Bacillus licheniformis M2-7 IMPROVES GROWTH, DEVELOPMENT AND YIELD OF Capsicum annuum L.
Plant growth promoting bacteria are known to directly or indirectly influence the development and yield of plants. Studies that show the biotechnological potential of these bacteria as biofertilizers are thus important. The objective of this study was to evaluate the growth capacities of strains M2-7 and LYA12 and define whether their interactions with Capsicum annuum L. increases production. The hypothesis was that the Bacillus licheniformis strains have capacities to promote growth and yield of Capsicum annuum L. First, these strains were evaluated in vitro in selective culture media to detect those direct or indirect mechanisms for plant growth promotion. Then, the effect of both strains on seed germination and the effect of strain M2-7 were studied on the in vivo development of C. annuum L. The experimental design was completely randomized with 3 treatments and 3 repetitions. Data was analyzed with ANOVA and Tukey test (p≤0.05). Results showed that the bacterial strains were able to fix nitrogen, solubilize tricalcium phosphate Ca3 (PO4)2, produce gibberellins, lytic enzymes (amylases, proteases, lipases and esterases), biosurfactants, volatile compounds; and significantly inhibit growth (p≤0.05) of the phytopathogenic fungus Colletotrichum sp. Likewise, the strains M2-7 and LYA12 increased (p≤0.05) by 89 and 78% the seed germination of C. annuum L. M2-7 enhanced fresh weight (235%), stem diameter (308%), root weight, number and weight of fruits (316%), as compared to treatment 1 (Nitrofoska) and 3 (Control). Therefore, B. licheniformis M2-7 strain is attractive to develop the formulation of biofertilizers; aiming to improve yield of some horticultural crops towards a sustainable and ecological agriculture.