Gradient “3414” fertilizers and different irrigation amounts were applied in field experiments with drip fertilization conditions on rapeseed at Ershilipu town ,Xining city ,Qinghai province ,to investigate rules of water and fer-tilizer requirements for spring rapeseed cultivation by drip fertigation technology .The results showed that rapeseed yields reached 2 443 .5~3 132 .0 kg·hm-2 ,which was increased by 0 .8% ~29 .2% than those with the control treatment . N ,P ,and K fertilizer utilization rates were 50 .9% ,22 .5% , and 56 .7% respectively .Water utilization efficiency (WUE) reached over 4 .0 kg·hm-2·mm-1 ,which became increased by 42 .1% ~61 .4% compared with the control .It was further found that level of soil water content during growing period reached lowest at the bud stage ,followed by at the blossom stage ,and then at the pod stage .At the bud stage ,with the increase of soil depth in 0~60 cm layers ,the water content went up .At midterm and late stages ,water content became increased first then dropped .Minimal values of soil water content at 5 cm away from the dripper were lower than those 15 cm away .In conclusions ,the recommended fertiliz-er amounts for drip fertigation of rapeseed were N at 138 kg·hm-2 ,P2O5 at 61 .5 kg·hm-2 and K2O at 57 kg·hm-2 ,re-sulting in a yield potential of 3 000 kg·hm-2 .Minimal soil water contents that remained 55% (of soil saturated water content ) at the bud stage ,60% at the early blossom stage ,65% at the full blossom stage ,and 55% at the pod stage were suitable to get high water use efficiency in the experimental area .%在青海省西宁市北郊二十里铺镇，采用“3414”肥料设计和不同梯度灌水量进行大田滴灌春油菜需水需肥规律研究。结果表明，滴灌施肥条件下，春油菜产量达到2443．5～3132．0 kg·hm－2，各施肥处理比无施肥对照增产了0．8％～29．2％，氮、磷、钾肥的肥料利用效率达到50．9％、22．5％、56．7％。滴灌方式水分利用率达到4．0kg ·hm－2·mm－1以上，比大水漫灌提高了42．1％～61．4％。滴灌土壤含水量苗期＜盛花期＜角果期；0～60 cm土层土壤含水量苗期随着土层深度的增加而增加，中后期随着土层深度的增加先上升后下降。距滴头5cm土壤含水量最低值小于距滴头15 cm土壤含水量最低值。根据试验结果得出滴灌肥最大产量施肥量为N 138 kg · hm－2，P2 O561．5 kg·hm－2，K2O 57 kg·hm－2，最大产量可达3000 kg·hm－2。设置滴灌土壤含水量下限为苗期55％、始花期60％、盛花期65％和角果期55％的水分管理具有较好的水分高效利用效果。
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