CONTROL OF PESTS

Evening Post, Volume CXVIII, Issue 33, 8 August 1934, Page 17

CONTROL OF PESTS

RESEARCH IN FIJI

SUCCESS WITH PARASITES

I "The many recent successes oi' biological control of insect pests far outweigh any failures in the past," said Mr. T. McCarthy, senior assistant entomologist to the New South Wales Government, who is returning to Australia by the- Aorangi from a research expedition to Fiji," states the- •'Auckland Star." "In rocent years," said Mr. Me-! Cur thy, "great advances have been j made in the control of insect pests by I tho introduction of parasites. In Fiji j the- onoo deadly levuaua moth that at-! tacked tho coconut has been practically j ! stamped out by tho taehinid fly. The 1 clidemia weed has been controlled by the introduction of the thrips insect from Trinidad. This valuable insect prevents tho weed from fruiting and keeps it in a weakened state so that other plants can smother it. Another recent success has been the control of tho scale insect by a species of ladybird beetle. . Theso three successes alone outweigh any failures in the past." Mr. McCarthy said that in Australia the control of pests was largoly carried out by chemical spraying, but parasites had also been imported thero. A notable example was tho introduction of the small aphelimis wasp to check the woolly aphis pest. It was estimated that this tiny wasp was saving Australian fruit growers the sum of £30,000 annually in spraying alone. The prickly pear pest was being literally eaten out by tho cactoblastis moth. This enterprising little creature laid its eggs on the pear plant, and when the caterpillars hatched they ate their way into the heart of the stem and lived on the pith, so- that the plant just rotted away. Very great care was taken by tho Australian Government, said Mr. McCarthy, to test every uew importation. First a parasito was studied in its native country. If. it showed no dangerous habits thero it was brought to Australia and kept in an entomological quarantine station for some considerable time to watch for the development of any new characteristics that often developed in a changed eliinato. Only when the entomologists were absolutely sure it would do no harm was it released.

Mr. McCarthy has been some five weeks in Fiji carrying out research on a certain typo of parasito which it is hoped will be of benefit to Australian fruit growers. He is bringing with him a large specimen case full of queerlooking black beetles, like small Maori bugs. As ho has not yet reported to his Government, he was unwilling to discuss what particular Australian pest they are planned to destroy. They have one extraordinary characteristic, however, and that is feigning death. "When Mr. McCarthy carefully handled them they would curl up and appear quite lifeless'