Frigero Maria Luisa P, Boaro Carmen S F, Galetto Leonardo, Tunes Priscila, Guimarães Elza
Postgraduate Program in Plant Biology, Institute of Biosciences, São Paulo State University, Botucatu, Brazil.
Laboratory of Plant Growth, Department of Biodiversity and Biostatistics, Institute of Biosciences, São Paulo State University, Botucatu, Brazil.
Sci Rep. 2025 Mar 29;15(1):10852. doi: 10.1038/s41598-025-94565-2.
Both severe reductions and increases in rainfall can stress plants and modify floral traits involved in plant-pollinator interactions, such as nectar production. Animal pollination is responsible for most plant species' reproduction including several crops that rely especially on bees for fruit and seed production. Thus, extreme climate events can cause disruptions in pollination mutualism and lead to a decrease in the production of many crops worldwide. This study investigated the effects of changes in rainfall on nectar availability to pollinators at flower-, plant- and agricultural-scale, using an outcrossing bee-pollinated model crop. We experimentally simulated four scenarios: Control, Heavy rainfall, Rainfall reduction and Drought. All treatments but Rainfall reduction affected nectar traits at flower-scale. At plant- and agricultural-scale, Heavy rainfall increased nectar caloric offer (+ 79% and + 74%, respectively), while Rainfall reduction and Drought decreased it (- 37% and - 34%; - 98% and - 95%, respectively). Thus, drought treatments resulted in less resources available to pollinators The predicted rainfall shifts mediated by climate change may negatively affect cross-pollinated crops worldwide, as changes in nectar traits are prone to affect pollinator foraging behaviour and energy intake rate, decreasing pollination and fruit production. In summary, food security for humans may be closely linked to food security for pollinators.
降雨量的大幅减少和增加都会给植物带来压力，并改变植物与传粉者相互作用中涉及的花部特征，比如花蜜分泌量。动物传粉对大多数植物物种的繁殖至关重要，包括几种特别依赖蜜蜂进行果实和种子生产的作物。因此，极端气候事件会导致传粉互利共生关系受到干扰，并致使全球许多作物产量下降。本研究使用一种异交蜜蜂传粉的模式作物，在花朵、植株和农业尺度上调查了降雨变化对传粉者可获得花蜜量的影响。我们通过实验模拟了四种情景：对照、强降雨、降雨减少和干旱。除降雨减少外，所有处理都影响了花朵尺度上的花蜜特征。在植株和农业尺度上，强降雨增加了花蜜的热量供应（分别增加了79%和74%），而降雨减少和干旱则降低了花蜜热量供应（分别减少了37%和34%；98%和95%）。因此，干旱处理导致传粉者可获得的资源减少。气候变化介导的预计降雨变化可能会对全球异花授粉作物产生负面影响，因为花蜜特征的变化容易影响传粉者的觅食行为和能量摄入率，从而降低授粉和果实产量。总之，人类的粮食安全可能与传粉者的粮食安全密切相关。
