Physiological and biochemical adaptation of arbuscular mycorhizal fungi (AMF) inoculated Citrus jambhiri (Jatti khatti) seedlings under water deficit stress conditions

The effect of Arbuscular mycorrhizal fungi (AMF) on physiological and biochemical parameters of plants under well watered (WW) and water deficit stress (WDS) conditions were studied under glasshouse conditions at the Division of Fruits and Horticultural Technology and National Phytotron Facility, IARI, New Delhi. Citrus jambhiri seedlings (Jatti khatti) were inoculated with two strains of AMF, viz., Glomus fasciculatum (S-1) and Glomus intraradices (S-2) along with non-mychorrhizal (NM) control. The plants were allowed to grow normally upto 120 days after inoculation with proper irrigation, thereafter, the plants were subjected to WW and WDS treatments for twenty five days. Upon exposure to the treatments, G. fasciculatum inoculated plants showed maximum root colonization in Jatti khatti seedlings under both WW (49.38 %) and WDS (49.10 %) conditions. No colonization was reported in NM plants. AMF treated plant types (S-1 and S-2) showed improved physiological and biochemical changes viz. photosynthetic rate, stomatal conductance, relative water content, proline, total phenol, chlorophyll a, chlorophyll b and total carotenoids contents respectively compared to NM plants under WDS conditions. AMF inoculated plants also had increased uptake of P, K, Ca, Mg and Cu relative to NM plants. Our findings clearly revealed that AMF colonization during WDS improved the growth, physiological, biochemical parameters and had a positive effect on adaptation and water stress mitigation of Jatti khatti seedlings.