IN COLD STORAGE

Manawatu Standard, Volume LIII, Issue 313, 1 December 1933, Page 6

IN COLD STORAGE

HALF A MILLION INSECTS. FIGHTING WHITE BUTTERFLY. Nearly half a million parasites which are to attack the white butterfly this season are in cold storage in a refrigerator controlled by the Plant Research Station at Palmerston North, and another 80,000 are accommodated in its insectary. Arrangements are being made for their release as soon as possible, and during the next six months the activities of Mr J. Muggeridge, B.Sc., Government mycologist, will be centred on the work, together with a study of the biology and compilation of the life history of the butterfly. Subsequently it is hoped to extend operations and make a large collection of the diamond-back moth, another insect pest, in order to secure further information on their parasitic control with the object of later undertaking biological investigations in this field.

Mr Muggeridge returned to Palmerston North this week from a visit to Hawke’s Bay. He stated that there had been comparatively little appearance of the white butterfly due to the backwardness of the crops on -which they fed, and to the unfavourable weather conditions. There was as yet no ground for the suggestion that parasitic control was being exercised. This week some pupal parasites and about 2000 Apanteles glomeratis had been liberated at Maraekakaho. Pteromalis parasites would be arriving from England for distribution later in the season. Liberation of the parasites, added Mr Muggeridge, was being concentrated on Hawke’s Bay, because a start had already been made there, and conditions were favourable for the establishment of a good initial colony. Once that was established, there w'ould be ample parasites to populate the remainder of New Zealand. Isolated liberations dissipated the results. However, small distributions would be made in the Gisborne, Wairarapa and Manawatu districts as soon as the crops were full of young butterfly larvae. It was hoped also to start a small colony of the parasites in the South Island. PARASITE ESTABLISHED. KILLING TOMATO PEST. The first successful attempt to establish in the Southern Hemisphere a parasite which will attack the white tiy, a tomato pest, lias been carried out by.’ the Plant Research Station also under the supervision of Mr Muggeridge. The parasite used was imported from England and, known as Encasia formosa, is considered to have a tropical origin. In August of last year it was introduced at tlie Research Station’s insectary and kept there over the -winter by special methods of control. Liberations of the parasite have now been made at Whangarei, Auckland, Hastings and Christchurch, and some have been sent out to glass-houses in Palmerston North. Successful establishment of the parasite is already reported from Hastings.