Piriformospora indica promotes some morphophysiological traits, yield and ion homeostasis of barley (Hordeum Vulgare L.) under drought stress

Drought is one of the major constraints to crop plant growth and development. The endophytic fungus, Piriformospora indica increases plant growth and development and enhances abiotic stress tolerance. To better understand the effect of P. indica inoculation on some morphophysiological traits and yield of Barley (Hordeum Vulgare L.) under drought stress condition, we designed a factorial experiment in a completely randomized design with three replications. The experimental factors included two fungal levels (inoculated and non-inoculated) and three drought levels (F.C., 50% F.C., 25% F.C.). The results showed that inoculation of barley plants with P. indica enhances dry weight of colonized plants under both well-watered (7%) and water-deficit conditions (43%). Based on experiment data, P. indica increased carbon (4%), potassium (20%), proline (2.03 times) and GABA (20%) content in inoculated plants compared with control plant under drought stress; Besides, endophyte fungus P. indica promoted the photosynthetic capacity of inoculated plants by increasing K/Na and C/N ratios, hence improve drought stress tolerance. The results also showed that P. indica increases the most of the measured yield parameters like as seed (86%) and spike number (66%), TGW (26%) and seed yield (1.9 times) in inoculated plants compared with control plants under ambient and stress condition. As, P. indica can be easily propagated in the absence of a host plant, it can be concluded that treatment with this endophytic fungus as bio-fertilizer can enhance the growth and yield of barley plants, which may act as an alternative to conventional chemical-based strategies.