作 者 :张国良,陈文军,王显,金添,戴其根*,孙国荣,许轲,霍中洋,张洪程
期 刊 :生态学报 2008年 28卷 9期 页码:4388~4395
关键词:4-三氯苯;小麦;耐性基因型;敏感基因型;毒性;抗氧化酶;
Keywords:1, 2, 4-trichlorobenzene, wheat, tolerant genotype, sensitive genotype, toxicity, antioxidant enzymes,
摘 要 :通过砂培试验,研究了6种浓度(0、0.3、0.6、1.0、1.5 mmol/kg沙和2.0 mmol/kg沙)的1, 2, 4-三氯苯(TCB)对两种小麦烟辐188(耐性基因型)和扬麦16(敏感基因型)种子发芽率、发芽指数、幼苗生物量、以及叶片和根系的蛋白质含量、丙二醛含量(MDA)、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、过氧化氢酶(CAT)活性等生理指标的影响。结果表明两种小麦基因型具有显著的差异,在TCB胁迫下,烟辐188的种子发芽率、发芽指数、幼苗生物量均高于扬麦16,烟辐188和扬麦16的叶片可溶性蛋白含量分别与对照差异不显著和显著偏低。随着TCB浓度的升高,烟辐188根系的可溶性蛋白含量呈上升趋势,与对照差异显著,而扬麦16先略有上升然后呈下降趋势,且显著低于对照。TCB胁迫导致扬麦16叶片SOD、POD活性小于对照,CAT活性显著小于对照;而烟辐188叶片SOD活性与对照间差异不明显,POD和CAT活性在低浓度TCB胁迫时与对照差异不大,在高浓度时小于对照,其MDA含量低于扬麦16。烟辐188根系SOD、POD活性对TCB胁迫不敏感,扬麦16 SOD、POD活性受O-?2诱导而上升,但由于其O-?2产生速率要大于烟辐188,仍然不能清除多余的O-?2,最终其根系MDA含量高于烟辐188。总体而言,TCB胁迫下烟辐188的发芽情况、幼苗生长情况和生理指标均好于扬麦16,表现出对TCB胁迫有较强的耐受性和适应性。
Abstract:Wheat seeds germination and seedling growth were investigated to study the physiological response of Yanfu 188 and Yangmai 16 to TCB toxicity. The influence of increasing concentrations of TCB (0、0.3、0.6、1.0、1.5 mmol/kg sand and 2.0 mmol/kg sand)on the germination rate and germination exponential of wheat seeds, the biomass of wheat seedling were measured. Soluble protein content, malnodialdehyde (MDA) content, superoxide dismutase (SOD) activities, peroxidase (POD) activities, and catalase (CAT) activities of both leaves and roots were also measured. TCB had obvious toxicity to wheat, and there was significant difference (P<0.05) between Yanfu 188 and Yangmai 16. The seed germination rate, germination exponential and the seedling biomass of Yanfu 188 were higher than those of Yangmai 16. No significant difference (P>0.05) was observed between the control and the treatment on the leaf soluble protein content of Yanfu 188 under TCB stress, but the leaf soluble protein of Yangmai 16 were significantly lower (P<0.05) than the control. With increasing TCB level, the root soluble protein content of Yanfu 188 increased, significantly different with the control. While that of Yangmai 16 increased firstly, then significantly decreased. Under TCB stress, the activities of SOD, POD in Yangmai 16 leaves were lower than control, and the activity of CAT was significantly lower than control. SOD activity in Yanfu 188 leaf was similar with the control. POD and CAT activities in Yanfu 188 leaf was similar with the control under low concentrations, while lower than the control under high concentrations. MDA content in Yanfu 188 was lower than in Yangmai 16. The activities of SOD, POD in Yanfu 188 roots were not sensitive to TCB stress, while those in Yangmai 16 root increased with the concentration of TCB, under induction of O-·2. Since O-·2 producing velocity in Yangmai 16 was greater than Yanfu 188, it could not eliminate excessive O-·2, which led to its higher MDA content. In conclusion, the germination, seedling growth and physiological function of Yanfu 188 were better than Yangmai 16 under TCB stress, and Yanfu 188 was not adversely impacted by TCB.
全 文 :