Welcome to Chinese Agricultural Science Bulletin,

Chinese Agricultural Science Bulletin ›› 2023, Vol. 39 ›› Issue (6): 26-34.doi: 10.11924/j.issn.1000-6850.casb2022-0272

Special Issue: 生物技术 棉花

• Original article • Previous Articles     Next Articles

The Response of Sea-island Cotton Strains to the Spraying Time and Frequency of Defoliants

BAI Yulin(), WANG Chengqiang, DU Bin, LIU Lu, LIU Xia()   

  1. Changji Esquel Textile Co., Ltd., Changji, Xinjiang 831100
  • Received:2022-04-15 Revised:2022-08-15 Online:2023-02-25 Published:2023-02-22

Abstract:

In order to clarify the effects of spraying time and frequency of defoliants on leaf abscission, boll opening, yield traits and fiber quality of different sea-island cotton strains, ZX102 and ZX113 were used as test materials and 3 spraying times and 2 spraying frequencies were set. Three-factor completely randomized experiments were used to analyze the responses of different sea-island cotton strains to different treatments. The result showed that the use of defoliants significantly improved the defoliation rate, and the defoliation rate of the two strains at 40% and 50% boll opening rate reached 90% about 15 days after using defoliants, and they were significantly higher than that of the water control (P<0.05). The use of defoliants at 40% and 50% boll opening rate reduced the macron value, fibre length and fibre strength of the two strains, which were manifested as CK>T2>T1; at 40% boll opening rate, the macron value under T1 treatment was significantly lower than that under CK (P<0.05). The boll weight and seed value of the two strains under different treatments were CK>T2>T1, and the boll weight at 40% boll opening rate under T1 treatment was significantly lower than that under CK (P<0.05). In order to ensure the yield and fiber quality, T2 spraying can be used at 50% boll opening rate for mechanical harvesting of sea-island cotton.

Key words: sea-island cotton, defoliant, spraying time, spraying frequency, fiber quality, yield