Viability of beneficial bacteria for the control of Mycosphaerella fijiensis and development of banana plants

Abstract

Organic banana production is affected by various diseases, with black Sigatoka (BS) (Mycosphaerella fijiensis Morelet) being one of the most important, as it reduces leaf functional area and decreases production. Organic alternatives to counteract the effects of the disease are scarce, leading to a loss of fruit quality for export. An organic alternative to reduce this disease is the use of native plant growth-promoting bacteria (PGPRs). The purpose of this research was to analyze the feasibility of inoculating PGPR bacteria to control BS in organic bananas in Esperanza, Valverde, Dominican Republic. To achieve this objective, an experimental field plot was established using a randomized complete block design, where three treatments with PGPR bacteria were evaluated: DARA (Bacillus licheniformis), MAM21 (Pseudomonas plecoglossicida), MOSY (P. plecoglossicida), and a control without bacteria. Each treatment had four replicates, with a 2x2 m planting frame with a useful area of 10 plants per treatment for data collection. Each plant was inoculated with 20 cc of inoculum at an approximate concentration of 6X108 colony-forming units per milliliter (CFU m l^-1). Cultural tasks were carried out according to the requirements of the crop and the producer. The results of the variables evaluated for NS demonstrated a decrease in the severity of the disease in the three treatments with PGPR bacteria. The MOSY21 treatment obtained the best results, showing a decrease in the effects of the disease; as well as in some variables indicating plant development and in variables related to productivity. This research showed that PGPRs help plants, in their development, defend themselves against diseases and productivity.