Abstract: 【Aim】 Grape phylloxera (Daktulosphaira vitifoliae) has been found in some vineyards in China and caused serious damage. Our previous research found that aqueous extracts of tobacco could control the damage of D. vitifoliae on excised roots. The aim of this research was to evaluate the control efficacy of aqueous extracts of tobacco towards grape phylloxera infection and grape growth. 【Methods】 Two year-old Kyoho grapes were chosen as the test materials in the greenhouse, and the root activity, overground growth amount, number of nodosities and photosynthesis rate of the grape were determined. 【Results】 The results showed that aqueous extracts of tobacco had certain alleviating effects on phylloxera infection. Both the aqueous extracts of tobacco at the concentration of 20 mg/mL and 50 mg/mL had an inhibition to phylloxera infection. At 21 d after the aqueous extracts of tobacco were applied, the number of nodosities of the grape in the treatments with 20 mg/mL and 50 mg/mL aqueous extracts of tobacco decreased by 42.9% and 52.8% as compared with that of the phylloxera infected grapes (the infection control). Compared to the infection control, plant growth amount in the treatments with 20 mg/mL and 50 mg/mL aqueous extracts of tobacco increased by 57.1% and 7.7%, respectively. Grape phylloxera infection decreased the microorganism amount in the soil; however, the aqueous extracts of tobacco decreased the amount of fungi, which could decrease the secondary infection possibility of microorganisms. 【Conclusion】 Aqueous extracts of tobacco have a control effect on grape phylloxera and can ease the damages caused by phylloxera infection in potted tests.

Key words: Grape phylloxera, grape, tobacco, aqueous extracts, control effect, plant growth, photosynthesis rate, chlorophyll fluorescence