Verticillium Lecanii ——Control of greenhouse pests

The Verticillium Lecanii is a insecticidal fungus isolated from aphids and whiteflies with a wide host range, and can parasitize pests such as aphids, aphids, mites, whiteflies, and also can parasitize certain lepidopteran pests such as nematodes and thrips, etc. The Verticillium Lecanii is nontoxic and non contaminating to zoonoses. Temperature had a large effect on the growth rate, spore viability and spore production of Verticillium Lecanii, and the range of responses to temperature varied among strains from different geographic origins. Studies on the temperature of mycelial growth and spore production of Verticillium Lecanii in Taigu, Shanxi, China under different temperature and humidity and nutrient conditions revealed that the temperature range for mycelial growth and spore production was 12-35 ℃, and the suitable temperature was 20-32 ℃. The Verticillium Lecanii grew the fastest and produced the most spores on SMA medium. The conidia were able to germinate equally at 10-35 ℃, and the suitable temperature for germination was 25-32℃ at which temperature the 20 h spore germination rate could reach more than 96.61%.The Verticillium  Lecanii is an important entomopathogenic fungus of the genus hemiascomycetes, which hosts a wide range of insects and can parasitize mealworms, aphids, mites and mealworms, but also some pests of Lepidoptera and the nematode Thripidae. The Verticillium Lecanii can be infected in all insect states of protective mealworms, can become endemic in the whitefly population, and can survive in the greenhouse for some time when conditions of transmission are not suitable.

Moreover, the prevalence of Verticillium Lecanii is not very limited by the density of the whitefly population, it is not affected by the number of subcultures on artificial medium and so on, and the virulence is stable and not easily variable. Therefore, the bacterium is considered an important pathogenic microorganism in the control of whiteflies. The Verticillium Lecanii is also a parasite of plant fungal diseases. Such as can parasitize rust pathogens, cucumber powdery mildew, etc. The temperature conditions required for growth of the Verticillium Lecanii are wide in the presence of a water film or high humidity. Application of Verticillium Lecanii is mainly to control pests in the greenhouse, such as whiteflies, aphids, thrips, etc., while application of B. cerevisiae to control white mealworms of Tomato in the greenhouse is generally in the middle density of the insect mouth. And the technique of Verticillium Lecanii to control aphids with whiteflies was incorporated into the production system of theserum free vegetables in a protected site in northern China.

 

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Post time: Dec-06-2021