Replacement of methyl bromide application by alternative methods in vegetables under cover

The use of methyl bromide (MB) as a soil fumigant will be withdrawn, worldwide until 2005 for health and environmental reasons. Grafting on resistant wild species and mulching with transparent polyethylene film 0.05 mm thick were studied instead as alternative methods to MB, for controlling Verticillium and Fusarium wilts of eggplant and melon, two of the most serious diseases for those crops. Eggplant seedlings cv. `Tsakoniki' and melon seedling F-1 were transplanted in a non heated plastic greenhouse, in 1999, and received the following treatments: control, methyl bromide fumigation with 68g/m(2), grafting eggplant on Solanum torvum and melon on `Shintosa' and-mulching. The disease severity was estimated by the Disease Index (DI) as the product of Leaf Symptoms Index (LSI) by Vascular Discoloration Index (VDI). In addition, the plant height, early and total commercial yield, fruit number of early and total commercial yield, and root weight were measured in both plant species. The total plant weight and root weight for eggplant and fruit diameter of external and cavity, thickness of pericarp and flesh, pH and (0)Brix for melon were also measured. The data indicated: (1) In eggplant the grafting and MB were significantly different compared to the control for most of the measured characteristics, while mulching was significantly different only in early and total yield and fruit number. (2) In melon mulching was significantly better than the other three treatments only in the early and total yield, fruit number and fruit external diameter. In conclusion grafting for eggplant and mulching for both crops could be used as alternative methods to MB.