Epidemiology of Tomato yellow leaf curl virus in relation to intercropping and insecticidal spray effects on the Bemisia tabaci under field conditions.

摘要

Tomato yellow leaf curl virus (TYLCV) severely invaded tomato plantations in Egypt many seasons during recent years. This study aimed to discover the relationship between TYLCV and other epidemic-associated factors. The experiment, part of the present investigation, were conducted at the Plant Protection Research Station at Qaha, Kaliobia, Egypt during the fall seasons of 2007 and 2008 to deal with the effect of intercropping tomato with cucumber, squash and common bean on the behavior of the cotton whitefly B. tabaci (Genn.) and on spread of TYLCV in order to find out a practical approach to reduce or delay early infection. The relevant results for intercropping indicated that cucumber plants seemed to be the most preferable host to whitefly infestation as the highest number of adult stages. Consequently, the lowest percentage of TYLCV has been found on cucumber intercropping. The analysis of study results demonstrated that weekly treatment of Antivirus and Virox compounds had the lowest mean number of adult stages while Kemazed and Citrax compounds gave moderate level of control, on the other hand, the highest mean number of whitefly populations occurred in plots treated with Amicton, Atonic and Berelex compounds, over all dates, the lowest percentages of TYLCV incidence were observed in plots treated with Antivirus and Virox compounds. Kemazed, Citrax and Atonic compounds gave moderate effect on TYLCV incidence, while Berelex had no effect on disease infection. Population dynamic analysis of the whiteflies and monitoring of viruliferous whiteflies could be used for early prediction of TYLCV infection.