尿素营养斑对小麦苗期根系生长和微域分布的影响

营养斑(Nutrient patch)在土壤中普遍存在。为了摄取养分,植物主动发生生理和形态方面的变化以适应土壤养分分布呈现斑块状这一特性,目前是植物生态学理论的重要议题之一。试验采用自制容器,模拟不同的尿素斑块(对照、尿素混施与尿素条施),观察小麦苗期根系对不同尿素肥斑的响应。结果表明:在尿素混施处理中,小麦根系的微域分布与土壤中铵态氮、硝态氮的微域分布相对应,均呈对称状;而在尿素条施处理中,因此小麦根系与土壤铵态氮、硝态氮的微域分布均呈非对称状,因为营养斑附近集中分布了大部分的氮,过高的氮含量对小麦根系生长造成胁迫,因此小麦的根系形成了背向营养斑生长的微域分布特征。总之,尿素肥斑对小麦根系的生长产生一定的影响,并且根系微域分布是与营养斑内铵态氮、硝态氮分布存在一定的对应关系,这对进一步研究施肥方法对肥料利用率的影响奠定了理论基础。

The Effect of Urea Patch on Root Growth and Spatial Distribution of Wheat in the Seedling Stage

Nutrient patch exists widely in the soil.In order to take up nutrient from soil,plants always change physiological and morphological characteristics to adapt to soil heterogeneity,which is a research focus in phytoecology.In our research,we investigated the response of wheat roots to nutrient patch by using special container in different environments(control,urea mixed application and row application).Root biomass and length in the mixed application of urea were distributed symmetrically within each microco...