具有化感作用的植物能增强花生对黄曲霉毒素的抗性(英文)

Plants with Allelopathic Potentials can Promote the Resistance of Peanut to Aflatoxin

研究三裂叶蟛蜞菊、香根草、香茅对黄曲霉的化感作用。结果表明,三种植物的水提液均能显著抑制黄曲霉的生长。在培养黄曲霉的培养基中加入上述三种植物的水提液后,培养基上黄曲霉的菌落数显著减少,平均菌落直径变小。利用这三种植物的水提液浸泡被黄曲霉感染的花生种子,其发芽率显著高于清水对照处理;显示这三种植物的水提液能够缓解黄曲霉素对花生种子发芽的抑制作用。在没有黄曲霉侵染的条件下,虽然这三种植物的水提液会降低正在发芽的花生种子某些水解酶和保护酶的活性;但在黄曲霉侵染后,这三种植物水提液浸泡过的花生种子水解酶和保护酶的活性却显著高于对照处理,导致处理种子具有更高的呼吸速率、种子活力和发芽率。在对照土壤里,受黄曲霉侵染的种子长出的花生植株长势很差。分别将三种化感植物剪碎、加入土壤中混匀,平衡一段时间;在这些土壤上种植受黄曲霉侵染的种子长出的花生发现能够有效降低黄曲霉素对花生生长的抑制作用。与对照相比,处理土壤上生长的受黄曲霉侵染的花生植株具有更高的根系活力、叶绿素含量、净光合速率、硝酸还原酶和谷氨酰胺合成酶活性,因而具有更高的株高、叶片氮素含量和干物量。

The effect of Wedelia trilobata,Vetiveria zizanioides and Pennisetum schumach on the resistance of peanut to Aspergillus flavus were studied.The results showed that the aqueous extracts of these plants could inhibit the growth of A.flavus.When the aqueous extracts of these plants were added,the number of A.flavus colonies decreased with relatively smaller diameter for each colony.After infected by A.flavus,peanut seeds soaked in the aqueous extracts of these plants had higher germination rate than the control.The result indicated that the aqueous extracts could inhibit the effect of aflatoxin on geminating peanut seeds.Though the aqueous extracts of these plants reduced the activities of some hydrolytic enzymes and some protective enzymes of geminating peanut seeds under the situation without A.flavus infection,when the peanut seeds were infected by A.flavus,the aqueous extracts could increase the protective enzyme activities.This made the treated plants could effectively protect the membrane from the active oxygen and led to the decrease of membrane permeability and the damage of the membrane,so that the seed vitality increased.The increase of hydrolytic enzyme activities made the seeds can provide more energy and materials for the germination.As a comprehensive result,the aqueous extracts increased the respiratory rate and the vitality of the germinating seeds,so that the germination rate increased.The mixture of soil with the little liter of the 3 plants could inhibit the effect of aflatoxin on peanut growth.Peanut seedlings from infected seed by A.flavus grew badly in the control soil.In the treated soil they grew better.They had higher plant height,root activity,fresh or dry root weight,leaf chlorophyll content,net photosynthetic rate and the fresh or dry weight per plant.They significantly increased the activities of nitrate reductase and glutamine synthetase,two key enzymes concerning nitrogen metabolism in plant.The total nitrogen content in the leaves of treated seedlings also increased.