DIRECT SOWING IMPROVES CHLOROPHYLL CONTENT OF SILAGE MAIZE FULLY IRRIGATED WITH RECYCLED WASTE WATER BY INCREASING WATER RETENTION IN THE SOIL

Abstract

Increasing fresh water shortage has revealed the use of waste water in agricultural irrigation, deficit irrigation approaches and integrated management of soil moisture with tillage-sowing practices. The crop productivity in the irrigated conditions is directly controlled by photosynthetic activities. Therefore, the effects of the irrigation with recycled domestic waste water at different irrigation water levels (100%, 67% and 33%), compared to full irrigated fresh water, on the chlorophyll content of silage maize and surface soil moisture in conventional tillage and direct sowing conditions were examined in the irrigation periods of two experimental years (2020 and 2021). The soil moisture was determined by 1.5% higher in direct sowing than in conventional tillage, and the chlorophyll content in full irrigation with waste water and the direct sowing was found by 4.9% and 1.9% higher than in full irrigation with fresh water and conventional tillage, respectively. However, chlorophyll content decreased by 20.7% and 34.0% at 33% and 67% deficit irrigation with waste water compared to full irrigation with waste water. The significant (p<0.01) linear correlation between the soil moisture and chlorophyll content showed that chlorophyll content can be managed with the soil moisture. It can have concluded that full irrigation with waste water in the direct sowing can be recommended with positive effects on the conservation of fresh water resources, effective managing soil moisture, thus saving irrigation water, increasing chlorophyll content and crop productivity.