Influence of various pre-irrigation thresholds of soil moisture on growth and development of grain maize on three growing seasons

Abstract

The research goal is to study the effect of different pre-watering soil moisture thresholds on the growth and development of grain maize. The research was conducted in 2023 and 2024 on the experimental plots of the Biryuchekutskaya Vegetable Breeding Experimental Station located in the City of Novocherkassk of the Rostov Region. The soil in the study area was ordinary chernozem. The experiment included 5 variants: Variant 1 - pre-watering threshold 70-70-70% of the lowest moisture capacity (control); Variant 2 - 70-80-70% of the lowest moisture capacity; Variant 3 - 80-80-70% of the lowest moisture capacity; Variant 4 - 80-80-80% of the lowest moisture capacity; Variant 5 - 80-85-80% of the lowest moisture capacity. Watering was carried out by drip irrigation. At the current stage of the obtained results evaluation, the studies on the dynamics of leaf surface area (LSA), linear growth (LG) and yields depending on the pre-watering threshold of soil moisture are presented. On average, the highest values of leaf surface area and linear growth were recorded in Variant 5. For example, at the boot stage, the average LSA in Variant 5 reached 78.31 thousand m² ha which was by 13.59 thousand m² ha higher than in the control. The linear growth of plants was also maximum in this variant: at the boot stage, it reached 219.68 cm which was by 14.51 cm higher than in the control. The highest yield was obtained in Variant 5 and amounted to 12.2 t ha which was by 3.7 t ha (32.05 %) higher than in the control (8.5 t ha). The Variants 2, 3 and 4 also showed yield gains by 29.15, 25.5 and 27.7%, respectively, compared to the control. On the basis of field studies it was found that the use of drip irrigation with pre-watering soil moisture threshold, Variant 5 was the most effective for increasing the yield of grain maize.