Assessment of the effect of high temperature on the yield weight of cotton varieties in the conditions of the Bukhara oasis

Аннотация

The article presents data on the change in CITATION crop mass as a result of the effect of high temperature Boltayeva Zarina Azamatovna. (2025). Assessment of the effect of high on cotton varieties. During the experiments, the yield of temperature on the yield weight of cotton varieties in the conditions of the Bukhara oasis. The American Journal of Agriculture and Biomedical cotton varieties was noted to varying degrees as a result Engineering, 7(04), 18–21. of the effect of high temperature. It was determined https://doi.org/10.37547/tajabe/Volume07Issue04-04 that the difference in crop mass under the effect of high temperature depends on the individual and biological characteristics of the plant. COPYRIGHT © 2025 Original content from this work may be used under the terms of the creative commons attributes 4.0 License. Keywords: Cotton, heat stress, high temperature, crop weight, pod count, pollen. Introduction: Increasing global climate variability is threatening cotton production worldwide through extreme temperatures, drought stress, and rainfall. These stresses have resulted in a reduction in crop yields of more than 50% worldwide. These abiotic and multiple biotic stresses have a significant impact on cotton production, resulting in reduced crop yield and quality. [2-3]. During high temperature stress, cotton pollen grains lose their ability to germinate. Pollen grains are very sensitive to heat stress during ontogenesis. The length of pollen tubes is also sensitive to temperature. The length of the tubes decreased sharply when the temperature reached 34 °C and at 43 °C, approaching zero, indicating that the final yield of cotton may be affected by the stress associated with increasing temperature. A negative correlation between high temperatures and cotton fiber yield has been observed. The annual variation in cotton yield is associated with the sharp variation in temperature during the growing season (a serious problem for cotton producers). It has been observed that when the average temperature The American Journal of Agriculture and Biomedical 18 https://www.theamericanjournals.com/index.php/tajabe Engineering The American Journal of Agriculture and Biomedical Engineering exceeds 32 °C, a significant decrease in yield is METHODS observed, and there is also a strong tendency for fruit Our research was conducted in the Bukhara region. The yield to decrease after 29 °C [6]. When the Bukhara-102, Bukhara-8, Bukhara-10, Sultan and temperature exceeds the optimal range during the Andijan-35 varieties belonging to the group of medium- day, the rate of photosynthesis and carbohydrate fiber cotton varieties were used as the objects of production decreases. High night temperatures research. These varieties are currently widely cultivated increase respiration and reduce carbohydrate content, in various regions of our republic. Before conducting which leads to a decrease in various parameters (boll field experiments, non-saline-control and moderately- volume, seed set, seed number and, most importantly, strongly saline (experimental) fields were determined. fiber quality) [1-4]. The number and volume of bolls, Laboratory experiments In order to determine the effect the main components of cotton yield, are found to be of high temperatures on varieties during cotton very sensitive to temperature extremes, and they ontogenesis, experiments were conducted in laboratory significantly reduce boll retention and affect the final and greenhouse conditions at the Laboratory of cotton yield [7-8]. Ecological Physiology of Bukhara State University. All According to literature sources, heat stress negatively field experiments were carried out at the Bukhara affects seed development and is one of the main Scientific Experimental Station of the Academician M. factors reducing yield. It has been noted that small Mirzaev Scientific Research Institute of Horticulture, temperature fluctuations in the field are not sufficient Viticulture and Winemaking and at the “Furkat” farm in to reduce seed weight, but this small increase can the Kogon district. Productivity and its quality indicators significantly reduce the number of seeds per boll. To were determined based on generally accepted prevent yield losses under stress conditions, simple methods. selection procedures should be followed. A selection RESULTS AND DISCUSSION scheme can be used to conclude that reproductive The effect of temperature on the yield weight of cotton tissues are responsible for their sensitivity to varieties was also studied during scientific research. The temperature [5]. results are presented in Figure 1. The American Journal of Agriculture and Biomedical 19 https://www.theamericanjournals.com/index.php/tajabe Engineering The American Journal of Agriculture and Biomedical Engineering 2019 2020 2021 Average 50 45 40 5 3 35 - 0 3 30 : lo 25 r t n o 20 42 43.4 41.2 42.2 45.7 47.4 46.1 46.4 42.7 45.3 43.7 43.9 39.6 42.1 38.9 40.2 43.6 40.8 42.8 42.4 c 15 1