Anthracnose
Glomerella cingulata
What is Anhracnose (Glomerella cingulate)?
Glomerella cingulata, also known as Colletotrichum gloeosporioides, is a fungal pathogen commonly associated with the disease known as " anthracnose". It can cause anthracnose in multiple crops, including mango, avocado, capsicum, coffee, eggplant, papaya, tomato, and yam. Different strains of the fungus can infect specific crops and even weeds. The fungus causes severe damage in wet weather, including flower blight, shoot dieback, leaf spots, fruit rots, and storage losses.
How does Anhracnose (Glomerella cingulate) occur?
The fungus produces many spores within the spots. These spores are spread to other leaves, flowers, and shoots when they are splashed by rain. Once they land on new surfaces, the spores germinate, infect the plant, and create more spots and blights. Young leaves are particularly vulnerable to infection. Initially, the spots are small, black, and irregular, but they often grow and merge to form extensive dead areas that eventually dry up and fall off. When the fruits reach maturity, the fungus remains a tiny infection until the fruit ripens. At that point, the infections develop into dark brown to black spots with orange-pink masses of spores.
Symptoms
1 - Impact on Plants
Anthracnose caused by Glomerella cingulata can lead to various detrimental effects on plants. The disease can cause leaf blight, defoliation, premature leaf drop, and fruit rot. Severe infections can result in reduced plant vigor, stunted growth, and diminished crop yield and quality.
2 - Health
Glomerella cingulata produces spores that can infect plant debris and fallen infected fruits on the soil surface. This can lead to soil inoculum buildup, increasing disease pressure in future growing seasons.
3 - Impact on the Environment
• Glomerella cingulata anthracnose can spread and impact the environment. Infected plant material can serve as a source of inoculum for nearby plants, affecting cultivated crops and native species. • It can disrupt natural ecosystems and compromise the health and survival of native plants.
Solutions
1 - Prevention
1. Choose resistant or tolerant plant varieties when available. 2. Remove and destroy infected plant debris to reduce the source of inoculum. 3. Avoid overwatering and minimize leaf wetness to create an unfavorable environment for the fungus. 4. Pruning: Maintain good airflow by pruning and thinning plants to promote drying and reduce humidity. 5. Implement a comprehensive IPM program, combining cultural, biological, and chemical controls to manage the disease effectively.
2 - Treatment
To manage Glomerella leaf and flower blight, regular and timely use of chemical treatments like copper oxychloride, carbendazim or mancozeb is crucial. Apply fungicides according to labeled instructions, considering the specific crop, stage of growth, and disease severity.
