【摘要】 以盆栽方式研究了苗期菘蓝生长及气体交换参数对不同浓度的酰胺态氮施用次数的响应。结果表明:苗期施用适宜浓度的酰胺态氮能有效地提高菘蓝叶片的叶绿素相对含量(SPAD值)、净光合速率(Pn)、蒸腾速率(Tr)与胞间二氧化碳浓度(Ci),也能有效促进主根直径、单株叶与根的鲜质量,其中以浓度为1.0%~1.5%的酰胺态氮施用2次的促进作用明显;建议在菘蓝营养生长前期以促进生长为目的,施用1.0%~1.5%的纯脲有利于其生物量的积累。更多还原

【Abstract】 The responses of the growth and gas exchange parameters of Isatis indigotica seedlings to amide nitrogen applied at different levels and frequencies were studied. The results showed that application of amide nitrogen at a suitable concentration increased leaf chlorophyll relative content( SPAD),net photosynthetic rate( Pn),transpiration rate( Tr) and intercellular carbon dioxide concentration( Ci) in I. indigotica leaves,and obviously improved the taproot diameter,the fresh weights of leaves and roots,in which the promoting effect of application two times of1. 0%- 1. 5% amide nitrogen was more stronger. It was suggested that 1. 0%- 1. 5% pure urea could be used for improving the biomass accumulation of leaves and roots in the pre-stage of I.indigotica seedling cultivation.更多还原