菜青虫感染金龟子绿僵菌后体内几种保护酶活性的变化

Changes of protective enzyme activities in Pieris rapae infected by Metarhizium anisopliae

为了明确菜青虫感染金龟子绿僵菌后体内的防御机制,采用分光光度法测定了菜青虫被金龟子绿僵菌感染后体内保护酶活性的变化。结果表明,用金龟子绿僵菌处理后菜青虫体内超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)均呈现先上升后下降趋势,反映出菜青虫在金龟子绿僵菌侵染初期防御能力增强,后期降低。其中,SOD、POD和CAT活力分别在接种后36、24和48h达到高峰,说明菜青虫在抵抗金龟子绿僵菌侵染过程中,首先发生作用的保护酶是POD,随后为SOD,而CAT是最后发生作用的保护酶。

To understand the defense mechanisms of Pieris rapae against Metarhizium anisopliae,this study used spectrophotometry to assay the activities of protective enzymes of P.rapae infected by M.anisopliae.The results indicated that,the activities of SOD,POD and CAT in the infected P.rapae were increased at initial infection stage,but dropped at the later infection stage,suggesting that the defense system of P.rapae was enhanced during initial period,but dropped during the later period.The highest activities of SOD,POD and CAT were observed at 36 hours,24 hours and48 hours after inoculation,respectively,which indicated that POD played an important role in defending against the invasion of M.anisopliae,and then SOD functioned after invasion,while the last effective protective enzyme was CAT.