Gypsum improves maize productivity of a saline-sodic affected Lixisol

Abstract

The study aims to improve the yields of maize (Zea mays, L.) on a saline-sodic affected Lixisol by using gypsum as amendment and clean water for irrigation. A split-split-plot experimental design with four replications was used. The studied factors included: soil degradation level, irrigation water quality and gypsum rate application. The yields and yield components of maize were assessed as well as nutrient uptakes. The linear mixed effects model was used for data analysis. The results showed that clean water use compared to wastewater increased the grain yield (51%), the P (83.4%) and K (18.4%) exported by straw and the N (54.7%) and P (48%) exported by grains in the highly degraded soils. The high increases in straw (50%) and grain (73%) yields and in the N, P and K uptake (60%) were obtained subsequently to gypsum application in highly degraded soils. Gypsum application to plots irrigated with wastewater induced a twofold increase in maize straw yield in low degraded soils and a fivefold and twofold increases in maize straw and grain yields in highly degraded soils comparatively to the increases observed with the same gypsum rates application to these soils irrigated with clean water.