Studies on Bionomics and Control Methods of the Bulb Mite, Rhizoglyphus echinopus Fumouze et Robin

Abstract

In our country, the mites have been the most serious pests of the bulb production for export. In order to find the most efficient control methods, bionomics and insecticidal tests were studied. The results are as follows: 1) In the field, the mite has a tendency to propagate in hot and rainy seasons, but their population does not increase in other conditions. 2) Examining the living site of the mites in a lily bulb, most mites were found on the outside of bulb which were easily suffered from Fusarium sp. 3) As regard to the relation between outbreaks of the mites and occurrences of spot rot diseases, it seemes that the mite is not a primary pest, but a secondary one attacking the susceptible parts of the spot rot. 4) The dipping of bulbs into 45°C water solutiones of systemic insecticides or parathion for ninety minutes before storing or planting the bulbs was the most effective control methods. The cool solution was not so effective as the warm one. Even though the dipping hours increased, the mortality did not increase. 5) Methyl-bromide was the most effective insecticide for fumigation. 6) No phytotoxic effect on sprouting or developing of the bulbs was observed by dipping or fumigation. But thimet dust coating onto the bulbs retarded the sprouting seriously. 7) The spraying or soil injection of systemic insecticides against the growing lilies in the field was little effective. © 1962, JAPANESE SOCIETY OF APPLIED ENTOMOLOGY AND ZOOLOGY. All rights reserved.