Shan Nan, Gan Zengyu, Nie Jing, Liu Huan, Wang Zhenyu, Sui Xiaolei
Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China.
College of Agronomy, Jiangxi Agricultural University, Nanchang 330045, China.
Foods. 2020 Mar 5;9(3):294. doi: 10.3390/foods9030294.
Bagging is widely practiced to produce high quality and unblemished fruit; however, little is currently known about the effect of bagging on flavor and nutritional quality of cucumber fruits. Here we determined the influence of bagging on fruit quality of cucumber ( L.) using three genotypes from different geographic groups. Exocarp chlorophyll and carotenoid levels were significantly decreased by bagging, accompanied by color change. Ascorbate content in bagged fruits decreased to some extent, while contents of soluble sugars, starch, and cellulose were comparable with those of control fruits. Compositions related to fruit flavor quality could be enhanced largely through bagging treatment, with elevation of the relative proportion of C aldehyde, as well as ()-2,6-nonadienal/()-2-nonenal ratio, and linoleic/α-linolenic acid ratio. Lipoxygenase and hydroperoxide lyase, two key enzymes in the production of volatiles, displayed distinctive transcript expression patterns and trends in changes of enzymatic activity in the bagged fruits of different genotypes. Overall, this study assesses the information on changing characteristics of fruit volatile composition and nutritional quality among different cucumber genotypes after bagging treatment. Results of this study would contribute to providing reference for mechanism study and cultivation conditions to improve cucumber fruit flavor to a considerable degree.
套袋广泛应用于生产高品质、无瑕疵的果实；然而，目前对于套袋对黄瓜果实风味和营养品质的影响知之甚少。在此，我们使用来自不同地理群体的三个基因型来确定套袋对黄瓜（L.）果实品质的影响。套袋显著降低了外果皮叶绿素和类胡萝卜素水平，并伴随着颜色变化。套袋果实中的抗坏血酸含量有所下降，而可溶性糖、淀粉和纤维素的含量与对照果实相当。与果实风味品质相关的成分可通过套袋处理得到很大程度的提升，包括C醛的相对比例以及（）-2,6-壬二烯醛/（）-2-壬烯醛的比例和亚油酸/α-亚麻酸的比例升高。脂氧合酶和氢过氧化物裂解酶是挥发性物质产生过程中的两种关键酶，在不同基因型的套袋果实中表现出不同的酶活性变化模式和趋势。总体而言，本研究评估了套袋处理后不同黄瓜基因型果实挥发性成分和营养品质变化特征的信息。本研究结果将有助于为改善黄瓜果实风味的机制研究和栽培条件提供相当程度的参考。
