Genotypic Variation in Physiological Quality of Fresh Cotton Seed

Quality seed is essential to increase cotton production in Bangladesh. For this, 43 cotton genotypes were evaluated to identify better inherent physiological seed quality. The experiment was set up at the Seed Science and Technology Unit Laboratory of Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh in May, 2009. The results showed great variation exists in seed index, seed germination percentage, electrical conductivity and seedling vigour of studied cotton genotypes. Frequency distribution suggested the majority number of the genotypes had higher values of germination percentage and seedling vigour. Electrical conductivity (EC) test of seed leachate provides the status of seed quality. The highest EC of seed leachate found in genotypes BC-0434 and BC-0432 ensuing of weak membrane while the lowest EC of seed leachate was recorded in genotype BC-0125. Cluster analysis grouped the genotypes into five distinct groups which categorized into (i) low, (ii) medium low, (iii) medium, (iν) medium high and (ν) high vigour. The genotypes BC-051, BC-0197, BC-0432, BC-0438 and BC-0252 in cluster V showed the highest germination percentage (96.20%) with the highest seedling vigour index (5064). Therefore, these genotypes could be used for genetic improvement of cotton considering higher yield with better seed quality.