H. —34,

Included in the consignment was butter made from cream neutralized to a low point; the reports on such butter indicated that it was not acceptable. The general results of these experiments is that care has to be taken, on the one hand, not to over-neutralize cream, and, on the other hand, to develop only a very low degree of acidity when starter is employed. In passing, it may be remarked that neutralizer-flavour reports are not always quite accurate. Whilst there are some cases in which the flavour is due to excessive neutralization of cream, we have had reported cases of neutralizer flavour in butter in which no neutralizer was used. Another interesting observation made in these experiments was that butter made from borderline finest-grade cream did not stand up to storage so well as did that made from absolutely finestgrade cream. The spreadability of butter is being given close attention. Dissemination or Results op Research Wobk. A course for dairy-factory managers, lasting for a week, was held at the Institute during the first week of May, when the technical results of experiments were explained to the managers. This contact with managers was invaluable, as it enabled research workers to explain in greater detail the nature and results of our work than was possible by means of published articles. A Monthly Bulletin which sets out matters of interest to dairy-factory managers is published by the Dairy Research Institute. It can be claimed that a very considerable amount of work has been accomplished, and that not only have some definite results been obtained, but also that many problems have been narrowed down most materially. Much remains yet to be done, and this can be carried out only by persistent effort and careful observation. The Institute has closely collaborated with the Dairy Division of the Department of Agriculture, the Massey Agricultural College, and the New Zealand Dairy-produce Board; to all of these bodies thanks are expressed for their hearty co-operation and assistance. The Institute has had the invaluable services of Mr. N. L. Wright, Scientific Liaison Officer of the Department of Scientific and Industrial Research, attached to the Office of the High Commissioner, London, who has made first-hand scientific inquiries and experiments in the United Kingdom on behalf of the Institute. PLANT RESEARCH. PLANT RESEARCH STATION. The Plant Research Station is conducted in co-operation with the Department of Agriculture, the work of the whole Station being directed by Mr. A. H. Cockayne. The reports set out below indicate those spheres of activity in which the Department of Scientific and Industrial Research is more particularly concerned. Mycological Section. I. Brassica Diseases. (a) Club-root (Plasmodiophora brassicae). —A considerable number of resistant strains of swedes, turnips, and rape, procured from Canada, Scotland, Denmark, and by selection at the Plant Research Station area, have been grown on heavily infected soil. From these, plants apparently immune to the disease were selected and seeded under controlled conditions. This seed has again been sown in infected soil for further immunity trials. Further work with field control of club-root by liming has been undertaken, attention being paid in this work to the effects of time of application upon control secured, even on heavily infected land, if 30 cwt. per acre of burnt lime is applied three months in advance of sowing the seed, and if seed is sown with 2 cwt. of basic slag or a 3 cwt. mixture of superphosphate plus hydrated lime. ('b) Dry-rot (Phoma lingam). —Many experiments conducted during the year have led to the production of a modified seed-disinfection method which it is hoped will give complete disinfection of lines infected with this disease. The process is a hot-water treatment, now modified so that seeds are immersed for fifty minutes in water held at 124° F. It would appear to be effective, since in the many hundreds of thousands of seeds tested (from a line averaging about 15 per cent, infection) no dry-rot fungus has appeared. Furthermore, those field areas sown with seed treated in this manner have remained free from infection. Seed of six varieties of swedes and turnips have been grown to maturity from seed treated by this method. The plants, which have remained disease-free throughout, have been seeded, and the seed, when tested, was likewise found to be clean. A portion of this seed is being utilized for bulking purposes, the remainder has been forwarded to certain British seedsmen who intend utilizing these clean nucleus lines for production of seed for this market. An improved method of testing seeds for the presence of dry-rot has been evolved, and has proved most useful against lines carrying out minute percentages of the disease. By this method, which is a modification of the cloche seed-germinator, from eight thousand to ten thousand seeds may be tested at one time. Certain British seedsmen have forwarded, from time to time, lines of swede and turnip seed which they claimed to have grown under conditions precluding dry-rot infection. Unfortunately, when tested under field conditions in New Zealand most of these lines have developed the disease.

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