|Tullu, A. - WA. STATE UNIVERSITY|
|Kaiser, W. - USDA-ARS (RETIRED)|
Submitted to: Euphytica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 12, 1999
Publication Date: N/A
Interpretive Summary: Fusarium wilt caused by Fusarium oxysporum f. Sp. ciceris is a major disease of chickpea. Development of disease resistant varieties is the most economical means of control. Alternative forms of the pathogen (races) have been identified which are capable of overcoming resistance. This study was undertaken to determine the inheritance of genes conferring resistance to race 4 of Fusarium wilt and identify closely linked molecula markers. The results show that two genes were responsible for resistance to race 4 of Fusarium wilt and a single marker, CS-27 (700), closely linked to one of the genes for resistance was identified. The marker was previously reported to be linked to the gene for resistance to race 1 in a different genetic population suggesting that the genes for resistance to race 1 and race 4 are located in close proximity in the Cicer genome. This information will facilitate the transfer of a block of resistance genes to adapted varieties.
Technical Abstract: Fusarium wilt caused by Fusarium oxysporum Schelechtend.:Fr f.sp. ciceris (Padwick) Matuo & Sato is a devastating chickpea disease. The current study was conducted to determine the inheritance of the gene(s) for resistance to race 4 of fusarium wilt and to identify linked RAPD markers using an early wilting line, JG-62, as a susceptible parent. Genetic analysis was performed on the F1s, F2s and F3 families from the cross of Surutato-77xJG-62. The F3 families were inoculated with a spore suspension of the race 4 wilt pathogen and the results were used to infer the genotypes of the parent F2 plants. Results indicated that two independent genes controlled resistance to race 4. Linkage analysis of a candidate RAPD marker, CS-27(700) and the inferred F2 phenotypic data showed that this marker locus is linked to one of the resistance genes. Allelism indicated that the two resistance sources, Surutato-77 and WR-315, shared common alleles for resistance and two susceptible genotypes,C-104 and JG-6 carried alleles for susceptibility. The PCR-based marker, CS-27(700) was previously reported to be linked to the gene for resistance to race 1 in a different population which suggested that the genes for resistance to races 1 and 4 are in close proximity in the Cicer genome.