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Genetics, page 88) and sown in September in rod rows, replicated ten times. The results to date may be summarized as follows :— (1) In each case the field germinations of the treated seed were slightly lower than the controls. (2) Vernalized soy-beans were in flower three days earlier than the unvernalized. Vernalized maize was five days earlier than untreated. (3) According to height measurements there were no differences in vigour of growth. (4) In the case of maize, pollination was not completed until the end of February. In spite of treatment it appears doubtful whether the cobs will ripen. At that time also the pods of soy-beans were still green and immature. During the coming season vernalization trials will be continued with maize and soy-beans and garden vegetable plants. Gybotillek Cultivation and Crop-yields. During March, 1936, plots on three of the College fields were gyrotilled. These plots have been marked off so that crop-yields can be secured over a period of years, during which time the effect of gyrotilling can be compared with ordinary shallow cultivation. A yield of 61 bushels of Algerian oats was obtained from sample plots gyrotilled to a depth of 16 in., as compared with 56 bushels from those ploughed to a depth of 6 in. without gyrotilling. There appears, therefore, to be a difference of 5 bushels per acre in favour of gyrotiller cultivation, but the increase is not statistically significant. There was an interval of five weeks between gyrotilling and drilling, and this is considered sufficiently long to permit of consolidation and weathering. The cost of cultivation up to the time of drilling has been estimated as £1 6s. 6d. for the non-gyrotilled area, with an additional £2 10s. (1936) for the gyrotilled area. The increased yield of 5 bushels per acre is below the expectations of the contractor, but it is recognized that the effects of gyrotilling may extend over several years, and the results of this season's trials with the first crop must not be taken as the final result. Chop Diseases. Cereal Seed Pickling Trials. —During the past few'years wet pickling has been giving way to dry-dust treatments. In experiments at the College this year only dry dusts were used, and it was shown that the organic mercurial dusts, Ceresan and Agrosan, which are displacing copper carbonate, gave more reliable and steady increases than the latter in yield of smut-free lines of wheat and oats. That seeddisinfection of oats should be practised much more than it is at present is revealed by a questionnaire to 237 farmers, which showed that 67 per cent, treated their seed and 33 per cent, used untreated seed. Foot-rot of Wheat. —No serious attacks of foot-rot at the seedling stage were observed in wheat-fields in the Springs County. The highest infection was 5 per cent., compared with over 40 per cent, in past seasons. The present season has been a very favourable one for autumn-sown wheat, and growth has been rapid. Under such conditions foot-root is not a serious limiting factor ; only when crops are checked in growth by an adverse growing-season or by sowing too deeply or on a loosely consolidated seed-bed do the foot-rot fungi in the soil become serious parasites. Experiments on the effect of time of sowing and depth of sowing on foot-rot in wheat showed that, where there is heavy infestation with the disease, winter-sown crops are more severely affected than those sown in spring, and the deeper the seed the more predisposed is it to attack. Crop-disease Survey.—With a special grant made by the Department of Scientific and Industrial Research, a survey has been made of the distribution of certain crop-diseases. The area investigated embraces all counties from Cheviot and Amuri to North Otago. Five hundred and eighty crops of wheat, 245 crops of oats, thirty crops of barley, and various crops of rye-grass, cocksfoot, lucerne, and peas were examined. Information has been obtained on the occurrence and degrees of infection of stem rust, leaf rust, loose smut, covered smut, mildew, and take-all of the cereal crops. The results of the survey are being prepared as a special report. Entomology. The investigation of the insect and mite pests and vermin of grain-stores and flour-mills was concluded during the year. A report was submitted and recommendations made. A summary of the results of an ecological investigation of soil fauna was published. This investigation demonstrated that the lucerne flea (Sminthurus viridis) did not occur ip the areas worked, although a closely related species, which at times is regarded as almost as serious a pest in Australia, was present in Canterbury pastures. Biological control work on diamond-back moth has been extended to the South Island. A consignment of Angitia cerophaga parasites has been introduced into a glasshouse at Irwell, where large numbers of the host insects have been bred on cabbage and rape plants. It is expected that large numbers of parasites will be available next spring if they are successful in passing the winter in an unheated glasshouse under the climatic conditions prevailing in Canterbury. Field collections of diamond-back moth pupae and larvae were made in the vicinity of Lincoln with a view to gaining exact data on the degree of parasitism prevailing in the South Island due to the native insect Angitia lateralis. It is already evident that parasitism occurs to a considerably higher degree in the South than in the North Island. An investigation into the " wheat bug " problem of Otago was undertaken. A survey of the affected locality was carried out, and collections of sucking insects from wheatfields were made. Various bugs which were capable, of damaging wheat were experimented with on growing wheat at the College, and it was shown that three species: of bug, two being native to New Zealand and one cosmopolitan, attacked wheat. Baking-tests showed that the wheat-samples affected by the insects

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