Department of Agricultural, Forest and Food Sciences, Plant Genetics and Breeding, University of Torino, Grugliasco, Italy.
J Sci Food Agric. 2021 Aug 30;101(11):4724-4734. doi: 10.1002/jsfa.11118. Epub 2021 Feb 11.
Crops are exposed to recurrent and acute drought stress episodes during their vegetative and reproductive cycles, and these episodes are increasingly frequent due to ongoing climate change. Sweet pepper (Capsicum annuum), alias bell pepper, is one of the most widely cultivated vegetables and is grown in open fields worldwide. Here we assessed the effect of acute water stress, applied to a breeding line of sweet pepper at three stages of plant development: five true-leaves (Stage 1), production of the third flower (Stage 2) and setting of the first fruit (Stage 3), on the production and biochemical composition of its ripe fruits.
The water stress at Stages 1 and 2 induced a delay in fruit ripening, while at Stage 3 caused a drop in production. The biochemical composition of ripe fruits was assessed by quantifying their content in vitamin C, sugars, organic acids, flavonoids as well as 190 volatile organic compounds, mainly belonging to the chemical classes of hydrocarbons, alcohols, ketones, esters, terpenes, aldehydes and ethers. Our results highlight that, at different stages of plant development, acute water stresses modulate differently the accumulation of bioactive compounds in fruits, which play a key role in setting the redox-status and osmotic adjustment of the plant. This was also the case for volatile compounds since, within each chemical class, different compounds varied their content in ripe fruits.
On the whole, our results demonstrate that water stresses potentially affect the organoleptic and sensory qualities of bell pepper fruits depending on when they occur. © 2021 Society of Chemical Industry.
作物在其营养生长和生殖生长周期中会反复受到急性干旱胁迫，并且由于持续的气候变化，这些胁迫越来越频繁。甜椒（Capsicum annuum），别名彩椒，是种植最广泛的蔬菜之一，在世界各地的露天田地中种植。在这里，我们评估了急性水分胁迫对甜椒选育系在三个发育阶段（五片真叶期（阶段 1）、第三朵花生产期（阶段 2）和第一果座果期（阶段 3））的影响，该胁迫对其成熟果实的产量和生化成分的影响。
在阶段 1 和 2 施加水分胁迫会导致果实成熟延迟，而在阶段 3 则会导致产量下降。通过定量测定成熟果实中维生素 C、糖、有机酸、类黄酮以及 190 种挥发性有机化合物的含量来评估其生化成分，这些化合物主要属于碳氢化合物、醇、酮、酯、萜烯、醛和醚等化学类别。我们的结果表明，在植物发育的不同阶段，急性水分胁迫以不同的方式调节果实中生物活性化合物的积累，这些化合物在设定植物的氧化还原状态和渗透调节中起着关键作用。挥发性化合物也是如此，因为在每个化学类别中，不同的化合物在成熟果实中的含量都有所不同。
总的来说，我们的研究结果表明，水分胁迫可能会根据发生的时间影响甜椒果实的感官和感官品质。© 2021 化学工业学会。
