柑橘木虱胁迫对柠檬叶代谢组挥发性成分的影响

The effect of Diaphorina citri Kuwayama on metabonomics volatile compounds in Citrus limon Burm leaves

柑橘木虱是柑橘黄龙病的自然传播媒介,为了解柑橘应对柑橘木虱胁迫的代谢组学变化,本文以柠檬为受体,进行柑橘木虱取食胁迫处理,分别于胁迫不同阶段(0、12、24、48、72和96h)采集柠檬叶为试验材料,静态顶空-气相色谱-质谱联用检测其挥发性物质。主要结果如下:结合保留指数从柠檬叶中共检出37种化合物,包含15种萜类,6种醛类,6种醇类等;含量较高的挥发性成分有(+)-柠檬烯、桧烯、月桂烯等;受柑橘木虱取食胁迫后,柠檬叶中的挥发性化合物含量产生明显变化,萜类、醛类和醇类物质相对含量均呈升高趋势。桧烯、里那醇、(+)-香茅醛和橙花醇4种物质的含量在柑橘木虱取食胁迫96h时分别升高2.1,2.9,7.8和3.2倍;α-石竹烯的含量下降1.9倍。(+)-柠檬烯、β-红没药烯和反式-α-香柑油烯等物质含量变化不明显,胁迫后的样品中新检出玫瑰呋喃氧化物、香叶醇和2-异丙基-5-甲基茴香醚等3种化合物。皮尔森相关性分析表明,桧烯、β-蒎烯、甲基庚烯酮、月桂烯、水芹烯等9种物质含量与柑橘木虱胁迫时间呈极显著正相关(P<0.01),α-蒎烯、莰烯、松油烯、γ-萜品烯等10种物质含量与柑橘木虱胁迫时间呈显著正相关(P<0.05),而邻甲氨基苯甲酸甲酯含量与柑橘木虱胁迫时间呈极显著负相关(P<0.01)。聚类和热图进一步分析表明,胁迫不同时间的样品具有显著差异,且胁迫时柠檬叶挥发性化合物大部分呈现上升的趋势,尤其是胁迫48、72和96h后,物质含量显著增加。研究结果为了解柑橘应对柑橘木虱等生物胁迫的代谢组学变化及柑橘木虱的生物防治提供了理论基础。

Diaphorina citri Kuwayama is the natural vector of the citrus Huanglongbing.In order to investigate the changes of metabolic in citrus leaves in response to D.citri stress.Citrus limon Burm was used as the receptor for D.citri feeding stress treatment,and then leaves were collected at 0,12,24,48,72,96 h after feeding stress,respectively.Static headspace gas chromatography-mass spectrometry was used to detect the volatile compounds.The main results were following: 37 compounds were detected from the C.linmon leaves,including (+)-limonene,sabinene and myrcene showed relatively higher content.The content of volatile compounds had changed significantly after D.citri feeding stress,including increase terpenoids,aldehydes,alcohols and decreased esters.Sabenene,linalool,(+)-citronellal and nerol increased by 2.1,2.9,7.8 and 3.2 times after 96 h stress,respectively,while the content of α-caryophyllene decreased by 1.9 times.Some other compounds showed unobvious changes,such as (+)-limonene,β-bisabolene and trans -α-bergamotene.Three volatile compounds emerged after D.citri feeding stress,including rosefuranepoxide,geraniol and thymol methyl ether.Pearson correlation analysis showed that the content of 9 substances,such as sabenene,β-pinene,methylhepenone,myrcene and phellandrene,had extremely significant positive correlation with D.citri stress time ( P <0.01) and 11 substances,such as (R )-α-pinene,camphene,terpilene and γ-terpinene,showed significant positive correlation with the stress time ( P <0.05).While significant negative correlation between the content of Methyl N-methylanthranilate and the D.citri stress time ( P <0.01).The further cluster analysis and heat map analysis showed that the samples of different treatment had significant differences.Most of the volatile compounds in C.limon leaves showed a rising trend,especially after the stress of 48,72 and 96 h,when the content of the material increased significantly.The results provided a theoretical basis for understanding the metabolism of citrus response to biotic stress such as D.citri and its biological control.