1. KAUTIR (Kerala Agricultural University Theses Information and Retrieval)
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Item Studies on heterosis and combining abilities with respect to important economic traits in Capsicum annuum, L.(Division of Agricultural Botany, College of Agriculture, Vellayani, 1981) Manikantan Nair, P; Mary K GeorgeSixty three varieties of Capsicum annuum representing different agroclimatic regions of the country constituted the base material of the study. Based on yield potential , adaptability and tolerance to leaf curl complex disease, thirty varieties were selected for subsequent studies. Comprehensive genetic studies including estimation of genetic parameters, cause effect relationship by path coefficient analysis, genetic divergence by Mahalanoble D2 statistic and a nine parent diallel analysis to causes the combining ability, to unravel the pattern of inheritance and also to examine the level of heterosis manifested with respect to eighteen economic characters including four nutritiveand quality attributes namely Vitamin A, Vitamin C, Capsaicin and Oleoresin content were conducted during the year 1976-79. Analysis of plot means exhibited highly significant differences among varieties except for Capsaicin content. The high degres of variability in economic attributes offers scope for recombining desirable genes from different varieties.Item Genetic analysis in red gram (Cajanus cajan L.)(Department of Agricultural Botany, College of Horticulture, Vellanikkara, 1990) Achamma Oommen; Narayanan Namboodiri, K MThe research project "Genetic analysis in red gram" was carried out in the College of Horticulture, Kerala Agricultural University, Vellanikkara, Trichur during the period 1985-90. A 5 x 5 diallel cross, excluding reciprocals conducted in red gram revealed the predominance of additive gene effect for all the characters except days to first flowering. The combining ability analysis showed PLA-550 as the best general combiner; and the F 1 of the cross UPAS-120 x I.C. 15708 to have good specific combining ability. Negative heterosis over both the parents was exhibited by UPAS-120 x I.C. 15708 and PLA-550 x PLA-600 for days to first flowering and days to maturity which showed that early maturing segregants could be obtained from these crosses. The same crosses showed relative heterosis for yield also. The analysis of generation means by using six parameter model revealed the importance of both additive and dominance gene effects in the expression of most of the characters. Additive x additive and dominance x dominance effects showed influence in the expression of the characters. Among the components of variances dominance variance was higher for most of the characters. Heritability in narrow sense was found to be low. Number of clusters per plant and number of pods per plant were highly correlated with yield in parents, F 1 's and F2's. As the yield and yield components in the present study were under all the three types of gene action viz., additive, dominance and epistasis, reciprocal recurrent selection procedure seems to be the best suited method of breeding for improvement of this crop.