Dual crop coefficient of common bean in Tangará da Serra, Mato Grosso

Coeficiente dual de cultivo do feijoeiro em Tangará da Serra, Mato Grosso

ABSTRACT

This study aimed to determine the dual crop coefficient of common bean ( Phaseolus vulgaris L.) for Tangará da Serra-MT, Brazil. The study used the FAO-56 dual k_c method, dividing the k_c into soil evaporation coefficient (k_e), determined in microlysimeters, and basal crop coefficient (k_cb), determined in weighing lysimeters. The study was conducted from July 10 (sowing) to October 6, 2014 (harvest), using the common bean cultivar 'BRS Estilo' and a sprinkler irrigation system with a coefficient of uniformity greater than 80%. The total rainfall and irrigation during the crop cycle (84 days) was 524.8 mm; the potential evapotranspiration (ET_o) estimated for the period was 327.9 mm, whereas the crop evapotranspiration (ET_c) accumulated during the cycle, determined in lysimeters, was equal to 477.5 mm. The k_cb values determined for the initial, full development and final stages were 0.32, 1.10 and 0.81, respectively, while for k_e, the respective values were 0.85, 0.40 and 0.53.

Key words:
Phaseolus vulgaris; basal crop coefficient; evaporation coefficient; irrigation