Productivity of winter wheat (Triticum aestivum) as influenced by fertilizer rates in rainfed fields of south Kazakhstan

Today, the need for grain is increasing every day due to the growing human population on the planet. At the same time, global climate change has a negative impact on grain production. In the conditions of the south of Kazakhstan, the main limiting factor of agricultural crops is soil moisture, since during the growing season there is an insufficient amount of atmospheric precipitation, and the moisture reserve in the soil due to autumn-winter precipitation does not satisfy the water demand of crops. It was found that the highest yield of winter wheat grain (37.7 c/ha) on average over two years of research was formed on the variant with simultaneous application of phosphorus fertilizers at the rate of P₄₅ kg/ha with direct sowing and feeding with nitrogen fertilizer at the rate of N₇₀ kg/ha in early spring periods in the tillering phase of winter wheat, that is, the grain yield increased 2.9 times in comparison with the background without fertilizers. By optimizing the phosphate regime of winter wheat with the introduction of nitrogen fertilizers during the period of their greatest need in the tillering phase, it will balance the regime of their nutrition.Therefore, an experiment was conducted during 2019-2020 year at LLC «South-west Research Institute of Livestock and Crop Production» (South Kazakhstan) to determine the norms and terms of the introduction of mineral, micronutrient fertilizers and plant growth stimulants of wheat and the peculiarities of the soil and climatic conditions of the south of Kazakhstan. Winter wheat (cv. Glassy 24) in the conditions of rainfed agriculture in the south of Kazakhstan. During the period of the laying of productive organs in the phase of booting, stalking and formation of winter wheat grain, the reserves of productive moisture were good and fully satisfied the need of winter wheat for moisture in the indicated growing periods of plants, as a result, a consistently high yield of winter wheat grain was formed for rainfed conditions in the south of Kazakhstan.