Arbuscular Mycorrhizal Increases the Concentration of Potassium and KUPs Activity in Phaseolus vulgaris Under Drought Stress and ABA Application

Arbuscular mycorrhizal fungi (AMF) symbiotically with the roots of most plants play a prominent role in increasing plant growth and yield. However, the mechanistic understanding of how AMF and the phytohormone abscisic acid (ABA) jointly regulate potassium (K⁺) uptake and the expression of K⁺ transporter (KUP) genes in common bean under drought stress remains unclear. In the current study, the effect of symbiotic of Phaseolus vulgaris with Funneliformis mosseae and Rhizophagus irregularis under drought stress and ABA application on the concentration of potassium, phosphorus, and photosynthetic pigment content, soluble sugar content, and KUP transporters expression was investigated. The results revealed that potassium and phosphorus concentrations in root and shoot tissues increased under symbiotic conditions with AMFs. Under normal plant water conditions, symbiotic interaction with F. mosseae increased the potassium content in the shoot by 1.55‐fold, and symbiotic interaction with R. irregularis increased the potassium content by 1.64‐fold. Also, under drought stress, symbiotic interaction with AMFs was able to increase potassium and phosphorus uptake compared to non‐symbiosis. Besides, the photosynthetic pigment content increased in response to symbiotic interaction with AMFs. ABA did not show significant effects on potassium and phosphorus absorption. The expression pattern of PvKUPs revealed that most of these genes are induced in response to symbiosis with AMFs and drought stress. PvKUP3 and PvKUP5 genes were induced more under symbiosis with R. irregularis, and PvKUP11 and PvKUP18 more under symbiosis with F. mosseae . The results of this study provided a preliminary insight into the simultaneous interaction of symbiosis with AMFs and drought stress and the application of ABA on potassium uptake and transport, which will be useful in future studies related to plant‐microbe interactions.