二乔玉兰种子萌发过程中胚乳储藏物质与酶活性的动态变化  

Dynamic changes of storage matter and enzyme activity in endosperm during seed germination of Magnolia soulangeana

作　　者：沈超[1] 王莹[1,2] 张倩云[1] 尹增芳[1] 

机构地区：[1]南京林业大学森林资源与环境学院,南京210037 [2]江苏沿江地区农业科学研究所

出　　处：《林业科技开发》2014年第2期55-58,共4页China Forestry Science and Technology

基　　金：江苏高校优势学科建设工程资助项目(PAPD);镇江市科技计划项目(编号:SYN20090001)

摘　　要：木兰科植物的种子具有后熟休眠特性,造成播种育苗时出苗不整齐。以二乔玉兰种子为试验材料,采用生理生化测定方法,研究了种子萌发过程中水分、储藏物质含量和酶活性的动态变化。结果表明:(1)坚硬种皮对于种子吸水率具有一定的影响。种子含水率在种子萌发初期呈上升趋势,完整种子和去掉坚硬的种皮种子饱和吸水率分别为34.97%和50.7%,但两者保持一致的吸水进程;(2)种子内储藏物质的含量在种子萌发期间逐渐降低,淀粉和粗脂肪的含量在胚根长3 cm时分别下降了0.29%和9.08%。可溶性糖、可溶性蛋白含量在胚根长1 cm时下降速度减慢,随后两者的含量呈缓慢升高的趋势。(3)酸性磷酸酶活性与淀粉酶活性总体呈增强的趋势,其中β-淀粉酶活性最大为α-淀粉酶的11倍,酶活性的变化与淀粉、脂肪含量的变化呈显著性负相关。说明二乔玉兰种子吸水促进了酶活性的增加,有效地降解种子内储存的物质为种子萌发提供的充足的营养物质。Seed dormancy was one of the great problems in nursering for species from Magnolia family. In order to break the dormancy of Magnolia soulangeana seeds, the dynamic changes of the physiological and biochemical traits, such as moisture content, storage matter content and the enzyme activity during the process of the seed germination was investigated. The results were shown as follows： 1） The hard seed coat had some influence on water absorption. Saturated water absorption rate of seed with and without testa were 34.97% and 50.7% respectively, but the water absorption process remained consistently. 2） Storage matter decreased gradually during seed germination. Crude fat and starch content decreased by 0.29% and 9.08% when radicle growth reached around 3 cm length. The soluble sugar, soluble protein content declined at a slower pace when radical length reached around 1 cm , then, both of the content became to rise up slowly. 3） In general, the ACP activity and amylase activity were shown an enhance trend, thereinto, β -amylase activity was 11 times higher than β -amylase activity at the most active condition. A change of enzyme activity was significant negatively correlated with changes of starch and fat content. In conclusion , the increasing trends of enzyme activity was promoted as water absorption increasing of the Magnolia soulangeana seeds, thereby, degraded effectively the storage matter to provide enough nutrients for seed germination.

关 键 词：二乔玉兰 种子萌发 储藏物质 酶活性 

分 类 号：S643.4[农业科学—蔬菜学]