A common modern cultivation practice is bagging the fruit bunch if date palm (Phoenix dactylifera L.) which may influence fruit maturity and nutraceutical quality. Exposure of fruits to photooxidative stress induces changes in the endogenous concentrations of plant hormones and other metabolites, which may cause accelerated fruit maturity. This study was conducted to examine the effect of exposure to direct and indirect sunlight on date palm fruit development. The indirect sunlight treatment was simulated by fruit bunch bagging, a common practice in modern date production. The exposure of date palm fruits to direct sunlight-induced photooxidative stress causing an increased concentration of ascorbic acid and decreased content of chlorophyll, anthocyanins, carotenoids, and phenols compared to the fruit bagging treatment. Direct sunlight also reduced the concentration of phytohormones, including indoleacetic acid, gibberellin, and zeatin, but increased abscisic acid accumulation. The directly-exposed fruits reached a partially-mature stage (Rutab) in August, whereas the bagged fruits remained at the immature stage (Khalal). This study is the first to describe the biochemical basis of the observed improvement of date palm fruit development in response to reduced light intensity. Besides, it provides insights into controlling date palm fruit maturity and subsequently prolonging the shelf life dates on the tree; thus, extending the marketing period for the benefit of the farmers.

中文翻译：

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内源性植物激素的光氧化应激调节和抗氧化物质在枣椰树 (Phoenix dactylifera L.) 中的积累和果实成熟度

一种常见的现代栽培做法是将枣椰树 (Phoenix dactylifera L.) 的果串装袋，这可能会影响果实成熟度和营养品质量。果实暴露于光氧化胁迫会导致植物激素和其他代谢物的内源浓度发生变化，这可能会导致果实加速成熟。本研究旨在检验直接和间接阳光照射对椰枣果实发育的影响。通过果串套袋模拟间接日光处理，这是现代枣生产中的常见做法。与水果套袋处理相比，枣椰果实暴露于阳光直射引起的光氧化应激下，导致抗坏血酸浓度增加，叶绿素、花青素、类胡萝卜素和酚类含量降低。阳光直射也会降低植物激素的浓度，包括吲哚乙酸、赤霉素和玉米素，但会增加脱落酸的积累。直接暴露的水果在 8 月达到部分成熟阶段 (Rutab)，而袋装水果仍处于未成熟阶段 (Khalal)。这项研究首次描述了观察到的椰枣果实发育因光照强度降低而改善的生化基础。此外，它还提供了控制椰枣果实成熟度并随后延长树上保质期的见解；从而延长销售期，造福农民。直接暴露的水果在 8 月达到部分成熟阶段 (Rutab)，而袋装水果仍处于未成熟阶段 (Khalal)。这项研究首次描述了观察到的椰枣果实发育因光照强度降低而改善的生化基础。此外，它还提供了控制椰枣果实成熟度并随后延长树上保质期的见解；从而延长销售期，造福农民。直接暴露的水果在 8 月达到部分成熟阶段 (Rutab)，而袋装水果仍处于未成熟阶段 (Khalal)。这项研究首次描述了观察到的椰枣果实发育因光照强度降低而改善的生化基础。此外，它还提供了控制椰枣果实成熟度并随后延长树上保质期的见解；从而延长销售期，造福农民。它提供了控制椰枣果实成熟度和随后延长树上保质期的见解；从而延长销售期，造福农民。它提供了控制椰枣果实成熟度和随后延长树上保质期的见解；从而延长销售期，造福农民。