AshEse Journal of Agricultural Science
Vol. 3(4), pp. 117-126, November, 2020
© 2020 AshEse Visionary Limited
Full Length Research
Biological Control ofErwinia Amylovora in Apple Trees Employing Antibacterial Agents
Jesús Garcia Pereyra1*, Gabriel Nicolas Aviña Martínez1, Sergio De los Santos Villalobos2, Ana Maria Garcia Montelongo1, Gabriel Alejandre-Iturbide3 and Rosa Bertha Rubio Graciano1
1Tecnológico Nacional de México, Campus Valle del Guadiana Durango, Dgo, Mexico
2Instituto Tecnológico de Sonora, Cd. Obregon, Sonora, México.
3Instituto Politecnico Nacional CIIDIR-Unidad Durango, Mexico.
Received Date: September 2020; Accepted Date: November 2020
The northern Mexican state of Durango has two major fruit producing sectors located in the municipalities of Canatlán and Nuevo Ideal, with a height of 1859 m above sea level. Even though these fruit producing zones encompass over 12 thousand hectares, the overall fruit production has been declining over the years. Two decades ago, the annual fruit production was approximately four million crates, by 2018; the production has been reduced by up to 75%. The decline in production is attributed to diverse environmental, cultural and economic factors, being the most important; environmental temperatures above 30°C during the flowering stage, which increases the proliferation of Erwinia amylovora bacteria, the causative agent of the fire blight disease. Infected plants exhibit damaged roots, leaves and fruits, necrotic lesions, reduced vegetative and floral bud sprouting, deficient accumulation of chill hours and fertilization, and irrigation during flowering stage are only a few causative agents that promote the presence of the bacteria, making it hard to control. Local producers have employed antibiotics (such as streptomycin) and cooper sulfate to control Erwinia infections, nonetheless, recurrent use of this agents have promoted the emergence of resistance. Taking this into account, the next activities were performed with the aid of local producers: eight orchards were selected within the localities of Canatlán, Durango, over 350 fruit trees with visible fire blight symptoms were marked, georeferencing, soil and stem sampling, soil fertility analysis, bacteria isolation using King B®selective medium, and Metarhizium anisopliae, Beauveria bassiana, Estreptomyces coelicolor and Bacillus thuriengiensis bioformulation using a 1 x 109 spores per gram proportion. Soil analysis revealed deficient organic matter, with values below 1.5%, alkaline pH values above 7.5, sandy texture and insufficient nitrogen and phosphorousin 75% of analyzed orchards. More than 90% of analyzed orchards presented E. amylovora in both soil and tree bark after a 72-hour incubation period. Employment of bioformulations for fire blight control revealed that only the B. thuringiensis bioformulation was able to control the disease with 95% efficiency after a single administration.
Keywords: Erwinia amylovora, Bacillus thuriengiensis, apple tree, soil fertility