brown spots on mango leaves

Caleb (Staff) says...
Hi APK,

It can be very difficult to diagnose these things, especially from photos, so bear in mind that I could be wrong here.

There don't appear to be any fruiting body type developments in the center of the spot, so probably not fungal.

I would expect damage to the leaf, tearing, holes all the way through or distinct burrow/borer tracks if it was insect.

I propose bacterial or chemical burns. If it is growing larger in an expanding dot, cut off the affected leaves to stop the spread. If the leaf tip starts dying behind the spot, then it is probably chemical burn and has killed the vascular tissue within the space but shouldn't do much damage beyond that leaf.

Thanks
- Caleb from Daley's Fruit Tree Nursery