Bioprospecting of endophytic bacterial inoculation in intercropped Trillium govanianum (Wall. Ex. Royle) and Apple cv. Royal delicious

Intercropping is a crucial soil management strategy for boosting orchard productivity. This study explores the cultivation of Trillium govanianum within an integrated apple farming system in the Indian Himalayan region. Three plant growth-promoting endophytic bacterial strains—Pantoea spp. Ar13, Microbacterium spp. Ar17, and Pseudomonas spp. Ms5—were isolated and identified from the rhizomes of T. govanianum. These strains were used individually and in consortia to create a charcoal-based bioformulation. A field experiment was conducted in a 10-year-old apple orchard to evaluate the effectiveness of the bacterial bioformulation. The bioformulations were applied alongside a reduced dose of chemical fertilizer (NPK) to assess their impact on apple growth characteristics, while no chemical fertilizer was used with T. govanianum. Results indicated that the bioformulation containing a consortium of Pantoea spp. Ar13, Microbacterium spp. Ar17, and Pseudomonas spp. Ms5 significantly increased the plant height (4.04 ± 0.06 cm), leaf length (2.86 ± 0.03 cm), rhizome size, rhizome weight, and root length of T. govanianum compared to the uninoculated control. Additionally, the height (448.52 ± 0.63 cm), girth (24.58 ± 0.12 cm), shoot length (86.63 ± 0.77 cm), canopy (18.92 ± 0.05 m³), and yield efficiency of the apple trees were significantly improved with the inoculation of the consortium combined with 80 % NPK. Overall, the findings of this study suggest that inoculating with these endophytic bacterial bioformulations benefits the cultivation of T. govanianum and apples in an intercropping system. This has significant implications for producing bioformulations, especially in low-temperature environments.