Evaluation of the influence of abiotic environmental factors on the cob structure elements formation of sweet corn cultivar samples in the Saratov Region

For successful cultivation and production of sweet corn (Zea maуs var. saccharata) in the risk farming zone, a detailed study of the adaptive capacity of new cultivars and hybrids is necessary. The objective of the research was to evaluate 47 cultivar samples of sweet corn based on the response of quantitative traits of the cob to the impact of abiotic environmental factors in the conditions of the Right Bank of the Saratov Region (arid steppe zone, continental climate of temperate latitudes, soils – southern black earth). The studies were carried out in 2021–2023. The vegetation periods from the second ten days of May to the second ten days of September were characterized by close values of the hydrothermal coefficient (HTC): 2021 – 0.62, 2022 – 0.75, 2023 – 0.69, but differed significantly in the distribution of precipitation and air temperature by months. As a result of the research, the share of influence of the factors “genotype”, “year”, their interaction, as well as an unaccounted factor on the variability of the studied characteristics of sweet corn cultivar samples was revealed. It has been established that the variability of the cob diameter and the number of grains in a row were influenced by the “year” factor to the greatest extent (46.48 and 37.57 %, respectively); the variability of cob length, rows number and the number of grains per a cob – by “genotype” factor (55.70; 54.53 and 36.49 %, respectively); grained part of a cob – by the factors interaction (32.87 %). There have also been identified the samples having steadily high average values by the “number of grains per a cob” indicator over all three years of the experiment: ‘Tsukerka’, k-4455, k-4471, k-4840, k-1976, k-5811. The greatest number of genotypes had an average resistance degree to environmental influence by the “ecological plasticity” indicator Hi (S. P. Martynov, 1989). Among them the most stable were ‘Uslada’, k-4475, ‘Zabava’, k-4468, k-4456, k-5768, k-5467, k-103. In future, they should be used in topcrossing for evaluation of combining ability.