Delaying initial irrigation is feasible because the upper canopy has significant advantages in the distribution of photosynthetic products in cotton bolls

文献类型： 外文期刊

第一作者： Li, Nannan

作者： Li, Nannan;Shi, Xiaojuan;Shi, Feng;Zhang, Humei;Tian, Yu;Wang, Jun;Li, Yuxiang;Luo, Honghai;Tian, Liwen;Hao, Xianzhe;Wang, Jun

作者机构：

关键词： Cotton yield; Canopy photosynthesis; Irrigation strategy; Deep drip irrigation

期刊名称：INDUSTRIAL CROPS AND PRODUCTS （ 影响因子：6.2； 五年影响因子：6.2 ）

ISSN： 0926-6690

年卷期： 2025 年 229 卷

页码：

收录情况： SCI

摘要： The production of cotton and other crops must be efficient and sustainable at a global scale. Deep drip irrigation and dense planting with equal row spacing are innovative cotton planting strategies designed to address persistent high production costs. We hypothesize that adjusting the irrigation amount and frequency in this approach will strongly benefit yield, particularly at the population level. Therefore, a field experiment spanning three years (2021-2023) was conducted; the split-plot design featured two different irrigation amounts (m(3) ha(-1); I1: 3177; I2: 3840) for the main plots and 9 (F1), 8 (F2), and 7 (F3) irrigation frequencies for the subplots. The irrigation frequency was varied by adjusting the timing of the initial and final irrigation events. The I2 treatment increased the leaf area index (LAI) in the upper plant parts and the chlorophyll (Chl) content to varying degrees. These physiological changes increased the canopy apparent photosynthesis (CAP) by 18.8-29.5 % and canopy respiration (CR) by 17.6-78.6 %. Additionally, the ratio of upper CR to total CAP (CR/TCP) increased by 26.2-34.4 % from 105 to 120 days after emergence (DAE). Concurrently, the I2 treatment substantially increased the 13C content (13Ci) in cotton roots, stems, leaves, and bolls in particular, 13C allocation rate to bolls increased by 4.8-5.5 % from 90-120 DAE ultimately leading to increases in boll number, boll weight, and yield. In the I2 treatment group, the F2 treatment specifically amplified these effects during the late growth period. The I2F2 treatment led to increases in the upper canopy LAI and Chl content, consequently increasing the upper CAP and CR/TCP. This further promoted significant increases in the (13)Ci and C-13 distributions to bolls, resulting in a substantial increase in boll biomass of 19.1-33.2 %. This ultimately resulted in a greater boll number (3.0-13.0 % increase) and seed yield (3.9-20.5 % increase). However, in the I1 treatment group, the F1 treatment resulted in greater distribution of Chl a+b, CAP, CR, CR/TCP, (13)Ci and C-13 to bolls, with increases of 2.1-11.5 %, 8.5-32.1 %, 4.3-22.7 %, 2.1-7.8 %, 33.6-63.0 %, and 3.3-6.3 %, respectively. Consequently, boll biomass increased by 7.8-11.1 %, resulting in 6.4 % and 7.7 % increases in seed and lint yields, respectively. Moreover, correlation analysis revealed that higher levels of cotton LAI, Chl content, CAP, CR, biomass, and (13)Ci in leaves and bolls, along with a higher allocation rate of C-13 to bolls, collectively contributed to greater yields. Under sufficient irrigation conditions (3840 m(3) ha(-1)), delaying the first irrigation (F2) can result in the optimal yield; however, at a reduced irrigation amount (3177 m(3) ha(-1)), the lint yield under conventional-frequency irrigation (F1) is still much higher than the average yield in the local region. This study offers recommendations for suitable irrigation frequencies under deep drip irrigation and variable moisture regimes, enhancing the environmental friendliness and effective resource utilization of the cotton production.

分类号：

  • 相关文献
作者其他论文 更多>>

微信小程序