Genetic variability is a major component which helps in selecting better genotypes under different environmental conditions. Thus, this study was conducted to understand the genetic variability and its components and their trait associations of yield characters from the cross of GKVK-13 and KCG-2 that contribute to the F6 and F7 families. In an augmented block design with three checks, TMV-2, KCG-6, and KCG-2, the study was carried out at the University of Agricultural Sciences, Bangalore, in the 2017 summer and Kharif (rainy seasons). Highly significant differences between the families were found in the analysis of variance for all the characters studied in the F6 and F7 generations, indicating that there is enough variation. Furthermore, medium to high Phenotypic coefficient of variation and Genotypic coefficient of variation values coupled with high heritability and medium to high genetic advance as per cent mean observed in most of the traits showed that the majority of the attributes were controlled by additive gene activity and that there was adequate variability. In addition, phenotypic correlation coefficients depicted significant positive associations for most of the traits studied. The implications of the results are discussed. The study concludes that there was the presence of additive genes controlling most of the traits and early selection of these traits is possible for groundnut improvement in the breeding programme.

Genetic variability is major component which helps in selecting better genotypes under different environmental conditions, with this aim an experiment was conducted to understand the genetic potential, heritability, genetic advance and traits association of yield contributing characters for F6 and F7 families derived from the cross GKVK-6 × KCG-2 at the University of Agricultural Sciences, Bangalore in an augmented block design along with three checks viz., TMV-2, KCG-6 and KCG-2 during summer and Kharif 2017. Results from analysis of variance (ANOVA) revealed that highly significant differences were observed for all the characters studied. High genetic variability was observed for major yield contributing characters like the number of pods per plant (g), pod yield (g), kernel yield per plant (g), SMK% (sound mature kernel per cent), SCMR (SPAD chlorophyll meter reading) and SLA (specific leaf area) (cm2/g). Narrow difference between GCV (genotypic coefficient of variation) and PCV (phenotypic coefficient of variation) was observed for pods per plant, pod yield, SCMR and SLA and high heritability coupled with moderate genetic advance per cent mean was recorded for pod yield, SCMR and SLA indicating the involvement of additive gene action in controlling these traits. Three superior families were noticed with more pods plant-1, high pod yield plant-1, high kernel yield-1, high shelling (%), high SMK (%), high SCMR value, and low SLA value. Further, these superior families also revealed the presence of high parent offspring regression and intergeneration correlation, implying increased efficiency of selection for most of the traits considered and these were identified to be the important characters that could be used in selection for yield Keywords: GCV, PCV, Heritability, GAM, water use efficiency, Groundnut.

The foliar fungal disease late leaf spot (LLS) caused by Cercospora personata is a major and widely distributed disease. Cause substantial yield loss and in combination with the diseases increased up to 70 per cent in India. Therefore, to reduce the effect of disease and yield penalty effective chemical control mainly depends on multiple fungicide applications which are costly for resource-poor farmers and also raise environmental and health concerns. Therefore, to reduce the cost of production the development of resistant cultivars is an eco-friendly concept, with this research gap study was conducted to identify groundnut families with high yield and resistance to late leaf spot disease. From 60 F7 families of three crosses (GKVK-16 × KCG-2, GKVK-13 × KCG-2 and GKVK-6 × KCG-2 along with checks KCG-6, KCG-2 and TMV-2) which were evaluated in augmented design during Kharif 2017 in disease plot and control plot, disease screening was done using a modified 9-point scale. Disease scoring was done at 60, 90 and 120 days after sowing (pod filling stage). The disease scores were mainly based on the extent of leaf area damage. Results depicted that among the 60 families, 19 families showed consistence performance both at normal and disease plots. However, three families showed differences in the pod yield both at normal and disease plots. The families that exhibited resistance to LLS disease showed per cent yield reduction that ranged from 0-35%, and moderately resistant families exhibited a yield reduction from 35-50%, however, 50-90% yield reduction was observed in the families which showed moderate susceptibility, further more than 100% yield reduction was noticed in the families which are susceptible to LLS disease in three crosses of groundnut. High values of GCV and high PCV, high heritability coupled with high GAM were observed for PDI at 60th, PDI at 90th and PDI at 120th days after sowing in all three crosses. Among 14 superior families six, among 13 superior families eight, and from three superior families one family showed resistance to LLS disease from the cross GKVK-16×KCG-2, GKVK-13×KCG-2 and GKVK-6×KCG-2 respectively. Therefore, these identified families will be forwarded for muti-location disease and further yield stabilization.