万年鑫， 袁继超， 何卫， 龙文靖， 张琴， 周少猛， 郑顺林*

(1．四川农业大学农学院，农业部西南作物生理生态与耕作重点实验室，成都 611130；2．四川省农业科学院，成都 610066)



马铃薯不同器官浸提液的自毒作用

万年鑫1， 袁继超1， 何卫2， 龙文靖2， 张琴1， 周少猛1， 郑顺林1*

(1．四川农业大学农学院，农业部西南作物生理生态与耕作重点实验室，成都 611130；2．四川省农业科学院，成都 610066)

采用盆栽试验，以不含马铃薯浸提液处理为对照，分析马铃薯不同器官(根、茎、叶)浸提液处理对其生长的影响。结果表明：马铃薯不同器官浸提液对马铃薯生长产生明显的抑制作用。其中，茎、叶浸提液对株高具有显著抑制作用(P<0.05)，化感效应指数( allelopathic response index，RI)均为-0.11；根浸提液对分枝数、茎粗的抑制作用最强，RI值分别为-0.11和-0.13；同时，根浸提液对马铃薯根系的抑制作用也最大，对根表面积、根尖数、分叉数的RI值分别为-0.25、-0.32、-0.32。经不同器官浸提液处理后，马铃薯叶片叶绿素含量、过氧化物酶和过氧化氢酶活性降低；而丙二醛含量随着浸提液质量浓度的升高化感效应降低，且根浸提液的化感效应最强，RI值为-0.10。除根浸提液处理使可溶性糖含量明显增加外，茎、叶浸提液处理使可溶性糖含量降低，RI值达-0.11和-0.02;马铃薯茎、叶浸提液对可溶性蛋白质含量有促进增加的作用，而根浸提液对其产生抑制作用，RI值达-0.06。表明马铃薯不同器官存在自毒作用，但其适应自毒物质胁迫的能力不同，其中，根系自毒作用最为明显。

马铃薯； 浸提液； 自毒物质； 化感作用； 连作障碍

Summary Continuous cropping obstacle caused by intensive cropping of potato has seriously affected its healthy development of industrialization. Autotoxicity was confirmed to be one of the mechanisms causing continuous cropping obstacle; therefore it will be significance to study the autotoxicity of potato for sustainable agriculture production. The growth of plants can be inhibited by autotoxicity through regulating the permeability of cell membrane, affecting the function and enzymatic activities, and even the photosynthesis system. It was so difficult to eliminate the continuous cropping obstacle by agronomic measures, thus it become necessary to solve the problem of continuous cropping obstacle and to reveal the mechanism of autotoxicity for potato.

In this paper, a pot experiment was conducted to investigate effects of water extracts from different organs (root, stem and leaf) of potato on its growth and development. The potatoes were collected from tuber of mature potato in the field, and matrix culture method was adopted to conduct the experiments. Morphological characteristics of root system (root length, root surface area and root volume), and physiological parameters (catalase, peroxidase and malondiadehyde) were used as indicators to study the autotoxicity effect.

The results showed that: Water extracts from different organs of potato exhibited obvious inhibitory effect on the growth of potato, and the extracts from stem and leaves had significant inhibitory effect on the height of potato (P<0.05), with the alleopathic response index (RI) value of -0.11. The root extracts significantly inhibited the number of branches and stem diameter, with the RI value of -0.11 and -0.13, respectively. Meanwhile, the damage of root system caused by the root extracts was also worst, with the RI value of -0.25 for the root surface area, -0.32 for the root tip number, and -0.32 for the branch number, respectively. The chlorophyll contents of potato leaf, activities of peroxidase and catalase all decreased under the treatments of water extracts from different organs of potato; however, the MDA content was increased, and the allelopathic effect of root extracts was the strongest, with the RI value of -0.10. The soluble sugar content was significantly increased by the root extracts, while reduced by the stem and leaf extracts, with the RI value of -0.11 and -0.02, respectively. On the contrary, the soluble protein content was increased by the stem and leaf extracts, while reduced by the root extracts, with the RI value of -0.06.

In conclusion, the autotoxicity effect is observed in different organs of potato, but the adaptation to allelochemicals is distinct among the different organs of potato, and the inhibitory effect by root extracts is strongest.

自毒作用是植物通过根系分泌释放或植株腐解后产生有毒化学物质，影响同种植物种子萌发或对生长起抑制作用的现象，又称自化感作用或自体中毒[1]。自毒物质以挥发、淋溶、根系分泌和残体分解等途径从植物个体(供体)释放，通过改变膜透性[2]抑制植物养分吸收及细胞分裂伸长和亚显微结构，对植物光合与呼吸作用[3]、各种酶功能和活性、内源植物激素合成代谢及蛋白质生物合成[4]等产生一定的影响，从而影响环境中其他同种植物个体(受体)的生长[5]。自毒作用是连作障碍发生机制之一，该作用可使植物品质下降，病虫害增多，进而产生连作障碍[6]。在连作条件下土壤生态环境对植物生长有很大的影响, 尤其是植物残体对植物有致毒作用，并连同植物根系分泌物中的自毒物质影响植株代谢，最后导致自毒作用的发生。……