Abstract Growth and reproductive structure development in cotton (Gossypium hirsutum) is dependent on light intensity, which is often irregular in tropical environments due to shading from cloudiness associated with the monsoon. The objective of this study was to evaluate the effects of cloudiness on reproductive organ abscission and how subsequent compensatory organ replacement, with the provision of irrigation, might recover yield in the semi-arid monsoon tropics. Cotton cultivars representing different morphology were sown in field experiments at closely timed intervals during the early monsoon over five seasons to expose crops to varying amounts of cloud-related shading, creating a matrix of crop responses. A wide range for lint yield (1099 to 2900 kg ha−1) was symptomatic of the treatments’ exposure to highly varied environmental conditions. Lint yield was moderately correlated (P The clustering of sowing times into groups according to similarities in the number and final distribution of bolls within the crop canopy provided a mechanism to identify sowing time treatments that shared similar compensation responses. The highest group yields occurred when minimal cloudiness during flowering allowed uninterrupted boll accumulation or alternatively when moderate boll losses from the lower canopy were compensated via additional later set bolls when radiation improved. Yield recovery was restricted for groups where cloudiness was ongoing or increased during late flowering or when canopy factors detracted from efficient use of available radiation. Extrapolation of the linear relationship between boll number and incident radiation showed boll retention was maximised at a mean daily value of 24.2 MJ m−2 (Rmax). Quantification of Rmax was a key finding as it could be applied to calculate a cumulative radiation deficit (RD) = ∑ (if daily radiation is Yield compensation from cloud induced fruit abscission in the semi-arid tropics will be assisted by management that can extend flowering to create new fruiting sites whilst balancing the partitioning of canopy growth.

中文翻译：

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热带季风季节的棉花生产。I – 可变辐射对棉铃损失、补偿和产量的影响

摘要 棉花 (Gossypium hirsutum) 的生长和生殖结构发育依赖于光照强度，由于与季风相关的阴天阴影，光照强度在热带环境中通常是不规则的。本研究的目的是评估阴天对生殖器官脱落的影响，以及随后的补偿性器官置换，通过提供灌溉，如何在半干旱季风热带地区恢复产量。在五个季节的早期季风期间，在田间试验中以紧密的时间间隔播种代表不同形态的棉花品种，使作物暴露于不同数量的与云相关的阴影中，从而形成作物反应矩阵。皮棉产量的广泛范围（1099 至 2900 kg ha-1）是处理暴露于高度变化的环境条件的症状。棉铃数和入射辐射之间的线性关系的外推表明棉铃滞留量在 24.2 MJ m-2 (Rmax) 的平均日值时最大化。Rmax 的量化是一个关键发现，因为它可以用于计算累积辐射赤字 (RD) = ∑（如果每日辐射是半干旱热带地区云引起的果实脱落的产量补偿，将通过可以延长开花的管理来辅助创建新的结果点，同时平衡树冠生长的分区。