My arabian jasmine plants have these yellow spots on the leaves. These appear as a few tiny speckles on a leaf and then slowly (in about a week ) expand to large spots that eventually cover all the leaf. The leaf then dries out and falls off.
I tried to preemptively cut off the leaves that have this problem, and also trim the spotty areas off some leaves but I have observed that once a leaf is inflicted with this, it is eventually wasted, even if I cut off the spotty region. Every week, 4-5 leaves are wasted with this problem.
The plants are small, I am worried that this problem might overwhelm the plants.
The plants are otherwise flourishing. Most of the leaves are healthy and strong. New leaves and flowers grow regularly. I water the plants every day or on alternate days, just making sure that the top of the soil doesn't get dry.
What are these yellow spots and how can I help my plant against them?
Edit: I live in Punjab, Pakistan. The weather is warm to hot most of the year. The plants are in a fruits crate lined with plastic sheet and filled with local soil. The plants don't come under any shadow at any time of the day. Picture is attached.