水稻流入施肥法及流入肥料效果研究

进行了流入施肥法可行性，流入肥肥效及替代进口肥料试验。结果表明：流入施肥法与人工撒施，均能使肥料在田间分布均匀，流入施肥法比人工撒施增产3．4％，流入施肥法是可行的，日本流入肥和国产复合肥流入施肥田间3－4d后，在田间分布都较均匀，水稻追施分蘖肥和穗肥时水的温度都在30℃左右，两种肥料的溶解度比较大，易配成溶液，适合作流以施用，日本流入肥和中国复合肥对水稻的增产效果相差不大，可用国产复合肥料替代进口肥料；吸附试验表明，施肥5d后，流入肥料和其它氮素肥料中氮素的吸附率达82．5％－89．3％，流入施肥后5d内不要排水。流入施肥法适合土地平整，田块较大，灌溉条件好，人多地少或农业人口老龄化和血吸虫疫区等平原湖区稻田。

EFFECTS OF INFLOW APPLICATION METHOD AND INFLOW FERTILIZER IN PADDY FIELD

The experiments of top dressings for re-greening and heading were carried out in 1999 to compare the effects of dressing inflow fertilizer S550 by inflow method and spreading method (CK). The results show that there are no significant differences between inflow method and spreading method in both EC values and nutrient concentrations of field surface water in 2-3d after top dressing. Although both fertilizer application methods could lead to even distribution of fertilizers in rice fields, the inflow application method brought a certain effect on yield increase (3.4 % increase in actual yield compared to CK). The inflow application method is practicable in Jianghan Plain. The inflow fertilizer (S550) made in Japan and the compound fertilizer made in China were used as top dressing at tillering and heading stages by inflow method in year 2000. The results of the test were that there was no significant difference between the two fertilizers in both EC value in surface water of paddy field in 3-4days after top dressing, and the distribution in the field were better uniformity. The difference in the increase yield between S550 and compound fertilizer was little, so it was possible to use compound fertilizer made in China instead of imported inflow fertilizer. In addition, the result of soil adsorption test in laboratory indicates that the rates of N in the fertilizers adsorbed by soil in 5 d after dressing range from 85.2 % to 89.8 %, therefore no drainage should be done within 5 d after dressing.