湖北省油菜施肥现状调查

对湖北省20个油菜主产县（市）的356个农户2007/2008年度油菜施肥状况进行了调查。结果显示,所有种植油菜的田块均施用了化肥;施用有机肥的比例仅为19.8%。全省油菜氮（N）、磷（P2O5）和钾（K2O）肥平均施用量分别为171.9、61.7和50.3kg.hm-2,N∶P2O5∶K2O的比例为1∶0.36∶0.29,其中化肥提供的N、P2O5和K2O分别占总投肥量的96.1%、92.1%和80.3%。施肥量分级结果表明,农户普遍重视氮肥的施用,施氮（N）量〉120 kg.hm-2的田块比例为64.3%;磷、钾肥施用不足,施磷（P2O5）、钾（K2O）量〈45kg.hm-2的比例分别为35.4%和48.9%。油菜施肥次数以两次（基肥＋1次追肥）的比例最高,占56.0%;78.3%的氮肥用作基肥施用。调查结果表明,湖北省油菜种植中的施肥问题主要有：（1）养分不平衡,磷、钾肥用量偏低,尤其钾肥用量明显不足;（2）有机肥施用比例、施用量偏低,秸秆还田率低;（3）氮肥用量不足及过量的现象均有存在;（4）施肥次数与油菜生长及养分吸收规律不匹配,前期氮肥用量比例过高。

Investigation of present fertilization on rapeseed in Hubei province

An investigation of nutrients management on rapeseed in 2007 and 2008 was carried out in Hubei province.It covered 356 rapeseed farmers distributed in 20 counties from main product area.The survey indicated that chemical fertilizers were applied in all farmlands,only 19.8% farmers used organic fertilizer.The average applications of N,P2O5 and K2O fertilizer were 171.9,61.7 and 50.3kg·hm-2,respectively with the ration of 1∶0.36∶0.29.The chemical resource of N,P2O5 and K2O accounted for 96.1%,92.1% and 80.3% respectively in the applications.Farmers paid more attention to N fertilizer application.There were 64.3% lands fertilized over 120kg·hm-2 nitrogen.And phosphorus（P） and potassium（K） fertilizer applications were much lower than N application.The proportions of P2O5 and K2O application（below 45kg·hm-2） were 35.4% and 48.9%,respectively.As for the times of fertilizer application,there were 56.0% rapeseed applied twice（base application and one-time topdressing）,of which the nitrogen proportion as base fertilizer was 78.3%.The nutrient problems in Hubei rapeseed were as follow：unbalanced N∶P∶K ratio and low P/K application,especially low K;less organic fertilizer and low straw returning rate;excessive or insufficient N nutrition in various situations;inefficiency of fertilizer applications,such as timing and excessive N as base fertilizer.