The Mango Decline Disease caused by the fungus Ceratocystis manginecans is a serious threat to mango crops worldwide. The economic impact of Mango Decline Disease is significant, as it reduces fruit yield, quality, and marketability and can result in the complete loss of orchards. The disease can spread through infected plant material, tools, and machinery and persist in the soil for many years.
The management of the disease is challenging, as there are currently no effective chemical controls available. However, cultural practices such as pruning, sanitation, and the use of disease-free planting material can help reduce the incidence and spread of the disease. In addition, research is ongoing to develop resistant mango varieties and biological control measures to manage Mango Decline Disease.
To effectively manage this disease, it is important to understand its disease cycle, the mode of disease spread, and the best methods for controlling it. This article will provide an overview and discussion of the Mango Decline Disease in Mango crops, including its symptoms, identification techniques, and control.
Mango Decline Disease Management
The Causal Organism of Mango Decline Disease
- Ceratocystis manginecans is a filamentous saprophytic fungus that belongs to the Family Ceratocystidaceae of Order Microascales of the Phylum Ascomycota.
- The fungus produces conidia and ascospores.
- The conidia are hyaline (transparent) and cylindrical, measuring 3-5 μm in diameter and 15-30 μm in length.
- The ascospores are hyaline, oval to cylindrical, and measure 5-7 μm in diameter and 10-20 μm in length.
The Disease Cycle of Mango Decline Disease
The disease cycle of the Mango Decline Disease, Ceratocystis manginecans, in Mango Crops begins with the infection of the mango tree by C. manginecans. The fungus can enter the tree through mechanical injuries or natural openings, such as stomata or lenticels, and colonize the vascular system. The fungus can also survive in dead plant tissue and soil for long periods, making it challenging to eradicate.
Once inside the tree, the fungus colonizes the vascular system, blocking water and nutrient transport. This results in wilting and yellowing of the leaves, defoliation, and eventual death of the tree. Colonizing the vascular system can take several years, and symptoms may not be visible until the disease progresses.
The conidia are produced in small clusters on specialized structures called synnemata, which emerge through cracks or wounds in the tree’s bark. The ascospores are produced within fruiting bodies known as perithecia, which are embedded in the infected tissue and visible as black dots on the bark.
The spores are dispersed by wind, rain, and insects. The conidia can be spread over short distances, while the ascospores can be carried over longer distances. The spores can also be spread through infected plant material, tools, and machinery. Secondary infections can occur through wounds or natural openings, such as stomata or lenticels.
Occurrence of Mango Decline Disease in Mango Crop
- Location of Mango Decline disease: This disease occurs in mango crops in India, Africa, Bangladesh, Sri Lanka, Thailand, the Philippines, the United States, Mexico, Brazil, and Australia.
- Host range: The most common crops affected by Ceratocystis manginecans are mango, avocado, papaya, coconut, jackfruit, and breadfruit.
Favorable Conditions for Mango Decline Disease Spread in the Field
- Warm and humid conditions are favorable for infestation. The optimal temperature for fungal growth is around 28-30°C and more than 70% relative humidity.
- The fungus can also colonize healthy tissues and cause disease while the tree is under stress, such as during a nutrient deficien