Fructophilic lactobacilli

Lactobacillus fructivorans is a specialized type of lactic acid bacteria that primarily acts as a plant pathogen causing tissue degradation in sugar-rich fruits. While often associated with spoilage in the winemaking industry, these bacteria can infect field crops, utilizing sugars within plant tissues for growth and causing rapid fermentation and decay.

The primary hosts for this pathogen include various fruit trees and berries, with grapes, apples, and citrus fruits being the most susceptible. The disease is particularly problematic during the ripening stages, as the softening of the fruit tissues provides an ideal environment for the bacteria to colonize and spread throughout the crop.

Symptoms of the infection manifest as localized softening of the fruit flesh, often accompanied by a distinct acidic or alcoholic odor. As the bacteria metabolize the sugars, they produce gases that cause the interior of the fruit to become spongy or hollow. In advanced stages, the skin may rupture, releasing an exudate that further spreads the bacteria to adjacent fruits.

The development of the disease is highly dependent on environmental conditions, specifically high humidity and temperatures between 20°C and 30°C. These conditions accelerate bacterial growth. The infection typically enters the plant through mechanical wounds, insect bites, or natural fissures that occur during the maturation process, making physical damage prevention a critical factor.

Effective management and prevention strategies include the following:

• Rigorous sanitation to remove fallen or decaying fruit from the orchard floor.
• Integrated pest management (IPM) to reduce insect damage that allows bacterial entry.
• Proper handling during harvest to minimize mechanical bruises and skin punctures.
• Storage of harvested produce in temperature-controlled environments to inhibit microbial activity.
• Application of copper-based treatments to maintain general plant health and lower the pathogenic load.