Sun Yanli, Sun Sijie, Zahid Muhammad Salman, Qiu Qian, Wang Lei, Wang Shiping
Department of Plant Science, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China.
Microbial Ecology and Truffle Innovation, Mycorrhizal Systems Ltd., Lancashire, United Kingdom.
Front Plant Sci. 2025 Apr 3;16:1563270. doi: 10.3389/fpls.2025.1563270. eCollection 2025.
The increasingly severe global greenhouse effect has become an irreversible trend, significantly impacting viticulture regions through heat stress during various grape growth stages, especially under protected cultivation conditions where high temperatures frequently occur. Therefore, studying the impact of heat stress on grapevine growth and fruit quality across the entire growth and development period, along with effective mitigation measures, is crucial.
In this study, three-year-old 'Kyoho' grapevines were used as experimental materials, with four treatment groups: a control group, a hightemperature group (heat stress, HT), a high-temperature + brassinolide group (BR), and a high-temperature + salicylic acid group (SA). During the flowering, young berry swelling, and veraison stages, BR and SA were applied via nutrient solutions every seven days.
The results demonstrated that BR restored the maximum photosynthetic rate (Amax) to 96.14% of CK by the 18th day of flowering, significantly outperforming SA's recovery rate of 86.64%. Both treatments maintained light saturation points (1200 μmol•m•s) and CO2 saturation thresholds equivalent to CK. The decline in PSII photochemical efficiency (Fv/Fm) was reduced from 18% in HT to 5-8% in BR/SA-treated groups, with BR showing minimal deviation (2.3%) from CK during veraison, effectively mitigating PSII photoinhibition caused by heat stress. Furthermore, both treatments reduced leaf malondialdehyde (MDA) content, minimizing membrane lipid peroxidation, while increasing soluble protein (SP) content to protect leaves. Under heat stress, BR notably improved the fruit set rate by 22.67% compared to HT (SA: 13%), promoted berry expansion, and enhanced the accumulation of sugars and anthocyanins in the fruit skin, with SA showing similar, though slightly less pronounced, effects.
These findings provide valuable theoretical insights into the use of exogenous hormones in root nutrient solutions as a strategy to mitigate the adverse effects of heat stress in grape production.
日益严峻的全球温室效应已成为不可逆转的趋势，在葡萄生长的各个阶段通过热胁迫对葡萄种植区产生重大影响，特别是在高温频繁出现的设施栽培条件下。因此，研究热胁迫对葡萄整个生长发育期生长和果实品质的影响以及有效的缓解措施至关重要。
本研究以三年生‘巨峰’葡萄树为试验材料，设置四个处理组：对照组、高温组（热胁迫，HT）、高温+油菜素内酯组（BR）和高温+水杨酸组（SA）。在开花期、幼果膨大期和转色期，每隔七天通过营养液施用BR和SA。
结果表明，到开花第18天，BR将最大光合速率（Amax）恢复到对照（CK）的96.14%，显著优于SA的86.64%的恢复率。两种处理均保持了与CK相当的光饱和点（1200μmol•m•s）和二氧化碳饱和阈值。PSII光化学效率（Fv/Fm）的下降从HT组的18%降低到BR/SA处理组的5 - 8%，在转色期BR与CK的偏差最小（2.3%），有效减轻了热胁迫引起的PSII光抑制。此外，两种处理均降低了叶片丙二醛（MDA）含量，使膜脂过氧化最小化，同时增加了可溶性蛋白（SP）含量以保护叶片。在热胁迫下，与HT相比，BR显著提高了坐果率22.67%（SA为13%），促进了浆果膨大，并增强了果实表皮中糖分和花青素的积累，SA表现出类似但稍弱的效果。
这些发现为在根系营养液中使用外源激素作为减轻葡萄生产中热胁迫不利影响的策略提供了有价值的理论见解。
