Erosomyia mangiferae (mango gall midge)

Infested mango buds, shoots and young fruits bear many small blister galls, about 3-4 mm long, each containing a yellow E. mangiferae larva. In severe attacks the affected plant parts shrivel and die. Small emergence holes may be detected where larvae have left the galls to go to the soil and at this stage secondary fungal infections may develop. When young fruits are attacked, the exit holes are usually on the lower side of the fruit near its point of attachment to the axis of the inflorescence.

Cultural ControlIn India, Prasad (1971) noted that the standard practice of flooding the root zone of mango trees before flowering inhibits the emergence of E. mangiferae adults from the soil.Biological ControlBiological control has not been attempted and would require considerable research on the natural enemy complex, especially in India where it is likely to be most diverse. Grover (1986) surveyed indigenous parasitoids of E. mangiferae and other cecidomyiid pests of mango in India and suggested that there may be a good biological control agent among them. Host-plant ResistanceApparent differences in varietal susceptibility have been reported in India but long-term breeding for resistance or tolerance does not appear to have been attempted.Chemical ControlIn India, chemical control has been attempted using contact insecticides to kill emerging adults. Timing of applications is critical but some success has been claimed in small-scale trials (Prasad, 1971). Soil treatments have also been used to kill carry-over populations of larvae in soil under mango trees. Pheromonal ControlAlthough observations in India clearly indicate that males are attracted to virgin females, no work has been done on the pheromones involved.Integrated Pest ManagementGrover (1986) reported integrated control of pests of mango in India, but formulation of effective IPM programmes will require further research.

In India, E. mangiferae is considered to be a serious pest of mangoes, having a greater impact on fruit yield than other species of cecidomyiid attacking this host plant (Prasad and Grover, 1976). Buds, young shoots, inflorescences and young fruit are damaged directly by larval feeding, and losses of more than 70% of the potential fruit yield of individual trees have been reported. Symptoms of E. mangiferae attack resemble those produced by fungal infection, especially anthracnose disease, and it is therefore possible that the importance of midge attack may not be recognized by untrained observers. Serious outbreaks have been recorded throughout India, from Cape Comorin in the south to Amritsar in the north (Prasad, 1971).Waterhouse (1993) recorded E. mangiferae as a locally important pest of mango in Thailand.