摘要： 探讨了外源酚酸类物质对马铃薯植株生长发育的影响及其机制。对羟基苯甲酸、香草酸和阿魏酸这3种酚酸类化合物是连作马铃薯土壤中重要的化感物质,分别浇灌这3种酚酸的溶液及其混合液对马铃薯植株的株高、茎粗、地上分茎数、匍匐茎数、根长和生物量皆有显著抑制作用,且混合酚酸溶液的抑制效果大于相同浓度的这3种酚酸溶液中任一溶液。结果还显示,外源酚酸处理显著降低了马铃薯植株的根系活力、叶片叶绿素含量和叶片净光合速率,且上述作用随着酚酸溶液质量浓度(从50 mg/L至200 mg/L)增加而显著增加,这些影响对于植株的生长发育可能具有直接且重要的作用。关于叶片脂质过氧化程度的检测表明,150,200 mg/L外源酚酸处理显著提高了叶片的MDA含量,并对应着抗氧化酶活性的整体下降,并以混合酚酸的效果最为显著;可见,150,200 mg/L的外源酚酸溶液处理可对马铃薯叶片产生持续而明显的胁迫,并造成抗氧化酶系统功能的下降及膜质过氧化程度的增加,这一结果与前述外源酚酸抑制植株的生长发育、根系活力和叶片光合速率是相对应的,上述研究结果对于从感化物质累积的角度理解及调控马铃薯连作障碍具有一定的价值。

关键词: 马铃薯, 连作障碍, 酚酸, 化感物质, 生长发育, 抗氧化酶

Abstract: This paper probed the effects and mechanism of exogenous phenolic acids on potato 's growth and de-velopment.Para hydroxy benzoic acid, vanillic acid and ferulic acid are the three most important allelochemicals ( phe-nolic acids ) in potato continuous cropping soil, when the potato seedlings were irrigated with the three kinds of phe-nolic acids solution and its mixture respectively, the plant height,stem diameter,aerial stem number,stolon number and root length were reduced significantly, and at the same concentration of phenolic acid solution, the inhibition of the their mixture was stronger than that of each phenolic acid solution.The results also showed that the treatment of exogenous phenolic acids significantly reduced the potato's root activity, leaf chlorophyll content and leaf net photo-synthetic rate, and the inhibitory effects increased significantly as the phenolic acid solution concentration increased from 50 mg/L to 200 mg/L.These effects described above should play a direct and important role in the growth and development of the plants.The tests about the lipid peroxidation of the potato plantlets'leaves showed that the treat-ment of exogenous phenolic acids increased the leaves'MDA content significantly, and were corresponds to the decline in antioxidant enzyme activity, as the concentration of exogenous phenolic acids solution increased ( from 100 mg/L to 200 mg/L) the effect was strengthened, and the mixed phenolic acids'effect was the most significant under the same concentration.So it can be concluded that exogenous phenolic acids treatments caused continuous and significant stress on the potato's leaves, and resulted in the reduction in the function of antioxidant enzyme system, and thus re-sulted in the increase in lipid peroxidation degree.The results were corresponded to the results that the exogenous phenolic acids treatment inhibited the plants growth, root activity and leave net photosynthetic rate.The above results of this paper may promote the understanding and regulation in potato continuous cropping obstacle.

Key words: Potato, Continuous cropping obstacle, Phenolic acids, Allelochemicals, Development, Antioxidative enzyme

中图分类号: 

• S532