CREATION OF HIGH-PRODUCTIVE COTTON VARIETIES IN SOUTHERN KAZAKHSTAN

Abstract

Abstract
Background and Aim. Cotton is a strategically important crop in the agro-industrial sector of Kazakhstan; however, its sustainable development is constrained by soil degradation and increasingly frequent droughts. Therefore, the present study aimed to accelerate the development and evaluation ofresistance to abiotic stress factors in the conditions of the Turkestan region.
Materials and Methods. The studies were conducted during 2023–2025 on light sierozem soils under extreme drought conditions (temperature 4.5 ºC above the norm). 15 promising cotton varieties of the M-4000 series were evaluated. The technological properties of the fiber were determined according to international standards (micronaire, breaking load). Statistical processing was performed using the method of B.A. Dospekhov.
Results. Ten cotton varieties were identified that surpassed the M-4005 standard in terms of early
maturity by 1–6 days. The yield leaders were recorded for the lines M-4018 (43.2 c/ha), M-4003 (42.8c/ha), and M-4012 (42.5 c/ha), which is 39.6–42.6% higher than the control. Technological analysis demonstrated high fiber quality: in sample M-4015, the breaking load reached 5.0 g.f. with an optimal micronaire of 4.4 μg/inch. It was established that high productivity in the dry year was ensured by intensive boll accumulation and the weight of raw cotton per boll (up to 6.2 g).
Conclusion. The developed breeding lines M-4018, M-4012, M-4030 demonstrated high ecological plasticity and competitive fiber properties. These varieties are recommended for transfer to the State Variety Testing system and for use as heat resistance donors in hybridization programs.