Effect of Azotobacter and Pseudomonas inoculation on microbiology of rhizosphere soils of Okra

Abstract

An experiment was carried out involving characterization of Azotobacter and PSB inoculations applied for enhancing growth performance of okra (Abelmoschus esculentus).Variety- Suraksha. The experiment was laid out in green house with six treatments and four replications. Treatments consisting of T1 (100% NPK), T2 (100% NPK + Vermicompost), T3 (75% NPK + Vermicompost + PSB), T4 (75% NPK + Vermicompost + Azotobacter), T5 (75% NPK + Vermicompost + Azotobacter + PSB), T6 (50% NPK + Vermicompost + Azotobacter + PSB). Both the isolates showed positive reaction for starch hydrolysis, catalase test. TSI test showed glucose, lactose and sucrose fermentation occurred with Azotobacter whereas in PSB no fermentation was seen. The results showed that the treatments T5 and T6 produced significantly highest growth of okra and better microbial property of rhizosphere soils of okra. Significantly highest PSB and Azotobacter population density in rhizosphere soil of pot grown okra was observed (21.14 X 104 and 48.54X 104 per g of soil ) due to (T5) followed by T6. Dual inoculation with Azotobacter and PSB treatments also showed maximum dehydrogenase activity in rhizosphere soils of pot grown okra in green house condition. Both the treatments showed significant effect on okra over rest of the treatments.