Hello everyone, first time posting, but reading your posts for a long time.
And i come with a problem.
This problem appeared in a culture of Physalis Peruviana in greenhouse with a relatively high humidity of the air, strikes leafs that turn yellow and fall and fruits that fall prematurely.
If someone can help me to find the problem, whether it is a disease (Cercospora sp.), nutritional deficiency (phosphorus or nitrogen) or both. And what the solution in a bio method...
Physalis peruviana is a common garden plant in NZ, almost a weed in milder areas. We've got it all around the place and in our maritime temperate climate it's pretty robust, with the only pests being whiteflies and occasionally scale. It doesn't even seem to get eaten by the opportunistic looper that devours many of our other nightshades like tomatoes and eggplants. So, I don't grow it in my glasshouse and haven't seen this sort of trouble.
That next to last photo shows a leaf that might be chlorotic from low iron or manganese, but the discoloration is not very pronounced. The damage in the top photos reminds me of sunscald. Does the greenhouse get hot sometimes with a lot of direct sun? If the leaf surface overheats and the plant can't transpire effectively, tissue damage can happen and then a secondary pathogen such as a fungus can take hold. The spots in general look to be hallmarks of an infection, either fungal or bacterial, and this might be a result of high humidity and lack of air circulation.
Anyway, these are just guesses on my part. Maybe someone with more experience will chime in and have better answers.
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