Genetic Associations under Aphids and Rosette Stress in Groundnut (Arachis hypogaea L.)

Groundnut production is largely constrained by biotic stresses with groundnut rosette virus disease seriously contributing to losses in yield in Nigeria and sub Saharan Africa. This study was conducted to understand performances and correlations between aphid resistance, rosette resistance and other quantitative characters. Two aphid resistance, one rosette resistance, one aphid susceptible and one rosette susceptible lines were used as parents to develop F1s, F2s, BC1P1 and BC1P2. The seventeen generations obtained were evaluated along with three checks in three replications using randomized complete block design. The F1 generations had higher mean performance compared to the parents suggesting heterosis. The segregating generations (F2s, BC1P1 and BC1P2) had mean values higher or lower than the parents due to transgressive genes. The genotypic correlation coefficients in contrasting magnitudes and directions exceeded those of the corresponding phenotypic correlation coefficients for most of the character pairs indicating that the correlations were more genetic than environmental in the three sets of crosses studied.