Weather Variables Associated with Infection of Tomato Fruit by Colletotrichum coccodes

Area of Science:

• Plant Pathology
• Agricultural Meteorology
• Mycology

Background:

• Tomato anthracnose, caused by Colletotrichum coccodes, is a significant fruit rot disease affecting tomato production.
• Understanding the environmental factors influencing disease development is crucial for effective disease management strategies.

Purpose of the Study:

• To investigate the relationship between tomato anthracnose incidence and various weather variables.
• To identify key meteorological factors that predict disease development in field conditions.

Main Methods:

• Field experiments were conducted using potted tomato plants exposed to natural conditions over 4-day intervals during the 1993 and 1994 growing seasons.
• Disease incidence was assessed and correlated with meteorological data, including rainfall amount, duration, and hours of no rainfall.
• Regression analysis was employed to determine the best predictive model for anthracnose incidence.

Main Results:

• Rainfall variables, particularly the duration of dry periods, showed a strong correlation with anthracnose incidence.
• The most significant predictor of disease incidence was the number of hours without rainfall (HNRo) within the 4-day exposure intervals.
• A regression equation incorporating HNRo explained 72% of the variation in transformed anthracnose incidence.

Conclusions:

• Periods of dry weather are critical in limiting the incidence of tomato anthracnose.
• The number of hours without rain is a key factor for predicting and potentially managing this disease.
• Findings provide valuable insights for developing weather-based disease forecasting and management strategies for tomato crops.