AVALIAÇÃO DO DESENVOLVIMENTO VEGETATIVO PROPORCIONADO POR Bacillus methylotrophicus E BIOCONTROLE DE DOENÇAS NA ABOBRINHA ITALIANA.

Abstract

This study aimed to evaluate the interaction of Bacillus methylotrophicus with the initial vegetative culture of the plants, as well as to observe the initial vegetative development of the plants and the effect of the product on the main diseases of the culture, such as downy mildew (Pseudoperonospora cubensis) and powdery mildew (Sphaerotheca fuliginea), with the use of two different methods of application, via spraying with a bar and by application via the plant neck (drench), with the use of the biological product based on B. methylotrophicus, comparing with the chemical product already registered for the control of diseases (copper hydroxide). The trial was conducted in the experimental area of the IF Goiano Campus Morrinhos. The experimental design was in randomized blocks, with five replications and four treatments, T1-control, T2- Bacillus methylotrophicus (1x109 CFU/mL, 5L/ha), applied to the soil (drench), T3- Bacillus methylotrophicus (1x109 CFU/ mL, 5L/ha) applied foliar spray, T4-copper hydroxide (Tutor®, 3.0 kg/ha). The plot consisted of five plants, five meters long, where the plants were spaced one meter apart. Applications began on the day of transplanting and then every seven days, thus weekly applications at 0 DAT, 7 DAT, 14 DAT, 21 DAT, 28 DAT, totaling five applications, using a 20-liter backpack sprayer with a flow of 500 L. /ha, and a three-liter adaptable sprayer for application via drench. The evaluations of severity and vegetative development started with 21 DAT, ending with 56 DAT, accounting for a total of six evaluations, for the variables root and green plant mass, three central plants were used, taking the average between them. The biological product applied via drench was significant in vegetative growth, providing a better initial development in plant growth, anticipation of flowering and production, shortening the window period for diseases, when applied via foliar it presented vegetative development and control over the disease when compared to the witness. Copper hydroxide provided better disease control, resulting in good productivity at the end of the cycle compared to other treatments.