Submitted to: Journal of Theoretical and Applied Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/24/2003
Publication Date: 5/1/2004
Citation: Sharma, K.D., Winter, P., Muehlbauer, F.J. 2004. Molecular mapping of fusarium oxysporum f. sp. ciceris race 3 resistance gene in chickpea.. Journal of Theoretical and Applied Genetics. 108: 1243-1248. Interpretive Summary: Fusarium wilt of chickpea is a devastating soil borne disease throughout the world and also in the U.S. Eight races of the disease causing pathogen have been reported and several of those races can be found in U.S. production regions. In this research we determined the genetics of resistance to race 3 and determined the location of the gene for resistance to the race in the chickpea genome. Our findings indicate that the resistance gene is located close to genes for resistance to other races of the pathogen a fact that provides interesting insights into the evolution of resistance to the different races of the pathogen. The results indicate a clustering of fusarium wilt resistance genes and that transfer of those genes to improved germplasm can be accomplished relatively easily. In addition, DNA markers for the resistance genes were identified and can be used in a marker assisted selection program. Marker assisted selection enables a plant breeder to use a closely linked marker in the breeding process rather than costly and time consuming direct selection for resistance. These findings can accelerate breeding programs and lead to more rapid development of chickpea germplasm with improved disease resistance.
Technical Abstract: Sequence tagged microsatellite site (STMS) and sequence-tagged-site (STS) markers linked closely to Fusarium oxysporum f. sp. ciceris race 3 resistance gene in chickpea were identified and linkage between three wilt resistance genes was elucidated. The resistance to race 3 in chickpea germplasm accession WR-315 was inherited as a single gene, designated foc-3, in 100 F7 recombinant inbred lines (RILs) derived from the cross of WR-315 (resistant) x C-104 (susceptible). The foc-3 gene was mapped 1.1 cM from STMS markers TA96 and TA27 and STS marker CS27A. Another STMS marker, TA194, at 13.2 cM flanked the gene on the other side. Linkage between foc-3 and two other chickpea wilt resistance genes, foc-1 (syn. h1) and foc-4, was established. foc-3 was mapped 10.5 cM from foc-1 and 9.4 cM from foc-4 whereas foc-1 and foc-4 are closely linked at 1.1 cM. The identification of closely linked markers to resistance genes will facilitate marker-assisted selection for introgression of the race 3 resistance gene to susceptible chickpea lines. STMS markers TA96 and TA27, being co-dominant in nature, may be used to elucidate the allelic status of F1, F2 and F3 progenies.