Genetic Analysis of Resistance to Aspergillus flavus Infection in Groundnut Arachis hypogaea L

Abstract

The present investigation was carried out in MARS, Dharwad to study the inheritance of newlineresistance to Aspergillus flavus and improve the agronomic traits with resistance in F3 generation newlineduring summer 2013-14 to 2015-16. A total number of 388 genotypes were screened by in vitro spore newlinespray and pin prick methods. Among them two lines ICGV-02266 (3.23 and#956;g/kg) and ICGV-02207 (6.25 newlineand#956;g/kg) recorded stable resistance hence these were used for hybridization with GPBD-5 (2976.15 newlineand#956;g/kg) and TGLPS-3 (3408.10 and#956;g/kg) to generate segregating population for further studies. newlineInheritance studies were conducted in F2 and confirmed in backcross and F3 generation. Character newlineassociation and variability studies of Aspergillus flavus seed colonization and infection resistance with newlineother traits was done in F3 generation. newlineIn all four crosses, segregation ratio of 3 resistant: 13 susceptible was obtained in F2 newlinepopulation for Aspergillus flavus seed colonization resistance. The segregation ratio of backcross and newlineF3 populations confirmed the role of inhibitory gene interaction. The inheritance ratio of 1 resistant: 15 newlinesusceptible was observed for Aspergillus flavus seed infection in all four F2 populations, which was newlinefurther confirmed in backcross and F3 populations indicating the role of duplicate dominant gene newlineinteraction. Correlation and variability were studied for yield, A. flavus seed colonization and infection newlinein F3 generations for identification of superior lines with resistance. Higher magnitude of GCV, PCV newlineand high heritability coupled with high genetic advance over mean was observed for resistance to A. newlineflavus seed colonization, pod yield and kernel yield in all the four crosses. Five promising resistant F3 newlineprogenies (Line no. 10, 18, 318, 246 and 15) from four crosses as they recorded less than 11.5 and#956;g/kg newlineaflatoxin content for seed coat and cotyledon resistance are potential source for aflatoxin resistance newlinealong with better yield traits compared to checks. newline