Abstract
Malathion resistance was first detected in Sri Lankan Anopheles culicifacies in limited regions of the island in 1982. The frequency of resistance has been increasing slowly since then, but is not yet high enough to be considered an operational problem. Malathion toxicity is synergised in the resistant population by triphenyl phosphate, and metabolism studies suggest the involvement of a carboxylesterase enzyme. The spread of general esterase activity in individuals in an area of the island where resistance is present is wider than that in a totally malathion-susceptible area. However, the frequency of individuals with high esterase activity does not correlate well with resistance in the two field populations studied in detail. This suggests that a qualitative rather than a quantitative change in esterase activity may be involved in this resistance. Extrapolation from similar qualitatively changed carboxylesterases in other anophelines leads us to predict that the resistance in A. culicifacies will be malathion specific and inherited as a single semidominant characteristic.
| Original language | English |
|---|---|
| Pages (from-to) | 157-162 |
| Number of pages | 6 |
| Journal | Pesticide Biochemistry and Physiology |
| Volume | 29 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - 1 Oct 1987 |
| Externally published | Yes |