%0 Journal Article %A WANG Yi-rong %A ZHAO Yu-long %A WANG Yu %A ZHANG Ke %A TANG Xiao-qing* %T Effects of water and nitrogen interaction on photosynthetic physiology of Isatis indigotica and quality of medicinal material. %D 2016 %R %J Chinese Journal of Ecology %P 3279-3285 %V 35 %N 12 %X In order to provide a theoretical basis for good quality cultivation of Isatis indigotica, a twofactor split plot experiment was designed to explore the effects of water (no waterlogging, W0; slight waterlogging, W1; moderate waterlogging, W2) and nitrogen \[0 mmol·L-1 (N0); 5 mmol·L-1 (N1, low N level); 15 mmol·-1 (N2, moderate N level); and 25 mmol·L-1 (N3, high N level)\] interaction on photosynthetic physiology of I. indigotica and quality of medicinal material with chlorophyll content, photosynthetic parameters, indigo and indirubin contents in leaves, and protein, polysaccharide and epigoitrin in roots as indexes by using pot experiments sheltering from rain. The results showed that water and nitrogen interaction significantly affected photosynthetic physiology of I. indigotica and quality of medicinal material. The chlorophyll content under treatment W2N3, the net photosynthetic rate (Pn) and stomatal conductance (Gs) under treatment W0N2, the intercellular carbon dioxide concentration (Ci) under treatment W0N1 and the transpiration rate (Tr) under treatment W1N2, were the highest among all treatments, respectively, which indicated that photosynthesis and transpiration of leaves were strengthened under N2 level. The epigoitrin content under treatment W2N3, the polysaccharide content under treatment W1N2, the protein content and total nitrogen content under treatment W2N0 in roots, the total nitrogen content, indigo and indirubin content in leaves under treatment W2N0, were the highest among all treatments, respectively. These results illustrate that the secondary metabolism is activated by moderate flooding in short time, and thus the active ingredient contents in leaves and roots would increase. %U http://www.cje.net.cn/EN/abstract/article_22546.shtml