Influence of IAA and ACC Deaminase Producing Fluorescent Pseudomonads in Alleviating Drought Stress in Wheat (Triticum aestivum)

Drought is one of the major constraints limiting agricultural production worldwide. Soil bacteria containing 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase and indole acetic acid (IAA) producing traits with the potential for the alleviation of drought stress in combination with plant growth promotion would be extremely useful tools in sustainable farming. The present study was undertaken with two drought-tolerant bacteria Pseudomonas fluorescens strain DPB15 and P. palleroniana strain DPB16 containing ACC deaminase activity as isolated from rainfed agriculture areas of Kumaun regions of Uttarakhand, India. There were two sets of pot trails, i.e., non-stressed (watered) and drought stressed (non-watered). The growth parameters were recorded after fifty-four days of growth. Bacterial inoculation enhanced the growth of wheat in terms of root and shoot biomass, height and foliar nutrient content in treated as compared to untreated plants. In addition, a significant increase in antioxidant activity (SOD, CAT, GPX and APX) was also observed where bacterial treatment improves the plant fitness by protecting it from the oxidative damage created by drought. A correlation study between non-enzymatic and enzymatic antioxidants demonstrated that a perfect positive significant correlation between SOD and Chl, GPX and Pro, CAT and H2O2, and CAT and TPC; a perfect negative correlation between TPC and H2O2; and for others parameters nonsignificant correlation were observed under water-stressed conditions. © 2018, NAAS (National Academy of Agricultural Sciences).