Ameliorative Effect of Bacillus sp. MN-54 and Organic Amendments Combination on Maize Plants Growth and Physiology Under Chromium Toxicity

Inoculation of bacteria increase the growth of maize by facilitating the nutrients uptake and improving the immunity of plants and ability against pathogens, harmful substances such as heavy metals and other diseases. Likewise, organic amendments also increase the growth of plants by providing ample amount of readily available nutrients and improving soil physical conditions and ameliorating heavy metals toxicity. In this study, a pot experiment was conducted to evaluate the interactive effect of bacteria and organic amendments on Cr uptake and growth of maize irrigated with tannery effluent. Biochar and processed animal manure were applied at the rate of 1% (w/w). The experiment was conducted as Completely Randomized Design (CRD) with three replications. During the experiment various growth, physiological and biochemical parameters were measured by using standard procedures. Combination of Bacillus sp. MN-54 and low pH animal manure increased the plant height by 72%, chlorophyll content by 56%, water use efficiency by 68%, electrolyte leakage decreased by 51%, transpiration rate increased by 45%, RWC 57%, stomatal conductance 62%, photosynthetic rate 57% whereas Cr decreased the shoot growth by 45% over their control treatment. Overall the bacterial species evaluated in this study along with biochar and animal manure imparted heavy metal tolerance to maize plants evidenced by improved growth and physiology.