Mango disease: Dieback disease

Mango decline or dieback is a serious disease of mango. Dieback of mango is very destructive disease caused by Lasiodiplodia theobromae.

L. theobromae, however, it has been reported as the causal agent in destroying mango orchards within days or a few weeks of infection in India, USA, Pakistan, Brazil, Oman, and Korea. L. theobromae is a soil-borne wound pathogen that can affect all parts of the mango tree at all ages.

The L. theobromae occurs in about 500 plant species. The fungus is typical of tropical and subtropical regions and is easily disseminated by wind, insects, and pruning tools. At favorable conditions, the pathogen infects the plant branch, causing dieback and/or canker diseases, sometimes reaching the trunk, and even causing plant death.

The fungus, L. theobromae, often invades twigs and branches from their tips of mango trees causing them to dry and the plant to wilt. Symptoms at early stages of the disease included general wilting appearance of mango trees, and dieback of twigs.

In advanced stages, the disease symptoms were also characterized by the curling and drying of leaves, leading to complete defoliation of the tree and discolouration of vascular regions of the stems and branches.
Mango disease: Dieback disease

Black spot of mangoes

Black spot is the most important disease of mangoes in regions where this fruit is grown commercially.

Anthracnose or black spot caused by the fungus colletotrichum gloeosporiodes is usually appears in the fruit only as it ripens.

It develops in all tender parts of the plant and is especially severe on the flower and flower stems. The spots first appear as a very small brown area that enlarge rapidly and become black.

Often the entire fruit surface is covered by the coalesing of the spots. The affecting areas usually crack and sink slightly.

Mangoes are also susceptible to black spot disease, the agent of which is Alternaria alternate.

Control may rely on benomyl, prochloraz or a variety of other fungicides. Hot water dips with or without fungicides for 2-5 minutes have been quite affective in control of anthracnose and stem end rots in mangoes.
Black spot of mangoes