GENETIC STUDIES ON HEAT TOLERANT LINES OF TOMATO (Lycopersicon esculentum, Mill)
Loading...
Files
Date
1992-03-24
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
MAHATMA PHULE KRISHI VIDYAPEETH RAHURI, 413 722 DIST - AHMEDNAGAR, Maharashtra State (India.)
Abstract
The performance of 28 Fl hybrids of tomato obtained by crossing eight parents in diallel analysis (Without reciprocals) was studied during summer 1986-88 at Department of Horticulture, Mahatma Phule Agricultural University, Rahuri., When the average maximum minimum temperature ranged between 36.17 to 17.93 °c respectively, and average maximum and minimum relative humidity was 62.55 and 29.06 per cent respectively. The nature and magnitude of heterosis, combining ability, nature of gene action and heritability were studied for seventeen characters. The hybrid combinations 3x4 and 4x7 were the highly heterotic combinations and recorded significantly high heterosis over better as well as top parent for fruit yield and fruit number per plant besides many other desirable characters. Considering the over all performance it may be concluded that the hybrid combinations 3x4, 4x7, 2x6, 1x4 and 2x4 exhibited the conspicuous yield in that order and were also most promising in respect of other economic characters. The hybrid combinations exhibiting very high yield per plant do have either both or one of the parent with high yielding ability and good or average gca effects for yield and some yield contributing characters like the number of fruits per plant, number of fruits per cluster, average weight of fruit, and per cent fruit set. The components of variance due to gca and sea were significant for all the characters studied. Highly significant gca and sea effects were observed for all the characters studied. The magnitude .:•:' -;ca variance was higher than sea variance for number of iocules per fruit suggesting the additive gene action, where as the variance due to sea was predominant for the characters plant height, number of primary branches, «tays for 50% flowering, flowers per cluster, fruits per cluster, fruit set percentage, number of fruits per plant, average weight of fruit, marketable yield per plant, unmarketable yield per plant, total yield per plant, polar diameter of fruit, equatorial diameter of fruit, total soluble solids, acidity percentage and number of seeds per fruit suggesting non-additive gene action. The narrow sense heritability estimates were iow for plant height, days for 50% flowering, flowers per cluster, fruits per cluster, fruit set percentage, fruits per plant, marketable yield per plant, unmarketable yield per plant, total yield per plant, equatorial diameter of fruit and number of seeds per fruit, where as the characters number of primary branches, average weight of fruit, polar diameter of fruit and total soluble solids exhibited medium heritability estimates. However the characters acidity percentage and number of Iocules per fruit recorded high heritability estimates. The overall appreciation of the data revealed that the parent 4 was the best general combiner where as the hybrid combination 3x4, 4x7, 2x6 and 1x4 recorded the highest yield and were highly promising in respect of other desirable characters under prevailing high temperature climatic condition.
Description
Keywords
null