Download or read book Identification of Necrosis inducing Strains of Bean Common Mosaic Virus and Breeding for Resistance written by Milton A. Morales Lopez and published by . This book was released on 1983 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bean Common Mosaic written by Francisco José Morales and published by CIAT. This book was released on 1989 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gene Ecology of the Climbing Common Bean Phaseolus Vulgaris Bean Common Mosaic Virus Bean Common Mosaic Necrosis Virus BCMV BCMVN Relationship in Rwanda written by Alice Kabeja and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Common beans (Phaseolus vulgaris) are nutritionally, culturally, and economically an important legume crop in Rwanda. Beans provide 32 and 65 percent of calories and protein intake in the Rwandan diet, whereas protein sourced from animal provides only 4 percent of the protein intake. Unfortunately, common bean production is constrained by multiple biotic and abiotic factors in this country. Among others, Bean common mosaic virus and Bean common mosaic necrosis virus (BCMV/BCMNV) are seedborne viral pathogens that are the main constraint in common bean production. The only effective control of these pathogens is through the use of genetic resistance. Currently, the status of BCMV/BCMNV in Rwanda is not known. To contribute to the research in breeding common bean against BCMV/BCMNV in Rwanda, I sought to better understand the variability and biology of the BCMV/BCMNV pathogen to assist in developing a resistance strategy in common bean that is broader and stronger. In the first chapter, I was interested in determining the types of BCMV/BCMNV strains that are present in Rwanda. I was also interested in identifying the selective pressures these viruses are subjected to and how they govern the evolution of these viruses in Rwanda. Furthermore, I wanted to find out if there are alternate hosts other than common bean for BCMV/BCMNV in Rwanda. To gain this information, I surveyed common bean fields extensively in high-altitude areas of Rwanda. The biological and molecular pathogenic characterization studies of isolates of BCMV and BCMNV resulting from these surveys revealed the exclusive presence of BCMNV in Rwanda. No BCMV strain were found. We observed the predominance of the NL-3 strain of BCMNV. The study of genetic diversity for coat protein (CP) fragment of the BCMNV isolates showed a low genetic diversity ([pi] = 0.015623). The mean [omega] (dN/dS) value for CP of 27 isolates analyzed here was less than 1.0, indicating that the CP segment of BCMNV in Rwanda is subject to negative or purifying selection. No alternative hosts to Phaseolus vulgaris for either BCMV or BCMNV were identified in this study. For now, the resistance of BCMV/BCMNV in host plant is controlled by seven resistance genes: one dominant gene (I gene), five recessive strain-specific genes (bc-1, bc-12, bc-2, bc-22, and bc-3), and one strain-nonspecific epistatic gene (bc-u). However, few studies have been carried out on bc-12 (Miklas et al.; 2000). In the second chapter, through the development and evaluation of Recombinant Inbreed Lines (RIL) under greenhouse conditions, we investigated if any minor, quantitative loci could be identified for resistance to BCMNV, which would have originated in either of the parents, RWV3006 (bc-12) or Mshindi (bc-12), and would complement the major resistance gene bc-12. A quantitative trait loci (QTL) study done on these RILs confirmed the presence of bc-12 gene (SS715647636 QTL) on chromosome PV03 as expected. However, another QTL (SS715645701) with a smaller effect was found on Pv09. Interestingly, the positive (resistant) allele at this QTL came from RWV 3006, the susceptible parent. Results from this study showed that the combination of both QTLs increases resistance, either at the heterozygous or homozygous state. It sets the stage for further surveys of minor viral resistance genes in common-bean germplasm. To facilitate future breeding efforts, in the third chapter I attempted to obtain tightly-linked markers useful for marker-assisted selection (MAS) of the bc-12 gene in the presence of other epistatic virus resistance genes. These markers should be more broadly applicable to different genetic backgrounds, reproducible across laboratories, and able to distinguish homozygotes from heterozygotes (co-dominant). Based on a known SNP marker linked to bc-12 resistance gene, we developed a dCAPS (derived Cleaved Amplified Polymorphic Sequence) marker. However, it was not possible to clearly visualize the polymorphism generated by the designed dCAPSHindIII marker on agarose gels in all tested genotypes. This may be explained by the small size of the marker. The low resolution of the agarose gel could not detect small size differences as effectively as polyacrylamide gel electrophoresis, which can distinguish fragments with few (one to five) base pairs difference. We suggest that the marker should be tested in a larger number of different bean seed types to ascertain its usefulness in different bean classes. Furthermore, in future work with this dCAPSHindIII marker, the use of polyacrylamide gel could facilitate effective discrimination between DNA fragments from the resistant and susceptible parents.
Download or read book Breeding for Resistance to Bean Common Mosaic Necrosis Virus and Molecular Tagging of Bc 3 Gene in Common Bean written by Mukeshimana. Gérardine and published by . This book was released on 2003 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Determining the Mechanism of the Recessive Resistance to Bean Common Mosaic Virus BCMV Conferred by the Bc 1 and Bc 2 Recessive Genes in Common Bean and Biological and Molecular Characterization of a New Strain of BCMV written by Gardenia Edith Orellana Arreaga and published by . This book was released on 2019 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bean common mosaic virus (BCMV) is an important pathogen affecting common bean and other legumes. BCMV is an aphid-transmitted virus, which can also be seed-transmissible in common bean with efficiencies of up to 80%, depending on virus strain and bean cultivar. The virus belongs to the genus Potyvirus (family Potyviridae), having an approximately 10-kb single-stranded, positive-sense RNA genome. BCMV resistance in common bean is governed by one dominant (I) gene and four recessive (bc-u, bc-1, bc-2, and bc-3) genes which are deployed by breeders in different combinations to protect commercial bean cultivars against the virus. The dominant I gene confers extreme resistance or immunity against all strains of BCMV when the temperature stays below 30°C, and variable types of local and systemic necrosis when temperature exceeds 30°C. The bc-3 gene was identified as an eIF4E translation initiation factor gene mediating resistance through disruption of the interaction between this protein and the VPg protein of the virus. The mode of action of bc-1 and bc-2 in expression of BCMV resistance was unknown until this work. To investigate the possible role of both bc-1 and bc-2 genes in replication, cell-to-cell, and long distance movement of BCMV in P. vulgaris, we tested virus spread of eight BCMV isolates representing pathogroups I, IV, VI, VII, and VIII, in a set of bean differentials expressing different combinations of six resistance alleles including bc-u, bc-1, bc-12, bc-2, bc-22, and bc-3. The data suggest that bc-1 and bc-2 recessive resistance genes have no effect on the replication and cell-to-cell movement of BCMV, but affect systemic spread of BCMV in common bean. The BCMV resistance conferred by bc-1 and bc-2 and affecting systemic spread was found only partially effective when these two genes were expressed singly. The efficiency of the restriction of the systemic spread of the virus was greatly enhanced when the alleles of bc-1 and bc-2 genes were combined together.Beside common bean, there are other crop legumes that are susceptible to BCMV, such as peanut, soybean, and azuki bean. In this thesis, I described a new strain of BCMV from lima bean with distinct biological and molecular characteristics found in Honolulu, HI. This new BCMV strain, BCMV-A1, was able to partially overcome resistance to the virus conferred by bc-1 and bc-2 alleles in common bean, establishing an asymptomatic systemic infection in some common bean cultivars. Later, two BCMV isolates were found in commercial common bean samples in Idaho exhibiting 99% identity to BCMV-A1 in partial genome sequence. This new BCMV strain from lima bean, BCMV-A1, may present a threat for the common bean production.
Download or read book Genetic Interaction Between Phaseolus Vulgaris and Bean Common Mosaic Virus with Implications for Strain Identification and Breeding for Resistance written by and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Genetic Interaction Between Phaseolus Vulgaris and Bean Common Mosaic Virus with Implications for Strain Identification and Breeding for Resistance written by E. Drijfhout and published by Bernan Press(PA). This book was released on 1978 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: General introduction; Review of the literature and aims of this study; Materials and methods; Analysis of host reaction and identification of strains; Inheritance of resistance of plants with recessive alleles of the necrosis gene; Genotypes for resistance and pathogenicity; Inheritance of resistance of plants with dominant necrosis gene; Some implications for breeding.
Download or read book Recombinants of Bean Common Mosaic Virus BCMV and Genetic Determinants of BCMV Involved in Overcoming Resistance in Common Beans written by Xue Feng and published by . This book was released on 2014 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bean common mosaic virus (BCMV) exists as a complex of strains, which have been classified into seven pathogroups. These BCMV strains and strains of the closely related Bean common mosaic necrosis virus (BCMNV) can be distinguished based on their biological, molecular and serological properties. Seven resistance genes govern interactions of common beans (Phaseolus vulgaris ) and BCMV/BCMNV strains: one dominant I gene, and six recessive genes, bc-u, bc-1 and an allelic bc-12, bc-2 and an allelic bc-22, and bc-3. Prior to this work, virus genetic determinants involved in pathogenicity interactions of BCMV with resistance genes were not identified or mapped. Here, we conducted a systematic study of biological and molecular properties of a group of field-collected and reference BCMV isolates in order to identify genetic determinants involved in interactions with three recessive genes, bc-1, bc-2, and bc-22, and the dominant I gene. Through comparative genomics of four closely related BCMV isolates from the RU1 strain group, and three other BCMV strains, US1, US10, and NY15P, putative genetic determinants interacting with recessive genes, bc-1, bc-2, and bc-22, as well as the dominant I gene in P. vulgaris were identified and mapped to the P1 and HC-Pro regions. Genome diversity we found in this study suggested BCMV strains represented multiple recombinants, and the occurrence of recombination in BCMV genome may or may not lead to pathogenicity changes. Due to the wide spread of recombination in BCMV strains, partial sequencing cannot be a reliable means of BCMV strain classification..
Download or read book Viruses and Virus Diseases of Vegetables in the Mediterranean Basin written by Gad Loebenstein and published by Academic Press. This book was released on 2012-06-25 with total page 596 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume of Advances in Virus Research focuses on mycoviruses. The authors and reviews represent the most current and cutting-edge research in the field. A broad range of research is presented from research experts. Contributions from leading authorities Informs and updates on all the latest developments in the field
Download or read book Proccedings of the Second International Scientific Meeting Phaseolus Beans Advanced Biotechnology Research Network BARN written by and published by CIAT. This book was released on with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bean Production Problems in the Tropics written by Howard F. Schwartz and published by CIAT. This book was released on 1989 with total page 750 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first section reviews trends of bean production and constraints in Latin America and Africa. The second section covers fungal diseases. The third section, bacterial diseases. The fourth section, viral and mycoplasma diseases. The fifth section, insect pests. The last section, other bean production constraints, that is, nutritional disorders, nematodes, seed pathology, and additional problems.
Download or read book Natural Resistance Mechanisms of Plants to Viruses written by Gad Loebenstein and published by Springer Science & Business Media. This book was released on 2007-05-26 with total page 547 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a first attempt to link well-known plant resistance phenomena with emerging concepts in molecular biology. Resistance phenomena such as the local lesion response, induced resistance, "green islands" and resistance in various crop plants are linked with new information on gene-silencing mechanisms, gene silencing suppressors, movement proteins and plasmodesmatal gating, downstream signalling components, and more.
Download or read book Plant Breeding Reviews Volume 10 written by Jules Janick and published by John Wiley & Sons. This book was released on 2010-04-22 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: Part of a series which presents papers of topical interest relating to the breeding of plants important to agriculture and horticulture.
Download or read book Cucumber Mosaic Virus written by Peter Palukaitis and published by . This book was released on 2019 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plant Resistance to Viruses written by David Evered and published by John Wiley & Sons. This book was released on 2008-04-30 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concern about the environmental consequences of the widespread use of pesticides has increased, and evidence of pesticide-resistant virus vectors have continued to emerge. This volume presents a timely survey of the mechanisms of plant resistance and examines current developments in breeding for resistance, with particular emphasis on advances in genetic engineering which allow for the incorporation of viral genetic material into plants. Discusses the mechanisms of innate resistance in strains of tobacco, tomato, and cowpea; various aspects of induced resistance, including the characterization and roles of the pathogenesis-related proteins; antiviral substances and their comparison with interferon; and cross-protection between plant virus strains. Also presents several papers which evaluate the status of genetic engineering as it relates to breeding resistant plants. Among these are discussions of the potential use of plant viruses as gene vectors, gene coding for viral coat protein, satellite RNA, and antisense RNA, and practical issues such as the durability of resistant crop plants in the field.
Download or read book Seed borne plant virus diseases written by K. Subramanya Sastry and published by Springer Science & Business Media. This book was released on 2013-01-05 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seeds provide an efficient means in disseminating plant virus and viroid diseases. The success of modern agriculture depends on pathogen free seed with high yielding character and in turn disease management. There is a serious scientific concern about the transmission of plant viruses sexually through seed and asexually through plant propagules. The present book provides the latest information along with the total list of seed transmitted virus and viroid diseases at global level including, the yield losses, diagnostic techniques, mechanism of seed transmission, epidemiology and virus disease management aspects. Additional information is also provided on the transmission of plant virus and virus-like diseases through vegetative propagules. It is also well known that seed transmitted viruses are introduced into new countries and continents during large-scale traffic movements through infected germplasm and plant propogules. The latest diagnostic molecular techniques in different virus-host combinations along with disease management measures have been included. The book shall be a good reference source and also a text book to the research scientists, teachers, students of plant pathology, agriculture, horticulture, life sciences, green house managers, professional entrepreneurs, persons involved in quarantines and seed companies. This book has several important features of seed transmitted virus diseases and is a good informative source and thus deserves a place in almost all university libraries, seed companies and research organizations.
Download or read book Masters Abstracts written by and published by . This book was released on 1984 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt:
