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20163
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Subject: Plant Breeding and Genetics × Start date: 2016 ×
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    ThesisItemOpen Access
    Intra-varietal variability in komadan coconut(Cocos nucifera L.) palms
    (College of Agriculture, Vellayani, 2016) SathishKumar, S; KAU; Beena, Thomas
    The project entitled “Intra-varietal variability in Komadan coconut (Cocos nucifera L.), palms" was under taken with an objective toassess the intra-varietal variability in Komadan coconut palms for yield and other attributes. The data for the investigation were collected from two field experiments during the period 2014-16. In experiment I, 50 Komadan palms in the Instructional Farm, Vellayani, were utilized as the material for the study. The highest number of leaves and spadices per year were observed in palms C9, C19, C20, C21, C23, C31, C32, and C35. The maximum number of nuts per bunch,weight of copra per year, length of leaf and number of leaflets per leaf were recorded in palm C17. The maximum number of nus per palm per year, weight of nuts per year and weight of husked nuts per year were noticed in C32. The highest weight of husked nut and nut equatorial circumference were observed in palm C19. The maximum copra content per nut and endosperm thickness were found in palm C18. The maximum coefficient of variation was recorded for number of female flowers per inflorescence. The colour of midrib was found in four different ranges from moderate olive green to moderate brown and colour of tender coconut fell into five different group. High positive correlation was recorded for number of nuts per palm per year, with number of leaves per year, number of spadices per year, number of female flowers per inflorescence, number of female flowers per spikelet and number of spikelets per spadix. The principle component analysis revealed that the first four components with Eigen valuegreater than 0.79 contributed about 92.08 per cent of the total variability. The characterssuch as weight of nuts per year, number of nuts per palm per year, weight of husked nuts per year, number of nuts per bunch, weight of nut, copra content per nut and weight of copra per year were the most important ones contributing to the overall variability. In experiment II, seedling variability among the 100 Komadan seedlings raised in the coconut nursery of Instructional Farm, Vellayani were studied. The seedling S71 showed maximum values for collar girth at nine months age, number of leaves at nine months age and twelve months after sowing. The seedling S68 was found to have maximum height and collar girth at nine months age and number of leaves at nine and twelve months age. The seedling S100 was observed to have the highest collar girth at twelve months age, number of leaves at nine months and twelve months age. The maximum coefficient of variation was recorded for number of leaves at twelve months age. High significant correlation was noted among eight morphological characters. Number of days for germination was positively correlated with number of days for splitting of leaflets and height of seedlings was positively correlated with collar girth. Number of days for splitting was negatively correlated with collar girth and height of seedlings. In the present research programme, the yield related parameters in Komadan palms expressed high variability. This variation will provide opportunities tothe breeder for utilization, conservation and further genetic improvement by selection of palms with promising yield related characters.
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    ThesisItemOpen Access
    Evaluation of superior cultures for yield and yellow vein Mosaic resistance in okra
    (College of Agriculture, Vellayani, 2016) Nikitha, J; KAU; Arya, K
    The present study entitled “Evaluation of superior cultures for yield and yellow vein mosaic resistance in okra (Abelmoschus esculentus (L.) Moench)” was carried out in the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani during 2014-2016, with the objective to identify high yielding and yellow vein mosaic resistant cultures of okra from those evolved through inter-varietal hybridization programme. Fifteen superior cultures of okra obtained from the previous project in the Department viz., VLYA 1, VLYA 2, VLYA 3, VLYA 4, VLYA 5, VLYA 6, VLYA 7, VLYA 8, VLYA 9, VLYA 10, VLYA 11, VLYA 12, VLYA 13, VLYA 14 and VLYA 15 along with two check varieties Varsha Uphar and Kiran were evaluated in a Randomized Block Design (RBD) with three replications during summer season of 2015. The analysis of variance was calculated for the traits under study viz., days to 50 per cent flowering, number of fruits plant-1, fruit weight (g), fruit length (cm), fruit girth (g), yield plant-1 (g), plant height (cm) and duration (days) and these were found to be highly significant for all the genotypes evaluated. The maximum yield was recorded by the genotype VLYA 2 which was on par with genotypes VLYA 5, VLYA 10, VLYA 11, VLYA 13 and VLYA 15 and the minimum yield was observed by the check variety Kiran. The yield plant-1 exhibited moderate GCV (18.42%) and PCV (19.05%), high heritability (94.00%) coupled with high genetic advance (36.69%). The yield plant-1 was found to be significantly and positively correlated with number of fruits plant-1, fruit length, fruit girth, fruit weight and plant height both at genotypic and phenotypic levels. Days to 50 per cent flowering and yellow vein mosaic disease incidence was found to be negatively correlated with yield plant-1. Very high positive and significant inter-correlation was noticed between height of plant and number of fruits plant-1. The path analysis showed that number of fruits plant-1 and fruit weight showed the maximum positive direct effect towards yield. The number of fruits plant-1 had high indirect effect through fruit length. The scoring for yellow vein mosaic disease and the vulnerability index revealed that the genotypes VLYA 5, VLYA 11 and VLYA 13 were resistant to the disease during all stages of crop growth. Number of white flies was found to be highest in VLYA 10 and lowest in VLYA 2. The incidence of fruit and shoot borer was also scored and five genotypes viz., VLYA 2, VLYA 4, VLYA 11, VLYA 13 and VLYA 14 were found to be immune and VLYA 3, VLYA 5, VLYA 15 and Varsha Uphar were found to be resistant. The glass house experiment of vector transmission and graft transmission was conducted for the confirmation of disease resistance and the vulnerability index was calculated to check the severity of the disease. The genotypes VLYA 5, VLYA 11 and VLYA 13 received a score ‘0’ which indicated that these genotypes were highly resistant. Hence the genotypes which obtained a vulnerability index of ‘0’ during both field evaluation and glass house experiment were confirmed to be resistant to yellow vein mosaic disease. Hence the present study revealed that the cultures VLYA 5, VLYA 11 and VLYA 13 were having high yield and yellow vein mosaic disease resistance. So these genotypes can be used for further trials before releasing for field cultivation.
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    ThesisItemOpen Access
    Varietal evaluation and genetic improvement of Anthurium (Anthurium undreanum Linden) through hybridization
    (College of Agriculture, Vellayani, 2016) Reshma, Gopi; KAU; Beena, Thoma
    The present investigation, “Varietal evaluation and genetic improvement of anthurium (Anthurium andreanum Linden) through hybridization” was carried out at Coconut Research Station, Balaramapuram, during 2014 -16, to assess the genetic variability of commercial genotypes of anthurium and improve them through intervarietal hybridization. Twenty five genotypes of anthurium were evaluated in completely randomized design with five replication to identify suitable parents with commercial qualities.There was wide variation among the qualitative as well as quantitative characters of anthurium. The number of flowers year-1 ranged from 1.2 (Lucia Pink, Mauritius Orange) to 4.8 (Cascade White and Lady Jane) and the spathe size ranged from 42.88 cm2 (Lady Jane) to 101 cm2 (Boroque). The number of suckers plant-1 exhibited high genotypic coefficient of variation and phenotypic coefficient of variation followed by anthocyanin content, pollen fertility, number of flowers year-1 and leaf area. High heritability coupled with high genetic advance found in almost all the characters except days from emergence to maturity of leaves, days from emergence to maturity of inflorescence, number of suckers plant-1 and duration of female phase. It indicates additive gene effect and improvement could be made for that character by simple selection based on the phenotypic performance. The number of flowers year-1 showed significant positive phenotypic association with characters like leaf area, spadix length and inclination of candle with the spathe. Based on the availability of pollen as well as the receptivity of stigma, sixty two crosses were attempted among the fifteen parental genotypes, out of which twenty six were successful. The percentage of candle bearing berries ranged from 0 to 100. The average number of fruits candle-1 was found to be high in the variety Liver Red and it was low in the genotypes, Vezuvious Red and Chekas. The percentage of fruit set was high in Liver Red x Dragon’s Tongue and it was low in Chikoos x Liver Red. The cross Hawaiian Orange x Dragon’s Tongue exhibited the maximum seed size among the single seeded berries and in double seeded berries, Hawaiian Orange x Chikoos found to had the highest seed size. The percentage of germination was high in Hawaiian Orange x Chikoos and low in Pistache x Chikoos. The present investigation revealed that there was wide variation in characters among twenty five genotypes of anthurium evaluated. Cross compatibility analysis revealed that the cross Hawaiian Orange x Chikoos have medium fruit set and highest seed germination among all the successful crosses.