INTEGRATED CONTROL USING DIFFERENT METHODS AGAINST TWO LAND SNAIL SPECIES Theba pisana ( Muller) AND Helicella vestalis ( Pfeiffer) INFESTING Citrus nobilis TREES AT SHARKIA GOVERNORATE

Abstract

Number of field experiments were conducted to evaluate the efficiency of certain safe and non-safe control methods as components of integrated pest management which help in reducing the population density of two land snail species, Theba pisana and Helicella vestalis infesting mandarin (Citrus nobilis) trees in orchards at newly salhyia, Sharkia Governorate during 2010-2011. The safe methods were agricultural control (Tillage or plowing process and plant traps) and mechanical control (hand picking) for six weeks. The non-safe methods were chemical control by some toxicants (glyphosate: Herbicide, carbofuran: Insecticide and nematicide, chlorpyrifos-methyl: Insecticide, methamidophos: Insecticide, paraquate: Herbicide) and biological control by Xentari : Bacillus thuringiensis (B .T.) : Biocide and Insecticide.These toxicants were prepared as wheat bran baits for three weeks. The tested IPM components reduced the snail population of both species depending on their efficiency and the time of performance. Tillage, plant traps, toxicants and hand picking revealed that glyphosate was the most effective toxicant giving highest average values of reduction percentage (58.02% and 61.4%) followed by tillage process (53% and 45.5%), plant traps (44.7% and 52.7%) and hand picking (37.9% and 45.2%) for Theba pisana and Helicella vestalis respectively, at the end of experiments. The biocide xentari (Bacillus thuringiensis) was the least effective one (31.9% and 32.02%). Moreover, the descending order of the tested toxicants was, glyphosate, carbofuran, chlorpyrifos-methyl, methamidophos, paraquate and Xentari.