Características fisiológicas e produtivas de bananeira ‘prataanã’ submetida a intervalos de irrigação e altura de emissores

Abstract

This study aimed to evaluate the productive characteristics, gas exchange and water use efficiency in banana 'Prata-Anã' clone Gorutuba under different irrigation intervals associated with different emitter heights. Therefore, a field experiment was conducted in a 2x4 factorial scheme: two irrigation intervals (daily and every two days) and four emitter heights (50, 70, 90 and 110 cm), in a completely randomized design with four replicates. The irrigation depths, applied by micro-sprinkler irrigation system, were calculated as a function of crop evapotranspiration. Gas exchanges were evaluated during the period of greatest climatic stress and the productive characteristics at the harvest. The economical water use efficiency was determined indirectly, considering the production divided by the applied irrigation depth, which was the same in all treatments. The instantaneous water use efficiency was estimated with an infrared gas analyzer in the critical climatic period. There was no interaction between irrigation intervals and emitter height. The two-days irrigation interval provided lower values of leaf temperature and photosynthetically active radiation incident on the leaf, resulting in higher fruit weight, and, consequently, higher yields and higher water use efficiency. The highest fruit weights were obtained on heights of 70 and 90 cm.