I have a fig tree in my flat and some white spots have appeared and get more and more numerous and spread more and more over the leaves. It is not removable when rubbing with a tissue.
I can't find what it is, it does not seem to be common on fig tree! I'm suspecting mildew but it does not look like this exactly or that. It also look like the results of the move of an tiny worm inside the leave, but it is not so similar.
Also, the down face of the leave is brown where the white spots are located on the up side (see picture).
Any idea what it is from the picture below please?
Additional information:
- I regularly water the plant with vermicomposting juice
- The tap water is not especially mineralized here
- the soil is covered with marble pebbles