|Title:||主要蔬菜作物之養分吸收及施肥效應(II)韭菜對不同型態氮肥之效應及所施氮肥之消長||Other Titles:||A Study on Nutrient Uptake and Fertilizer Response of Vegetables (II). Response of Chinese Leek to Different Source of Nitrogen Fertilizer||Authors:||連深
|Issue Date:||4-Sep-1977||Publisher:||農業試驗所||Journal Volume:||26||Journal Issue:||3||Start page/Pages:||195-203||Source:||中華農業研究||Abstract:||
2. 就各種氮肥之肥效而言，尿素顯然優於硫酸錏，而SCU （TVA製，含氮348％及384％者）則與尿素相當。本試驗中SCU分施僅7次，尿素和硫酸錏則多達25次。每次施肥均掘淺溝，施用後並需覆土，可見SCU節省施肥勞力之功效非常顯著。
To study the nutrient uptake of Chinese leek, a vegetable commonly fertilized with extraordinarily large amounts of nitrogen (1,000-2,000 kg/ha), while examining the relative eicffiencies of different sources of nitrogen including the slow—release type and the balance of nitrogen applied to the soil, a field experiment was conducted.
1. The nitrogen response of Chinese leek was so large that the leaf yield increased with the rate of nitrogen up to 1,500 kg/ha for the first year, however the optimum rate was about 800 kg/ha, if the applications were regulated according to the actual requirements of individual growth seasons. The optimum rates of nitrogen for various growth stages in the whole year were as follows:
2. As for the relative efficiencies of different source of nitrogen, urea was superior to ammonium sulfate. On the other hand, the effect of sulfur coated urea (made by TVA, U. S. A. N 34.8% and N 38.4%, respectively for the former three fourth of application and the remainder) applied in 7 splits corresponded to that of the urea applied in 25 splits, all the fertilizers were in corporated into surface soil on each split application, showing the labor saving effect of the former compared with the latter.
3. As a balance of the 1545 kg/ha nitrogen applied to the soil, it was estimated that only 14% of the nitrogen was absorbed by the crop, about 17 and 6% of the nitrogen remained respectively in the soil stratum of O-15cm and 15-30cm as nitrate and the remaining two third of the nitrogen was lost either by denitrification or by leaching with rain or irrigation water.
The loss of nitrogen, however, would have been minimized, if the applications were regulated according to the actual requirements of individual growing seasons, as shown previously.
|Appears in Collections:||1.台灣農業研究(1950～迄今)|
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