THE DIAMOND-BLACK MOTH

Timaru Herald, Volume CXLII, Issue 20587, 28 November 1936, Page 15 (Supplement)

THE DIAMOND-BLACK MOTH

THE “ANGITIA” PARASITE SUPPLIES TO BE LIBERATED IN HAWKE’S BAY The damage by the diamond-back moth Upon turnip and rape crops is of such a serious nature that the news of the introduction of a parasite to combat the pest will be welcomed by all farmers The parasite is known as the “angitia” and the first supplies are to be liberated in Hawke’s Bay in the near future.

The W'ork of acclimatising the parasite and of multiplying the specimens available is at present in progress at the Plant Research Station, Palmerston North, and will later be extended tn Canterbury. They were imported from Farnham House, England, which is the head of the entomological station of the Imperial Bureau of Etomology, located in Buckinghamshire, and is engaged in providing an entomological service for the whole of the Empire. On the strength of the effectiveness of the angitia in England and Europe, shipments were made to New Zealand. The importation of these was easier than was anticipated, but that does not necessarily mean, of course, that they are going to be readily adaptable to all conditions in this country. That remains to be seen, but strong hope is held out for the success of the venture.

Those parasites which have been introduced so far have been successfully acclimatised by Mr J. Muggeridge at the Entomological Division of the Plant Research Bureau, Palmerston North, and at the present time the work of multiplying and trying these out on the diamond-back moth is in progress. It is hoped this year to have sufficient “angitia” available to enable a limited number of field tests to be carried out. Under the control conditions at Palmerston North “angitia” apears to be a very active parasite, which lays its eggs in the bodies of the diamondback moth grubs found in the leaves of cabbages, rape and turnips. While further shipments are being awaited a search for other parasites is still proceeding overseas. It is not anticipated that any adequate supplies for general liberation will be available till next season.

In dry seasons the diamond-back moth makes very strong inroads into returns from cruciferous crops in the Dominion, and in some years the ravages have been so serious as almost completely to destroy turnip and rape crops, causing considerable embarrasment to farmers who depend largely on the use of these two crops in fattening their lambs. At present there is no economic method of controlling the moth in the field crops of the country, and the recent introduction of parasites therefore, if successful, will prove of great economical importance to farmers.