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A considerable amount of investigational work was carried out in the chemical laboratory in connection with the drying of wheat. With the rapid increase in the rate of harvesting during the past ten years there is a tendency for farmers to deliver wheat out of condition to the stores, with the result that the wheat is either rejected by the merchant or goes mouldy in the store. It was to combat this difficulty that the Institute's investigations were undertaken along three lines —namely, (a) testing the moisture content of wheat with a view to devising the best time for harvest, (b) advising the farmer how to dry his wheat after harvesting and before delivery, (c) devising a method of drying wheat which had been delivered to stores out of condition. The Chief Chemist during his recent visit to Europe investigated all systems of drying wheat in stores, and with the special knowledge obtained was able to devise a form of drier which could be cheaply and easily constructed from plant normally present in a Hour-mill store. The Institute's travelling baker has continued to give valuable service to bakers on a wide variety of baking problems, and has also been in charge of the school of baking, which is held in the Institute's laboratory for two months in each year. This school has proved very successful, most of those attending being of the grade of foreman or master baker. FRUIT RESEARCH. The opening of the new laboratories and experimental area of the Plant Diseases Division of the Plant Research Bureau at Auckland will enable fruit diseases to be studied more intensively and under much better conditions than hitherto. At the Research Orchard, Appleby, and the experimental orchards of the Cawthron Institute, fertilizer experiments have been continued. The 1938-39 season has been characterized by further significant increases in crop weights from certain manurial treatments, further evidence being obtained regarding the value of complete manures. Premature defoliation of fruit-trees has been occurring to an increasing extent on certain of the Cawthron Institute manurial blocks, particularly in the Jonathan variety, and the important discovery was made during the year by the Institute that this defoliation is due to a deficiency of magnesium and can be controlled by the injection of magnesium salts. In addition to its wide range of work on fruit diseases, the Plant Diseases Division has continued and expanded its certification scheme for sprays and other plant therapeutants. The success of this scheme may be measured by the numerous requests that have been received for the certification of other products. The Entomology Division has continued its studies of the insect pests of fruit, including the raspberry-bud moth, the raspberry saw-fly, and various diseases of citrus. Experimental work on boron in relation to physiological diseases has been directed towards the persistence of boron dressing in the soil. It appears that a soil dressing of J lb. borax per tree gives commercial control of internal cork for at least three seasons. Experiments by the Cawthron Institute in co-operation with the Department of Agriculture have shown that definite control of brown spotting of apricots can be obtained by the use of 0-1 per cent, borax spray or \ lb. borax applied as a* topdressing round the tree. Chemical analysis of the fruit confirmed boron deficiency as the primary cause of the ailment. Experiments on the preparation of unfermented apple-juice from six varieties of New Zealand apples have clearly indicated that a palatable and attractive juice can be prepared from some of these varieties, and that others which lack certain desirable qualities will nevertheless be of value for blending purposes. The tests are still proceeding, and certain sections of the work will be repeated for confirmatory purposes. Research on a number of fruit cold-storage problems has been continued. Further experiments with copper-treated wraps confirmed their value in controlling the spread of grey mould in Winter Cole pears. A small-scale experiment with pears demonstrated that it was desirable that every effort should be made to store pears as promptly as possible. Studies on the effect of fertilizer treatment on the keeping-quality in cold storage of various varieties of apples were continued during the 1938 season and a considerable amount of additional knowledge was obtained. Previous experimental work has shown that the use of top-dressings of more than | lb. of borax per tree had a detrimental effect on the keeping-quality of Jonathan apples. Experiments are being extended in the 1939 season to other varieties of apples, as it is probable that different varieties will react in a different way to a high boron content in the fruit. Gas storage trials with Ballarat and Washington apples were continued. The first season's tests indicated that a reduction in carbon-dioxide concentration was desirable, and as a result of the 1938 season's work it was found that Ballarats stored best in a temperature of 2-5 per cent, carbon dioxide and 18-5 per cent, oxygen at a temperature of 39° F., while it appears that the Washington variety can be stored for periods up to six months in an atmosphere containing 5 per cent, carbon dioxide and 16 per cent, oxygen at a temperature of 39° F. TOBACCO RESEARCH. Negotiations for the lease of approximately 18 acres of land at Umukuri (near Motueka) were completed in May, 1938, and the work of establishing the Tobacco Research Station was begun immediately. The research work of the Station is divided between the Tobacco Research Officer and the Cawthron Institute according to the facilities available. The Tobacco Research Officer has been fully occupied during the year in field experiments, which commenced with an extensive series of seed-bed trials designed to test various fertilizer treatments (including the addition of boron), the

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