Positive effects of a formulated microbial consortium on the growth and well-being of okra and tomato crops

Abstract

The impact of microbial consortium (MC) comprising plant development-promoting organisms (PGPMs), for example, Bacillus sp., Enterobacter sp. (bacteria), Aspergillus sp., Penicillium sp. (fungus), and streptomycin sp. (actinomycetes) which are effective on two vegetable crops (okra and tomato). These strains were collected from five geologically isolated soil samples of agricultural fields around Bhubaneswar, Khurda, India (20.65946°N, 86.75409°E) and were biochemically characterized. The promising isolates were confirmed by 16s rRNA sequence. The MC was applied at five different concentrations, viz., 0.2%, 0.5%, 1.0%, 1.5%, and 2.0% (v/v using MS medium) along with a control were included. The combinations of above mentioned PGPMs strains significantly increased shoot height, plant height, leaf length, and leaf width at three-day intervals, and fresh weight, dry weight, and root length at the end of the study period. The results revealed that the protective effect of MC significantly increased all the parameters. The crop growth parameters were confirmed MC was effective when tested against control crops. The MC was more effective with the soil base than without a soil base. Among different concentrations of MC, 0.5% of MC was more effective for all the test crops as compared to other concentrations. So, 0.5% was optimal for microbial colonization to ensure the provision of soil nutrients, as no discernible change in growth parameters was observed to further increase in concentration. Also, a study on microbial and physicochemical parameters of all the treatments of all the crops was recorded. The lab study is a small-scale investigation to confirm the efficacy and the sustainability of MC in with soil and without soil of Odisha. Overall, the study illustrated a healthy biotic (consortium microbes and natural soil microbes) and abiotic (MS medium and soil supplement) interaction is advantageous for crop development and advancement.