Browsing by Author "Sreekumari Amma, J"
Now showing 1 - 3 of 3
Results Per Page
Sort Options
ArticleItem Open Access Comparative performance of f1 and parents in intervarietal crosses of rice(Kerala Agricultural University, 1977) Sreekumari Amma, J; Namboodiri, K M N; Mary K George; KAUThe behaviour of six characters on direct and reciprocal hybrids of two intervarietal crosses in rice was studied along with their parents and the following conclusions were drawn. There was a clear evidence of positive heterosis in plant height. The hybrids showed increase in plant height over the two parents. All the hybrids are significantly superior to both of the parents with respect to the total number of tillers produced. With regard to the number of nodes the hybrids did not show any significant difference over the parents. In the area of flag leaf the hybrids between Dee-Geo-Woo-Gen x Annapurna manifested positive heterosis while the reciprocal hybrids showed little heterosis. As regards the area of second leaf from the tip both the hybrids were not superior over the parents. But for the character of second leaf angle the hybrids were superior to their parents with reduced leaf angle. In general hybrids were better than the parents with respect to plant height, number of tillers, area of flag leaf and leaf angle.ThesisItem Open Access Correlation and path analysis in sesamum (Sesamum Indicum L.) under rainfed conditions(Department of Plant Breeding, College of Agriculture, Vellayani, 1991) Kuriakose Conil; KAU; Sreekumari Amma, JA research programme was carried out at the College of Agriculture, Vellayani with twentyfive varieties of sesamum during the rabi season of 1989, in order to identify superior sesamum genotypes possessing high oil content and to asses the relationship between yield oil content and to assess the relationship between yield and other plant characters through correlation and path analysis under rainfed conditions in the rabi uplands. The design adopted was a randomised block design with three replications and observations were recorded from randomly tagged plants on 13 plant characters and the major weather parameters. Significant differences existed among varieties with respect to six characters studied. The variety C-6 had the maximum seed oil percentage of 56.96 per cent. The variation in oil content of seeds was largely due to genotypic differences. The highest estimate of 94 per cent heritability was shown by the character oil content of seeds, while the highest genetic advance under 5 per cent selection was shown by the character number of seeds per capsule. At the genotypic level, seed yield was positively correlated with plant height, length of the capsule, breadth of the capsule, root-shoot ratio, number of seeds per capsule, days to first flowering and oil content of seeds and negatively with number of leaves per plant and number of capsules per plant. The oil content of seeds showed positive genotypic correlations with number of seeds per capsule, days to first flowering and seed yield and a negative correlation with root- shoot ratio. Path analysis technique was not found to be satisfactory to explain the direct and indirect effects of plant characters since the residual values obtained were high. The variety ACV-2 ranked first among the five varieties identified as superior genotypes at 20 per cent selection. The expected genetic gain was estimated as 37.25. The maximum amount of drymatter was produced by the variety ACV-1. The variety NPG-3 had the highest amount of proline in its leaves. None of the varieties could be regarded as a 'proline accumulating' genotype. The highest percentage of soil moisture available was at 56 days after sowing. The sesamum crop received the highest amount of 25.5 mm rainfall during the 42nd standard meterological week and the lowest amount of 1 mm rainfall during the 50th standard meterological week.ThesisItem Open Access Effect of harvesting time in seednut characters in coconut(Department of Plant Breeding, College of Agriculture, Vellayani, 1993) Vanaja, T; KAU; Sreekumari Amma, JOn the west coast of India, seednuts are being harvested during the summer months (February to May). The present investigation was mainly to know whether the nuts harvested through out the year can be used for seednut purpose in komadan. An attempt was also made to find out the effect of season on the floral characters in the two varieties. Study on the effect of season on the manifestation of the various floral characters revealed that, in both Komadan and WCT, during February to May there was higher production of bunches having proportionately more female flowers resulting in higher nut yields. The study on mother palm characters revealed that the Komadan variety exhibited superiority over WCT in number of spadices per palm per year, number of nuts per bunch and annual nut yield per palm. Correlation studies in mother palm characters revealed that the principal yield components in Komadan were number of nuts per bunch, number of bunches per season and percentage fruitset, while in WCT, high yields were the resultant effect of number of nuts per bunch, number of female flowers per spadix, number of bunches per season, total number of female flowers and number of spadices. It was also observed that in both varieties when the number of female flowers per spadix increases the retention percentage gets reduced. Most of the correlations between floral and yield traits studied were found to be homogeneous at different times of harvest in both varieties, with more homogeneity in Komadan. Study on the effect of harvesting time on seednut characters revealed that February to May (hot weather periods) is the best period for seednut collection in both WCT and Komadan. This is based on the fact that the important seednut characters like copra content per nut, kernel weight, size of nut, husked nut weight and seednut quality index were found to be at its maximum for nuts harvested during summer months in both WCT and Komadan. The Komadan variety was found to be significantly superior to WCT in four seednut characters viz., weight of kernel, copra content per nut, weight of embryo and volume of nut water. Varietal difference affected only a very limited number of correlations among seednut characters. Most of the inter correlations among seednut characters were found to be homogeneous at different times of harvest in both Komadan and WCT. In both Komadan and WCT, among the seednut characters, weight of kernel was found to be highly correlated with copra content. Oil content was not correlated with any of the seednut characters in Komadan. But in WCT, it was found to be negatively correlated with kernel weight. Among the 15 seednut characters studied, five characters viz., equatorial diameter, weight of unhusked nut, weight of husked nut, weight of kernel and oil content contributed 90 per cent of the total variation explained by the 15 seednut characters on copra content per nut, in both Komadan and WCT. In both Komadan and WCT, the very limited variability for oil content was explained by the 15 seednut characters studied. In Komadan, yield of nuts was negatively correlated with equatorial diameter of nut, weight of unhusked nut and weight of husked nut. But in WCT, yield of nuts was negatively correlated with almost all seednut characters. Based on seednut qualities, hot weather periods (February to May) were found to be the most suitable time for seednut collection in both Komadan and WCT.