Adaptive sunflower growth techniques in the Ryazan region

The purpose of research is to study the adaptive properties of sunflower hybrids depending on the timing of their sowing when grown in the conditions of the Ryazan Region. The scheme of the field experiment, which was carried out in 2019-2022, determined two sowing dates: the second and third decades of May. The objects of research were the hybrids Imeriya KS, Codizol KL, Clarissa KL, Meridis KL, Zubella KL, Fushia KL. The climatic conditions of the Ryazan Region are favorable for the production of oilseeds. However, during the ripening period of sunflower seeds, unfavorable weather conditions (high humidity and low air temperatures) often occur, contributing to the development of diseases, lengthening the harvesting period, and increasing the cost of purchasing desiccants. In the experiment, the most adapted to the conditions of the Ryazan Region were identified sunflower hybrids Imeriya KS and Codizol KL. Their morphometric and photosynthetic parameters, as well as their yield, were significantly higher than those of other hybrids. According to the yield level, the studied sunflower hybrids can be arranged in the following row: Imeriya KS › Codizol KL › Clarissa KL › Zubella KL › Fushia KL › Meridis KL. At this sowing time, the highest values of leaf area, photosynthetic potential, net productivity of photosynthesis, diameter of anthorax and its productive part, number and weight of seeds were obtained. The maximum yield was observed in the hybrids Imeriya KS and Codizol KL, and amounted to 29.3 and 27.1 c/ha, respectively.