Repellent efficacy of plant extracts against Bemisia tabaci B- biotype( Homiptera: Aleyrodidae)

Whitefly( Bemisia tabaci) is an important pest of many field and greenhouse crops. In addition to causing damage by feeding on plant sap,it has mixed diet,widely host and also spreads the virus and plant physiological abnormalities. This experiment focused on the repellent effects of six species of plant essential oils and four kinds of water extracts of plants on B biotype whitefly adults using the Y-olfactometer. The results showed that: at 5 μL dose,6 oil repellency index( RI) is: Hawthorn( 60. 09)> pepper( 48. 53) > Chinese medicine( 2. 83) > Plantain(- 30. 01) > Basil(- 36. 13) >Houttuynia(- 47. 07); At the α = 0. 05 level,except the Chinese medicine,other treatments were significantly different from the control. Hawthorn equal mixture of oil and pepper repellent index was45. 00; at 5 g / L dose,four plants extract water repellent index( RI) is: octagonal( 41. 28) > garlic( 39. 37) > Citrus( 39. 09) > pepper( 35. 45).