Part 1: The Problem – Anthracnose and Colletotrichum spp.
What is anthracnose?
Anthracnose is a disease caused by fungi of the genus Colletotrichum. It affects various crops, manifesting as necrotic spots and rot on flowers, fruits, and leaves. In recent years, it has been detected in crops such as cocoa, plantain, avocado, blueberry, yucca, mango, and papaya. A recent example is Colletotrichum siamense, which was identified in cocoa in countries like Malaysia and Mexico, demonstrating that it is a pathogen of global significance (Abd & Mohd, 2023).
How does anthracnose affect crops?
The most concerning aspect of anthracnose is its ability to attack crops at various stages, including post-harvest, which reduces the shelf life of the products.
Economic losses can range from 50-100%, depending on the crop and climatic conditions (Rodríguez-Velázquez et al., 2025). This fungus thrives in humid and rainy climates, while its progression slows down during dry seasons. Its life cycle begins when spores are dispersed by wind, water, or insects, making it a constant challenge for farmers.
A practical example: a banana, cocoa, or mango farmer can lose the majority of their harvest in just a few days if heavy rains coincide with the fruiting stage.
A study in the province of El Oro revealed that cultural practices, such as proper pruning and the use of nutrients like silicon, copper, boron, and zinc, reduce the incidence of Black Sigatoka (Espinosa Suárez,2015. Repositorio UTMACH).
Figure 1. Morphological and microscopic analysis of Colletotrichum sp.
Visible symptoms of anthracnose in cocoa and microscopic observations of the causal agent (Rodriguez-Velázquez y otros, 2025).
For farmers, anthracnose represents not only economic losses but also uncertainty with every harvest.
What is happening in Ecuador?
In a recent study in the provinces of Guayas and Azuay, several species of Colletotrichum were identified:
C. chrysophilum: caused mild symptoms.
C. siamense: showed greater aggressiveness.
C. fructicola: was found to be the most destructive (Espinoza-Lozano et al., 2025).
Until now, the most common control method has been copper sulfate pentahydrate, with results comparable to synthetic fungicides. However, this type of practice poses environmental and health risks and does not guarantee long-term sustainability.
Why is this fungus so complex?
The effect of anthracnose depends not only on the fungus itself but also on the plant host and the environment.
An illustrative case: C. acutatum survived on various crops (strawberry, eggplant, and tomato) but only caused disease in strawberries. This demonstrates that the same fungus can colonize many plants but may only severely affect a few (Newfeld et al., 2025).
In Summary
Anthracnose is more than just a simple fungus on crops:
- It can drastically reduce production and quality.
- It spreads easily in humid environments.
- It represents a particular challenge for Ecuadorian farmers.
For all these reasons, anthracnose remains one of the main challenges for sustainable agriculture in Ecuador and around the world.
BioNaturaleza: Visible Science at the Service of the Producer
At BioNaturaleza Biotech, we research and develop bio-inputs that respond to this type of challenge—controlling anthracnose in cocoa—always with a scientific basis and applied in the field.
In Part 2 of this series – Colletotrichum spp. in Ecuador – we will explore sustainable alternatives to face this problem: from reducing the use of fungicides to the role of biocontrol agents and biotechnology applied in the field (sustainable management of anthracnose).
