Distribution of Gossypol Glands on Cotton (Gossypium hirsutum L.) Genotypes

Abstract

Knowing the distribution of gossypol glands in cotton will help to improve advanced cultivars with great economic return. The aim is to compare cotton genotypes for the number and the distribution of gossypol glands found in different plant parts and to determine the genotypes which contain more gossypol glands in their vegetative parts but little or none in their seeds. The intensity and the greatness of the gossypol amount is an important part of defending against plant insects and diseases. Randomized complete block design with two replications was applied at the Agricultural Research Institute of Kahramanmaraş during 2006-2007. Thirty seven cotton genotypes belonging to Gossypium hirsutum L. species were the plant material. The number of gossypol glands on stem, boll walls (carpels), leaves and seeds were visually counted and ranged from 0 to 142 per cm2 for stem, 0 to 135 per cm2 for leaf, 0 to 85 per cm2 for boll wall and 0 to 16 per mm2 for embryo (kernel). Number of gossypol glands varied for the genotypes and years but this variance was too low in some genotypes. Genotypes ‘Acala Royale’, ‘Acala Prema’, ‘Deltaopal’ and ‘Carmen’ had relatively more gossypol glands on their vegetative parts but less in their seed. Measured parameters were positively and significantly correlated to each other. Correlations for number of gossypol glands between stem and leaf (r=0.77**), boll wall (r=0.65**) and seed (r=0.32**) were significant.