Management of Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) Using Biopesticides on Tomato Crop under Greenhouse Conditions

Tuta absoluta is the major insect invading tomato crop under greenhouse and open field conditions in Lebanon. Farmers mainly depend on chemical control to reduce damage caused by the larva. The hazard use of chemical agents can lead to resistance accumulation. The objective of this study is to investigate alternative agents like biopesticides to control this pest. Two field trials were conducted at the Lebanese Agricultural Research Institute (LARI) for two years under greenhouse conditions. In 2014, the first trial was conducted in two greenhouses- 1-control greenhouse without insect proof net (CG); 2-double door Greenhouse with insect proof net (DDG). In 2015, the second trial was conducted only in control greenhouse.Four treatments and control (not treated plot) were adopted in both trials. The biopesticides used in this study were Neem azal and Bacillus thuringiensis. Results of the first trial showed that using insect proof net reduced the captured adults on the water trap as compared with control greenhouse and thus reducing the damaged caused by the larva of tomato leaf miner on leaves and fruits. The adopted treatments have shown significant differences in the number of mines/leaf, live larva/leaf and percent of damaged fruits in both trials compared to the control. Applying Bacillius thuringiensis and neem azal separately and mixing them together have shown a promising alternative method to chemical control.