Various Fenton solutions have been developed for advanced oxidation processes in wastewater treatment. In this study, conventional Fenton solutions such as hydrogen peroxide (HOOH) + Fe(2+) (Mix 1) or HOOH + Fe(3+) (Mix 2), and a new type of solution, HOOH + Fe(3+) + oxalic acid (Mix 3), were used as foliar sprays against powdery mildew on cucumber caused by Sphaerotheca fuliginea. Three Fenton solutions, plus a fungicide, fenarimol, were used to cure and/or protect the plant from powdery mildew under greenhouse conditions. Determination of the ·OH photoformation rate of these Fenton solutions revealed that Mix 3 had a photoformation rate 3.6 - 4.3 times higher than those of Mix 1 and 2. Application of fenarimol and Mix 3 to each plant once a week for three weeks resulted in high curative effects for already-diseased plants. Double spraying with fenarimol and the Mix 3 solutions 1-7 days before S. fuliginea inoculation resulted in the protective effects continuing for up to 20 days after spraying. When the disease reemerged at 20 days post inoculation, one reapplication of the spray suppressed the disease for another 7 days. Overall, fenarimol and Mix 3 were most effective for both the protection and suppression of the disease. These results implied that Mix 3 had fungicidal effects similar to fenarimol; therefore, the use of a Fenton solution such as Mix 3 may offer new possibilities for disease control.

The effect of sub lethal doses of six compounds, three acaricides (abamectin, ethion and chorfenapyr),one pyrethroid (cyhalothrin),one mineral oil (Nat-1) and one plant extract (Allium sativum)on some biological and behavioral characteristics of the two spotted spider mite,Tetranychus urticae and adult female of predators Stethorus gilvifrons, Amblyseius gossipi, and Phytoseiulus macropilis was examined. The results indicated that Cyhalothrin was the most effective compound tested on egg deposition, which is beneficial for some IPM programs away from predators' employments. A. sativum extract has the least effect on egg deposition that confers a chance to produce eggs enough for predation including egg mite, the preferable stage, for some predators. Ethion, chlorfenapyr and abamectin are considered ideal from the biological point of view since they decreased egg deposition to a suitable level and the character is needed for any integrated mite management program. Nat-1 is the best compound that has a moderate effect on egg deposition of spider mite which gave these compound special importance in integrated mite management. Nat-1 and A.sativum extract exhibited the least effective ovicidal action. The ovicidal effect of Chlorfenapyr and abamectin were about the same against the egg stage of spider mite. Cyhalothrin and ethion were highly toxic compounds that caused the highest decrease in egg hatchability. Cyhalothrin and abamectin were the most effective on prey egg consumption, predator egg production and predator's egg hatchability of three predators. Ethion and chlorfenapyr occupy the next position in prey egg consumption, predator egg deposition and predator's egg hatchability of three predators. Nat-1 and A. sativum extract were the least effective compound in prey egg consumption, predator egg deposition and predator's egg hatchability of three predators. Also, Nat-1 and A.sativum extract were the safest compounds that allowed the predator's egg to hatch producing the next stages necessary to the biological agent to minimize prey populations.

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