Mitigation of Drought Stress in Wheat by Bio-priming by PGPB Containing ACC Deaminase Activity

Abstract

Out of stress management strategies used for drought, inoculation of plant growth-promoting bacteria holds a major position due to sustainable, low-cost, and versatile properties. The plant growth-promoting bacteria, particularly containing 1-aminocyclopropane-1-carboxylic acid deaminase activity, have a critical location since they restrict ethylene synthesis under stress conditions thereby improving stress tolerance index. In this experiment, seeds of two wheat cultivars were primed with three bacterial strains and seedlings were grown under stress and nonstress conditions. The study was laid out in completely randomized factorial design with three replications. While plant growth achieved top performance with synthetic fertilizer in 80% of field capacity, increasing drought stress restricted the efficiency of synthetic fertilizer. In contrast, plant growth-promoting bacteria-priming promoted plant growth and dry matter accumulation under optimum and drought conditions. Increase of dry matter accumulation in treatments as control plants varied between 17.1% and 57.1% under 80% of field capacity while it changed between 0.2% and 35.1% under drought conditions. TV126C and TV24C induced stress tolerance index in sensitive and tolerant cultivars under drought and optimum conditions. In conclusion, it is considered that bio-priming with plant growth-promoting bacteria involving 1-aminocyclopropane1-carboxylic acid deaminase enzyme activity might be an effective and sustainable management strategy to drought stress in wheat cultivation.