黄筋泥棉田花铃肥施用技术研究

Studies on the application methods of nitrogen fertilizer for cotton flowering and bollforming in the quaternary red earth:

用１５Ｎ示踪法研究了黄筋泥棉田花铃肥的５种施用技术。两年试验结果表明，以１５Ｎ＋饼肥和１５Ｎ＋盖草两个处理表现较好。干旱期间耕层土壤含水量比对照增加６．８个和６．６个百分点。从８月１０日至１０月９日，１５Ｎ＋饼肥处理吸收的土壤氮比对照增加１７３．６２％，氮肥利用率为５３．４９％，干物质日增长量为４．８０３ｇ．株－１。１５Ｎ＋盖草处理依次为４３．５２％、３８．４４％和２．４１７％ｇ．株－１。而１５Ｎ＋盖膜和１５Ｎ＋浇水两个处理，在促进棉花早发方面效果较好，但中后期的效果不及上述两个处理。

It was studied with 15 N tracing techniques for the application methods of nitrogen fertilizer for cotton flowering and boll forming in the quaternary red earth in 1995 1996.During drought period,the soil moisture content in ploughed layer of the two treatments, 15 N+sod mulch and 15 N+colza cake,was 85.64% and 83 25% higher than that of the control,respectively.From Aug.10 to Oct.9,the absorbed nitrogen from soil was173.62% and 43.52% higher than that of the control,respectively.The utilization ratio of nitrogen and the daily increase of dry matter of cotton were 53 49%,and 4 803% g/plant for the 15 N+colza cake treatment,38 44% and 2 417 g/plant for the 15 N+sod mulch treatment,respectively.For the treatment of 15 N+plastic sheet covering and 15 N+water irrigation,the growth and development of cotton were significantly fast in the early period,and slower than that of the former,two treatments in the middle and later periods.