%0 Journal Article
%T Effects of nitrogen application rate on dry matter accumulation, nitrogen efficiency, and potassium and sodium uptake of sweet potato (Ipomoea batatas) in coastal North Jiangsu Province<br>氮肥用量对滨海滩涂区甘薯干物质积累、 氮素效率和钾钠吸收的影响
%A NING Yun-Wang
%A CAO Bing-Ge
%A MA Hong-Bo
%A WANG Ji-Dong
%A ZHANG Hui
%A XU Xian-Ju
%A ZHANG Yong-Chun
%A <br>宁运旺
%A 曹炳阁
%A 马洪波
%A 汪吉东
%A 张 辉
%A 许仙菊
%A 张永春
%J 中国生态农业学报
%D 2012
%I 
%X Sweet potato (Ipomoea batatas) is a high energy crop with great potentials in the coastal areas in China. In order to determine optimum nitrogen (N) application rate (NAR) in sweet potato production, a field experiment was conducted in coastal North Jiangsu Province. Survival rate (SR), commodity rate (CR), dry weight vine-tuber ratio (V/T), dry matter accumulation (DMA), N accumulation (NAV), N use efficiency (NUE), N harvest index (NHI), and potassium (K) and sodium (Na) uptakes of sweet potato were investigated under six N levels (N0~N5). The N levels were 0 kg(N)·hm-2(N0), 60 kg(N)·hm-2 (N1), 120 kg(N)·hm-2 (N2), 180 kg(N)·hm-2 (N3), 240 kg(N)·hm-2 (N4), and 300 kg(N)·hm-2 (N5), respectively. The results were summarized as follows: (1) A sig-nificant positive correlation was noted between NAR and aboveground DMA or NAV at P < 0.01, but no significant correlation ex-isted between NAR and root NAV at P > 0.05. (2). Compared with N0, N1 treatment had no significant effects on sweet potato V/T, SR, NUE and NHI. (3) Sweet potato CR, root and tuber DMA as well as theoretical yield (TY=NAV×NUE×NHI) were highest under N1 treatment. When sweet potato NARs were 60~300 kg(N)·hm-2 , significant positive correlation existed between NAR and V/T at P < 0.01. However, significant negative correlation was noted among SR, CR, NUE, NHI, root and tuber DMA of sweet potato at P < 0.01. (4) There was significant positive correlation between K and Na uptake at P < 0.01; both of which increased with increasing NARs. K and Na contents of aboveground tissues of sweet potato under N1 treatment were significantly higher than those under other treatments. However, K/Na ratio for the whole plant was not different among treatments. The study suggested that the optimum NAR in sweet potato fields in coastal North Jiangsu Province was 60 kg(N)·hm-2.
%K Coastal North Jiangsu Province
%K Sweet potato
%K Dry matter accumulation
%K Nitrogen efficiency
%K Potassium/sodium uptake<br>滨海滩涂
%K 甘薯
%K 干物质积累
%K 氮素效率
%K 钾钠吸收
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=03F54A49DE00578AA0E5DDF5BC021AA7&cid=1A8B5357F0EF07B8&jid=AB3ABF502E2E1FF39F0E3B80164C9031&aid=8A6EC9640C158E7BEAE74CF491A570CF&yid=99E9153A83D4CB11&vid=A04140E723CB732E&iid=5D311CA918CA9A03&sid=7D89C25BE291E00C&eid=54D3D9B69F1CCE77&journal_id=1671-3990&journal_name=中国生态农业学报&referenced_num=0&reference_num=0