油茶蓝翅天牛为害与寄主油茶内营养物质和次生物质含量的关系

Interrelation between Chreonoma atritarsis Pic. and the nutrient content and secondary metabolites of the host plant Camellia oleifera

【目的】揭示油茶蓝翅天牛ChreonomaatritarsisPic.发生与寄主枝条营养物质及次生物质含量之间的相互关系,为蓝翅天牛在油茶林中的发生监测预警提供基础依据。【方法】采用五点法对蓝翅天牛在油茶幼龄林和壮龄林中的为害情况进行了调查;采用烘干称重法、蒽酮比色法、3,5-二硝基水杨酸法(DNS法)和考马斯亮蓝G-250等方法分别测定不同林龄内的油茶枝条含水量,枝条可溶性总糖、还原糖、可溶性蛋白等主要营养物质的含量,以及总酚、缩合单宁和黄酮等次生物质的含量,并进一步分析为害情况与各物质含量间的相关性。【结果】林间调查结果表明,油茶蓝翅天牛能够为害幼龄油茶林,且在幼龄林中喜为害枝高≤50cm、直径>1cm枝条,尤以直径1-2cm枝条受害最重;壮龄油茶林中在枝高>50 cm枝条、直径>1 cm的枝条上为害较重,尤以直径>2 cm枝条受害最重。室内研究结果揭示了油茶枝条营养物质及次生物质含量由高到低依次为可溶性总糖、还原糖、总酚、缩合单宁、可溶性蛋白和黄酮。其中,枝条韧皮部和木质部中各物质的含量存在显著差异。油茶蓝翅天牛在幼龄林内的选择为害行为和油茶枝条的还原糖与可溶性总糖之比呈显著负相关,和可溶性蛋白含量呈显著正相关;在壮龄油茶林内选择为害行为与枝条的总酚、缩合单宁含量呈显著负相关。【结论】油茶蓝翅天牛对油茶枝条的为害选择与枝条内的可溶性蛋白含量存在显著正相关关系,与还原糖与可溶性总糖含量之比、总酚含量及缩合单宁含量存在显著负相关关系。因此在林间栽培油茶植株过程中应加强对相应树龄及直径枝条植株上蓝翅天牛发生的监测预警。

[Objectives]To determine the correlation between the occurrence of Chreonoma atritarsis and the nutrient and secondary metabolite content of its host plant,the oil tree,Camellia oleifera.[Methods]The five-point method was used to investigate C.atritarsis damage to young and adult oil trees.The water content and the total soluble sugar,reducing sugar,soluble protein,and the main secondary metabolites;i.e.total phenols,condensed tannins and flavonoids,among branches of different ages were quantified by oven drying,anthronecolorimetry,the 3,5-dinitrosaliculic acid method(DNS colorimetry),and staining with Coomassie brilliant blue G250.The correlation between the amount of damage and the content of each substance was then analysed statistically.[Results]Forest survey results indicate that most C.atritarsis damage to young oil tea trees was on branches at a height of≤50 cm and a diameter of>1 cm,especially those with a diameter of 1-2 cm.In adult trees,branches at a height of>50 cm and a diameter of>1 cm sustained more damage,especially those with a diameter of>2 cm.The results of laboratory studies revealed that the most abundant nutrient and secondary metabolite contents of oil tea trees were,in descending order;soluble total sugar,reducing sugar,total phenols,condensed tannins,soluble protein and flavonoids.Among these,there was a significant difference in the content of each substance in the phloem and xylem of branches.The damage inflicted by C.atritarsis on young trees was negatively correlated with the ratio of reducing sugar to soluble total sugar,and positively correlated with soluble protein content.In adult trees,damage was negatively correlated with total phenols and condensed tannin content.[Conclusion]There was a significant,positive correlation between the amount of C.atritarsis damage and soluble protein content in oil tree branches,and a significant,negative correlation between the amount of C.atritarsis damage and the ratio of reducing sugar to soluble total sugar,total phenols and condensed tannin content.Monitoring for C.atritarsis should take into consideration both tree age and branch diameter.These results facilitate more effective monitoring,and obtaining early warning of outbreaks,of C.atritarsis.