Efficiency of 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase containing Pseudomonas fluorescens as plant growth promoting rhizobacteria for enhancement of growth and yield of maize (zea Mays L.)

The present investigation was carried out at J.N.K.V.V. Jabalpur during Jaid season of 2019. The present study aims at characterizing efficient ACC deaminase containing P. fluorescens isolates with plant growth-promoting activity isolated from fermentor under different temperature and pH (Temperature: 25, 28, 31, 34⁰ c and pH 6.7, 7.2, 7.7, 8.2). Results indicated that treatment combination T₂₈+pH 7.2 (Temp 28^oC+pH 7.2) isolates significantly enhanced the emergence (31.1 and 28.7%) at 5 and 9 DAS, respectively, and the isolate of T₃₁+pH 7.2 significantly emergence 30.8% at 7 DAS over that of control. The treatment combination T₃₁+pH 7.2 significantly increased No. of roots, length of roots, 30.0 and 22.5%, respectively at 55 DAS and (T₂₈+pH 7.2) isolates significantly increased fresh weight and dry weight of brace roots (25.0 and 26.2%) over that of control. The isolates of P.fluorescens (T₃₁+pH 7.2) at 75 DAS significantly increased (30.2, 28.1 and 25.7%), respectively no. of brace root, brace root fresh and dry weight and rhizobacterial isolates P.fluorescens (T₂₈+pH 7.2) significantly increased root length of maize when compared with the control. The plant height were obtained with isolates T₃₁+pH 7.2 by (29.3 and 29.1%) at knee height and silking stage and T₂₈+pH 7.2 at tesseling stage by (31.1%) respectively, increased over FUI. Application of P.fluorescens (T₂₈+pH 7.2) accounted for maximum number of leaves at knee height and silking stage and T₃₁ + pH 7.2 at tesseling stage by (32.6, 27.2 and 31.1%) significantly increased number of leaves. The application of isolate (T₂₈ + pH 7.2) which yielded 11.8, 13.3 and 21.7% higher total chlorophyll than uninoculated control. The application of isolate (T₂₈+pH 7.2) which yielded 19.2 and 28.0% higher fresh weight at knee height and silking stage respectively, at tesseling stage the response of P.fluorescens (T₃₁ + pH 7.2) isolate which yielded 26.6% higher fresh than FUI. The application of isolate (T₂₈ + pH 7.2) which yielded 24.6 and 26.3% higher dry weight at knee height and silking stage respectively, at tesseling stage the response of P.fluorescens (T₃₁ + pH 7.2) isolate which yielded 23.8% higher fresh than FUI control. The treatment combination T₂₈ + pH 7.2 significantly increased the grain (24.9%) and stover yield (31.6%) of maize over that of control.