| 摘要: |
| 为挖掘我国特有的果实香气浓郁的梨资源,弄清其果实芳香成分及含量,并进而研究它们在梨果实中的代谢与调节机制。采用气相色谱质谱联用(GC-MS)技术,分析了我国部分秋子梨品种果实的香气成分,在基础上,以挖掘出的‘南果梨’为试材,采用RACE技术克隆了与其果实特异香气成分生物合成相关的α-法尼烯合成酶基因(PuFS),并采用半定量PCR(RT-PCR)技术分析了该基因在其果实不同发育时期和不同部位的时空表达规律。结果表明:‘荣香’、‘龙香’、‘香水’和‘晚香’的主要香气成分为醛类物质,‘南果’、‘大南果’和‘寒香’梨主要香气成分为酯类物质。在‘南果’梨中还检测出了高含量的α-法尼烯,而在其他品种中α-法尼烯相对含量较低或未检测到,这可能是‘南国’梨具有浓郁香气的主要原因;随着果实的成熟,PuFS基因在‘南果梨’果皮中的表达量呈逐渐下降的趋势,绿熟期表达量最高,商熟期表达量开始降低,完熟期表达量非常弱。而PuFS在3个时期果肉中的表达量均很弱,且差异不明显。总体上,PuFS基因在绿熟期的表达量高于商熟期和完熟期,在果皮中的表达量显著高于果肉。 |
| 关键词: 南国梨 果实香气 α-法尼烯合成酶基因 克隆与表达 |
| DOI：10.11841/j.issn.1007-4333.2015.06.11 |
| 投稿时间：2015-05-11 |
| 基金项目:江苏省林业三新工程项目(LYSX(2014)43) |
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| Cloning and expression analysis of PuFS gene related to aromatic constituents biosynthesis in Pyrus ussuriensis ‘Nanguo’ fruit |
|
FENG Li-guo1, BA Jin-lei1,2, WEI Jun1, MENG Xiang-yi1, SHENG Li-xia1
|
| (1.College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, China;2.Institute of Vegetable Science, Bureau of Agriculture and Animal Husbandry of Chengde, Chengde 067000, China) |
| Abstract: |
| In order to find out the specific pear aroma resources,discover the compositions and contents of their fruit aroma,and study the metabolism and the regulation mechanism of the fragrance substance in pear fruit,analysis of fruit aroma components of 7 Pyrus ussuriensis cultivars were carried out by GC-MS firstly.P.ussuriensis ‘Nanguo’ was then excavated as a specific test material for rich in fruit aroma.The full sequence of α -Farnesene synthase gene (PuFS),which is related to the biosynthesis of special aromatic compounds in ‘Nanguo’ pear was cloned by RACE,and the expression patterns of PuFS gene in different developmental stages and different organs were analyzed by RT-PCR.The results showed that:Aldehydes were the main floral components of pear ‘Rong xiang’,‘Long xiang’,‘Xiang shui’ and ‘Wan xiang’ .Esters were the main floral components of pear ‘Nan guo’,‘Da nan guo’ and ‘Han xiang’;High level of α- farnesene was also detected in pear ‘Nan guo’,while it waslow or undetectable in other pear cultivars.It might be the main reason why ‘Nanguo’ pear's aroma is very rich;We also found that the expression level of PuFS gene was gradually declined with fruit ripening in pear pericarp of pear ‘Nan guo’ and it reached the highest level in green stage,started to dropduring commercial stage,and then decreased rapidly in ripe stage.The expression levels of PuFS gene in pear sarcocarp of three developmental stages are all low and having no obvious difference.To summarize,the expression level of PuFS gene in green stage was higher than in the other two stages,and its level in the pericarp was significantly higher than in the sarcocarp. |
| Key words: Pyrus ussuriensis ‘Nanguo’ fruit aroma constituents α -farnesene synthase cloning and gene expression |
