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41.
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Mailing II rootstocks were grown throughout 1960 in sand on nutrient culture solutions containing 1, 4 or 10 mg. equivalents of nitrogen as nitrate (referred to as N4, N10 rootstocks) and during that summer each rootstock was budded with the variety Lord Lamboume. The growth, flowering and fruiting performance of the resultant maiden shoots were recorded from bud break 1961 to fruit set 1962. Throughout this second period each tree was given only a minimum of nitrogen (Nx) except during a certain period of one or two months’ duration, when it received a simulated fertilizer application (N10).

The greatest amount of primary extension growth in 1961 took place on the maidens given supplementary nitrogen in June on the N1 and N4 rootstocks and in July on the N10. Secondary extension growth in 1961 was apparently induced by supplementary nitrogen given to the maidens on the N4 stocks in July and to those on the Nx in August.

The highest number of fruit buds and blossoms in 1962 resulted from the June 1961 high-nitrogen supplement to the maidens on the Nr and N4 stocks and from the July supplement to the N10.

After open pollination, the maidens grown on the NIO stocks set fruit better than on those that were more nitrogen-deficient. Among the N10 and N+ maidens, those receiving the September nitrogen supplement gave the highest yield.

These results are discussed especially in relation to apparent differences in quantity and quality of blossoms. It is suggested that the quantity of blossoms is related to the amount of primary extension growth, while the quality is determined by the extent to which reserves of carbohydrate and nitrogen have been accumulated during the previous autumn.  相似文献   
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Water, Air, &; Soil Pollution - This paper presents a study of Pb contamination of soil at a clay target shooting facility in Canterbury, New Zealand. The spatial distribution of Pb...  相似文献   
44.
The proteins of wheat flour have several biological activities that can affect human health and physiology when wheat-based foods are consumed. The modifications of bread crumb and crust proteins during an in vitro peptic/pancreatic digestion process were studied by electrophoresis and immunoblotting with polyclonal antibodies specific for single proteins or groups of homologous proteins of the wheat flour, and the results were compared to those obtained for an unheated dough sample. The results show that baking affects the extent of proteolysis and the immunological and physicochemical features of the digestion products in relation to the level of the heat treatment. Therefore, the results concerning the digestion of the unheated wheat flour or dough are not representative of what happens when baked products enter the human digestive tract.  相似文献   
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Different inorganic ions were tested for their ability to replace nitrate as the terminal oxidant for bacterial respiration in anaerobic soils. Chlorate, bromate. selenate. tellurite and ferric ions were all unsuitable substitutes, lodate reduction in soils was similar to nitrate reduction because it required anaerobic conditions, was increased by glucose amendment and decreased by phenylmercuric acetate. Amendment of soils with iodate and measurement of iodide production can be used to measure nitrate reductase activity in a soil and so give a qualitative indication, and possibly a quantitative estimate, of the denitrification capacity of soils.  相似文献   
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