关键词: 棉花, 噻苯隆, 植物生长延缓剂, 生长发育, 产量

Abstract: To explore the regulatory effects of foliar application of thidiazuron in combination with different plant growth retardants on the growth，development，and yield of cotton，a field experiment was conducted from July to October 2022 in Tuanjie Village，Hailou Town，Shaya County，Xinjiang.Xinluzhong 84 was chosen as the test cotton variety. Thidiazuron at 0.1% concentration was used as the main agent，combined with chlormequat chloride（W1），calcium prohexadione（W2），uniconazole（W3），and flurprimidol（W4），with water serving as the control group（CK）.A randomized block design was employed，with a spray application before and after chemical topping，to analyze their effects on cotton agronomic traits，dry matter accumulation and distribution，leaf area index，SPAD value，and yield.The results showed that the W3 treatment performed the best across all measured indices. Specifically，at the boll opening stage，compared to CK，plant height，plant width，the length of the 3rd fruiting branch，the length of the 7th fruiting branch，and leaf branch length in the W3 treatment decreased by 1.23%，3.14%，10.96%，11.72%，and 18.92%，respectively；at 30 days after treatment，the SPAD value and the dry matter accumulation of buds and bolls increased by 2.05% and 9.98%，respectively，the proportion of dry matter in reproductive organs increased by 7.61%，and the leaf area index increased by 10.85% compared to CK；the number of bolls per plant and seed cotton yield increased by 11.28% and 11.23%，respectively，compared to CK.In conclusion，application of 0.1% thidiazuron 450 mL/ha + 5% uniconazole 75 g/ha before and after chemical topping can effectively suppress cotton indefinite growth，enhance leaf area index and leaf SPAD value，promote reproductive growth in cotton plants，increase the number of bolls per plant，and significantly increase cotton yield.

Key words: Cotton, Thidiazuron, Plant growth retardant, Growth and development, Yield