Biology of ginger rhizome fly, Mimegralla sp. nr coeruleifrons (Diptera: Micropezidae)

Abstract

A survey conducted in the ginger growing areas of Thrissur and Palakkad districts of Kerala, during 2013 and 20 14, revealed the presence of three species of flies infesting both healthy as well as diseased ginger rhizomes. The predominant, most injurious one was identified as Mimegralla sp. nr coeruleifrons (Macquart) (Diptera: Micropezidae). The biology of the same was studied in the laboratory on diseased ginger rhizomes. The mean incubation period was 3.75 days, while the mean  duration of first, second and third larval instars was 2.25, 3.15 and 6.70 days respectively. The mean pupal period lasted for 8.80 days. The longevity of adult male and female flies was 43.90 and 51.00 days respectively, and the sex ratio was 1:1. The morphometric observations of each life stage are also described, with a note on the taxonomy of the fly.