渗透胁迫对山黧豆幼苗H_2O_2及毒素积累的影响

用PEG经根部处理 15d龄的山黧豆幼苗 ,取幼苗叶片为实验材料 ,测定过氧化氢酶 (CAT)、过氧化物酶 (POD)活性、过氧化氢 (H2 O2 )和毒素 ( β N oxalyl α ,β diaminopropionicacid ,ODAP)的含量。结果表明 ,随着PEG处理时间的延长 ,POD和CAT活性降低 ,而H2 O2 和ODAP含量显著升高 ;在PEG处理液中加入二乙基二硫代氨基甲酸钠 (diethyldithiocarbamate ,DDC)和氨基三唑 (aminotriazole ,AT)后分别抑制和促进H2 O2 的产生 ,DDC可降低叶片中ODAP的含量 ,AT则使ODAP积累。由此我们推测 ,水分胁迫条件下活性氧代谢与ODAP的积累有关

Effects of Osmotic Stress on Accumulation of H_2O_2 and ODAP in Grass Pea ( Lathyrus sativus )

Roots of fifteen-day-old grass peaseedlings were treated with PEGand then theleaves were used as material. Changes in activ-ities of catalase and peroxidase, and hydrogenperoxide and β-N-oxalyl-α, β-diaminopropi-onic acid (ODAP) contents during PEG treat-ment, were assayed. The results indicated thatduring PEG treatment, activities of peroxidaseand catalase decreased ( Fig. 3 ), and hydrogenperoxide ( Fig. 2 ) and ODAP content ( Fig. 1 )increased greatly. Diethyldithiocarbamate or a-minotriazole strongly decreased or increased re-spectively the H2O2 content ( Fig. 2 ). Whilethe accumulation of ODAP was decreasedmarkedly by diethyldithiocarbamate, it was in-creased significantly by aminotriazole ( Fig. 1 ).Therefore, we suggest that the accumulation ofODAP might be related to the increase in H2O2content under osmotic stress.