包膜控释尿素（追施）对冬小麦生长发育及土壤硝态氮含量的影响

通过田间试验,研究了苗期和返青期追施释放期为30d和60d的包膜控释尿素对冬小麦生长发育及土壤硝态氮含量的影响。结果表明,分别在冬小麦苗期和返青期追施释放期为60d包膜控释尿素（N60N60）,能显著促进植株生长发育,增强植株对N、P、K养分吸收,增加籽粒产量。与不追肥（CK）处理相比,N60N60处理植株地上部和地下部干物重分别提高33.21%和67.84%;叶片叶绿素含量增加12.77%～25.20%;植株茎叶N、P、K含量分别增加63.55%、37.08%和6.91%,籽粒N、P、K含量分别增加8.56%、31.18%和24.49%;小麦穗长、穗粒重、千粒重和籽粒产量分别增加14.14%、27.00%、39.32%和48.01%。在返青期追施1次包膜控释尿素,N0N30优于N0N60处理,叶绿素含量增加1.50%～3.04%;植株茎叶N、P、K含量分别增加12.37%、12.25%和1.26%,籽粒N、P、K含量分别增加0.50%、5.69%和9.74%;小麦穗长、穗粒重、千粒重和籽粒产量分别增加2.84%、11.81%、11.65%和6.61%。同时,包膜控释尿素施用能明显减少硝态氮向土壤深层渗漏数量,减轻对地下水污染风险。

Influences of Topdressing Controlled-Release Coated Urea on Plant Growth and Soil NO 3-N Content of Winter Wheat

A field experiment was performed to study the effects of controlled-release coated urea with duration of 30 d and 60 d topdressed at seedling stage or regreening stage on plant growth and soil NO3-N content of winter wheat. The results showed that controlled-release coated urea （with duration of 60 d） could significantly promote plant growth, enhance N, P and K absorption, increase grain yield when it was top- dressed at seedling stage and regreening stage. Compared with CK （only basal fertilizer was applied） treatment, the dry weight of shoot and root was increased by 33.21% and 67.84% respectively, the chlorophyl content in wheat leaves was increased by 12.77%-25.20%, the N, P and K content in shoot and grain were increased by 63.55%, 37.08%, 6.91% and 8.56%, 31.18%, 24.49% respectively. The spike length, grain weight, 1000-grain weight and grain yield were higher of 14.14%, 27.00%, 39.32% and 48.01% than the control treatment（CK）. Controlled-release coated urea topdressed once at the regreening stage, NON30 treatment was better than NON60 treatment. The chlorophyl content was increased by 1.50%~3.04%, the N, P and K content in shoot and grain were increased by 12.37%, 12.25%, 1.26% and 0.50%, 5.69%, 9.74% respectively. The spike length, grain weight, 1000-grain weight and grain yield were increased by 2.84%, 11.81%, 11.65% and 6.61%. At the same time, controlled-release coated urea application could evidently decrease the quantity of soil NO3-N leached to deep soil and lessen the risk to ground water pollution.