1. KAUTIR (Kerala Agricultural University Theses Information and Retrieval)
Permanent URI for this communityhttp://localhost:4000/handle/123456789/1
Browse
2 results
Search Results
Item Genetic analysis of segregating generation of inter varietal crosses in greengram(Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 1999) Ebenezer Babu Rajan, R; Wilson, DThe research programme was carried out at the Department of Plant Breeding and Genetics, College of Agriculture, VelIayani during rabi season 1998-99, with the objective of identifying superior progenies in the F2 generation for yielding ability and nitrogen fixation 'potential. Seven parents and F 2 progenies of their 21 crosses of greengram were evaluated, adopting a randemised block design with three replications. The data collected for thirteen quantitative characters were analysed statistically. The genetic parameters, correlation and path coefficients were studied and a selection index was formulated to identify superior genotypes. The treatments showed significant difference for all the characters. High genotypic coefficient of variation was observed for weight of nodules in the root at 50 per cent flowering, dry weight of plants at maturity, nitrogen content of plants at maturity and grain yield. High heritability coupled with high genetic advance was observed for weight of nodules in the root at 50 per cent flowering followed by dry weight of plants at maturity, grain yield, number of pods, number of cIuslters per plant, harvest index, hundred grain weight, number of secondary roots at maturity, plant height and shoot/root ratio indicating additive gene action and reliability of these characters during selection programme for crop improvement. High positive genotypic correlation for number of pods per plant followed by number of clusters per plant, harvest index, plant height, hundred grain weight and number of seeds per pod indicated selection based on one or more of the above components may result in the improvement of grain yield. The path coefficient analysis revealed high positive direct effects of number of pods on grain yield. In addition hundred grain weight and number of seeds. per pod also showed positive direct contribution to grain yield. A selection index was constructed based on grain yield per plant and eight yield contributing characters identified through correlation and path analysis. Based on the selection index one of the parental varieties CoGG-902 ranked first followed by Pusa-9333 x NDM-88-14, Pusa-9333, KM-1285 x CoGG-902 and IlPRM-3 x LG-444 were identified as superior for yielding ability and nitrogen fixing potential.Item Genetic analysis of greengram genotypes for shade tolerance(Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 1998) Rajeswari, A; Kamalam, NAn investigation was carried out to evaluate the shade tolerance potential of 25 genotypes of green gram under partially shaded coconut gardens in the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani. The genotypes were evaluated in a randomised block design with three replications and observations were recorded for nineteen quantitative characters. The genetic parameters, correlation and path coefficients were studied and a selection index was formulated to identify superior genotypes. The genotypes showed significant differences for all the characters except incidence of pod borer Measurement of periodical shade intensity did not show significant difference among the plots which indicated the prevalence of uniform shade. High genotypic coefficient of variation was observed for leaf area index (flowering) followed by number of abnormal, oblique, unfilled pods, LAI (pod formation), pod clusters per plant and pods per plant. High heritability coupled with high genetic advance was recorded for pods per plant, LAI at flowering and pod formation and pod clusters per plant indicating additive gene action. Correlation studies indicated that pods per plant followed by branches per plant, clusters per plant, photosynthetic efficiency (flowering) and LAI (flowering) showed strong positive correlation with grain yield whereas days to blooming, days to first harvest and grains per pod recorded negative correlation. The path coefficient analysis revealed high positive direct contribution of pods per plant to grain yield per plant. In addition, pod length and plant height also showed positive direct contribution to grain yield per plant. A selection index was constructed based on grain yield per plant and 9 yield contributing characters identified through correlation and path analysis. Five top ranking genotypes viz. IIPRM 3, MGG 314, RMG 353, Ganga 4 and LGG 460 were identified for cultivation under partially shaded condition of coconut garden and for further breeding programme.