PALMEIRA, Irlan Victor de Sousa.
Résumé:
In subtropical and tropical regions, Vigna beans are considered one of the most important and
strategic food sources. In the Northeast region, due to seasonal changes in rainfall, with
changes in the availability of water in the soil, in this region the proper management of
resources is essential in order to guarantee the sustainability of the production system. Thus,
the objective of the present work was to evaluate the gas exchanges and production
components of Vigna cv. BRS Marataoã cultivated under water deficit management strategies
and potassium fertilization. A randomized block statistical design was used, in a 5 × 5
factorial scheme, with three replications, with the treatments being defined according to the
five potassium fertilization doses (50, 75, 100, 125 and 150% of K2O) associated with five
water deficit management strategies in the different phenological stages of the crop. The dose
of 150% K2O, in Vigna bean plants, intensifies the negative effects of water stress, reducing
stomatal conductance, pod length, pod weight and total number of beans in all phenological
stages. The irrigation management of Vigna bean plants, with 50% of the ETr, did not cause
significant difference for the instantaneous efficiency in the use of the water between the
studied phenological phases. Vigna beans fertilized with 50% of the recommended dose of
K2O had the lowest CO2 assimilation rates when subjected to water stress in the phenological
stages.
