36份桃品种资源果实挥发性成分遗传多样性分析

Genetic Diversity of Fruit Volatile Compounds in 36 Peach Varieties

为探究桃资源果实挥发性成分遗传多样性,以36份桃品种资源果实为试材,采用顶空固相微萃取结合气相色谱质谱联用技术检测样品挥发性物质,并进行方差分析、变异系数、相关性分析、主成分分析(PCA,principal component analysis)和偏最小二乘-判别分析(PLS-DA,partial least squares-discriminant analysis)。结果表明,在36份桃品种资源中共检测到77种挥发性物质,包括萜类、醛类、酯类、内酯类、醇类和酮类等。挥发性成分的变异系数范围为18%~390%,说明资源具有丰富的香气表型多样性。相关性分析结果显示,性状间呈显著相关和极显著相关性的分别有11对和10对,其中果肉颜色、品种类型、粘离核、果实质地与香气物质含量相关。PCA分析可以明显区分白肉桃和黄肉桃。以变量投影重要性(VIP,variable importance in projection)>1,P<0.05为标准,筛选到9种区分黄肉桃和白肉桃的特征挥发性物质,其中茶螺烷的VIP值最高。

To investigate the genetic diversity of volatile compounds in peach fruits,36 peach varieties were analyzed by headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry,followed by ANOVA,coefficient of variation,correlation analysis,principal component analysis and partial least squares-discriminant analysis.The results showed that 77 volatile compounds were detected in 36 peach varieties,including terpenoids,aldehydes,esters,lactones,alcohols and ketones.In addition,the coefficient of variation in volatile compounds of 36 peach varieties ranged from 18%to 390%,indicating that the enrichment of volatile organic compounds diversity in different peach varieties.Based on the correlation analysis,11 and 10 pairwise-traits were found with correlation and significant correlation,respectively,among which several traits including flesh color,variety type,stone adherence to flesh and flesh texture were correlated with aroma substance content.PCA analysis could clarify white-fleshed and yellow-fleshed peaches.Using variable importance in projection(VIP)>1 and P<0.05 as criteria,nine characteristic volatile substances were identified and distinguishable in yellow-fleshed peaches from white-fleshed peaches,among which theaspirane was found with the highest VIP.