Root endophytes improve physiological performance and yield in crops under salt stress by up-regulating the foliar sodium concentration

Abstract

Increase in the soil salinity will be a conspicuous constraint for both native plant communities as well as several crops worldwide. In this context plant root-associated fungi appear as a new strategy to improve ecophysiological performance and yield of crops under abiotic stress. Here, we evaluated how the inoculation of fungal endophytes isolated from Antarctic plants can improve the ecophysiological performance in cultivars of tomato and lettuce, grown under different salt conditions. In addition, we assessed if the expression of the NHX1 gene that is related with salt tolerance is enhanced in presence of fungal endophytes. Finally, we evaluated the regulation the nutritional status and specifically the Na+ content in leaves. Overall, those individuals with presence of endophytes showed higher ecophysiological performance. In addition, the presence of fungal endophytes was correlated with a higher regulation of ion homeostasis by enhanced expression of NHX1 gene. Our results suggest that presence of fungal endophytes could minimize the negative effect of salt by improving osmotic tolerance through ecophysiological and molecular mechanisms. Thus, root-endophytes might be a successful biotechnological tool to maintain high levels of ecophysiological performance and productivity in zones under osmotic stress, acting as potential solution to maintain the global food security.\n\nHighlightWe showed that functional symbiosis improve the physiological performance and yield in crops subjected to salinity, by biochemical and molecular mechanisms. Thus, here we pointed a successful strategy to meet the future challenges for help to maintain the food security.