Rhodotorula glutinis

Rhodotorula glutinis is a species of yeast-like fungus that is widely recognized for its ability to produce carotenoid pigments, resulting in distinct pink, orange, or red colonies. While it is often found in nature as a harmless saprophyte, it can act as a pathogen under specific conditions, affecting the quality and integrity of various agricultural products during the pre-harvest and post-harvest stages.

The pathogen primarily attacks fruit, vegetables, and grain crops. It frequently exploits wounds or skin abrasions on the surface of harvested produce. By colonizing these vulnerable spots, the fungus accelerates tissue degradation and makes the crop susceptible to secondary infections by bacteria and other fungi, leading to severe spoilage in storage facilities.

Visible symptoms include the formation of slimy, colored patches on the surface of the affected plant tissues. These areas often appear moist and sticky, eventually turning soft as the cell walls of the plant are broken down by the yeast's enzymatic activity. An offensive, fermented, or sour odor is commonly associated with advanced stages of infection.

The development and spread of Rhodotorula glutinis are highly favored by high humidity levels and moderate temperatures. The presence of surface moisture, organic exudates, and physical damage to the plant tissue creates the perfect microenvironment for the pathogen to thrive and propagate, especially within confined spaces such as shipping containers or storage silos.

The impact of this pathogen on agriculture is significant due to post-harvest losses and reduced market value of the produce. Management strategies focus on sanitation and environment control. Essential measures include:

• minimizing physical damage to produce during harvesting;
• ensuring proper ventilation and moisture control in storage areas;
• sanitizing storage equipment and facilities regularly;
• removing damaged or infected produce early to prevent the spread of the pathogen.