Study of Heterosis and Screening of Table Pea for Powdery Mildew Resistance Using Molecular Marker

Abstract

The present investigation was carried out to identify the promising single cross and resistance hybrids in pea based on combining ability and heterosis analysis for seed yield and yield contributing characters and screening for powdery mildew resistance using molecular marker during rabi season 2018-2020. The eight diverse genotypes of table pea were crossed in half diallel fashion to generate 28 F1 crosses and these 28 F1s were evaluated along with parental lines. At morphological level, ANOVA showed significant variation for all traits indicating greater variability in germplasm studied. High estimates of genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) were observed for seed yield per plant, number of pods per plant which indicated that high degree of variability in these characters and suggested that possibility of yield improvement through selection of this trait. High heritability coupled with high genetic advance observed for plant height, seed yield per plant, number of pods per plant, length of first fruiting node, days to 50% flowering, number of first fruiting node, length of pod and number of seeds per pod. Hence, that characters obtained high heritability and high genetic advance could be used for selection will be effective for these traits. Based on correlation coefficient, Seed yield per plant showed highly significantly positive correlation with number of pods per plant followed by length of first fruiting node, number of seeds per pod, days to 50% flowering, plant height, width of pod, length of pod and number of first fruiting node at both genotypic and phenotypic level. Thus, it can be inferred that selection based on any one of these characters either alone or in combination, will result in identifying high yielding strains. Path coefficient at phenotypic and genotypic level revealed, high positive direct effect by number of pods per plant, number of seeds per pod and days to 50% flowering towards seed yield. The parents AP-3, PC-531 and AP-1 showed significantly high positive GCA effect for seeds yield per plant and they can be used as good general combiners for seed yield. The crosses Kashi Nandini x PC-531showed the highest SCA effects, can be used as best specific combination for seed yield per plant. Arkel x VL-7 and Arkel x PMR-53 exhibited maximum significant positive heterosis over better parent and mid parent respectively, for seed yield. Based on screening for powdery mildew resistance through SCAR and SSR markers, the genotypes PMR-53, Kashi Nandni, kashi Uday, VL-7, AP-1 and hybrids PMR-53 X AP-1, VL-7 X PC-531were found resistance to powdery mildew which could be further used in breeding programme for the development of resistance genotypes. SSR Markers (AD273 and AD141) gave polymorphism between resistant and susceptible parents as well as hybrids and further these primers can be used for differentiating resistance and susceptible genotypes.