Mango trees produce delicious fruit with a unique tropical flavor that some consider unrivaled. However, the mango tree's delicious fruit comes at a price. Mango trees are susceptible to a number of diseases that can strike at any point of their life and attack nearly any part of the plant. If you want your mango tree to successfully mature to bear healthy, attractive and edible fruit, you must constantly monitor it for disease. The most successful treatments are those that are applied when the disease first presents itself. However, take care to accurately identify the disease before applying any treatment.
Treat powdery mildew. Powdery mildew is one of the most damaging diseases that affects mango trees. The white powder that is the primary symptom of the disease can cover leaves, flowers or fruit and eventually cause early fruit drop and crop loss. Spray affected trees with a 0.2 percent solution of wettable sulfur. Fifteen days later, spray with 0.1 percent mixture of tridemorph. And then 15 days after that, treat the trees with a 0.1 percent mixture of dinocap.
Treat Anthracnose. Anthracnose is another common disease of mango trees. This disease can produce leaf spots, kill young blossoms, shoots and branches and even rot fruit. As soon as you spot anthracnose on your mango tree's blossoms, spray the tree with two treatments of a 0.1 percent mixture of bavistin at 15-day intervals. To treat anthracnose on your mango tree's foliage, spray it with a 0.3 percent copper fungicide solution.
Treat die back. Die back first darkens bark. As the disease progresses, twigs and branches wither and dry and the leaves drop off the tree. Treatment for die back is most effective when the disease is caught during the bark darkening stage. To treat die back, prune the affected branches two inches past the affected section. Then spray the entire tree with a 0.3 percent solution of copper oxychloride.
Treat bacterial canker. Canker disease attacks several varieties of mango and can cause leaf and fruit drop, total crop loss and even storage rot. The disease appears as moist "boils" (on any part of the tree or its fruit) that later turn into cankers. If caught early, bacterial canker can be controlled with three treatments of a 100ppm solution of streptocycline or Agrimycin-100 given at 10-day intervals.
Treat red rust. Red rust disease is caused by an alga that manifests early as greenish gray spots on the leaves that eventually turn into in rusty-looking red spots. Treat red rust disease with two applications of a 0.3 percent solution of copper oxychloride administered 15 days apart.
Treat sooty mold disease. Sooty mold forms on the residue of insects like aphids, scale insects and mealy bugs that excrete sticky residue onto the leaves. Sooty mold will continue to recur unless you get rid of the underlying pest problem. In the meantime, prune the affected foliage.