Hay bacillus

Hay bacillus (Bacillus subtilis) is a gram-positive, spore-forming bacterium of the genus Bacillus. While often regarded as a beneficial agent in agricultural science, specific strains can act as opportunistic phytopathogens, causing soft rot and degradation of vegetable and fruit tissues, which poses a significant threat to post-harvest storage.

In terms of systematics, the organism belongs to the phylum Firmicutes, class Bacilli, and order Bacillales. As a pathogen, it is recognized for its ability to produce potent exoenzymes that break down the pectin layers of plant cell walls, leading to rapid tissue decay and secondary infections in agricultural commodities.

The primary damage caused by this pathogen includes wet rots on crops like potatoes, carrots, and various pomaceous fruits. The infection typically starts in areas where the plant skin has been compromised by mechanical damage, insects, or environmental stress, followed by rapid bacterial colonization under warm and humid conditions.

The biology of the species is defined by its remarkable resilience. The formation of endospores allows the bacterium to persist in soil, agricultural debris, and storage facilities for years. Once favorable conditions—such as high moisture and moderate-to-high temperatures—are met, the spores germinate, and the bacteria begin to proliferate exponentially.

Effective control measures require an integrated approach to sanitation and post-harvest management.

• Sanitizing storage facilities before loading.
• Implementing strict temperature and humidity controls to minimize bacterial growth.
• Avoiding mechanical injury to produce during harvesting and handling.
• Regular inspection and removal of rotting materials to prevent cross-contamination.