Water consumption and yield of corn hybrids of different ripeness groups in permanent crops under drip surface irrigation

Abstract

Goal. To determine the parameters of the soil water regime and the yield of corn hybrids of different FAO groups in the conditions of the Steppe of Ukraine with permanent crops and drip surface irrigation. Methods. Field experiments were conducted during 2021–2025 in the Institute of Climate-Smart Agriculture of NAAS in the agroecological zone of the Southern Steppe of Ukraine (vil. Naddniprianske, Kherson oblast). The soil of the experimental site was dark-brown middle-carbonaceous slightly saline on carbonate loess, typical for the irrigated zone of Southern Ukraine. Hybrids of Ukrainian selection, listed in the State Register of Plant Varieties of Ukraine, were used: the early-ripening Stepovyi (FAO 190), the mid-early Skadovskyi (FAO 290), the mid-ripening Askaniia (FAO 320), and the mid-late Vira (FAO 430). A microbiological preparation of insect-fungicidal and growth-stimulating action was used in the plant protection system. The active basis of the drug was the mycelium, spores of the fungus from the genus Trichoderma and rhizospheric bacteria of the genus Pseudomonas with a titer of at least 2.0•1010 CFU/sm3, as well as biologically active substances that form producer strains (Trychopsyn BT). The chemical synthetic insecticidal preparation Bi 58 (active substance — dimethoate, manufacturer — BASF) and the fungicide Abacus (BASF) were used. As a chemical ameliorant, gypsum (CaSO4•2H2O) was introduced in a dose of 5 t/ha. Watering was carried out by surface drip irrigation while maintaining pre-watering soil moisture in a layer of 0–50 cm at the level of 80% HB. Results. The lowest water consumption coefficient was in the middle early Skadovskyi hybrid for the use of integrated plant protection and chemical ameliorant, both at the beginning of the 5 years of permanent crops, and in the final years (320.64 and 313.12 m3/t, respectively). A particularly noticeable increase in water consumption was observed in the absence of protective equipment and ameliorants in the final years of permanent crops compared to the original. In Askaniia and Vira hybrids, water consumption increased, respectively, by 237.11 and 347.16 m3 of water to form 1 ton of grain, which almost coincides with the water consumption coefficient in the mid-early Skadovskyi hybrid. Conclusions. The use of permanent corn crops in the conditions of the Southern Steppe of Ukraine under drip surface irrigation is possible without a significant decrease in grain yield under the conditions of the use of integrated plant protection from harmful organisms, the introduction of chemical ameliorant, and the use of corn hybrids adapted to permanent crops.