Speed of growth as a criterium of drought resistance in cotton

Abstract

Selection for speed of root growth was done on seedlings for three varieties of cotton (Gossypium hirsutum L.r. latifolium Hutch) both in greenhouse and in laboratory, in order to obtain strains with better drought resistance. Of the three varieties used: Acala del Cerro, Allen 333/57 and SU-0450/8909, the latter presented always a better heritability and genetical gain. After four cycles of recurrent selection the heritability for root growth in this variety was 37% with a genetical gain of 65%. These results were obtained with adult plants and therefore it can be concluded that early selection for speed of root growth in seedlings results in longer roots in grown-up plants.