Coeficientes hídricos para o inhame (Dioscorea cayennensis Lam.). II - Fração de esgotamento da água disponível.

Abstract

The work was conduted to study the effect of soil water content on the yam production. Four trataments (A, B, C and D) with tree replicates, eleved the moisture of the soil to field capacity, during the yam growth period (90 to 180 days after sown field) in irrigation turns of 3, 5, 7 and 9 days, respectively. The soil water content was monitored, before the irrigation, throughout a neutron probe. The moisture stress decreased yam yields (tuber-production and seed-tubers). The irrigation every 7 days was the best tratament. The work recommend a soil water depletion fraction of 0.40.