CROP PROTECTION THROUGH CONTROL OF PARASITES

Bay of Plenty Beacon, Volume 14, Issue 89, 23 January 1950, Page 7

CROP PROTECTION THROUGH CONTROL OF PARASITES

Parasitic insects are cultivated and many varieties are brought into New Zealand in order to destroy those insects that reduce our crop and pasture production. '•Our total,production of crops and pastures is selvipusly affected each year by insect pests, fungus, bacterial and virus diseases, and weeds. Many branches of the Department of Scientific and Industrial Research are engaged on research to combat these destroyers, and considerable progress in control has been made. One branch of the Department mainly concerned in research in relation to insects is the Entomological Research Station at Nelson, and working in close cooperation with this station uner a grant from the Department is a section of the Cawthron Institute. One important part of the research is the cultivation of those insects that feed on the noxious insects, but some of this work is at present only in the initial stages. Four native insect predators have been reared, and their effect on the grass grub is being studied; and cultures of the nematore parasite are being maintained on grubs in the soil until further developments in these investigations can be made. From Australia, eight * different kinds of parasites, totalling,., altogether 2,500, were successfully imported; all these are parasites of the Australian grass-grub. From America, bacterial “milky disease” has been brought and liberated for research work in an experimental area. In the laboratory at least three of . the Australian species of grassgrub parasite were found to „ attack the New Zealand grub, and one species has developed to be a parasite of the adult beetle. Under natural field conditions at Ashburton this species has also been successfully developed, and although observations have not yet been completed, the progress of this work has been very satisfactory. - - ■■■ -■■■