GROWTH-PROMOTING Streptomyces spp. STRAINS: A DIFFERENTIAL INTERACTION WITH VARIETIES OF COMMON BEAN UNDER FIELD CONDITIONS

Abstract

Common bean production faces adverse conditions, such as pests and diseases, climatic factors, and increased use and cost of agricultural inputs, which reduce both yield and productivity. Plant growth-promoting bacteria have been shown to enhance crop production. Streptomyces lasiicapitis (B22) and S. neyagawaensis (B31) are two strains with antagonistic and plant growth-promoting characteristics. The objective of this study was to characterize the induction of increased biomass and yield in two black bean cultivars, Verdín and Jamapa, through the application of strains B22 and B31 under field conditions. The interaction analysis revealed that, with respect to the control, Verdín showed positive interactions with both strains, with significant increases in plant dry weight (103% with both strains); number of pods (131% with B22, and 141% with B31), seeds per plant (132% with both strains), and seed weight per plant (137% with both strains), while weight of 100 seeds showed a modest increase of 13% with B31. Jamapa cultivar exhibited a differential response, with a notable positive interaction with B31, resulting in increases in seed weight per plant and plant height of 23,5% and 16,6%, respectively. These results indicate that there was a significant promotion of growth and yield, although with a differential response between cultivars, especially in those related to plant biomass.