The White-fly (Bemisia tabaci) secretes honeydew that contaminates the cotton and makes it "sticky". The contaminated cotton sticks to machines in the gin and the spinning mill and produces poor yarn. This presentation summarizes a decade of work in Israel which has practically solved the stickiness problem but has never been published in detail outside Israel.

White-fly infestation increases both the physiological sugars (Ps) inside the fibers which are not sticky and the honeydew (Hd) upon the fibers which is sticky. U. Mor and A. Marani found that in very sticky cotton the Hd is 0.05% - .010% of the fiber's dry weight while the Ps is 0.25% - 2.00%. A study E. Kelter has proved that white-fly infestation and the stickiness, high Trs do is not necessarily mean stickiness and using the Trs as the only criterion for stickiness may be misleading. A method to distinguish between the Hd and the Ps is essential. Analysis of pure Hd vs. pure Ps which had been collected directly from the larvae and the fibers, was performed using HPLC, in the search for chemical constituents that can be used as marker, but without any success. The PH of the pure Hd is equal to that of the none- contaminated the pure Hd is equal to that of the none-contaminated cotton. PH difference and sugar markers which have previously been reported in the literature are presumably products of microorganisms which fed on the Hd and therefore associated with it.

A direct method that measures the stickiness using a minicard, has been developed by the Israel Cotton Board. The method, which is commercially used, is simple, reliable and has good repeatability (r=0.84).

The Stickiness Management in Israel consists of: 1. White-fly control in the field. 2. White-by infested fields which are suspected of stickiness are sprinkler-irrigated between the defoliation and the harvest. 25mm. water is applied. The water rinses the cotton and removes the Hd but almost does not penetrate the cotton, does not change the Ps and does not harm the fibers. 3. Ginning is performed as usual and samples are taken to the classing office. 4. All the samples are checked for Reducing sugars content (Trs). 5. Samples having high Trs are tested ont he minicard and sorted for stickiness. 6. Cotton bales whose samples are found to be sticky are separated from the rest and are sold as suspected of stickiness. 7. Stickiness suspected bales are processed at the destickiness plant. (This plant is only a pilot in December 1991)