Study of the dependence of yield of wheat and alfalfa on water supply to ensure efficient use of water resources of Azerbaijan

Abstract

The aim of this survey was to study water consumption and development of the reasonable irrigation modes of the wheat and alfalfa according to the optimal water–soil–yield ratio. In the first experiment on the sandy and loamy-sandy soils, nine irrigations of the annual alfalfa with the total rate 4338 m3/ha in the first mode, 3700 m3/ha in the second mode, and 3048 m3/ha in the third mode and eight irrigations of the biennial and triennial alfalfa in the modes, respectively, 5842, 4927, 4091 m3/ha were carried out. The fourth mode was nonirrigated plot. The yield of the annual alfalfa in the first irrigation variant (75% of the minimum moisture capacity) was 32.8% more than in the second and 45.8% more than in the third mode, and the yield of the biennial and triennial alfalfa was 12.6 and 27.1%, respectively. The decade values of the biological water consumption coefficients of the alfalfa in May–September made 0.61, 0.46, 0.45, and 0.18 in the first, second, third, and fourth variant, respectively. In the second experiment on the medium-weight loamy and clayey soils, two irrigations of the winter wheat and three irrigations of the alfalfa with the total rate 1985, 1689, 1389, and 1091 m3/ha in the first, second, third, and fourth irrigation modes, respectively. The yield of the winter wheat in the first variant (75% of the maximum moisture capacity) was 2.1% more than in the second mode, 4.5% more than in the third mode, 8.92% more than in the fourth mode, and 36% more than on the nonirrigated plot (the fifth variant). The yield of the alfalfa in the first irrigation mode (75% of the minimum moisture capacity) was 4.7% higher than in the second mode, 8.5% higher than in the third, 13.9% than in the fourth, and 30.8% than in the fifth mode.