巨尾桉挥发油对真菌和昆虫的化感作用

Allelopathic effects of essential oil from Eucalyptus grandis × E. urophylla on pathogenic fungi and pest insects

对巨尾桉挥发油对真菌和昆虫的化感潜力及其化学成分进行了研究。结果表明,巨尾桉油乳液对真菌和昆虫均有抑制作用。随着巨尾桉油乳液浓度的增大,其对病原真菌(真菌粉蕉枯萎病菌、水稻稻瘟菌、香蕉胶胞炭疽菌和胡椒疫霉病菌)和有害昆虫(斜纹夜蛾和棉铃虫)的取食和化蛹的抑制作用明显增强。用GC/MS联用方法,对巨尾桉挥发油进行鉴定,相对百分含量在3%以上的化合物有:α-蒎烯(13·63%)、别罗勒烯(43·22%)、γ-萜品烯(5·49%)、(E)-3,7-二甲基-2,6-辛二烯醇(3·58%)、β-小茴香醇(4·58%)和2-氨基-3,5-二氰基-6-(4-甲氧基苯氧基)-吡啶(3·67%)。萜烯类化合物在巨尾桉挥发油对真菌和昆虫的抑制活性中起主要作用,巨尾桉人工林生物多样性较低可能与其化感活性有关。

The study on the allelopathic effects and chemical components of the essential oil from Eucalyptus grandis × E. urophylla showed that the leaf oil emulsion of E. grandis × E. urophylla could inhibit the proliferation of pathogenic fungi Fusarium oxysporum, Pyriculerie grisea, Glorosprium rnusarurn and Phytophthora capsici and the pupation and feeding of pest insects Spodoptera litura Fabricius and Helicoverpa armigera Hubner, with its inhibitory effects increased with increasing concentration. GC/MS analysis on the leaf oil indicated that the main components with a relative content of ≥ 3% were alloocimene （43.22%） , α-pinene （ 13.63% ）, β-terpinene （5.49%）, （ E ） -3,7-dimethyl-, 2,6-octadien-l-ol （ 3.58% ）, β-fenchyl alcohol （4.58%）, and 2-amino-3,5-dicyano-6-（4-methoxyphenoxy）-pyridine （3.67%）. Terpenes played an important role in the inhibitory effects of E. grandis × E. urophylla essential oil on pathogenic fungi and pest insects, and the poor biodiversity of the plantation had relation with the alellopathy.