Воднопитательные нормы и режим орошения сортов хлопчатника Бухара-6, Бухара-8 и Денов при возделывании на основные и повторные культуры

Аннотация

Subject of research: Light sierozem soils of the Kizrikdara massif in Surkhan-Shcrabad oasis, Bukhara-6, Bukhara-8 and Denov cotton varieties, fertilizer rates. Purpose of work: To study nutritive rates and irrigation regimes of the Bukhara-6, Bukhara-8 and Denov middle-fibrous varieties grown as the basic and Bukhara-8 and Denov cotton varieties as a double crops in irrigated light sierozems of the Kizrikdara massif in Surkhan- Shcrabad oasis, to give recommendations/ Method of research Scientific researches were conducted on irrigation-nutritive regimes for the Bukhara-6, Bukhara -8 and Denov varieties by “Field experiment methods” (2007) of Uzbek Scientific Research Institute for Cotton Growing (UzSRICG). The results achieved and their novelty: New regionalized middle-fibrous variety of Bukhara-6 and the perspective middle-fibrous varieties of Bukhara-8 and Denov were grown first as basic and double crops on different irrigation regimes in the light sierozems of Surkhandarya region and their optimal irrigation regimes, timings and the NPK rates were determined, also created the basis of scientific-practical values of yield increase. Practical value: The optimal antecedent moisture was 65-65-60% of less field holding moisture capacity (LFHMC) where, Bukhara-6 and Bukhara-8 varieties grown as basic; and its regular yield formed 40.0-39.6 centner (100kg) I ha by three years; also water expenditure rate formed 121.2-122.5 m3 In the Denov variety, those indications were 40.4 centner /ha and 105.5 m3 when LFHMC was 60-60-60%. There were determined that highest results were achieved when optimal NPK rates formed 250, 175 and 125 kg per hectare (kg/ha) for those cotton varieties, and determined that optimal antecedent moisture in Bukhara-8 variety was 65-65-60% LFHMC and NPK rates were 200, 140 and 100 kg/ha in double cropping, as well as, in Denov variety, those determinations were accordingly N-150, P-105 and K-75 kg/ha with the 60-60-60% of LFHMC. Degree of embed and economic efficiency: Recommendations were given by optimal irrigation and nutritive regimes for Bukhara-6, Bukhara-8 and Denov varieties, and entered in Surkhandarya farming system. Field of application: farming economics specialized in cotton growing.