Effects of water and nitrogen coupling on photosynthetic characteristics of fluecured tobacco in the resettling growth stage | 水氮耦合对烤烟团棵期光合特性的影响研究

中国人. 以K326为试验材料，采用赣北代表性土壤进行盆栽，探讨不同水氮耦合条件下烤烟团棵期的光合特性。结果表明：水氮耦合和与烤烟团棵期叶绿素含量、净光合速率（Pa）、蒸腾速率（Tr）和气孔导度（Cond）存在显著相关，与胞间CO2浓度（Ci）存在显著负相关。每株用氮8．5g，相对土壤含水量为70％～80％，叶绿素含量、净光合速率（CO2）达最大值，分别为2．93mg／g、14．05μmol／m. ・s；胞间浓度（CO2）达最低值为200μmol／mol。每株用氮7．0g，相对土壤含水量为70％～80％，气孔导度（H2O）达最大值，为0．26mol／m. ・s。蒸腾速率随土壤含水量增加而增大，随氮肥用量增加而减少。生产中可以采用高肥高水（处理B3W4，即每株用氮8．5g，相对土壤含水量为70％～80％）提高叶绿素含量和净光合速率，降低胞间CO2浓度；在烤烟团棵期土壤相对含水率较高的地区可以采用中肥高水（处理B2W4，即每株用氮7g，相对土壤含水量为70％～80％）减少经济投入；在烤烟团棵期土壤相对含水率较低的地区可以增加氮肥用量减小蒸腾速率，提高田间的水分含量。[著者文摘]

英语. The photosynthetic characteristics of potted flue - cured tobacco in the resettling growth stage under different conditions of water and nitrogen coupling were probed. K326 and the typical soil in northern Jiangxi Province were taken as the test materials. The result showed that： water and nitrogen coupling has a significant relation with chlorophyll content, Pn, Tr and Cond of flue - cured tobacco in the resettling growth stage, but a negative relation with Ci. Under the conditions that nitrogen 8.5 g,relative soil moisture 70% ～ 80%, the chlorophyll content and Pn of each plant reached the maximum values：2. 93 mg/g and 14. 05μmol/m2・s （CO2 ） respeetively;Ci concentration reached the lowest count of 200 μmol/mol（ CO2 ）. Under the conditions that nitrogen 7.0 g,relative soil moisture 70% ～ 80%, Cond of each plant reached the maximum of 0.26 mol/m2・s（H2O）. Tr increased with soil moisture increasing and decreased with the amount of nitrogen fertilizer reducing. B3W4 could increase chlorophyll content and Pn ,and reduce the Ci in production. In the area with a relatively high moisture content during the resettling stage of flue - cured tobacco the economic input could be reduced by the treatment of B2W4 ;in the area with a relatively low moisture content during the resettling stage Tr could be reduced and the water content of the field improved by increasing the amount of nitrogen.