牛大力种子萌发过程中的生理生化变化

Physiological and Biochemical Changes During the Germination of Callerya speciose Seeds

关键词:  牛大力  种子萌发  生理生化  可溶性糖  抗氧化酶  蛋白酶  总酚

Key words:  Callerya speciosa  seed germination  physiology biochemistry  soluble sugar  antioxidase  endopeptidase  total polyphenols

摘要:

本文在于研究种子萌发过程中生理生化变化规律，为牛大力（Callerya speciosa）种苗培育提供理论支撑。对牛大力种子萌发时期可溶性糖、抗氧化酶活性、游离氨基酸、蛋白酶、总酚含量进行测定，研究牛大力种子萌发不同时期的各项生理生化指标的动态变化，并比较他们之间的相关性。在牛大力种子萌发过程中，22 d时可溶性糖含量达到最高值，为0.430 mg·g^-1，随后持续降低。超氧化物歧化酶（SOD）活性、过氧化氢酶（CAT）活性在22 d达到最高值，分别为300.28，810 U·g^-1 FW，过氧化物酶（POD）活性在萌发过程第17 d达到最高值，为240 U·g^-1 FW，这3种抗氧化酶活性均呈现先升高后下降的趋势；游离氨基酸呈先升后降再陡然上升的趋势；蛋白酶活性在第22 d时达到最大值，为1.101 mg·g^-1·h^-1，呈先升后降的趋势；总酚含量在0 d时最高，为77.81 μg·g^-1，随后出现无规律性变化，但总体呈降低趋势。相关性分析表明，牛大力种子萌发过程中，物质和能量代谢与POD、CAT及蛋白酶等的作用有很大关系；POD、CAT在种子萌发过程中不仅能消除植物体内产生的过氧化氢等有害物质，也可能在一定程度上参与了种子的其他代谢活动；总酚在种子萌发过程中通过抑制SOD酶活性影响牛大力种子的萌发。

Abstract:

This article is to study the physiological and biochemical changes in the process of seed germination,and to provide theoretical support for the cultivation of Callerya speciosa seedlings.The contents of soluble sugar,antioxidant enzymes,amino acid,endopeptidase and total polyphenols were determined during the germination period of C.speciosa.The dynamic changes of physiological and biochemical indexes of C.speciosa seeds at different germination stages were studied,and the correlation between them were compared.The soluble sugar content reached the highest value at 22 d,which was 0.430 mg·g^-1,and then continued to decrease during the germination of C.speciosa seeds.The activities of superoxide dismutase (SOD) and catalase (CAT) reached their highest values at 22 d,respectively 300.28,810 U·g^-1 FW. The activity of peroxidase (POD) reached its highest value on the 17th day of germination,which was 240 U·g^-1 FW.The activities of these three antioxidant enzymes all showed a trend of increasing first and then decreasing.Free amino acid showed a trend of rising first,then falling,and then suddenly rising.The endopeptidase activity reached the maximum value of 1.101 mg·g^-1·h^-1 at 22 d,showing a trend of rising first and then decreasing.The total polyphenols content reached the highest value at 0 d,which was 77.81 μg·g^-1,but then changed irregularly,and showed a decreasing trend overall.Correlation analyses showed that,during the germination of C.speciosa seeds,the metabolism of substances and energy had a great relationship with the effects of POD,CAT and protease.During seed germination,POD and CAT could not only eliminate harmful substances such as hydrogen peroxide and so on produced in plants,but also participate in other metabolic activities of seeds to some extent.Total polyphenols affected the germination of C.speciosa seeds by inhibiting the activity of SOD enzyme during the seed germination.