中文摘要：

为揭示不同水氮耦合的促根机理,该文以日光温室冬春茬和秋冬茬黄瓜根系为主要研究对象,应用主成分分析法对根系生长情况进行综合评价,探索有效根直径范围内根系根长密度在土壤中的分布与不同土层间NO3--N含量之间的关系。结果表明：该文得到的综合主成分可以代表97.27%的根系信息,综合评价最高的处理为优化灌溉定额为300 m3/hm2时,冬春茬共灌溉8次,优化施氮量240 kg/hm2、秋冬茬共灌溉5次,施氮量50 kg/hm2,该水肥管理条件能够更好地促进黄瓜根系的生长,提高了日光温室黄瓜的产量,降低了氮肥及水资源的浪费,是日光温室黄瓜的优质高效施肥灌溉模式。

英文摘要：

To explore the promoting root mechanism of coupling of water and nitrogen,taking root growth of winter-spring cucumber and autumn-winter cucumber in solar greenhouse as a research object,the principle component analysis method was used to evaluate the root growth,the relationship between NO3--N content in different soils depth and distribution of root length density of root system in soil in effective root diameter was studied.The results showed that quality principle component could represent 97.27% primordial root information;the water management（irrigation quota was 300 m3/hm2 with irrigation scheduling of eight times for the winter-spring cucumber and five times for the autumn-winter cucumber） and suitable nitrogen application（240 kg/hm2 for the winter-spring cucumber and 50 kg/hm2 for the autumn-winter cucumber） situation could keep the soil NO3--N content in root zone appropriate for cucumber growth,increase yield of cucumber and reduce the wasting of water and nitrogen fertilizer,which the coupling mode of applying water and nitrogen with high quality and efficiency.