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The objective of this study is to research the genetic diversity of the ‘ Zuijinxiang ’ grape and its mutant breeding F1 plants, we screened the excellent mutant plants with potential breeding value. 50 mutated single plants obtained from 137Cs-γ irradiated ‘Zuijinxiang’ grape seeds were used as research objects, and SCoT molecular marker technology was used for genetic diversity and variation analysis, and clustering research was carried out. The results showed that: (1) 36 SCoT primers produced abundant polymorphisms, and the amplification results showed obvious bright bands, and the amplification efficiency and polymorphism rate were 100%. (2) A total of 221 bands were amplified by 36 primers, of which 175 were rich in polymorphism, the average polymorphic percentage was 80.3%, and the average genetic similarity coefficient was 0.916. (3) The number of observed alleles (Na) ranged from 4 to 8, with an average of 6.1389; the number of effective alleles (Ne) ranged from 1.2772 to 5.6322 with an average of 3.5968; the desired heterozygosity (He) The range is from 0.2192 to 0.8344, the average is 0.6965; the observed heterozygosity (Ho) ranges from 0.1656 to 0.7808 with an average of 0.3035; the Nei’s gene diversity index (H) ranges from 0.2170 to 0.8224 with an average of 0.6863; Shannon-Wiener The index (I) ranges from 0.5186 to 1.8597 with an average of 1.4517. (4) UPGMA clustering of 51 materials showed that the test materials could be divided into three groups when the genetic distance was 0.856. The experiment shows that the genetic diversity of the ‘Zuijinxiang’ radiation variation germplasm resources is rich. In addition, SCoT molecular marker technology can distinguish the materials with close genetic distance, and can be used for early identification techniques of grape mutant materials. This study provides a theoretical basis for the development of excellent mutant germplasm of ‘Zuijinxiang’ grapes.

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Paid search advertising is a critical source of traffic for sellers on e-commerce platforms. As the mobile Internet gains prominence as the main channel for reaching consumers, sellers need to know how to select and bid on keywords in online versus mobile search settings. This study compares the differential effects of paid search keywords in online and mobile settings on both direct and indirect sales, along with the moderating roles of keyword specificity and keyword cost. Two field studies and two lab experiments consistently show that a paid keyword in a mobile setting can prompt higher direct sales than it does in an online setting, but it generates lower indirect sales in general. Moreover, while keyword cost attenuates this positive relationship between mobile searching and direct sales, keyword specificity and keyword cost attenuate this negative relationship between mobile searching and indirect sales. Empirical evidence also reveals the sales and return on investment of paid search keywords in mobile and online settings. This study enriches previous literature by detailing new insights into the distinct settings of mobile and online search advertising.Keywords Mobile . Online . Paid search advertising . Keyword specificity . Keyword cost Paid search advertising is a critical source of traffic for sellers on e-commerce platforms such as Amazon, eBay, and Taobao, enabling them to connect with consumers who seek product information (Fang et al. 2015;Lu and Zhao 2014). This vital marketing tool accounts for 44.2% of digital advertising spending (eMarketer 2017). To insert their advertisements onto the platforms, sellers bid on keywords that they predict will match consumers' search queries. Many studies thus suggest keyword bidding strategies (Du et al. 2017;Gerstmeier et al. 2009) and analyze the effects of different keyword characteristics (e.g., brand-related, popularity) on click-through rates, conversions, and product sales (Ghose and Yang 2009;Lu and Zhao 2014;Rutz et al. 2012). Despite this extensive literature (Table 1), most scholars investigate paid search keywords in online searching through personal computers (PCs), rather than mobile searching through mobile devices.Yet the vast penetration of mobile devices indicates that mobile Internet is taking over as a dominant channel for sellers to reach consumers (Lamberton and Stephen 2016). Mobile and online accesses are essentially different since ( 1) mobile devices are easier access and spatially and temporally flexible (Xu et al. 2017); (2) mobile Internet is operated by a directtouch rather than a mouse-driven interface (Shen et al. 2016); and (3) mobile devices provide smaller screen size and less display space (Ghose and Han 2011). Noting these differences, several studies have investigated both mobile and online advertising. For example, Han et al. (2013) identified cross-channel synergies between online and mobile advertising, Xu et al. (2017) revealed the effects of tablets on consumer purchases through PC and mobile devices, and de Haan et...

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Shading is a practical measure to reduce the heat stress to grape trees in the summer. However, inappropriate shading will cause the reduction in leaf photosynthesis and consequently the retardation of growth for the plants or the loss of fruit yield and quality for the mature grape trees. In this study we have used 1-year-old ‘YinHong’ grape plants growing under different levels of shading, ranging from full sunlight 0% to 80% reduction, to investigate their growth, physiological and biochemical responses. The results show that shading rate =45% did not significantly affect grape growth. Shading over 45% reduction of the full sunlight, the growth of the grape plants were started to be inhibited. In addition, soluble protein content, the activities of catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD), chlorophyll content, net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentration (Ci), transpiration rate (Tr), PSII photochemical efficiency (Fv/Fm), PSII potential activity1(Fv/Fo) and photochemical quenching (qP) were decreased, whereas free proline, malondialdehyde (MDA) content, the non-photochemical quenching coefficient (qN) and the ratio of the palisade/spongy tissue were gradually increased. In particular, significant changes in plant growth, photosynthetic and the other physiological and biochemical characteristics were observed under a strong shading.

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