Estratégias de manejo do déficit hídrico nas fases fenológicas de genótipos de algodoeiro colorido.

Abstract

The cotton culture is one of the most important in the world and in Brazil, standing out for having fibers of high applicability in the industry, as well as a culture with a high degree of need for manpower. Thus, the aim of this work was to evaluate the effects of water deficit in colored cotton genotypes in different phenological phases of the plant. physiology, photosynthetic pigments and the production of colored cotton feather genotypes under water deficit in different phenological phases during the different stages of plant development, under water deficit conditions. The plants were conducted in lysimeters under field conditions, at the Federal University of Campina Grande, at the Center for Science and Agrifood Technology, Campus Pombal - PB. belonging to the Federal University of Campina Grande. The experiment was carried out in a randomized block design in a 3 x 7 factorial scheme, corresponding to the combination of three colored fiber cotton genotypes with seven (BRS 'Rubi', BRS 'Topázio' and BRS 'Safira') under different water deficit strategies at different phenological stages of the crop. The plants were grown in plastic containers (drainage lysimeters), spaced 1.2 x 1.0 m, filled with the use of Neutrol Regolitic Eutrophic, with a sandy-loam texture. The physiology of colored cotton was more sensitive to water deficit in the vegetative phenological phases in isolation and successively in the vegetative / flowering and vegetative / fruiting phases. The pigments of the BRS Topázio genotype stood out among the other studied genotypes. While for the plume cotton mass it decreased with the water deficit applied in the flowering phases, and vegetative / flowering and flowering / fruiting combination, however it had greater production when the water deficit was imposed in the fruiting phase for the BRS Topázio and BRS genotypes Sapphire. The water deficit reduced the number of seeds and the total seed mass of the BRS Rubi genotypes for all phenological phases, however, BRS Topázio and BRS Safira are more tolerant to water deficit.