PROPOSED MEASURES OF CONTROL MANAGEMENT OF THE GRAPE MOTH, LOBESIA BOTRANA DEN AND SCHIFF (LEPIDOPTERA: TORTRICIDAE),...

This study aims to evaluate the efficacy of five measures; including the release of two strains of Trichogramma, Bacillus thuringiensis (B.t.). Sweetened B.t. and the environmentally friend insecticide (Tracer®), to manage the grape moth, Lobesia botrana that infested the grape vines c.v. "Thompson seedless " in Egypt severely during the two successive years of 2011 and 2012. In concern to the release of the worldwide, Trichogramma evanescens Westwood., the mean total grape yield ranged from 8.00 to 14.00 ton/fed and from 6.90 to 11.9, in respect to the two seasons and the mean infestation percentages fluctuated between 50.00 and 16.14; 43.48 and 21.01 in sequence for the same years. The corresponding grape bunches loss percentages averaged from 21.43 to 6.91; 18.63 to 9.00,respectively for the same periods of this study. Whereas, it was noticed that in releasing the indigenous T. bourarchae was more effective than T. evanescens in reducing all the above mentioned grape yield particularly. Applying Bacillus thuringiensis (B.t.) and/or adding sugar as a stimulant to improve yields reduced the infestation and the crop loss percentage. However, Bacillus thuringiensis mixed with sugar which overweighed the use of Bacillus thuringiensis alone. Although Tracer® provided good harvest in both years, but unfortunately it affected the grape berries components rather than the other treatments. Control plots indicated 48 and 50% infestation, with very low yield compared with the other five trials to manage the assigned insect pest. For the first time worldwide economics and profits were computed taking into account the whole market sale, the total control costs and the gross income to decide the most profitable treatment for the table grape growers under the Egyptian conditions. It was found that the mean (L.E.) profits/fed were arranged in a descending order as follows: 470.95, 513.28, 504.78, 500.82, 397.25 and 0.00 for Bacillus thuringiensis + sugar, Trichogramma bourarchae, Trichogramma evanescens Westwood, Dipel-2x®, Tracer® and control in respect in 2011. The corresponding values in the year 2012 were 453.85, 445.58, 427.18, 377.00, 349.18 and 0.00 for Trichogramma bourarchae, Bacillus thuringiensis + sugar, Dipel-2x®, Trichogramma evanescens Westwood, Tracer® and control in respect. The obtained results were analysed and discussed in the text.