorilli, Piero; Latronico, Mario; Pacifico, Andrea; Matarrese, Angela Maria Stella; Ferrara, Giuseppe

    2015-03-15

    The effect of 2-chloroethylphosphonic acid (Ethephon, in the following ETH) as abscising agent on cv. Crimson Seedless table grape was investigated by means of Fruit Detachment Force (FDF) and Fruit Drop (FD) analyses combined with a metabolomic study carried out by High Resolution Mass Spectrometry (HRMS) and Nuclear Magnetic Resonance (NMR) spectroscopy. The effectiveness of ETH as abscising agent was ascertained with ETH concentration ranging from 1.4 to 4.0 g/L in a two-year study. The ETH treatments caused berry drops higher than 40% and induced an increase of tartaric acid, procyanidin P2, terpenoid derivatives and peonidin-3-glucoside as well as a decrease of catechin and epicatechin. HRMS-NMR covariance analysis was carried out to correlate the fluctuations of tartaric acid NMR signals to those of MS peaks of the secondary metabolites affected by ETH treatments. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Partial root-zone drying and conventional deficit irrigation applied during the whole berry growth maintain yield and berry quality in 'Crimson Seedless' table grapes

    NASA Astrophysics Data System (ADS)

    Pérez-Pastor, Alejandro; Domingo, Rafael; De la Rosa, Jose M.°; Rosario Conesa Saura, M.°

    2016-04-01

    To compare the effects of partial root-zone drying and conventional deficit irrigation applied during post-veraison and the whole berry growth on water relations, yield and berry quality, one experiment was conducted in a commercial vineyard of 'Crimson Seedless' table grapes. Five irrigation treatments were imposed: (i) Control (CTL) irrigated to 110% of crop evapotranspiration (ETc), (ii) regulated deficit irrigation (RDI) irrigated at 50% of CTL during the non- critical period of post-verasion, (iii) continuous deficit irrigation (DIc), irrigated at 50% of CTL throughout the whole berry growing season, (iv) partial root-zone drying (PRD), irrigated similar to RDI, but alternating the irrigation applied in the dry side every 10-14 days; and (v) continuous partial root-zone drying (PRDc), irrigated as DIc but alternating the irrigation in the dry side every 10-14 days. RDI and PRD received 24% and 28% less water than CTL, respectively. These reductions were higher in DIc and PRDc (65% and 53%, respectively). Total yield was not affected by any DI strategy. Only significantly lower values were observed in the weight and height's berries in respect to CTL. However, the colour parameters evaluated increased in all DI treatments, being slightly higher in DIc and PRDc compared with RDI and PRD. In addition, total soluble solids (TSS) were significantly higher in DIc, compared to other irrigated counterparts. Our findings showed that the application of water deficit during the whole berry growth through the use of DIc and PRDc, can be considered for irrigation scheduling in 'Crimson Seedless' table grapes. Acknowledgements This work has been funded by the European Union LIFE+ project IRRIMAN (LIFE13 ENV/ES/000539).

  10. Genome-Wide Identification and Comparative Analysis of Conserved and Novel MicroRNAs in Grafted Watermelon by High-Throughput Sequencing

    PubMed Central

    Liu, Na; Yang, Jinghua; Guo, Shaogui; Xu, Yong; Zhang, Mingfang

    2013-01-01

    MicroRNAs (miRNAs) are a class of endogenous small non-coding RNAs involved in the post-transcriptional gene regulation and play a critical role in plant growth, development and stresses response. However less is known about miRNAs involvement in grafting behaviors, especially with the watermelon (Citrullus lanatus L.) crop, which is one of the most important agricultural crops worldwide. Grafting method is commonly used in watermelon production in attempts to improve its adaptation to abiotic and biotic stresses, in particular to the soil-borne fusarium wilt disease. In this study, Solexa sequencing has been used to discover small RNA populations and compare miRNAs on genome-wide scale in watermelon grafting system. A total of 11,458,476, 11,614,094 and 9,339,089 raw reads representing 2,957,751, 2,880,328 and 2,964,990 unique sequences were obtained from the scions of self-grafted watermelon and watermelon grafted on-to bottle gourd and squash at two true-leaf stage, respectively. 39 known miRNAs belonging to 30 miRNA families and 80 novel miRNAs were identified in our small RNA dataset. Compared with self-grafted watermelon, 20 (5 known miRNA families and 15 novel miRNAs) and 47 (17 known miRNA families and 30 novel miRNAs) miRNAs were expressed significantly different in watermelon grafted on to bottle gourd and squash, respectively. MiRNAs expressed differentially when watermelon was grafted onto different rootstocks, suggesting that miRNAs might play an important role in diverse biological and metabolic processes in watermelon and grafting may possibly by changing miRNAs expressions to regulate plant growth and development as well as adaptation to stresses. The small RNA transcriptomes obtained in this study provided insights into molecular aspects of miRNA-mediated regulation in grafted watermelon. Obviously, this result would provide a basis for further unravelling the mechanism on how miRNAs information is exchanged between scion and rootstock in grafted

  11. Effect of postharvest pretreatments on organic Early Superior Seedless "Sugraone" table grapes assigned to long term storage

    NASA Astrophysics Data System (ADS)

    Admane, Naouel; Verrastro, Vincenzo; Di Gennaro, Domenico; Genovese, Francesco; Altieri, Giuseppe; Carlo Di Renzo, Giovanni

    2014-05-01

    Every year a significant amount of organic table grapes is lost during postharvest mainly due to the incidence of decay, stem browning and fast alteration of the taste and aroma. The demand for this fresh product with immaculate appearance and high sensory quality in terms of flavor, is a hard challenge considering the difficulties to conserve them, with alternative safe treatments to the sulphur dioxide (SO2) which is not allowed in organic product. The aim of this experiment was to maintain the quality of organic table grapes and extend their shelf-life for medium and long term, in order to reach new distant promising markets, by using safe methods. The effectiveness of the combination of pretreatment with Generally Recognized As Safe (GRAS) compounds, physical means and storage under modified atmosphere packaging (MAP) were performed by using detached organic table grape berries as alternatives to usual industrial SO2 application. The detached organic Early Superior Seedless "Sugraone" berries were pretreated by: i) dipping in ethanol and potassium bicarbonate; ii) massive CO2 concentrations; iii) ozone (O3) fumigation; whereas, untreated berries were included in the trial as control. Moreover, all the samples were packed in thermo-sealed ALPAK bags with MAP of 2% O2:5% CO2:93% N2 and stored at 0°C for 45 days. Initially and after 15, 30 and 45 days of storage, weight loss, decay incidence, berry/skin firmness, pedicel detachment force, skin color parameters, SSC, pH, titratable acidity and sensory evaluation scores, were monitored. After 45 days of storage, the weight loss was higher in the sample pretreated with massive CO2 concentration at 70 - 90 % and the control. The samples pretreated with CO2 at 70% and O3 at 20 ppm maintained the strength of the berry linked to its pedicel, also the berry and skin firmness were statistically higher in samples pretreated with CO2 at 90 - 70% and O3 at 20 ppm in comparison with the control. The skin color parameters and

  12. Morphological observation, RNA-Seq quantification, and expression profiling: novel insight into grafting-responsive carotenoid biosynthesis in watermelon grafted onto pumpkin rootstock.

    PubMed

    Liu, Guang; Yang, Xingping; Xu, Jinhua; Zhang, Man; Hou, Qian; Zhu, Lingli; Huang, Ying; Xiong, Aisheng

    2017-03-01

    Watermelon is an important and economical horticultural crop in China, where ~20% of the plants are grafted. The development of grafted watermelon fruit involves a diverse range of gene interactions that results in dynamic changes in fruit. However, the molecular mechanisms underlying grafting-induced fruit quality change are unclear. In the present study, we measured the lycopene content by high-performance liquid chromatography and used RNA-Seq (quantification) to perform a genome-wide transcript analysis of fruits from watermelon grafted onto pumpkin rootstock (pumpkin-grafted watermelon, PGW), self-grafted watermelon (SGW), and non-grafted watermelon (NGW). The results showed variation in the lycopene content in the flesh of PGW fruits, first increasing and then decreasing in the four stages, which was different from the trend in the flesh of NGW and SGW fruits. The transcriptome profiling data provided new information on the grafting-induced gene regulation of lycopene biosynthesis during fruit growth and development. The expression levels of 33 genes from 8 gene families (GGPS, PSY, PDS, ZDS, CRTISO, LCYb, LCYe, and CHY) related to lycopene biosynthesis, which play critical roles in fruit coloration and contribute significantly to fruit phytonutrient values, were monitored during the four periods of fruit development in watermelon. Compared with those of NGW and SGW, 14 genes were differentially expressed in PGW during fruit development, suggesting that these genes possibly help to mediate lycopene biosynthesis in grafted watermelon fruit. Our work provides some novel insights into grafting-responsive carotenoid metabolism and its potential roles during PGW fruit development and ripening. © The Author 2016. Published by Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Characterization, expression patterns and functional analysis of the MAPK and MAPKK genes in watermelon (Citrullus lanatus).

    PubMed

    Song, Qiuming; Li, Dayong; Dai, Yi; Liu, Shixia; Huang, Lei; Hong, Yongbo; Zhang, Huijuan; Song, Fengming

    2015-12-23

    Mitogen-activated protein kinase (MAPK) cascades, which consist of three functionally associated protein kinases, namely MEKKs, MKKs and MPKs, are universal signaling modules in all eukaryotes and have been shown to play critical roles in many physiological and biochemical processes in plants. However, little or nothing is known about the MPK and MKK families in watermelon. In the present study, we performed a systematic characterization of the ClMPK and ClMKK families including the identification and nomenclature, chromosomal localization, phylogenetic relationships, ClMPK-ClMKK interactions, expression patterns in different tissues and in response to abiotic and biotic stress and transient expression-based functional analysis for their roles in disease resistance. Genome-wide survey identified fifteen ClMPK and six ClMKK genes in watermelon genome and phylogenetic analysis revealed that both of the ClMPK and ClMKK families can be classified into four distinct groups. Yeast two-hybrid assays demonstrated significant interactions between members of the ClMPK and ClMKK families, defining putative ClMKK2-1/ClMKK6-ClMPK4-1/ClMPK4-2/ClMPK13 and ClMKK5-ClMPK6 cascades. Most of the members in the ClMPK and ClMKK families showed differential expression patterns in different tissues and in response to abiotic (e.g. drought, salt, cold and heat treatments) and biotic (e.g. infection of Fusarium oxysporum f. sp. niveum) stresses. Transient expression of ClMPK1, ClMPK4-2 and ClMPK7 in Nicotiana benthamiana resulted in enhanced resistance to Botrytis cinerea and upregulated expression of defense genes while transient expression of ClMPK6 and ClMKK2-2 led to increased susceptibility to B. cinerea. Furthermore, transient expression of ClMPK7 also led to hypersensitive response (HR)-like cell death and significant accumulation of H2O2 in N. benthamiana. We identified fifteen ClMPK and six ClMKK genes from watermelon and analyzed their phylogenetic relationships, expression

  14. Biochemical evaluation of triploid progenies of diploid × tetraploid breeding populations of Camellia for genotypes rich in catechin and caffeine.

    PubMed

    Das, Sourabh Kumar; Sabhapondit, Santanu; Ahmed, Giasuddin; Das, Sudripta

    2013-06-01

    To verify the quality of triploid varieties of Camellia tea species at the secondary metabolite level, we tested caffeine and catechin profiles of 97 F(1) segregating progenies in two breeding populations with a common tetraploid parent and diploid parents of two geographic and varietal origins. Catechin and caffeine levels of the triploid progenies were quantified and compared against their diploid parent. Some of the progenies showed better performance than their diploid parent. Most of the progenies of the diploid C. sinensis × tetraploid cross showed heterosis for caffeine and EGCG. Progenies of the C. assamica subsp. lasiocalyx × tetraploid cross showed heterosis for +C, EC, EGC, and TC. The genomic contributions of the diploid parent seem to be the main factor in the variation between the two populations. Our studies showed quantitative enhancement of some of the quality-related parameters in tea, providing a platform to refocus on this classical breeding approach for developing quality cultivars in tea.

  15. Genome-wide identification and comparative analysis of grafting-responsive mRNA in watermelon grafted onto bottle gourd and squash rootstocks by high-throughput sequencing.

    PubMed

    Liu, Na; Yang, Jinghua; Fu, Xinxing; Zhang, Li; Tang, Kai; Guy, Kateta Malangisha; Hu, Zhongyuan; Guo, Shaogui; Xu, Yong; Zhang, Mingfang

    2016-04-01

    Grafting is an important agricultural technique widely used to improve plant growth, yield, and adaptation to either biotic or abiotic stresses. However, the molecular mechanisms underlying grafting-induced physiological processes remain unclear. Watermelon (Citrullus lanatus L.) is an important horticultural crop worldwide. Grafting technique is commonly used in watermelon production for improving its tolerance to stresses, especially to the soil-borne fusarium wilt disease. In the present study, we used high-throughput sequencing to perform a genome-wide transcript analysis of scions from watermelon grafted onto bottle gourd and squash rootstocks. Our transcriptome and digital gene expression (DGE) profiling data provided insights into the molecular aspects of gene regulation in grafted watermelon. Compared with self-grafted watermelon, there were 787 and 3485 genes differentially expressed in watermelon grafted onto bottle gourd and squash rootstocks, respectively. These genes were associated with primary and secondary metabolism, hormone signaling, transcription factors, transporters, and response to stimuli. Grafting led to changes in expression of these genes, suggesting that they may play important roles in mediating the physiological processes of grafted seedlings. The potential roles of the grafting-responsive mRNAs in diverse biological and metabolic processes were discussed. Obviously, the data obtained in this study provide an excellent resource for unraveling the mechanisms of candidate genes function in diverse biological processes and in environmental adaptation in a graft system.

  16. The genome sequences of Arachis duranensis and Arachis ipaensis, the diploid ancestors of cultivated peanut

    USDA-ARS?s Scientific Manuscript database

    Cultivated peanut (Arachis hypogaea) is an allotetraploid with closely related subgenomes of total size ~2.7 Gb. This makes assembly of chromosomal pseudomolecules very challenging. Here we report genome sequences of cultivated peanut’s diploid ancestors (A. duranensis and A. ipaënsis). We show they...

  17. Aneuploid progenies of triploid hybrids between diploid and tetraploid loach Misgurnus anguillicaudatus in China.

    PubMed

    Li, Ya-Juan; Gao, Yang-Chun; Zhou, He; Ma, Hai-Yan; Lin, Zhong-Qiao; Ma, Tian-Yu; Sui, Yi; Arai, Katsutoshi

    2016-10-01

    Triploid Chinese loach, Misgurnus anguillicaudatus, hybrids between tetraploids from Hubei Province and diploids from Liaoning Province were mated with either diploid wild-type or triploid hybrids to analyze viability and ploidy of the resultant progenies. Both triploid males and females generated fertile gametes, but progenies from the crosses using gametes of triploid hybrids did not survive beyond the larval stages. In crosses between wild-type diploid females and triploid hybrid males, embryos ranging from 2.2n to 2.6n were predominant with a mode of either 2.4n (chromosome numbers 59, 60, 61) or 2.5n (chromosome numbers 62, 63). Those from the crosses between triploid hybrid females and diploid males gave a modal ploidy level at approximately 2.5n in one case, but a shift to a higher ploidy level was observed in other embryos. In the progenies between triploid hybrid females and males, the ploidy level at approximately 3.0n (chromosome numbers 74, 75, 76) was most frequent. The cytogenetic results of the progenies suggest the production of aneuploid gametes with a modal ploidy level at approximately 1.5n in triploid hybrids. However, a shift to higher chromosome numbers in gametes was observed in certain cases, suggesting the involvement of mortality selection of gametes and/or zygotes with lower chromosome numbers.

  18. Phenotypic and Transcriptomic Analyses of Autotetraploid and Diploid Mulberry (Morus alba L.)

    PubMed Central

    Dai, Fanwei; Wang, Zhenjiang; Luo, Guoqing; Tang, Cuiming

    2015-01-01

    Autopolyploid plants and their organs are often larger than their diploid counterparts, which makes them attractive to plant breeders. Mulberry (Morus alba L.) is an important commercial woody plant in many tropical and subtropical areas. In this study, we obtained a series of autotetraploid mulberry plants resulting from a colchicine treatment. To evaluate the effects of genome duplications in mulberry, we compared the phenotypes and transcriptomes of autotetraploid and diploid mulberry trees. In the autotetraploids, the height, breast-height diameter, leaf size, and fruit size were larger than those of diploids. Transcriptome data revealed that of 21,229 expressed genes only 609 (2.87%) were differentially expressed between diploids and autotetraploids. Among them, 30 genes were associated with the biosynthesis and signal transduction of plant hormones, including cytokinin, gibberellins, ethylene, and auxin. In addition, 41 differentially expressed genes were involved in photosynthesis. These results enhance our understanding of the variations that occur in mulberry autotetraploids and will benefit future breeding work. PMID:26402678

  19. Phenotypic and Transcriptomic Analyses of Autotetraploid and Diploid Mulberry (Morus alba L.).

    PubMed

    Dai, Fanwei; Wang, Zhenjiang; Luo, Guoqing; Tang, Cuiming

    2015-09-22

    Autopolyploid plants and their organs are often larger than their diploid counterparts, which makes them attractive to plant breeders. Mulberry (Morus alba L.) is an important commercial woody plant in many tropical and subtropical areas. In this study, we obtained a series of autotetraploid mulberry plants resulting from a colchicine treatment. To evaluate the effects of genome duplications in mulberry, we compared the phenotypes and transcriptomes of autotetraploid and diploid mulberry trees. In the autotetraploids, the height, breast-height diameter, leaf size, and fruit size were larger than those of diploids. Transcriptome data revealed that of 21,229 expressed genes only 609 (2.87%) were differentially expressed between diploids and autotetraploids. Among them, 30 genes were associated with the biosynthesis and signal transduction of plant hormones, including cytokinin, gibberellins, ethylene, and auxin. In addition, 41 differentially expressed genes were involved in photosynthesis. These results enhance our understanding of the variations that occur in mulberry autotetraploids and will benefit future breeding work.

  20. Synthesis of trigeneric hybrids of hexaploid wheat with diploid wheatgrasses: Specificity of chromosome pairing

    USDA-ARS?s Scientific Manuscript database

    Wild grasses in the tribe Triticeae are excellent sources of genes for superior traits, including resistance to various diseases. Diploid wheatgrasses – Lophopyrum elongatum (Host) Á. Löve (2n = 2x = 14; EE genome) and Thinopyrum bessarabicum (Savul. & Rayss) Á. Löve (2n = 2x = 14; JJ genome) – are...