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This demonstrates the necessity of using mixed nitrogen in the fertilizer to meet varying weather conditions. In a further experiment half the fertilizer was applied under the plant, while the remaining half was applied at intervals during December and January. It was found that delaying this second application later than mid-December resulted in a reduction of both yield and quality. Results of a spacing experiment confirmed those of previous seasons. With rows of a standard width, 3 ft. 6 in., a 2 ft. spacing of plants gave the best results both of yield and quality. On an area to demonstrate the effect on the plant of the absence of the chief plant-food constituents from the fertilizer mixture some striking results were obtained. Absence of nitrogen resulted in very low yield. Absence of potash did not affect the yield, but produced leaf of very poor quality. Leaving out the phosphate resulted in a very slow early growth, but apparently ample reserves in the soil finished off the crop quite well. The best yield and quality was obtained from the mixture containing low calcium. The results for the 1944-45 season will not be available until after the leaf is graded, but the following observations on the growth of the plots give some indication of the general trend. The continued heavy rain was responsible for leaching out much of the fertilizer, and in many instances differences were not very pronounced. The growth of the crop increased somewhat, but not outstandingly, as the quantity of fertilizer was increased up to 1,400 lb. Increasing the percentage of nitrogen resulted in a greater growth of leaf, but under the weather conditions prevailing did not delay maturity unduly. Extra potash resulted, in a smoother, better-bodied leaf. No apparent difference was noticeable from the use of different types of phosphate. There was a suggestion that tobacco after rye-corn was better than tobacco from the continuous toba,cco plots. In the placement of fertilizer once again the plots receiving the fertilizer in side bands were slow in coming away, indicating that at least some of the fertilizer must be within easy access of the roots. Where different forms of nitrogen were tried out the readily available forms appeared to stimulate early growth. Intake of Plant Nutrients Studies on the intake of plant nutrients by flue-cured tobacco have been continued. During the present season tobaccos grown on two soil types, a medium sand and a light phase silt loam, were studied. On both soils, plants of Harrison's Special variety grown in the seedling-beds at the Tobacco Research Station were used for the experiments. The object of the experiment was to ascertain at comparable dates the rate of growth of the plants on the two soils, and to determine for these dates the intake of nutrients by the crop. So far the yield data only are available. These show that on the medium sand of the Tobacco Research Station the maximum weight of dry matter was 1,614 lb. per acre at the sampling of 7th February —the plants on that date averaging 15-9 per cent, of dry matter. On the heavier soil the maximum figure for dry matter was 3,000 lb. per acre, obtained, however, later in the season. On the 7th February the dry-matter yield from the heavier soil was 1,852 lb. per acre, the plants averaging only 13-8 per cent, of dry matter. The higher content of dry matter in the tobacco grown on the sandy soil was noted at all stages of growth of the plants until maturity was reached. Magnesium Deficiency Finely ground dolomite and magnesite were again employed in three field trials on soils known to be low in magnesium content. Despite the rather wet season, typical symptoms of magnesium deficiency did not appear until late in the season, and then only on one of the experimental areas to any marked extent. The use of dolomite or magnesite improved the texture of the leaf on the area most affected by magnesium deficiency. Chemical Composition of Tobacco with different Fertilizer Treatment Mineral analysis of tobacco samples from the fertilizer trials at the Tobacco Research Station during the 1942-43 and 1943-44 seasons have been completed. The results show that omission of potash and nitrogen from the fertilizers leads to reduced amounts of these plant-foods in the cured leaf on the sandy soil of the Research Station. When the nitrogen content of the fertilizer was increased, the content of nitrogen in the cured leaf did not always rise consistently. Although the use of potash in fertilizers was reflected, in general, by an increased content of this constituent in the cured leaf, there was a limit beyond which increase of potash in the fertilizer resulted in little further increase of potash in the leaf. Wide spacing of tobacco plants in the field tended to increase the nitrogen content of the cured leaf without affecting significantly the content of mineral constituents. Much time has been devoted to estimations of reducing sugars and sucrose in the tobacco samples obtained from the Research Station. In the 1943-44 season the sugar contents were higher than those for the previous seasons. It would appear that seasonal conditions during the growing and harvesting of the tobacco exert an important influence on the sugar contents of the cured leaf. An interesting feature of the analyses of tobacco samples obtained from Tapawcra was the high content of magnesia in the samples. In one sample the magnesia content attained the high figure of 4-5 per cent. MgO on the dry matter. The high magnesia figures of the Tapawcra samples were associated with reduced contents of lime and potash. Seed-bed Experiments These experiments were designed to serve two purposes : to study the effect of various soil treatments and seed-bed practices on the incidence of mosaic in the field, and to provide information on the value of various bed treatments on the raising of seedlings. Steam-sterilized soil proved superior to unsteamed, the plants from the steamed soil not only being larger and more forward, but also having a relatively larger root system. As regards fertilizer, Jib. tobacco fertilizer per square yard proved the best for steamed soil, while on the unsteamed the optimum appeared to lie between J lb. and 1 lb. Various chemicals were tried as soil disinfectants, but too short a time was allowed to elapse between treatment and sowing, and all chemicals showed a retarding effect on growth. The standard fertilizer containing 3 per cent, nitrogen proved superior for the raising of plants to mixtures containing more or less nitrogen. Increasing the percentage of nitrogen resulted in a decrease in the proportion of root weight to leaf weight.

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