温度对刺槐实生苗中过氧化物酶同工酶的影响

<正>酶系统的多型性有很重要的生物学意义。这方面的研究虽还不够充分,但可认为,包括过氧化物酶在内的同工酶参加了个体发育过程和细胞内的调节作用,使植物具有对非生物环境因素的适应能力。温度在对植物起作用的不同生态因素中占有特殊的地位,能决定种的分布界线和不同气候带的植被成分。植物对温度因素的适应机理已研究多年,但至今未建立满意的抗性理论。从另一方面说,植物抗性研究多偏重于低温的作用,往往忽视高温的影响。为此,我们选用对环境适应性较强的刺槐实生苗作为材料,研究高温和低温对过氧化物酶同工酶的诱导作用,为阐明木本植物抗性提供参考。

EFFECTS OF DIFFERENT TEMPERATURES ON THE PEROXIDASE ISOZYMES IN ROBINIA PSEUDOACACIA SEEDLING

Both high and low temperature (40℃ and 4％)have evident effects on peroxidase isozymes in Robinia pseudoacacia seedlings. As compared with what is at the con-trol(25℃), peroxidase activity in Robinia pseudoacacia Seedlings rises to 165.5 and 155% at high and low temperature respectively. In addition, low temperature induces the formation of a slow-migrating peroxidase isozyme (electrophoretic mobility being 0.06), whereas high temperature promotes the synthesis of fast-migrating peroxidase isozymes (electrophoretic mobilities being 0.26, 0.56 and 0.67) and causes the disappearance of two slower-migrating peroxidase isozymes (electrophoretic mobilities 0.10 and 0.17). Synthesis of any protein is an expression of gene, so changes in tempra-ture can induce variation in the expression of individual genes, resulting in syntheses of some enzymes adapted to given temperatures. This may have something to do with the biochemical mechanism of higher adaptability to environmental stress of Robinia pseudoacacia.