几个引种苜蓿品种的生理适应性研究

Study on physiological adaptability of four introduced alfalfa(Medicago sativa) cultivars

采用Li-6400便携式光合测定系统,测定已在内蒙古多伦县广泛种植的草原三号及4个引种苜蓿品种(甘农三号、新疆大叶、皇后苜蓿和中兰一号)的净光合速率(Pn)、蒸腾速率(Tr)日变化及其对生理因子、环境因子的响应,并测定生物量。结果表明:(1)皇后苜蓿的生物量(383.3g/m^2)与草原三号的(417.8g/m^2)均较高无显著性差异,新疆大叶、中兰一号和甘农三号生物量分别为325.7,167.7和161.4g/m^2;(2)草原三号、皇后苜蓿和新疆大叶Pn和Tr为"双峰型",甘农三号和中兰一号Pn和Tr为"单峰型";(3)草原三号Pn为10.649μmol/(m^2·s),Tr为4.963mmol/(m^2·s),均最高,引种品种以皇后苜蓿Pn9.195μmol/(m^2·s)和Tr4.919mmol/(m^2·s)最高;(4)光合有效辐射是影响草原三号Pn的主导因子,胞间CO2浓度和相对湿度为影响引种苜蓿品种Pn的主导因子;Gs为影响5个苜蓿品种Tr的主导因子。(5)"双峰型"引种苜蓿品种对当地生态环境的适应性强于"单峰型"。根据4个苜蓿品种在该地的光合特性和生物量表现,认为皇后苜蓿可作为内蒙古多伦县人工草地建植引种的备选品种。

Net photosynthetic rate（Pn）and transpiration rate（Tr）of Medicago varia cv.Caoyuan No.3（locally grown）and 4introduced alfalfa cultivars（M.sativacv.Gannong No.3,M.sativacv.Xinjiang Daye,M.sativacv.Queen and M.sativacv.Zhonglan No.1）were measured with LI-6400 portable photosynthesis system at Duolun County in Inner Mongolia.The response of Pnand Trto physiological factors and environmental factors was studied as well.The results indicated that 1）the biomass difference between Queen（383.3g/m^2）and Caoyuan No.3（417.8g/m^2）was not significant,which were followed by Xinjiang Daye（325.7g/m^2）,Zhonglan No.1（167.7g/m^2）and Gannong No.3（161.4g/m^2）.2）Diurnal variation of Pnin Caoyuan No.3,Queen and Xinjiang Daye showed a double peak curve,while Gannong No.3and Zhonglan No.1showed a single peak curve.3）Pnand Trof Caoyuan No.3were 10.649μmol/（m^2·s）and 4.963 mmol/（m^2·s）,Queen had the highest Pnand Tramong 4introduced cultivars（9.195μmol/（m^2·s）and 4.919mmol/（m^2·s）respectively）.4）PAR（Photosynthetic available radiation）was the key factor affecting Pnof Caoyuan No.3,Ciwas the key factor affecting Pnof the introduced cultivars.Considering Pn,Trand biomass,Queen was the best cultivar for the establishment of artificial grassland in Inner Mongolia.