Instituto de Ciencias Biológicas, Universidad de Talca, Campus Talca, Chile.
Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Universidad Católica del Norte, Coquimbo, Chile.
Sci Rep. 2020 Apr 2;10(1):5819. doi: 10.1038/s41598-020-62544-4.
Climatic change is pointed as one of the major challenges for global food security. Based on current models of climate change, reduction in precipitations and in turn, increase in the soil salinity will be a sharp constraint for crops productivity worldwide. In this context, root fungi appear as a new strategy to improve plant ecophysiological performance and crop yield under abiotic stress. In this study, we evaluated the impact of the two fungal endophytes Penicillium brevicompactum and P. chrysogenum isolated from Antarctic plants on nutrients and Na contents, net photosynthesis, water use efficiency, yield and survival in tomato and lettuce, facing salinity stress conditions. Inoculation of plant roots with fungal endophytes resulted in greater fresh and dry biomass production, and an enhanced survival rate under salt conditions. Inoculation of plants with the fungal endophytes was related with a higher up/down-regulation of ion homeostasis by enhanced expression of the NHX1 gene. The two endophytes diminished the effects of salt stress in tomato and lettuce, provoked a higher efficiency in photosynthetic energy production and an improved sequestration of Na in vacuoles is suggested by the upregulating of the expression of vacuolar NHX1 Na/H antiporters. Promoting plant-beneficial interactions with root symbionts appears to be an environmentally friendly strategy to mitigate the impact of climate change variables on crop production.
气候变化被认为是全球粮食安全的主要挑战之一。基于当前的气候变化模型，降水减少，进而土壤盐度增加，将成为全球作物生产力的严重制约因素。在这种情况下，根真菌作为一种提高植物生理生态性能和作物在非生物胁迫下产量的新策略出现了。在这项研究中，我们评估了从南极植物中分离出的两种内生真菌 Penicillium brevicompactum 和 P. chrysogenum 对养分和 Na 含量、净光合作用、水分利用效率、产量和番茄和生菜盐胁迫条件下的存活率的影响。内生真菌对植物根系的接种导致在盐胁迫条件下产生更大的鲜重和干重生物量，以及更高的存活率。内生真菌的接种与 NHX1 基因的增强表达有关，这与离子稳态的更高的上调/下调有关。这两种内生真菌减轻了番茄和生菜的盐胁迫效应，通过上调液泡 NHX1 Na/H 反向转运蛋白的表达，推测其提高了光合能量产生的效率，并改善了 Na 在液泡中的隔离。促进与根共生体的植物有益相互作用似乎是一种减轻气候变化变量对作物生产影响的环保策略。
