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The systematica and distribution of the grass-grubs and beetles have been seriously studied for the first time and important data secured as to the different species, together with important information on host-plant relationships. In regard to natural controlling factors, work has commenced on the possibilities of a bacterial disease and of a parasitic nematode worm against the common grass-grub. Insect parasites that are required do not occur in New Zealand, but arc well represented in Australia, where a special research is to be undertaken to secure species which will be of use in solving the grass-grub problem. Diamond-back Moth This moth, which has been a pest on cruciferous crops (approximately 600,000 acres of these crops are grown by farmers annually) such as rape, turnips, swedes, and chou moellier, over the last sixty years or more, and over which period thousands of pounds of destruction to these crops has resulted, is now showing signs of being well controlled by parasites. In the last annual report it was mentioned that the degree of control attained in the North Island " reached a high peak of efficiency," while in the South Island the report states " the same degree of success has not been reached as in the North." A field survey and inspection of crops during the present season has just been completed. The areas covered in the North Island include Wellington, Manawatu, Wanganui, Taranaki, Hawke's Bay, and the Wairarapa, and in the South Island include Nelson, Marlborough, North and South Canterbury, and Northern Otago, and it is very pleasing to report that the position this year in the North Island is even better than it was last year, while the position of the crops in the South Island is such that the control of the moth here and the condition of the crops generally is at least equal to the control being obtained in the North Island. In so far as market or vegetable gardens are concerned, none has been examined, for the reason that practically all these gardens are sprayed heavily ; the spray recommended is probably just as toxic to the parasites as it is to the moth caterpillar. It should be pointed out, however, that cabbages in particular appear to suffer more from attacks by the diamond-back moth than most other crops, so what degree of control might be obtained in the absence of sprays would hardly be sufficient perhaps to check injury, so that no economic loss would result. The method of estimating the degree of prevalence of the moth is based on the number of moth pupse collected for a given period of time—for example, ten minutes—and also on the condition of the crop. When this work first commenced it was a very simple matter to collect hundreds of diamond-back moth pupse over a very short period of time. Collection on crops during 1939 and 1940, for example, frequently yielded anything from fifty to one hundred diamond-back moth pupre per ten minutes of collecting ; it would take hours of collecting during the present season to get anything like the same number of pupa;, and in no case after inspection of hundreds of crops has any crop shown signs of being seriously damaged by diamond-back moth. How far the present condition is duo to season, such as consistent rainfall, high humidity, and phenomenal crop growth, one is unable to say, but it is clear that the parasites are playing a very major role and are responsible for the high degree of control which it has been found exists during the present season. White Butterfly The present season has been one in which white butterfly has been able to cause quite a lot of damage to cruciferous crops. The wet conditions under which the butterfly seems to be able to multiply have been widespread. In order to improve the control of white butterfly by parasite means, some work on collecting and distributing larval parasites has been carried out. The larval parasites have been established in Nelson for some time, and it has not been possible to distribute them farther afield because of lack of staff to undertake all work which occurs at this period of the year. During the present season, however, some larval parasites have been distributed in Ashburton and in Hawke's Bay, as once they are established in these localities they should spread fairly readily over the rest of the cruciferous-growing areas. Case-bearing Clover-moth (Coleophora Spissicornis) This moth appears to be increasing in the Hawke's Bay area and is apparently causing a good deal of loss of white-clover seed. Unfortunately we do not know of any suitable methods of controlling it at the present, and there is little that can be done about it until the matter is fully investigated. GRASSLANDS DIVISION Director : Mr. E. Beuce Levy The past year has been a remarkable one for growth, but the persistent wet summer has made cultivation and general upkeep difficult. A very full programme has been maintained and the work continues to expand. The entire lack of any suitable building is more and more adding to the difficulties of staff and administration. Plant-breeding A primary function of the Grasslands Division is the breeding of improved strains of pasture species. The majority of our pasture species are characterized by extremely wide variation between strains and between the constituent plants of any one strain. Over the last decade strains of a number of our most important pasture species have been bred at the Grasslands Division and have proved superior in the field to the strains previously available to the farmer. There are still many directions in which further improvement is desirable, and gradual improvement by breeding is being applied to existing bred strains. Further than this, however, entirely new strains are being bred by hybridization between strains or even between species. Although the shortage of staff is still acute, the breeding programme during the year has been maintained as far as possible. The main species under study are perennial rye-grass, Italian rye-grass, short-rotation or HI rye-grass, Western Wolths rye-grass, cocksfoot, timothy, white clover, and red clover. Of these species, bred lines of perennial rye-grass, Italian rye-grass, HI rye-grass, white clover, Montgomery red clover, and broad red clover are now on the market as Government certified strains. Of the remaining species, pedigree strains have not yet been produced for distribution.

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