Ruangnam Saowalak, Wanchana Samart, Phoka Nongnat, Saeansuk Chatree, Mahatheeranont Sugunya, de Hoop Simon Jan, Toojinda Theerayut, Vanavichit Apichart, Arikit Siwaret
Faculty of Agriculture at Kamphaeng Saen, Kasetsart University Kamphaeng Saen Campus, Nakhon Pathom, 73140, Thailand.
Hortigenetics Research (S.E. Asia) Limited, Suphanburi, 72190, Thailand.
Theor Appl Genet. 2017 Dec;130(12):2557-2565. doi: 10.1007/s00122-017-2976-3. Epub 2017 Sep 8.
The gene conferring a "pandan-like" aroma of winter melon was identified. The sequence variation (804-bp deletion) found in the gene was used as the target for functional marker development. Winter melon (Benincasa hispida), a member of the Cucurbitaceae family, is a commonly consumed vegetable in Asian countries that is popular for its nutritional and medicinal value. A "pandan-like" aroma, which is economically important in crops including rice and soybean, is rarely found in most commercial varieties of winter melon, but is present in some landraces. This aroma is a value-added potential trait in breeding winter melon with a higher economic value. In this study, we confirmed that the aroma of winter melon is due to the potent volatile compound 2-acetyl-1-pyrroline (2AP) as previously identified in other plants. Based on an analysis of public transcriptome data, BhAMADH encoding an aminoaldehyde dehydrogenase (AMADH) was identified as a candidate gene conferring aroma of winter melon. A sequence comparison of BhAMADH between the aromatic and non-aromatic accessions revealed an 804-bp deletion encompassing exons 11-13 in the aromatic accession. The deletion caused several premature stop codons and could result in a truncated protein with a length of only 208 amino acids compared with 503 amino acids in the normal protein. A functional marker was successfully developed based on the 804-bp deletion and validated in 237 F progenies. A perfect association of the marker genotypes and aroma phenotypes indicates that BhAMADH is the major gene conferring the aroma. The recently developed functional marker could be efficiently used in breeding programs for the aroma trait in winter melon.
鉴定出了赋予冬瓜“类似香兰素”香气的基因。该基因中发现的序列变异（804bp缺失）被用作功能标记开发的靶点。冬瓜（Benincasa hispida）是葫芦科的一员，是亚洲国家常见的食用蔬菜，因其营养价值和药用价值而受到欢迎。“类似香兰素”的香气在包括水稻和大豆在内的作物中具有重要经济意义，在大多数冬瓜商业品种中很少见，但在一些地方品种中存在。这种香气是培育具有更高经济价值冬瓜的一个具有增值潜力的性状。在本研究中，我们证实冬瓜的香气是由于一种强效挥发性化合物2-乙酰基-1-吡咯啉（2AP），正如之前在其他植物中所鉴定的那样。基于对公共转录组数据的分析，编码氨基醛脱氢酶（AMADH）的BhAMADH被鉴定为赋予冬瓜香气的候选基因。芳香型和非芳香型种质之间BhAMADH的序列比较显示，芳香型种质中存在一个804bp的缺失，涵盖外显子11-13。该缺失导致了几个提前终止密码子，并可能导致产生一个截短的蛋白质，其长度仅为208个氨基酸，而正常蛋白质为503个氨基酸。基于804bp缺失成功开发了一个功能标记，并在237个F后代中进行了验证。标记基因型与香气表型的完美关联表明BhAMADH是赋予香气的主要基因。最近开发的功能标记可有效地用于冬瓜香气性状的育种计划。
