油松球果对外源茉莉酸甲酯和虫害诱导的生化反应

Response of Chinese Pine Cones to Induction of Exogenous Methyl Jasmonate and Gravitarmata margarotana Larvae

在松果梢斑螟幼虫转移危害期,研究外源茉莉酸甲酯(MJA)处理和油松球果小卷蛾幼虫危害引起油松球果挥发物、多酚氧化酶(PPO)、蛋白酶抑制剂(PI)以及球果游离氨基酸、松脂和含水量的变化。结果表明小卷蛾幼虫危害后,1年生和2年生球果单萜挥发物种类没有变化,只是含量发生了变化,并且挥发物总量明显增加;2年生球果受害后,α-蒎烯、莰烯、β-水芹烯和β-蒎烯含量下降,而β-月桂烯和D-柠檬烯含量增加,这种成分和挥发量的变化对天敌具有吸引作用。外源MJA处理后,与1年生和2年生受害球果挥发成分有类似的变化,但变化的程度要小得多。外源MJA处理和小卷蛾幼虫危害后,均可引起1年生和2年生球果PPO和PI活性的增加,且1年生球果对2种诱导的反应更敏感。2年生球果受害后,游离氨基酸含量发生变化,含水量下降,松脂含量增加,这表明球果受害后,抗营养和抗消化酶类增加,营养质量下降。

During the transferring-damaging period of the overwinter larvae of Dioryctria pryeri, the terpene volatiles, the polyphenol oxidase （PPO）, α-chymotrypsin inhibitor （ChymPI）, and the free amino acid content, the crude fat and water content of Chinese Pine cones and （or） conelets induced by methyl jasmonate （MJA） and damaged by Gravitarmata margarotana larvae were examined. The results showed that the kinds of the monoterpene volatiles of the conelets and cones could not vary after damaged by the larvae of G. margarotana, but the content of the 6 monoterpene compounds in the infested cone and conelet obviously changed comparing with that in the uninfested cones, and the total content obviously increased. After the 2- year-old cone was damaged, the content of α-pinene, camphene, β-phellandrene and β-pinene decreases, while the content of β- myrcene and D-limonene increased, these changes of the cone volatiles could attract parasite wasps of G. maigarotana and D. pryeri larvae. After exogenous MJA treatment, the variation of the terpene volatiles in the conelet and cone were the same as the infested conelets and cones, but the varying extents were not very high, Meanwhile their PPO and ChymPI activity increased systemically after the conelet and cone was treated by exogenous MJA and damaged by G. maigarotana larvae, and the respone of the conelet to MJA treatment and insect-damage was more sensitive than that of the cone. 17 kinds of the free amino acid content changed, the water content decreased, the crude fat content increased after the cone was damaged. These results showed that the enzyme activity of resistance to nutrition and digestion in the infested cone increased, the nutritive quality decreased.