Annual cotton (Gossypium hirsutum L. r. latifolium Hutch.) is known as a sensitive plant to oxygen deficient soil. The purpose of this work was to investigate the physiology and yield of cotton CNPA 7H cultivar, grown under greenhouse conditions and exposed to oxygen shortage, by soil flooding, at seedling stage. Two experiments were carried out and the experimental design was a randomized complete block with seven flooding periods and six replications. At the fourth day of flooding regime a decrease of 76.69% invertase activity, 77.37% of beta-amilase, and 51.10% of nitrate reductase was observed. The photosynthesis activity was affected from the first day, being reduced to 58.63% in the fourteenth day of flooding; the carbohydrates were accumulated on leaves, stem and roots. Cotton yield was reduced to 35.76% at the tenth day of flooding stress.
Gossypium hirsutum; metabolism; anoxia; relations
