Microbial bioinoculants on agronomic and physiological characteristics of chiltepín, glabriusculum variety

Resumen

Objective: This study aimed to evaluate the effects of Bacillus subtilis and arbuscular mycorrhizal fungi, applied individually and in combination under conventional and organic management, on agronomic, physiological, and microbiological variables of chiltepín cultivated under open-field conditions.

Design/methodology/approach: The experiment was conducted under open-field conditions with mulch, using a randomized complete block design with eight treatments and three replicates. The treatments consisted of individual and combined applications of Rhizophagus irregularis (BLACK RAY) and Bacillus subtilis (Bio Booster), applied via drench every 15 days at a dose of 5 mL per plant. Agronomic, physiological, and microbiological variables were assessed, including plant height, stem diameter, SPAD units, fresh and dry biomass, root length, percentage of mycorrhizal colonization, and the number of spores per 100 g of soil. Results: The results revealed that the combination of arbuscular mycorrhizal fungi and Bacillus subtilis under conventional management promoted the greatest accumulation of total dry biomass, as well as the highest values of spore density and mycorrhizal colonization. Plant height and stem diameter did not exhibit significant differences among treatments. Overall, treatments involving microbial consortia outperformed individual applications, particularly when integrated with conventional fertilization. Study limitations/implications: Chiltepín (Capsicum annuum var. glabriusculum) is a wild species currently undergoing domestication, a process associated with high phenotypic and physiological variability. This condition may influence crop response to the application of microbial bioinoculants and to the management schemes evaluated, thereby limiting the uniformity of the observed responses and underscoring the importance of considering this biological characteristic when interpreting the results. Findings/conclusions: The results indicate that the combined application of microbial bioinoculants enhances root system functioning and nutrient uptake efficiency in chiltepín, thereby demonstrating the potential of microbial consortia as a biological management strategy for this crop.