EVALUATION OF COTTON (Gossypium hirsutum L.) GENOTYPES FOR HEAT TOLERANCE
KrishiKosh
View Archive InfoField | Value | |
Title |
EVALUATION OF COTTON (Gossypium hirsutum L.) GENOTYPES FOR HEAT TOLERANCE
|
|
Creator |
ASHA, R
|
|
Contributor |
LAL AHAMED, M
|
|
Subject |
cotton, yields, genotypes, sowing, genetics, tolerance, biological phenomena, gossypium hirsutum, planting, heritability
|
|
Description |
The present investigation was carried out during kharif 2011-12 with 40 genotypes of cotton (Gossypium hirsutum L.) at Agricultural College Farm, Bapatla to elicit information on heat tolerance of cotton genotypes using cellular membrane thermostability and enzyme viability along with the variability, heritability, genetic advance as per cent of mean, character association and the magnitude of direct and indirect effects of 14 yield component traits on seed cotton yield plant-1 viz., plant height, days to 50% flowering, number of monopodia plant-1, number of sympodia plant-1, number of bolls plant-1, boll weight (g), seed index (g), lint index (g), ginning out-turn (%), 2.5% span length (mm), micronaire (10-6g/in), bundle strength (g/tex), uniformity ratio and fibre elongation (%). The genotypic coefficients of variation for all the characters studied were less than the phenotypic coefficients of variation indicating the masking effect of the environment. High heritability coupled with high genetic advance as per cent of mean was observed for characters like number of monopodia plant-1, number of sympodia plant-1, number of bolls plant-1, boll weight, seed index, lint index, micronaire and seed cotton yield plant-1 indicating the predominance of additive gene action and hence, direct phenotypic selection may be useful with respect to these traits. The correlation and path coefficient analyses together indicated that number of bolls plant-1 and boll weight had significant positive and positive direct effects on seed cotton yield plant-1 indicating the existence of true relationship among these characters and their exploitation in selection programmes. In the heat tolerance studies, cellular membrane thermostability and enzyme viability clearly indicated the genotypic differences for thermotolerance. The mean relative electrical conductivity values showed gradual increase from 32.06 at 250C to 84.15 at 500C indicating higher temperatures had direct effect on the leakage of fluids from the cells and higher levels of cell injury. The dehydrogenase enzyme viability was reduced with the increase in the temperature from 300C and 500C. The genotypes L788, RAH 912 and Pee Dee 0113 showed high levels of heat tolerance in both the experiments at 500C and these genotypes can exploited in the breeding programmes for heat tolerance. This study clearly indicates the use of cellular membrane thermostability and enzyme viability assay for assessing heat tolerance in cotton |
|
Date |
2016-06-22T11:44:50Z
2016-06-22T11:44:50Z 2012 |
|
Type |
Thesis
|
|
Identifier |
http://krishikosh.egranth.ac.in/handle/1/67671
|
|
Language |
en
|
|
Relation |
D9403;
|
|
Format |
application/pdf
|
|
Publisher |
ACHARYA N.G. RANGA AGRICULTURAL UNIVERSITY
|
|