Delamare Jérémy, Personeni Emmanuelle, Le Guédard Marina, Kim Tae Hwan, Elie Nicolas, Bressan Mélanie, Cantat Olivier, Dupas Quentin, Trinsoutrot-Gattin Isabelle, Prigent-Combaret Claire, Brunel-Muguet Sophie
Normandie Université, UNICAEN, INRAE, UMR 950 Ecophysiologie Végétale, Agronomie Et Nutritions N, C, S, Esplanade de La Paix CS14032, 14032, Caen Cedex 5, France.
Univ. Bordeaux, CNRS, UMR 5200 Laboratoire de Biogenèse Membranaire (LBM), 71, Avenue Edouard Bourlaux, 33883 Cedex, Villenave d'Ornon, France.
Planta. 2025 Jan 6;261(2):26. doi: 10.1007/s00425-024-04600-1.
The effects of intense heat during the reproductive phase of two Brassica species-B. napus and C. sativa-could be alleviated by a prior gradual increase exposure and/or PGPR inoculation. Abct. Among extreme weather events caused by climate change, heat waves are one of the most threatening issues for food security. Heat stress is known to be particularly penalizing at the reproductive stage for oleaginous crops, such as oilseed rape and camelina, and is responsible for crop failures as a consequence of yield losses and lower quality of harvest plants parts. In this context, our study aims to analyze two acclimation strategies that rely on the induction of signals prior to an intense heat stress event, i.e., thermopriming (herein, a gradual increase in temperature) and bacteria inoculations (herein, two Plant Growth-Promoting Rhizobacteria (PGPR) were tested). In the two experiments, we assessed the expected beneficial effects of these two acclimation strategies on yield components, seed quality criteria (nutritional and related to dormancy). While thermopriming improved heat stress tolerance in B. napus cv Aviso by maintaining yield, seed nutritional quality and seed dormancy, the effects of the gradual increase prior to the heat stress were even more negative than the later intense heat stress event in C. sativa cv Calena which resulted in cumulated negative effects. The experimentation based on PGPR inoculation highlighted similar trends to thermopriming in B. napus cv Aviso but to a lesser extent. However, in C. sativa cv Calena, very weak effects of PGPR inoculation upon heat stress were observed. Finally, these two acclimation strategies were shown to help alleviate the impacts of intense heat stress but in a species-dependent manner. This study should be deepened by exploring the behaviors of more cultivars of oilseed rape and camelina in the perspective to generalize these results at the species scale.
在甘蓝型油菜和亚麻荠这两种芸苔属植物的生殖阶段，通过事先逐渐增加暴露温度和/或接种植物根际促生细菌（PGPR），可减轻高温的影响。在由气候变化引起的极端天气事件中，热浪是对粮食安全最具威胁的问题之一。众所周知，热胁迫对油菜和亚麻荠等油料作物的生殖阶段特别不利，会导致作物因产量损失和收获植株部分质量下降而歉收。在此背景下，我们的研究旨在分析两种驯化策略，这两种策略依赖于在强烈热胁迫事件之前诱导信号，即热预适应（在此，温度逐渐升高）和细菌接种（在此，测试了两种植物根际促生细菌（PGPR））。在这两个实验中，我们评估了这两种驯化策略对产量构成要素、种子质量标准（营养和与休眠相关的）的预期有益影响。虽然热预适应通过维持产量、种子营养质量和种子休眠提高了甘蓝型油菜品种Aviso的耐热性，但在亚麻荠品种Calena中，热胁迫前温度逐渐升高的影响甚至比后来的强烈热胁迫事件更负面，导致了累积的负面影响。基于PGPR接种的实验在甘蓝型油菜品种Aviso中突出了与热预适应相似的趋势，但程度较小。然而，在亚麻荠品种Calena中，观察到PGPR接种对热胁迫的影响非常微弱。最后，这两种驯化策略被证明有助于减轻强烈热胁迫的影响，但具有物种依赖性。应通过探索更多油菜和亚麻荠品种的行为来深化这项研究，以便在物种尺度上推广这些结果。
