JCR-Effects of mepiquat chloride on yield and main properties of cottonseed under different plant densities

缩节胺对不同密度群体棉籽产量和主要品质指标的影响

赵文青^1,2，闫强¹，杨晓妮¹，王乐然¹，陈兵林^1,2，孟亚利^1,2*，周治国^1,2

(1. 农业部作物生理生态与生产管理重点实验室, 南京 210095；2. 江苏省现代作物生产协同创新中心 (JCIC-MCP), 南京农业大学, 南京 210095)

摘要：

[背景] 棉籽油分、蛋白质含量和萌发特性是主要的棉籽品质指标。种植密度和缩节胺如何影响上述品质指标尚不明确。本研究于2013-2014年在江苏省大丰设置了种植密度（1.35万，2.55万，3.75万，4.95万株·hm^-2）和缩节胺（0，135 g·hm^-2）试验，以探索种植密度和缩节胺对棉籽产量和品质的影响。

[结果] 不同种植密度群体喷施缩节胺均显著降低棉花株高和果枝长度，减少果枝数，形成较为紧凑的株型结构。棉籽产量随种植密度的增加呈先升高后降低的趋势，无论喷施缩节胺与否，均在3.75万株·hm^-2达到最大。籽指、棉籽油分含量和活力指数随种植密度增加显著下降，各种植密度条件下喷施缩节胺均可显著提高上述指标。种植密度与缩节胺对棉籽产量及品质指标的影响均未存在互作效应。相关分析显示籽指和棉籽油分含量与活力指数呈显著的正相关关系，可以作为判断棉籽活力高低的品质指标。

[结论] 在长江下游地区，春棉种植选择密度3.75万株·hm^-2与喷施135 g·hm^-2缩节胺相结合，可实现棉籽产量及主要品质的双重提高。

关键词：缩节胺；种植密度；棉籽产量；油分含量；种子萌发特性

[Background] Cottonseed oil and protein content as well as germination traits are major indicators of seed quality. However, the responses of these indicators to plant density and mepiquat chloride (MC) are still uncertain. To investigate plant density and MC effects on cottonseed yield and main quality parameters, we conducted a two-year field experiment including four plant densities (1.35, 2.55, 3.75 and 4.95 plants·m^??2) and two doses of MC (0 and 135?g·hm^??2) in Dafeng, Jiangsu Province, in 2013 and 2014.

[Results] The application of MC reduced plant height, fruit branch length and fruiting branch number under different plant densities, resulting in a lower and more compact plant canopy. Cottonseed yield showed a nonlinear increase as plant density increasing and achieved the highest value at 3.75 plants·m^??2, regardless of MC application. No significant interactions were found between plant density and MC for cottonseed yield and quality parameters. The 100-seed weight, cottonseed oil content and vigor index significantly decreased as plant density increased, while these parameters significantly increased with MC applying under different plant densities. Seed vigor index was positively correlated with 100-seed weight and seed oil content across different plant densities and MC treatments.

[Conclusions] Thus, application of MC could realize a win-win situation between cottonseed yield and main quality parameters under various densities; and plant density of 3.75 plants·m^??2 combined with 135?g·hm^??2 of MC applying is optimal for high cottonseed yield and quality in this cotton production area.

[Title] Effects of mepiquat chloride on yield and main properties of cottonseed under different plant densities

[Authors] ZHAO Wenqing, YAN Qiang, YANG Hongkun, YANG Xiaoni, WANG Leran, CHEN Binglin, MENG Yali and ZHOU Zhiguo

Journal of Cotton Research. 2019; 2:10

https://doi.org/10.1186/s42397-019-0026-1

https://jcottonres.biomedcentral.com/articles/10.1186/s42397-019-0026-1