1
point
What is wrong with my mango trees?

Mango    None Given

Both mature as well as young mango saplings on my farm appear to be affected by some kind of fungus. Additionally , some kind of black waxy layer appears to have been formed on the leaves of the mature trees. Please suggest treatment.


Posted by: Abhishek (1 point) Abhishek
Posted: March 18, 2016


deactivated commented,
those look like Wooly Aphids to me. They leave white residue behind and attack all sorts of trees and plants. I would clean up that leaf debris on the ground what ever disease attacked your tree may continue if it gets absorbed in the soil. Also Ivy will suffocate your plants, Ivy should be destroyed and disposed.
about 3 years ago.



Answers

0
points
The white waxy layer (image 1 and 2) on your mango tree is mealybug (Drosicha sp.). Mealybug is an major insect pest in mango. Both nymphs and adult female suck the sap from tender leaves, shoots and inflorescence. The severe infestation leads to wilting and affects fruit setting.

Mealybugs secretes honeydew (a sugary substance) which causes sooty mold (image 3, 4, 5 and 6). The infected leaves and inflorescence become shiny black and sticky because several species of fungus which grows on this honeydew. Though sooty mold don't infect plants directly, they may reduce photosynthetic activity in leaves. So the infected plant may show stunting and leaves may die and fall off prematurely.

Management of sooty mold:
You can spray starch to control sooty mold.

Management of mealybugs:
1. Collect and burn fallen leaves and twigs.
2. Mealybugs lay eggs in soil near tree trunk. So flooding orchard with water during October kills egg. Also deep ploughing in November exposes egg to sunlight.
3. After hatching the nymphs start climbing tree and suck sap. To avoid this band the tree trunks with polythene sheet (400 gauge, 30 cm wide) at a height of about 30 cm from the ground level and apply grease at the lower edge of band. Or you can use Funnel Type Slippery Trap (image attached).
4. To control insects already on tree you can spray fish oil rosin soap or azadirachtin (neem products).
5. Also soil application of the spores of the fungus, Beauveria bassiana helps in reducing mealybug population.
6. If infestation is severe you can spray carbosulfan (0.05%, 25 EC, @ 2 ml/liter of water) or dimethoate (0.06%, 30 EC @ 2 ml/liter of water).


Posted by: Dr. Ravishankar Narayana (10 points) Dr. Ravishankar Narayana
Posted: March 18, 2016


Abhishek commented,
Thanks. I am grateful.
over 3 years ago.



0
points
Spray a mixture of Hydrogen Peroxide and Water. 1 cup to 1 gal. Mix in neem oil 1 1/3 T spoon and 1T dish detergent. Use warm water.


Posted by: Seyla (6 points) Seyla
Posted: April 2, 2016




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