leaf curl

[the999bbq]

Every year there are some plants that show a bit of leaf curl but this year it is massive (PL varieties tend to do better). Is there a definite way to distinguish physiological leaf curl from viral leaf curl (yellow leaf curl,...). The lower leafs do show some yellowy blocks between the veins, but then again for an amateur like me magnesium deficiency+physiological leaf curl could equal yellow leaf curl symptomwise...

Flowers appear normal and the do form fruit (for the time being?) so should I worry for this year's crop ?

Outdoor plants don't seem to have this problem at all - they are smaller than the greenhouse ones, planted practically at the same time though, and they get the same regime in pruning (no extra watering/feeding - watering regime for the greenhouse toms is once a week, about 1,5 liter per plant, one tablespoon of molasses per 50 liters of water; that was my experiment for the year : can you get results only by this feed)

the greenhouse is moved to clean soil every year, it just follows my overall rotation scheme on 9 patches.

No insects visible under the leafs nor 'inside' the curl. no whitefly spotted yet...I think

what are my options here ? should I go back to my 'normal' fluid tomatofeed and hope it is physiological leaf curl ?



Peter