红树植物秋茄和海莲幼苗过氧化物酶对栽培盐度条件的反应

PEROXIDASE IN TWO MANGROVE SPECIES,KANDELIA CANDEL AND BRUGUIERA SEXANGULA SEEDLINGS,IN RESPONSE TO VARIATION OF SALINITY CONDITION

本文探讨了系列海水盐度砂培的红树植物秋茄和海莲幼苗叶片、根尖的过氧化物酶活性及其同工酶对不同盐度条件的反应。结果表明:(1)秋茄苗:在低盐度0‰至10‰范围,叶过氧化物酶活性随盐度提高而略有增强,15‰以上则降低;根尖过氧化物酶活性则不同,随盐度(0-35‰)提高而降低。(2)海莲苗:随其生长基盐度(5-25‰)提高,叶过氧化物酶活性迅速降低,而根尖过氧化物酶活性在5‰至10‰盐度时略有提高,15‰以上迅速降低;而后高盐度(25-35‰)活性降低不明显。这表明,在盐度的影响下,秋茄苗过氧化物酶活性变化程度小而海莲大。(3)在同工酶谱表现上,两种植物幼苗(叶、根)均为主级酶带受盐度影响不明显,但次级酶带对盐度敏感。

The activity and isozyme of peroxidase in leaf and root tip of the se-edling of two mangrove species, Kandelia candel and Brugulera sexangula,cultivated in sand beds irrigated with seawates of different salinity werestudied. The results showed that,(1) With increase in salinity, the activityof peroxidase in leaf of K. candel got enhanced in lower salinity (from 0to 10) and decreased over 15‰ salinity, but the activity in root tip decr-eased as the salinity increased from 0‰ to 35‰. (2) The activity of pe-roxidase in leaf of B, sexangula declined with increasing salinity from 5‰to 35‰, whereas that in root tip increased with salinity from 5‰ to10‰, and began to decrease over 15. The decreasing trend slowed down inboth leaf and root tip in the range of 25-35‰ salinity. (3) The perox-idase activity of Kandelia was less sensitive to salinity than that of Bru-guiera. The results showed that peroxidase activity may be used as an in-dicator of salinity tolerance, ie. Kandelia can grow in higher salinity th-an Bruguiera. (4) Electrophoresis maps of peroxidase isozyme in two pl-ants on polyacrylamide gel indicated that the main isozyme bands weremore stable than the low-class isozy me bands in response to salinity.