Results Obtained in the Biological Control of Western Corn Root Worm

To establish a pest control strategies in a agroecosistem, the first requirement it’s the correct diagnosis and identification. In the literature there is much information about the chemical control of the species Diabrotica virgifera virgifera Le Conte. In biological control, which is the subject of the present article, we used the bioproduct “BIOBIT” based on Bacillus thuringiensis either as seed treatment or treatments on the vegetation. In the experimental period, the larvae attack symptoms were manifested by the appearance of "goose neck", in control plot, the attack frequency being about 33.36% in 2007, 15.46% in 2008 and 25.33% in 2009. Biobit bioproduct applied only to the seed reduced the incidence of attack to 6.92% in 2007 (79.2% less compared to the control) to 5.76% in 2008 (about 71% less compared to the control) and 5.76% in 2009. The degree of adult’s attack on leaves in the control plot, was about 17.17% in 2007, 19.83% in 2008 and 17.97% in 2009. The best results were obtained with Biobit products applied to the seed and on vegetation, the degree of attack being about 9.15% in 2007 (46.7% efficacy), 9.14% in 2008 (53.9% efficacy) and 9.08% in 2009 (49.5% efficacy).