%0 Journal Article
%T Effects of different N rates on root morphology, yield and fruit quality of lettuce cultivated in plastic greenhouse<br>不同施氮量对大棚莴苣根系形态及产量和品质的影响
%A LU Kou-ping
%A XIE Yin-feng
%A MIN Ju
%A SHI Wei-ming
%A <br>陆扣萍
%A 谢寅峰
%A 闵 炬
%A 施卫明
%J 土壤
%D 2011
%I 
%X Field experiments were carried out to study the effects of different N rates on dynamic changes of root morphological characteristics and the yield and quality of lettuce cultivated in plastic greenhouse. The results showed that as compared with farmer habitual N usage, 40% reduction of N fertilizer input enhanced significantly lettuce root growth, mainly in increasing the root surface area, volume and total root length greatly; but the promotion of nitrogen fertilizer on root diameter was only observed in the late stages of growth. The highest yield and vitamin C contents were obtained in the treatment of 40% reduction of N fertilizer input. Furthermore, nitrate contents of lettuce increased with increase of N fertilizer input. With farmer habitual N usage, nitrate content of lettuce reached as high as to 1 291.9 mg/kg and exceeded the safety standard of safety and quality of agricultural products for root vegetables.
%K Taihu Lake region
%K Greenhouse vegetable
%K Nitrogenous fertilizer
%K Root system
%K Yield
%K Quality<br>太湖地区
%K 大棚蔬菜
%K 氮肥
%K 根系
%K 产量
%K 品质
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=03F54A49DE00578AA0E5DDF5BC021AA7&cid=1A8B5357F0EF07B8&jid=56F69E970C6E5190CDB409D28DD0E3C6&aid=B0A3094CBEF84E912B208044EBCCB409&yid=9377ED8094509821&vid=BE33CC7147FEFCA4&iid=E158A972A605785F&sid=8C044EC256B1039D&eid=4002B7787911C73B&journal_id=0253-9829&journal_name=土壤&referenced_num=0&reference_num=30