Plant Diseases/Lemon tree disease
I have a lemon tree in my terrace (I live in Madrid, Spain), in a sunny position, well-watered and fed regularly. The leaves have started to curb at the edges, yellowing and looking a bit as if they were burnt, and the fruit buds are falling.
┐Could you please tell me what is wrong with it?
Thanks for your photos. From your images, I do not suspect an infectious disease. The faded areas and curling of the leaves may be a candidate for some environmental stress rather than a pathological or disease related issue.
The affected areas on the leaves may be related to a nutritional imbalance or a root malfunction in the plant or even a contact type injury from something applied/sprayed to the soil or directly to the leaves. You may consider having the soil tested for nutrient availability and reviewing any chemicals applied to the foliage. Watch the new leaves as they form for the same symptoms. If they look OK, then this fading and curling may be temporary. Also check closely on both sides of the leaves for any insects. You may also snip off a few affected leaves and show them to your local plant nursery or garden center for their comments since these folks may have seen these symptoms before.