Biology of rhizome fly,Mimegralla coeruleifrons Macquart (Micropezidae: Diptera) in India,a pest of turmeric and ginger crops

Abstract

The observations were made on the life history of rhizome fly, Mimegralla coeruleifrons Macquart on turmeric and ginger plants. A female laid from 76 to 150 eggs in the soil under laboratory conditions. The incubation period varied from 2 to 5 days. Three larval instars were observed. The durations of first, second and third instars were 4 to 7, 4 to 8 and 3 to 10 days, respectively. The total larval period ranged from 13 to 25 days. The pupal period lasted for 5 to 15 days, adults from 7 to 24 days, and the total life span from 38 to 62 days. The sex ratio was 1: 1 approximately. The stages are described. A parasite, Trichopria sp was recorded from its pupae. The pupal stage appeared to be responsible for carry over of the pest in planting seed rhizomes from season to another. The peak period of infestation in endemic areas was from mid August to mid October.