Biotization of tissue culture banana plantlets with Methylobacterium salsuginis to enhance the survival and growth under greenhouse and open environment condition

Aim: This study aimed to investigate the impact of M. salsuginis TNMB03 biotization on tissue culture banana cv. Grande Naine plantlets growth and survival under greenhouse and open environmental condition (exposed to direct sunlight). Methodology: Banana plantlets were transferred from culture flasks to protray and maintained under the greenhouse and open environmental condition for 30 days with or without M. salsuginis TNMB03 treatment. After 30 days, plant growth parameters like pseudostem height, girth, number of leaves, leaf area, fresh and dry biomass, root parameters, plantlet survival, chlorophyll a and b, total chlorophyll, carotenoids and soluble protein and Methylobacterium population in upper and lower surface of leaf, as well as endophytic population were assessed. Results: This study showed that the plantlets biotized with M. salsuginis TNMB03 had better acclimatization response under both the experimental condition than that of uninoculated plantlets. Positive influence on the survival and growth of M. salsuginis TNMB03 biotized plantlets was observed when transferred directly to greenhouse and open environmental condition. Inoculation of M. salsuginis TNMB03 increased the plant height, girth and number of leaves, root length, lateral root and biomass in comparison to the uninoculated plantlets in greenhouse and open environment. Uninoculated plantlets kept under open environment had lower chlorophyll content and sun scorching damages compared to M. salsuginis TNMB03 inoculated plants, which had dark green leaves and increased chlorophyll content. Interpretation: This study shows a new potential technique of using M. salsuginis TNMB03 in tissue culture plantlets, which can help in enhancing the growth of plantlets transferred from culture vessel to greenhouse or open environmental condition without undergoing the routine acclimatization procedure.