Unique silvering of the leaves is the characteristic symptom induced by feeding of immature stages of silver leaf whitefly which releases a toxin inducing the unique pattern on the leaves.
Developing leaves have a silvery appearance from the leaf veins and moving outward. Heavy feeding of whiteflies can cause complete silvering of the leaves.
A close-up of symptoms of silvering on an affected pumpkin leaf. Symptoms of silvering is normally seen in summer or fall cucurbit production in Florida when whitefly numbers are very high.
Natural appearance of leaves on an unaffected pumpkin leaf. These leaves show light markings by veins which are natural and the extend of which may vary between different varieties.
Complete leaf silvering on squash leaves. Period of harvesting of cotton and peanut also is a typical period in north Florida when silvering is noticed more in cucurbits due to movement of whiteflies.
Large patches of silver leaf developing in a commercial field. The symptoms are also common in areas with non-maintained crops with high silver leaf whitefly persistence.