Analysis of the aromatic compounds of four tetraploid muscat flavor grapes and their diploid parents

TAN Wei; TANG Xiaoping; DONG Zhigang; LI Xiaomei

doi:10.13925/j.cnki.gsxb.20160218

Abstract：[Objective] In recent years,breeders and consumers pay more and more attention to tetraploid grapes because of their big berry size with less seeds and their high yields.The researchers at the Pomology Institute,Shanxi Academny of Agricultural Science bred three tetraploid grape varieties from colchicine treated hybrid seeds,including ‘Zaoheibao’ ‘Qiuheibao’ and ‘Wanheibao’ with a rose fragrance.While representing one of the inherent properties of grapes,there has been no research on the analysis of the aroma composition between tetraploid and diploid grapes.In order to provide a theoretical basis for further understanding of tetraploid grapes,the aromatic compounds of fruits during their ripening period,we analyzed four tetraploid table grapes with muscat flavor including ‘Zaoheibao’ ‘Qiuheibao’ ‘Wanheibao’ and ‘Tetraploid Muscat Hamburg’ as well as their diploid parents including ‘Guibao’ ‘Zaomeiguixiang’ ‘Christmas Rose’ and ‘Muscat Hamburg’.[Methods]The berries were collected during August-September 2013 from eight grape vines grown in the breeding vineyards of the Pomology Institute,Shanxi Academy of Agricultural Science in Taigu,China.The samples were frozen using liquid nitrogen and stored in an ultra-low temperature freezer.Then the aromatic compounds of the samples were determined in the College of Horticulture Science and Engineering,Shandong Agricultural University in Taian,China,using a solid phase micro-extraction (SPME) and gas chromatograghy-mass spectrometry (GC/MS).According to the mass spectrometer ion scanning map,the aromatic compounds were quantitatively analyzed by using the area normalization method,taking the average score of 3 repeated tests as the basis for the relative content of the aroma component.All collected data were analyzed using SPSS 13.0 and Excel software for statistical analysis.[Results] There were significant differences in types and relative content of the aromatic components among the eight grape varieties.There were primarily seven types of aromatic components in grapes,including alcohol,aldehyde,ketone,ester,olefins,acid and others.There were one or two types of acid in ‘ Zaoheibao’ and ‘ Zaomeiguixiang’,respectively,while there was no acid in the other six grape varieties;in addition,there was no ester in the ‘Zaoheibao’.The same aromatic components among the eight grapes were identified as twelve different types,including three types of alcohols,five types of aldehydes,two types of ketone and two types of olefin.The major aromatic compounds found in the eight grape varieties are aldehydes,with a relative content of 56.49％-81.63％,especially 2-hexene aldehyde and hexaldehyde with a green leaf flavor and fruity scent,which were the two richest compounds.The 2-hexene aldehyde was the first rich compound identified,with a relative content of 34.40％-49.81％,which was the richest in ‘Qiuheibao’ and ‘Qiuhong’ as tetraploid and diploid grapes,respectively.There were no significant differences in the relative content of 2-hexene aldehyde between ‘ Tetraploid Muscat Hamburg’ and ‘ Muscat Hamburg’;but the relative content in ‘ Zaoheibao’ and ‘ Wanheibao’ were lower than that in their diploid parents,while that in ‘Qiuheibao’ was between its parents.Aldehyde was the second rich compound identified,with a relative content of 16.28％-28.43％,which was richest in ‘Wanheibao’ and ‘Qiuhong’ as tetraploid and diploid grapes,respectively.‘Tetraploid Muscat Hamburg’ had a significantly higher aldehyde content than ‘Muscat Hamburg’ and the content in ‘Zaoheibao’ was lower than that in its father ‘Zaomeiguixiang’;the ones in ‘Qiuheibao’ and ‘Wanheibao’ were significantly higher than that in its mother ‘ Guibao’,yet it was lower in ‘ Qiuheibao’ which was lower than that in its father ‘ Qiuhong’.Terpenoid compounds and their content are closely related to the unique fragrance of roses in Eurasian grapes,especially in the free form of monoterpene.As shown in the results,except for ‘ Qiuhong’,the rest of the seven rose-fragrant grapes had a high relative content of terpene alcohols (7.24％-28.60％) and all contained linalool and nerol,which with an aroma of rose wood,green sweet orange fragrance flowers and roses,respectively.And except for ‘Guibao’ among the seven rose fragrance grapes,the rest of the six grapes contained geraniol and citronellol,which has an aroma of light sweet rose,green grass and sweet rose,respectively.The relative content of linalool and geraniol was 4.14％-25.23％ in the seven grapes,of which the order from high to low in the four tetraploid grapes was:‘Zaoheibao’ ‘Tetraploid Muscat Hamburg’ ‘Wanheibao’,and ‘Qiuheibao’,while that in the diploid grapes was ‘Guibao’ ‘Muscat Hamburg’ and ‘Zaomeiguixiang’.The relative content of terpene alcohol in ‘Tetraploid Muscat Hamburg’ was only 3.94％ higher than that in ‘Muscat Hamburg’,while that in ‘Zaoheibao’ was 2.07％,20.21％ higher than that in its parents ‘Guibao’ and ‘Zaomeiguixiang’,respectively.And it was 13.21％ and 7.87％ lower in ‘Wanheibao’ and ‘Qiuheibao’ than that in their parents ‘Guibao’.[Conclusion] Linalool and geraniol with the fragrance of the rose wood and light sweet rose fragrance respectively played the most important role in fruit aroma of the seven grapes with a muscat flavor.According to the results,the relative content of the major flagrant substances was not doubled after doubling the chromosome of the diploid rose-flagrant grapes.The aroma rich degree of the tetraploid grape was related to the strength of the parental rose fragrance.The main fruit aromatic substance found in the eight grapes was C6 aldehyde.