Genetics and Stability of Resistance to Watermelon Chlorotic Stunt Virus in Melon (Cucumis Melo L).

Experiments were carried out under field conditions at the University Gezira Research Farm, Sudan and the agroinoculation and green houses conditions in France (le Centre National de la Recherche Scientifique (CNRS*) and le Institut National de la Recherche Agronomique (INRA**) to study the inheritance and stability of resistance to watermelon chlorotic stunt virus (WCSV) in melon (C. melo L.).   The techniques of autoradiography, using the ratioactive WCSV P32, probe was used to detect WCSV in plant tissue and the phospho-imager machine was used to obtain quantified results of DNA particles within the examined plant tissue. The results indicated the presence of one dominant gene and another recessive independent gene controlling WCSV resistance in the resistant lines P1414723, P1124112 and HSD2445- 005. Multi-locational trials on resistant lines under natural field conditions revealed that the resistance to WCSV in melon is uniform and stable. Results of studying the movement of the virus within the plant tissues indicated that the blockage in the plant indigenous trafficking system was one of the mechanisms that are involved in plant resistance to WCSV in the lines P1414723, P1282448, P1124440, Pl 124112, 90625 and HSD 2445-005

Specificity of Resistance and Tolerance to Cucumber Vein Yellowing Virus in Melon Accessions and Resistance Breaking with a Single Mutation in VPg

Altres ajuts: CERCA Programme/Generalitat de CatalunyaCucumber vein yellowing virus (CVYV) is an emerging virus on cucurbits in the Mediterranean Basin, against which few resistance sources are available, particularly in melon. The melon accession PI 164323 displays complete resistance to isolate CVYV-Esp, and accession HSD 2458 presents a tolerance, i.e., very mild symptoms despite virus accumulation in inoculated plants. The resistance is controlled by a dominant allele Cvy-11, while the tolerance is controlled by a recessive allele cvy-2, independent from Cvy-11. Before introducing the resistance or tolerance in commercial cultivars through a long breeding process, it is important to estimate their specificity and durability. Upon inoculation with eight molecularly diverse CVYV isolates, the resistance was found to be isolate-specific because many CVYV isolates induced necrosis on PI 164323, whereas the tolerance presented a broader range. A resistance-breaking isolate inducing severe mosaic on PI 164323 was obtained. This isolate differed from the parental strain by a single amino acid change in the VPg coding region. An infectious CVYV cDNA clone was obtained, and the effect of the mutation in the VPg cistron on resistance to PI 164323 was confirmed by reverse genetics. This represents the first determinant for resistance-breaking in an ipomovirus. Our results indicate that the use of the Cvy-11 allele alone will not provide durable resistance to CVYV and that, if used in the field, it should be combined with other control methods such as cultural practices and pyramiding of resistance genes to achieve long-lasting resistance against CVYV

A consensus linkage map for molecular markers and Quantitative Trait Loci associated with economically important traits in melon (Cucumis melo L.)

Background A number of molecular marker linkage maps have been developed for melon (Cucumis melo L.) over the last two decades. However, these maps were constructed using different marker sets, thus, making comparative analysis among maps difficult. In order to solve this problem, a consensus genetic map in melon was constructed using primarily highly transferable anchor markers that have broad potential use for mapping, synteny, and comparative quantitative trait loci (QTL) analysis, increasing breeding effectiveness and efficiency via marker-assisted selection (MAS). Results Under the framework of the International Cucurbit Genomics Initiative (ICuGI, http://www.icugi.org webcite), an integrated genetic map has been constructed by merging data from eight independent mapping experiments using a genetically diverse array of parental lines. The consensus map spans 1150 cM across the 12 melon linkage groups and is composed of 1592 markers (640 SSRs, 330 SNPs, 252 AFLPs, 239 RFLPs, 89 RAPDs, 15 IMAs, 16 indels and 11 morphological traits) with a mean marker density of 0.72 cM/marker. One hundred and ninety-six of these markers (157 SSRs, 32 SNPs, 6 indels and 1 RAPD) were newly developed, mapped or provided by industry representatives as released markers, including 27 SNPs and 5 indels from genes involved in the organic acid metabolism and transport, and 58 EST-SSRs. Additionally, 85 of 822 SSR markers contributed by Syngenta Seeds were included in the integrated map. In addition, 370 QTL controlling 62 traits from 18 previously reported mapping experiments using genetically diverse parental genotypes were also integrated into the consensus map. Some QTL associated with economically important traits detected in separate studies mapped to similar genomic positions. For example, independently identified QTL controlling fruit shape were mapped on similar genomic positions, suggesting that such QTL are possibly responsible for the phenotypic variability observed for this trait in a broad array of melon germplasm. Conclusions Even though relatively unsaturated genetic maps in a diverse set of melon market types have been published, the integrated saturated map presented herein should be considered the initial reference map for melon. Most of the mapped markers contained in the reference map are polymorphic in diverse collection of germplasm, and thus are potentially transferrable to a broad array of genetic experimentation (e.g., integration of physical and genetic maps, colinearity analysis, map-based gene cloning, epistasis dissection, and marker-assisted selection).This work was supported in part by SNC Laboratoire ASL, Ruiter Seeds B.V., Enza Zaden B.V., Gautier Semences S.A., Nunhems B.V., Rijk Zwaan B.V., Sakata Seed Inc, Semillas Fito S. A., Seminis Vegetable Seeds Inc, Syngenta Seeds B. V., Takii and Company Ltd, Vilmorin & Cie S. A., and Zeraim Gedera Ltd (all of them as part of the support to the ICuGI); the grants AGL2009-12698-C02-02 from the Spanish "Ministerio de Ciencia e Innovacion" to AJM. NK lab was supported in part by Research Grant Award No. IS-4223-09C from BARD, the United States - Israel Binational Agricultural Research and Development Fund, and in part by Israel Science Foundation Grant No. 38606, De Ruiter Seeds, Enza Zaden, Keygene, Rijk Zwaan, Sakata Seed Corporation, Semillas Fito, Syngenta Seeds and Vilmorin Clause & Cie. AD was supported by a JAE-Doc contract from "Consejo Superior de Investigaciones Cientificas" (CSIC-Spain). MF was supported by a postdoctoral contract from CRAG. The research carried out at YX's laboratory was supported by Chinese funds (Grant No. 2008-Z42(3), 5100001, 2010AA101907).Díaz Bermúdez, A.; Fergany, M.; Formisano, G.; Ziarsolo, P.; Blanca Postigo, JM.; Fei, Z.; Staub, JE.... (2011). A consensus linkage map for molecular markers and Quantitative Trait Loci associated with economically important traits in melon. BMC Plant Biology. 11. https://doi.org/10.1186/1471-2229-11-111S1

A comprehensive genome variation map of melon identifies multiple domestication events and loci influencing agronomic traits

Melon is an economically important fruit crop that has been cultivated for thousands of years; however, the genetic basis and history of its domestication still remain largely unknown. Here we report a comprehensive map of the genomic variation in melon derived from the resequencing of 1,175 accessions, which represent the global diversity of the species. Our results suggest that three independent domestication events occurred in melon, two in India and one in Africa. We detected two independent sets of domestication sweeps, resulting in diverse characteristics of the two subspecies melo and agrestis during melon breeding. Genome-wide association studies for 16 agronomic traits identified 208 loci significantly associated with fruit mass, quality and morphological characters. This study sheds light on the domestication history of melon and provides a valuable resource for genomics-assisted breeding of this important crop.info:eu-repo/semantics/acceptedVersio

A comprehensive genome variation map of melon identifies multiple domestication events and loci influencing agronomic traits

Melon is an economically important fruit crop that has been cultivated for thousands of years; however, the genetic basis and history of its domestication still remain largely unknown. Here we report a comprehensive map of the genomic variation in melon derived from the resequencing of 1,175 accessions, which represent the global diversity of the species. Our results suggest that three independent domestication events occurred in melon, two in India and one in Africa. We detected two independent sets of domestication sweeps, resulting in diverse characteristics of the two subspecies melo and agrestis during melon breeding. Genome-wide association studies for 16 agronomic traits identified 208 loci significantly associated with fruit mass, quality and morphological characters. This study sheds light on the domestication history of melon and provides a valuable resource for genomics-assisted breeding of this important crop.This work was supported by funding from the Agricultural Science and Technology Innovation Program (to Yongyang Xu, S.H., Z.Z. and H.W.), the China Agriculture Research System (CARS-25 to Yongyang Xu and H.W.), the Leading Talents of Guangdong Province Program (00201515 to S.H.), the Shenzhen Municipal (The Peacock Plan KQTD2016113010482651 to S.H.), the Dapeng district government, National Natural Science Foundation of China (31772304 to Z.Z.), the Science and Technology Program of Guangdong (2018B020202007 to S.H.), the National Natural Science Foundation of China (31530066 to S.H.), the National Key R&D Program of China (2016YFD0101007 to S.H.), USDA National Institute of Food and Agriculture Specialty Crop Research Initiative (2015-51181-24285 to Z.F.), the European Research Council (ERC-SEXYPARTH to A.B.), the Spanish Ministry of Economy and Competitiveness (AGL2015–64625-C2-1-R to J.G.-M.), Severo Ochoa Programme for Centres of Excellence in R&D 2016–2010 (SEV-2015–0533 to J.G.-M.), the CERCA Programme/Generalitat de Catalunya to J.G.-M. and the German Science Foundation (SPP1991 Taxon-OMICS to H.S.)

Légumes : l’innovation pour tous

Résistance aux bio-agresseurs, diversification, qualité, rusticité, agriculture biologique sont les principales innovations marquantes de ces dernières années en matière d’espèces légumières. L’amateur, qui n’a pas les mêmes exigences que le professionnel, n’est pas oublié..

Légumes : l’innovation pour tous

Résistance aux bio-agresseurs, diversification, qualité, rusticité, agriculture biologique sont les principales innovations marquantes de ces dernières années en matière d’espèces légumières. L’amateur, qui n’a pas les mêmes exigences que le professionnel, n’est pas oublié..

Des plantes alimentaires aquatiques

L’homme ne consomme que très peu de plantes poussant en permanence dans l’eau. Celles que l’on considère comme plantes aquatiques sont la plupart du temps des végétaux poussant en milieux humides, voire très humides, comme le riz ou le cresson. Si leur multiplication est aisée, il faut veiller à leur état sanitaire face au risque de transmission de maladies à l’homme

La bactériose du melon (écologie et stratégies de lutte contre Pseudomonas syringae pv.aptata)

La bactériose du melon, causée par Pseudomonas syringae pv.aptata, est une maladie importante dans le Sud-Ouest de la France, avec des foyers éphémères dans le Sud-Est, entraînant des pertes économiques significatives lorsque les conditions sont favorables. L'optimisation de la lutte implique l'identification des réservoirs d'inoculum, une meilleure connaissance de la survie des bactéries en phase épiphyte et la recherche de sources de résistance au sein de l'espèce Cucumis melo. Cette étude a consisté à la mise au point d'une technique de détection et de son application pour détecter P. syringae pv.aptata dans des sources potentielles de contamination dans lesquelles la bactérie est capable de survivre en l'absence de culture de melon. Les résultats ont montré que P. syringae pv.aptata est présent naturellement à de faible fréquence dans les lacs collinaires servant à l'irrigation des cultures de melon pendant la période hivernale. De même, une étude en contamination artificielle a permis de montrer que P. syringae pv.aptata est capable de survivre dans le sol en association avec des déchets de culture. L'effet de la phase épiphyte sur les modifications phénotypiques des cellulus de P. syringae pv.aptata a été étudié. Les résultats montrent que P.syringae pv.aptata est capable de s'adapter lors de la colonisation épiphyte, en réduisant sa taille et en augmentant sa résistance à un oxydant, par rapport à une culture sur milieu synthétique. Nous avons également recherché les sources de résistance chez l'espèce Cucumis melo. Un génotype dont les fruits sont résistants à P. syringae pv.aptata a été trouvé parmi la collection de C.melo. En revanche, les parties végétatives de tous les 282 génotypes testés sont sensibles à cet agent pathogène. L'ensemble des résultats obtenus permettra d'orienter les recherches vers des stratégies de contrôle plus efficaces contre cette nouvelle maladie en focalisant dans un premier temps sur les facteurs conduisant à la modification du phénotype de P. syringae pv. aptata en phase épiphyte et dans un second temps sur la détermination de l'importance épidémologique des différentes sources d'inoculum.LYON1-BU.Sciences (692662101) / SudocSudocFranceF

Construction d'une carte génétique de référence du melon (Cucumis melo L.) et étude du contrôle génétique du développement et de la maturation du fruit

AIX-MARSEILLE2-BU Sci.Luminy (130552106) / SudocSudocFranceF