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(7) Potato-disease. (a) Virus Diseases. -These, most important diseases of potatoes in the Dominion, have been made the subject, of a special invest igation. Disease surveys of the potato areas have been made, to determine the extent of virus infection, and ascertain, if possible, areas free from this group of disease. Of all areas examined, Pukekohe alone shows comparative freedom from virus diseases. All types of virus have been studied in the field, and collections of typical material made. These have been planted at the farm, and have been under constant observation, with the result that we are now familiar with the field symptoms. Incidentally, all other diseases of the potato have been collected and are being studied on similar lines. Studies on pathogenicity are being conducted in the laboratory and glasshouse to determine certain points of the life-history, &c., with a view to working out methods of control. Commercial virus-free potatoes have been imported from Scotland, England, Ireland, and Canada, and grown under controlled conditions. Some of this material, especially Scottish seed, shows marked superiority to any lines grown commercially in New Zealand. Nucleus lines of completely virus-free tubers have been obtained from the Cambridge Virus Research Station during the past two years. Part of this material is being used in experimental work ; the remainder is being bulked under controlled conditions for ultimate distribution. In this way it is hoped gradually to eliminate virus diseases from the potato crops of the Dominion. (b) Corticium-disease.—Experiments on control of this disease have now reached a stage where we can obtain clean lines of seed. In the field, however, other factors, as soil-contamination, have made it difficult to apply this treatment on a commercial scale. It is believed that, in conjunction with the certification system now in use, more use will be made of this method for ridding crops of this disease. One point affecting the use of this treatment by the farmer was the possibility of damaging seed and thus reducing the yield. Experiments have shown that this is governed by time of treatment, for if tubers are treated some time prior to planting no damage results. (c) Jslack-leg, Mattery-eye, and Wilt. —Potato-disease surveys during the past three years have shown that considerable losses are experienced through a group of diseases commonly termed " wilts." Consequently, investigations covering these diseases are being conducted this season. For this purpose material has been collected and grown on the farm. Incidentally one disease previously unrecorded has been collected by Mr. Chamberlain, who records it as being prevalent in Pukekohe district. This is black-rot disease, due to the fungus Colletotrichum atramentarium, recorded abroad as being the cause of a stem-wilt. (8) Lucerne Nodule Organism. Inoculation of lucerne with the nitrogen-forming organism has proved such a success that during the season material sufficient to inoculate 18,000 lb. of lucerne-seed has been sent out of the laboratory. Studies were made of different manurial practices as they affected the organism, and in these it was found that superphosphate exercised a detrimental effect, whereas basic superphosphate or basic slag were without harm. In April the Mycologist left New Zealand for an extended tour through Canada, United States of America, Britain, and eight countries of the Continent of Europe. Studies of laboratory and glasshouse construction, laboratory technique, technique of seed-production, and the like, were made during this tour. On his return, in January, the laboratory has been undergoing a reorganization, modern methods being introduced wherever required. During his absence the laboratory work was carried on bv Mr. J. C. Neill. WHEAT RESEARCH INSTITUTE. Advisory Committee : Professor H. G. Denham (Chairman) ; Mr. C. H. Hewlett, Council of Scientific and Industrial Research; Mr. James Carr, Mr. W. W. Mulholland, and Mr. C. J. Talbot, representing the wheat-growers : Mr. R. K. Ireland, Mr. R. J. Lyon, and Mr. W. S. Pratt, representing the flour-millers; Mr. C. E. Boon, Mr. F. H. Hawker, and Mr. W. Montgomery, representing'the master bakers; Mr. J. W. Had field, Department of Agriculture; Mr. A. G. Cannons, Department of Industries and Commerce ; Mr. A. Jones, representing the grain and produce merchants. Director of Wheat Research Institute : Dr. F. W. Hilgendorf. Director's Report. The Institute was founded in February, 1928. It is financed by farmers, millers, and bakers' each of these paying lid. per ton of wheat or flour sold or bought. The levy is subsidized £1 for £1 by the Department of Scientific and Industrial Research. The Institute attempts to improve wheat, flour, and bread by research into the problems of wheat growing, milling, and baking. It has a chemical laboratory, an experimental flour-mill, and bakeroom in Ohristchurch in close association with Canterbury College, and a Plant-breeding Station on ground and in buildings supplied by Lincoln College. The activities of the Institute for the year were as follows : — (1) Wheat-breeding--(a) Variety trials were conducted at Lincoln, and at four other stations in Canterbury in conjunction with the Department of Agriculture. These were yield trials, with numerous replications of the plots to obtain reliable averages. In addition to them, the Department sowed in six localities single plots of several high-quality introduced wheats, to find what localities could grow these most successful ly. (b) Tn conjunction with the Department of Agriculture, the Institute carried on the w r ork of maintaining pure seed wheat, and certified crops as fit for seed. About 15,000 bushels of such seed were bought through the Institute and distributed by merchants last season.

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