赤霉素浓度对色木槭(Acer mono Maxim.)种子萌发的影响

Effect of gibberellin concentration on seed germination of Acer mono Maxim.

岷江上游彩叶林生态系统是我国西南地区特有的关键生态系统类型,具有水源涵养、水土保持和气候调节等重要的生态功能,而且具有显著的景观美学价值,是区域特色生态旅游经济的重要基础.由于受到自然灾害破坏和水电站的修建等人为干扰,目前岷江上游彩叶林系统毁坏严重且残存量不多,亟待恢复和重建.色木槭(Acer mono Maxim.)是川西地区彩叶林生态系统的代表性树种,探究其种子萌发特性对岷江上游彩叶林系统的恢复重建具有重要意义.种子萌发实验在人工气候箱内进行,采用0、100、200、300、400、500 mg/L 6个赤霉素浓度对色木槭种子进行浸种处理,在25℃条件下进行萌发,统计种子萌发率、发芽势和发芽指数,并测定色木槭种子在萌发过程中内部贮藏物质可溶性糖、可溶性蛋白、淀粉和淀粉酶活性的变化.结果显示,色木槭种子在200 mg/L浓度赤霉素浸种24 h后,其萌发率为29.33%±1.89%,发芽势为9.66%±1.25%,发芽指数为8.69±8.32,均显著高于对照水平.本研究表明赤霉素浓度对色木槭种子的可溶性蛋白含量、淀粉含量和淀粉酶活性影响显著,对可溶性糖含量无显著性影响;种子内部贮藏物质含量在不同的萌发时期有显著差异.色木槭种子的最适赤霉素浓度为200 mg/L,在生产中使用200 mg/L赤霉素浸种能有效增加色木槭的萌发率.上述结果可为色木槭的快速繁育和亚高山彩叶林恢复重建提供技术支持.

The colored-leaf forest is a distinctive ecosystem in the upper reaches of the Minjiang River in Southwest China.It not only has important ecological functions,such as soil and water conservation and climate regulation,but also has a unique value for landscape esthetics,which is the foundation of the regional ecotourism economy.Owing to natural disasters,construction of hydropower stations,and other anthropogenic disturbances,the colored-leaf forest in the upper reaches of the Minjiang River has been seriously damaged,and there are only a few residual forests remaining.Therefore,restoration and reconstruction are critically needed.Acer mono Maxim.is a representative colored-leaf tree species in Southwest China,and exploring its seed germination characteristics is of great significance to the restoration and reconstruction of the coloredleaf forest ecosystem in the upper reaches of the Minjiang River.A seed germination experiment was conducted in an artificial climate chamber.The seeds of A.mono were soaked in gibberellin at six concentrations(0,100,200,300,400,and 500 mg/L)and germinated at 25°C.Seed germination rate,germination vigor,and germination index were recorded,and the changes in internal storage substances such as soluble sugar,soluble protein,starch,and amylase activities during the seed germination process were identified.The concentration of gibberellin had a significant effect on seed germination.After soaking with 200 mg/L gibberellin,the seed germination rate of A.mono was 29.33%±1.89%,germination potential was 9.66%±1.25%,and germination index was 8.69%±8.32%.The concentration of gibberellin also had a significant effect on the soluble protein content,starch content,and amylase activity of A.mono seeds but had no significant effect on the soluble sugar content.The internal storage substance content in seeds was significantly different at different germination stages.The optimum concentration of gibberellin for seed germination of A.mono was 200 mg/L.Soaking seeds with 200 mg/L gibberellin can effectively increase seed germination rate.