The effect of moisture supply conditions on productivity of winter bread wheat, sown after various forecrops in the southern part of the Rostov region

Weather and climatic conditions determine moisture supply, which is the main factor affecting winter wheat productivity in the area of unstable moisture. The current study was carried out on the experimental plot of the laboratory for cultivation technology of grain crops of the FSBSI Agricultural Research Center “Donskoy” in 2010–2020. The soil of the experimental plot was ordinary calcareous heavy loamy blackearth (chernozem). The humus horizon was powerful up to 140 cm. The humus content was 3.9%. The purpose of the study was to establish the moisture supply of winter bread wheat when cultivated according to various forecrops. There has been found that the autumn periods in the most years of study were arid with 37% of precipitation. Winter wheat plants from September to June were provided with 70% of precipitation, with a 1022.55 of air humidity deficit and 664.7 mm of water demand. There was found that, on average over the years of study, 88% of moisture supply promoted yielding of 7.03 t/ha of winter wheat sown in weedfree fallow. In order to yield a ton of grain there was required 591.7 m3 of total moisture. The share of precipitation in this moisture consumption was 84%, and the share of soil moisture was 16%. When sown after sunflower, moisture provision was 77%, and winter wheat yield was 5.32 t/ha. In order to yield a ton of grain there was required 657.3 m3 of total moisture, which was on 65.6 m3 more than in the variant with a weedfree fallow. The share of precipitation in this moisture consumption was 96%, and the share of soil moisture was 4%.