Insect-proof Netting Technique: Effective Control of Bemisia tabaci and Tomato chlorosis virus (ToCV) in Protected Cultivations in China
Bemisia tabaci (Gennadius), the vector of Tomato chlorosis virus (ToCV), is one of the major pests of tomato (Solanum lycopersicum L. var. lycopersicum), potentially causing up to 100% yield loss. The purpose of this research was to effectively reduce intrusion by B. tabaci and control damage from ToCV in protected cultivations. The treatments included the use of a regular solar greenhouse as a control (CK); greenhouses I and II with 60- and 80-mesh insect-proof nets, respectively, that were installed in both houses at the front and upper ventilations; and greenhouse III with the addition of not only the 80-mesh insect-proof net as in greenhouse II but also a ventilating pipeline to the back wall. The effects of mesh size and back wall ventilation on the greenhouse temperature and humidity, number of B. tabaci, and level of ToCV infection were studied. Under all conditions tested (from 2014- 2016), the temperature of greenhouse III with installed netting was reduced by drilling holes through the back wall and nonsignificant difference existed in the average relative humidity between greenhouses II and III. Importantly, the number of B. tabaci and ToCV infection rate were effectively controlled in greenhouse III, ranging from 0.03 to 0.33 adults per sampled plant and from 0% to 6.67% of virus incidence. Thus, installing 80-mesh insect-proof netting at the front and upper ventilation areas as well as adding a ventilating pipeline to the back wall could effectively reduce the number of B. tabaci and prevent ToCV damage.