Download or read book Molecular Markers for Resistance to Soybean Cyst Nematode Heterodera Glycines I in Soybean Glycine Max L Merr written by Ramamurthy Mahalingam and published by . This book was released on 1994 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book DNA Markers and Genetics of Resistance to Cyst Nematode and Seed Composition in Soybean Peking X Essex written by Boxing Qiu and published by . This book was released on 1998 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soybean [Glycine max (L.) Merr.] is one of the major crops in the USA and worldwide. Soybean cyst nematode (SCN), Heterodera glycines Ichinohe, causes severe damage to soybean production. In 1988, the SCN was ranked as the number one crop disease in the southern USA. To combat this pest, genetic characterization of the resistance genes to SCN and molecular approaches for tagging the resistance genes have recently been conducted. The cultivar 'Peking' is one of the most important resistance sources to SCN. It gives resistance to SCN Race Isolates 1, 3, and 5. The genetic inheritance for resistance to SCN Race 3 in Peking was studied in the past decades, but the resistance nature is complicated and the inheritance patterns for resistance to SCN Races 1 and 5 were not well documented. In this study, F 1, F 2, and F 2:3 subfamilies were used for studying the genetic background of the SCN resistance in Peking. It was discussed that resistance to SCN Races 1, 3, and 5 each were conditioned by a three-gene model, one dominant and two recessives (Rhg, rhg, rhg). The complexity of SCN multiple resistance genes in soybean and the heterogeneity of indigenous field SCN Race populations make it difficult to breed resistant soybean cultivars. Both morphological and molecular markers that are associated with the resistance to SCN are known to play an important role in tagging and transferring resistance genes from wild types into soybean cultivars. Black seed-coat color was previously reported as a morphological marker linked to SCN resistance. Our data indicated that the reddish brown seed-coat color was linked to the loci controlling resistance to SCN Race 3. The mean of the Index of Parasitism (IP) in reddish-brown seed-coat color plants was significantly less than one in the plants with black seed coat color. DNA markers associated with resistance to SCN Race 3 have been documented by a number of scientists. Restriction fragment length polymorphism (RFLP) analysis was used as a molecular marker-mediated approach to identify the markers for SCN resistance in this study. Based on the co-segregation between phenotypic SCN reactions in 200 F 2:3 families and RFLP scoring data from 200 F 2 plants, five DNA markers, A593 and T005 on linkage group (LG) B, A018 in LG E, and K014 and B072 on LG H, were associated with resistance loci for SCN Race 1, which jointly explained 57.7% of the phenotypic variation. Three markers (B072 and K014 on LG H, T005 on LG B) were linked to resistance loci for Race 3, and together explained 21.4% of the total phenotypic variation. Two markers (K011 on LG I, A963 on LG E) associated with resistance to Race 5 jointly explained 14.0% of the total phenotypic variation.

Download or read book Soybean Cyst Nematode Heterodera Glycines Resistance Genes in PI 8972 and PI 209332 Soybean written by M. da S. ASSUNCAO and published by . This book was released on 2000 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soybean cyst nematode(SCN), Heterodera glycines Ichinohe, is the most serious disease of soybean glycine max(L.) Merr., in the United States and also is a serious pest of soybean on a world-wide basis. The nematode was first found in the United States in North Carolina in 1954 and now occurs in 30 states. Crop rotation plays an important role in controlling the nematode. Control also utilizes different cropping systems and resistant soybean cultivars to supress yield loss caused by H. glycines. A racetest was developed in early 1970's to classify variability in the nematode and was expanded in late 1980's to include 16 races. Eight races have been identified in the United States and in the North Central United States race 3 is the prevalent. Several plants introductions have been found with resistance to the most important races that occur in the soybean production areas in Asia, North America, and South America. The number of resistance genes in PI 89772 and PI 209332 conferring resistance to H.glycines race 3 is not well defined. Crosses of PI 89772 x 'Lee 68', PI 88788 x PI 89772, and Lee 68 x PI 209332 were made in the field and greenhouse. To verify that F1 plants resulted from the cross rather than selfing, simple sequence repeat molecular marker analysis was used to characterize F1 plants and their parents. Several F1 and F2 families from each cross, 98 F3 families from cross PI 89772 x Lee 68, 74 F3 families from cross PI 88788 x PI 89772, and 80 F3 families from cross Lee 68 x PI 209332 were tested with an inbred line of H.glycines developedon 88788. Approximately 8,000 individual plants growing in pots containing 200 cm3 of sterilized soil were inoculated with 4,010 eggs and J2/pot. Thity days after inoculation the number of females that developed on each plant was determined. Cluster analysis revealed sets of families with a low mean number of femalesand low variance, intermediate means and high variance, and high means witha low variance, indicating F3 plants came from, respectively, homozygous resistant, heterozygous or segreganting, and homozygous susceptible F2 plants. Thus, resistance classes were considered as quantitative parameters having different levels of resistance as opposed to only two classes, either or susceptible. Chi-square analysis of segregation of phenotypic data indicated two genes confer resistance torace of H.glycines. One gene acts as a major gene (Rhgx) and the other a minor gene (Rhgy) in conferring resistance of the parents PI 89772 (Rhgx1?Rhgx1?Rhgy1?Rhgy1?) PI 88788 (Rhgx2?Rhgx2?Rhgy2?Rhgy2/), and PI 209332 (Rhgx3?Rhgx3?Rhgy3?Rhgy3) to H.glycine race 3. The same genes may occur in PI 209332 as in PI 89772, but support for this hypothesis must be obtained by studying the cross PI 209332 x PI 89772. The same major (Rhgx) and minor (Rhgy) genes occur in PI 89772 (Rhgx1?Rhgx1?Rhgy1?Rhgy1?) and PI 88788 (Rhgx2?Rhgx2?Rhgy2?Rhgy2?). The phenotypic ratios obtained in this research indicate that epsitasis occurs between loci Rhgyx and geney.

Download or read book Evaluation of Soybean Glycine Max L Merr Source of Resistance to Soybean Cyst Nematode Heterodera Glycines Ichinohe written by Beth Holmes and published by . This book was released on 1996 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Soybean Cyst Nematode written by United States. Agricultural Research Service. Crops Research Division and published by . This book was released on 1968 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Biology and Management of the Soybean Cyst Nematode written by Robert D. Riggs and published by American Phytopathological Society. This book was released on 1992 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: 1 History, distribution, and economics. 2 Systematics and morphology. 3 Epiphytology and life cycle. 4 Cellular responses to infection. 5 Population dynamics. 6 Genetics. 7 The race concept. 8 Nematode race identification, A look to the future. 9 Interactions with other organisms. 10 Host range. 11 Chemical control. 12 Management by cultural practices. 13 Biological control. 14 Breeding for resistance to soybean cyst nematode. 15 Cytopathological reactions of resistant soybean plants to nematode invasion. 16 Tolerance in soybean.

Download or read book The Soybean Cyst Nematode written by United States. Plant Pest Control Branch and published by . This book was released on 1957 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Identification and Characterization of Soybean Cyst Nematode Resistance Genes Using DNA Markers written by Vergel Cierte Concibido and published by . This book was released on 1995 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigation of Resistance to Heterodea Glycines scn in Soybean Plant Introductions pi 467312 and 507354 written by Peiqin Lu and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Soybean cyst nematode (SCN) Heterodera glycines Ichinohe is the most serious pest of soybean [Glycine max (L.) Merr.] in the world. The effectiveness of breeding soybean SCN resistant cultivars is reduced by the variation of SCN population and narrow genetic basis of resistant soybean cultivars. Hence, it is important to investigate new soybean SCN resistant sources for new genes that confer resistance to SCN field populations such as HG type 1.2.7 to provide durable resistance. Soybean plant introductions PI 467312 and PI 507354, are unique, with resistance to SCN multiple HG types respectively. However, the genetic basis of SCN resistance in these PIs is not known. The objectives of this study are to investigate the inheritance of resistance to SCN HG types 0, 1.2.7, and 1.3.6.7 in PI 467312 and the SCN resistance to SCN HG types 2.5.7 and 1.2.7 in PI 507354, to identify and map quantitative trait loci (QTL) associated with resistance to SCN HG types 0, 1.2.7, 1.3.6.7 in PI 467312 and resistance to SCN HG types 2.5.7, and 1.2.7 in PI 507354. The study showed that resistance to HG types 1.2.7, and 1.3.6.7 in Pop 467 were conditioned by one dominant and two recessive genes (Rhg rhg rhg) and resistance to HG type 0 was controlled by three recessive genes (rhg rhg rhg). Resistance to both HG types 2.5.7 and 1.2.7 in Pop 507 fit a one dominant and 3 recessive gene model (Rhg rhg rhg rhg). Two to three QTLs were associated with resistance to each HG type (race) in both populaitons.

Download or read book Characterizing Rhg1 Mediated Soybean Resistance to Soybean Cyst Nematode Using Functional and Computational Approaches written by and published by . This book was released on 2013 with total page 183 pages. Available in PDF, EPUB and Kindle. Book excerpt: Domesticated soybean, Glycine max, is an important world commodity accounting for 68% of world protein meal and 56% of world oilseed production. Soybean cyst nematode (SCN, Heterodera glycines) causes billions of dollars of economic losses annually and is considered the most economically damaging soybean disease. A previously identified locus, termed Rhg1, has a significant impact on SCN resistance, and is currently deployed in most commercially utilized SCN resistant soybean cultivars. The mechanism underlying Rhg1-mediated SCN resistance has remained elusive. This dissertation focuses on functional and computational approaches to define and characterize the genes underlying Rhg1-mediated SCN resistance. We identified three tightly clustered genes at the Rhg1 locus that each contributes to SCN resistance. We further discovered that the DNA encoding these genes is present in multiple copies in SCN-resistant parents, and this causes elevated expression of the genes. Two of the identified genes, Glyma18g02580 and Glyma18g02610, did not carry amino acid polymorphisms between resistant and susceptible Rhg1 haplotypes. The third gene, Glyma18g02590, encoding a predicted &alpha-SNAP protein did contain amino acid polymorphisms relative to the reference soybean genome Williams 82, which is SCN-susceptible. Transgenic expression of any one of these three genes in soybean roots did not discernibly improve resistance, but simultaneous expression of all three genes did enhance SCN resistance. To further explore the evolution and diversity of Rhg1, we used whole genome sequencing, fiber-FISH and related techniques to examine the structural and nucleic acid variation in the genomes of four-dozen soybean accessions. We discovered that the Rhg1 locus is commonly arranged in a single copy in all tested SCN susceptible germplasm, but is present as either a low-copy or high-copy type in SCN-resistant germplasm. These repeat copy classes are also distinguishable by expression level differences, and the presence of related but distinct alleles of the previously identified &alpha-SNAP protein. We also identified differential DNA-methylation at the locus between SCN-resistance and susceptible lines. The identification of the genes that control Rhg1-mediated resistance, and an understanding of their evolution and diversity, should foster efforts to improve the disease resistance that is available to reduce the deleterious impacts of SCN.

Download or read book Marker assisted Selection for Soybean Cyst Nematode Resistance and Accompanying Agronomic Traits written by Joann Mudge and published by . This book was released on 1999 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of the Rhg1 Gene on Resistance to Heterodera Glycines in Soybean Glycine Max written by Yuhong Li and published by . This book was released on 2003 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Monitoring Multiple Resistance to Soybean Cyst Nematode SCN Using Molecular Markers in a Breeding Population written by Jennifer Heer and published by . This book was released on 1996 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Soybean molecular breeding and genetics written by Guo-Liang Jiang and published by Frontiers Media SA. This book was released on 2023-03-29 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Molecular Characterization of Genetic Resistance to Soybean Cyst Nematode in Soybean Line SS97 6946 written by Md Sariful Islam and published by . This book was released on 2008 with total page 45 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soybean Cyst Nematode (SCN) (Heterodera glycine) is the most damaging pest of soybean and estimated annual yield losses are 1.5 billion dollars in USA. Breeding resistant cultivars is the most efficient means to control SCN but the nematode has adapted and overcomes resistance of developed soybean cultivars due to a narrow genetic base. A study was initiated in summer 2007 to investigate the genetics of resistance to SCN and identify Quantitative Trait Loci (QTL) conferring broad-spectrum SCN resistance in SS97-6946. Leaves of 160 F2 individuals from the cross PI 567476 X SS97-6946 were collected to isolate DNA in summer 2007. Three hundred forty seven polymorphic Single Sequence Repeat primer pairs out of 547 were used to genotype the F2 plants. Seeds from 160 F2:3 families were evaluated against races 1, 2, 3 and 5 for SCN bioassay following standard protocol. The ratio observed between resistant to susceptible F2:3 families revealed that SCN resistance involved three recessive genes for both race 1 and 2; two dominant and one recessive for race 3; one dominant and two recessive for race 5. Three markers mapped on linkage groups (LG) A2, E, and G and accounted for 33.8% of the total phenotypic variance for resistance to SCN race 1. One resistant QTL was detected on LG A1 accounted for 18.8% of the total phenotypic variance of race 2. Three markers mapped on LGs A2, G, and M to be associated with resistance to SCN race 3 and shared 24.9% of total phenotypic variance. Three markers on LG G alone and four markers on LGs A1, B2, M, and O were mapped and shown to be linked with SCN resistance to race 5 and accounted for 70.8% of the total phenotypic variance.

Download or read book Identification and Evaluation of Quantitative Trait Loci Associated with Resistance to HG Type 2 and Seed Quality Traits from Two Bi Parental Mapping Populations Segregating for Soybean Cyst Nematode Resistance written by Adam Brown and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Soybean cyst nematode (SCN), Heterodera glycines Ichinohe, is the most economically devastating pathogen of soybean (Glycine max [L.] Merr.) Overuse of the resistance source PI88788 has led to development of new HG types of SCN in the fields. Major genes, Rhg1 and Rhg4, provide resistance to most HG types. The objectives of this thesis were: 1) identify minor QTL contributing to SCN resistance in two recombinant inbred line populations derived from a cross between the susceptible cultivar, Neptune, and resistant LD07-3419 (PI43764-derived), and between resistant cultivar OAC 13-87C-SCN (PI88788-derived) and LD07-3419 (PI43764); 2) assess the relationship between SCN resistance and yield and seed quality. One of the four identified QTL, which is located on chromosome 6 is potentially novel; however, this result needs to be confirmed. SCN resistance was negatively correlated with protein but not with oil concentration or yield. These findings may facilitate breeding for SCN resistance.

Download or read book Molecular Characterization of Soybean Resistance to Soybean Cyst Nematode written by Xiaohong Liu and published by . This book was released on 2009 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: The soybean cyst nematode, Heterodera glycines, is a devastating pathogen to soybean worldwide. This obligate parasite establishes specialized feeding cells within host roots that are required for completion of the nematode life cycle. In resistant soybean plants, juveniles penetrate into roots, but subsequent degeneration of feeding cells prevents the nematode from further growth and development. The soybean resistance genes and signaling pathways controlling this process have not yet been identified. The Rhg4 locus, a major QTL controlling soybean resistance against H. glycines was previously sequenced and patented by two independent research groups and a gene encoding a leucine-rich repeat receptor-like kinase protein (LRR-RLK) was proposed as the gene for resistance. These claims, which have been generally accepted by the soybean community, were never validated by functional studies to confirm that this was the correct gene for resistance. In this study, a combination of approaches including TILLING, haplotyping, and complementation were not able to confirm a role for this gene in resistance to H. glycines. Consequently, further fine mapping and testing of additional candidate genes is underway. In addition, the role of salicylic acid (SA), a key signaling molecule in plant resistance to biotrophic pathogens was investigated for a role in Rhg4-mediated resistance to H. glycines. Studies measuring endogenous SA levels in response to nematode infection and parasitic success on transgenic plants compromised for SA production or on soybean roots following exogenous application with SA, suggest that SA plays a role in basal resistance, but may not play a major role in R gene-mediated resistance to H. glycines.