土壤干旱胁迫对樟子松针叶膜脂过氧化、膜脂成分和乙烯释放的影响

本文采用对盆栽樟子松苗木进行土壤干旱胁迫处理的办法，研究其针叶ＳＯＤ活性水平、ＭＤＡ含量以及膜脂成分和乙烯释放量的变化。结果表明：随着干旱胁迫的加强，ＳＯＤ活性呈现先上升后下降的趋势，ＭＤＡ含量逐渐上升到最高水平，在严重干旱末期下降，但仍处于高水平；ＩＵＦＡ在严重干旱胁迫下开始下降，乙烯伴随着ＩＵＦＡ水平明显的下降而产生，同时苗木走向死亡。这些结果表明樟子松针叶受土壤干旱胁迫，酶促保护系统破坏导致

EFFECT OF DROUGHT STRESS ON THE PEROXIDATION OF MEMBRANE LIPIDS,THE COMPOSITION OF MEMBRANE FATTY ACIDS AND ETHYLENE EVOLUTION OF NEEDLES OF PINUS SYLVESTRIS VAR. MONGOLICA LITV

In this paper the potted seedlings of %Pinus sylvestris% var. %mongolica% Litv. were treated by soil drought stress to study the activity levels of SOD, MDA content, the composition of membrane fatty acids and the amount of ethylene release of needles. The results showed that the SOD activity levels first increased and then decreased with the aggravating of drought stress; The change trends of MDA content was to increase to the highest level, and then decrease to a still high level; IUFA started to decrease under serious stress; Ethylene released obviously when the IUFA level dropped drastically, at the same time the seedlings began to die. These results show that be the drought stress damage of needles of %Pinus sylvestris% var. %mongolica% Litv. is caused by membrane|lipid peroxidation; the increase of MDA content aggravates peroxidation, which causes the obvious decrease of IUFA level and ethylene evolution, and then seedlings begin to die.