不同种源羊草表型差异性

Variations of phenotypic characteristics in Leymus chinensis among different provenances

研究植物因环境变化产生的表型差异,对于其适应未来全球气候变化具有重要的意义。羊草具有广泛的地理分布,是研究表型差异的理想材料。将白城市镇赉种源地羊草(ZL),白城市洮北种源地羊草(TB),吉林大安市种源地羊草(DA)和大安市姜家甸草场种源地羊草(JC)进行同质园移栽培养,分析了4个种源羊草的表型特征。结果表明,不同种源间羊草表型特征株高、叶长、叶宽、茎直径和生理特征蒸腾速率(Tr)、水分利用效率(WUE)和生物量分配均存在显著差异。在同质园环境培养下,这些表型特征均存在显著的种源差异。从总体上来看,TB种源地的羊草具有最高的株高、叶长和叶宽,分别为72.2 cm、34.4 cm、和10.34 mm。ZL种源有着最高的生物量(46.05 g)和WUE(3.06μmolCO2/mmol H2O)。ZL种源叶鲜重和干重均表现出了较高值,分别为2.88 g和0.96 g。不同种源羊草经移栽到同质园环境下,因为对源地气候长期的适应,产生了明显的表型差异,进而引起形态、生理特征的差异。这有利于羊草适应未来剧烈的气候变化,进一步揭示了羊草适应环境的策略。

Phenotypic characteristics are one of the most valuable parameters for understanding the adaptation of plants to climatic changes.Leymus chinensis,a dominant perennial grass,is widely distributed in the eastern Eurasian Steppe,providing an ideal case study for investigating phenotypic variation across an environmental gradient.In this study,seedlings of L.chinensis were transplanted from the four provenances Zhenlai,Taobei,Da′an,and Jiangjiadiancaochang and grown in a common garden.The aim was to investigate phenotypic plasticity among the four provenances.We measured plant height,leaf length,leaf width,dry weight,water use efficiency(WUE),specific leaf area(SLA),and biomass allocation of plants grown in the common garden.The results indicated that plant height,WUE,SLA,transpiration rates(Tr)and dry weight differed significantly among the four provenances.Taobei provenance plants had the largest plant height,leaf length,and leaf width,which were 72.2 cm,34.4 cm and 10.34 mm,respectively.Zhenlai provenance plants had the greatest biomass and WUE of 46.05 g and 3.06μmol CO2/mmol H2O and also presented higher fresh and dry weights of 2.88 g and 0.96 g,respectively.There were no significant differences between provenances for net photosynthetic(Pn)and tiller number.These phenotypic and physiological variations found are likely to be a result of long-term environmental adaptation of L.chinensis,which could be conducive to its adaptation to climatic change in the future.