[daigo75]

Hi all,
I just noticed today that one of my tomato plants is becoming more and more yellow, and I don't know what could be the reason. I have about a dozen of plants, some have yellow leaves at the bottom that I usually remove (they are in pots and grew as bushes, the bottom leaves don't get enough sunlight), but this plant is getting yellow everywhere. I didn't do anything "special" to it, same treatment as all the others.

Today I removed the oldest leaves and I found many rotten ones, hidden in the bush. I also noticed that the plant has many flowers, but not so many fruits (also thanks to the wind that "harvested" many tiny ones on my behalf).

In the soil I didn't spot any visible mold/fungus, I just found two slugs, some little bugs I couldn't identify, and some adult earwigs, but I don't know if any of them could be responsible.

Any help is greatly appreciated. Thanks.

[michael brenock]

when only one plant turns yellow the more likely cause is a pest rather than soil or climatic conditions. The lower part of the stem might be attacked by pests including slugs. Botrytis or grey mould may be on stem or if fruit is also dropping off then it might be didymella stem rot. Older leaves turn yellow because of shortage of magnesium but unlikely to occur in a single plant. If the leaves are wilting as well as going yellow then there is a root problem such as Rhizoctonia or didymella or some other root disease.
michael brenock horticultural advisor (retired)

[daigo75]

Quite complicated, then... Is there anything I can do, or should I just dispose of the plant?

[michael brenock]

leave the plant there and let the fruit develop more and ripen then dispose of it and examine the roots and stem for any peculiarities and let us know th result.
michael brenock horticultural advisor (retired)

[daigo75]

Ok, I'll try. Thank you very much