Studies on Gall Midge (Biotype 3) Resistance and Genetic Analysis in Rice (Oryza sativa L) Genotypes

Abstract

22 rice genotypes were evaluated for gall midge resistance and genetic analysis of yield traits during kharif, 2022 at Regional Agricultural Research Station, PJTAU, Polasa, Jagtial, Telangana. Field screening for gall midge resistance revealed highly susceptible (1 entry), susceptible (11entries), moderate susceptible (6 entries) and moderate resistance (4 entries) reaction among all tested entries.JGL 44143 (2%), JGL 44146 (4%), JGL 44147 (5%) and JGL 44088 (5%) recorded least percent of silver shoots and exhibited moderate resistance. Days to 50% flowering, plant height, effective bearing tillers/m2 and panicle length recorded low values of phenotypic coefficient of variation and genotypic coefficient of variation, whereas, 1000 grain weight recorded moderate values and percent of galls recorded high. Grain yield exhibited moderate values of PCV and high values for GCV. Grain yield, 1000 grain weight and percent galls exhibited high values of both heritability and genetic advance which can be improved with simple selection based on phenotypic performance in desirable direction. Higher inter cluster distance was noticed between clusters of III and IV (2094.45) followed by I and IV (927.52), II and IV (745.94) and II and III (525.61). Based on cluster mean values, genotypes of cluster I found to be promising for gall midge resistance and MTU 1001 (cluster II) for high yield. Crossing between genotypes of clusters I and IV could generate gall midge resistant segregants. The trait, days to 50% flowering (38.10%) contributed highest towards total divergence followed by 1000 grain weight (20.78%) and grain yield (19.91%).