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Background and Aims: Bunch bagging is a grapevine canopy management strategy to protect bunches from light, heat stress and disease pressure. The aim of this study was to unveil the effects of timing and duration of bunch bagging on grape volatile organic compounds (VOCs) at the transcriptomic and metabolic levels. Methods and Results: Seven bunch bagging treatments of varying timing and duration were implemented with Cabernet Sauvignon grapes. Regardless of timing and duration, bagging significantly reduced nerol, benzaldehyde, benzeneacetaldehyde and p‐cymene, and increased the concentration of phenol and 3,5‐dimethylbenzaldehyde. The decrease of nerol by bagging was associated with the down‐regulation of the gene encoding glycosyltransferase14 at veraison. Bagging and re‐exposing bunches at the preharvest stage inhibited and benefited the accumulation of C6 alcohols. Furthermore, we infer that the higher concentration of total benzenoids in all bagged berries was due to the down‐regulated expression of phenylpropanoid biosynthesis genes. The concentration of the dominant norisoprenoid, β‐damascenone, was not impacted by bunch bagging from veraison to harvest and was increased by bagging from veraison to post‐veraison. All other treatments, however, reduced this compound, which was due to a lower concentration of β‐carotene and lutein, and the down‐regulation of VviCCD4a and VviCCD4b. Conclusions: Both timing and duration of bunch bagging can affect biosynthesis and accumulation of VOCs. Significance of the Study: Insights from this study provide new knowledge on bunch bagging, as well as information regarding the sensitivity of VOCs to light and the timing of light exposure during grape ripening. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we established and characterized a cell line derived from the kidney of black carp (Mylopharyngodon piceus), which is an important freshwater aquaculture species. The cell line was designated as MPK and subcultured for more than 70 passages in DMEM medium containing 10% fetal bovine serum (FBS) at 28°C. MPK had a modal diploid chromosome number of 48. Moreover, a transient MPK transfection efficiency was up to 18% using a green fluorescent protein plasmid by a modified electroporation. In addition, the MPK cells showed susceptibility to spring viremia of carp virus (SVCV), as demonstrated by the presence of severe cytopathic effects (CPEs) and increased viral RNA. Unexpectedly, the MPK cells expressed pluripotency‐associated genes such as nanog, oct4 and vasa, indicating that these are possibly adult stem cells. Taken together, we have established a stable cell line from kidney that may potentially be utilized as an in vitro platform for genetic modifications and host–pathogen analysis in black carp. [ABSTRACT FROM AUTHOR]

Background and Aims: Anthocyanins are a group of important phenolic compounds which are responsible for the colour of red grape and wine. This study aimed to confirm the existence of pelargonidin-3- O-glucoside in Vitis vinifera grape berry skins. Methods and Results: The anthocyanin profiles in the berry skins of Cabernet Sauvignon and Pinot Noir were analysed by high performance liquid chromatography - electronic spray ionization - tandem mass spectrometry. Besides 17 anthocyanins that are commonly determined in the berries of these two varieties, pelargonidin-3- O-glucoside was also detected at trace levels. Conclusions: The mass-spectrometry evidence confirmed the existence of pelargonidin-3- O-glucoside in non-teinturier V. vinifera grapes. Significance of the Study: This finding will be beneficial for the further understanding of anthocyanin profile and its biosynthesis in grape berries. [ABSTRACT FROM AUTHOR]

Background and Aims: In an effort to protect the development of the icewine production industry, this study aimed to find indicators to distinguish between authentic and non-authentic icewines. Methods and Results: Fully ripened berries were used to prepare three types of high-sugar grape juices: naturally frozen juice, refrigerator-frozen juice and concentrated juice. The content of phenolic acids and flavan-3-ols in the samples before and after fermentation was assayed. Significant differences were found in the individual level of most phenolic acids and flavan-3-ols except chlorogenic acid, sinapic acid and (−)-epicatechin among the three types of high-sugar juices. At the end of fermentation, there were significant differences in the wines, not attributable to the influence of yeasts. Conclusions: Vanillic acid, caffeic acid, (−)-epigallocatechin gallate, gentisic acid and syringic acid may be used as indicators of authentic icewine. Significance of the Study: This work provides a basis for distinguishing authentic icewine and controlling icewine quality. [ABSTRACT FROM AUTHOR]

Background and Aims: Sugar is a main contributor to the quality of grape berries, but little is known about the characteristics of sugar metabolism in Chinese wild grapes. Here, enzymes related to sugar metabolism were investigated in berries of both Shang-24 ( Vitis quinguangularis Rehd), a wild grape native to China, and Cabernet Sauvignon ( V. vinifera L.). Methods and Results: Analyses using high performance liquid chromatography and spectrophotometer showed that Shang-24 contained lower levels of glucose and fructose, compared with Cabernet Sauvignon, but had higher activities of enzymes related to sugar hydrolysis, particularly soluble acid invertase (SAI) and β-amylase. Analyses of enzyme kinetics, enzyme-linked immunosorbent assay and Western blot revealed that SAI and β-amylase in Shang-24 had low Km values and that high levels of both enzymes were present. Furthermore, a novel peptide of SAI of 105 kDa was detected in Shang-24 along with a peptide of 60 kDa that also was present in Cabernet Sauvignon. Conclusions: It is thus suggested that biochemical characteristics of SAI and β-amylase in Shang-24 differ from those in Cabernet Sauvignon, and the novel peptide may be related to high activity of SAI in Shang-24. Significance of the Study: These data provide an essential basis for further study of the genetic regulation of sugar and its metabolism in grape berries. [ABSTRACT FROM AUTHOR]

The Chinese native rice cultivar 'Maowangu' expresses a high level of resistance to many races of rice blast (Pyricularia grisea) collected from North China and Japan. `Maowangu' was crossed with 10 Japanese differential cultivars and the susceptible Chinese cultivar 'Liji- angxintuanheigu' (LTH). Allelism tests were conducted in the F2 populations with rice blast races. The resistance of `Maowangu' was governed by two dominant genes which were non-allelic to the resistance genes at seven loci: Pi-a, Pi-i, Pi-k, Pi-z, Pi-ta, Pi-b, and Pi-t. To identify the two resistance genes, two F3 lines of 'Shin 2/Maowangu' segregating 3R:1S were selected for linkage tests in 1994. One was linked to marker genes C and Amp-3 on chromosome 6 with recombination frequencies of 35.8±6.4% and 42.1 ± 6.2%, respectively, and the other to Amp-1 on chromosome 2 with a recombination frequency of 37.6±6.0%. To confirm these results, two F3 lines of `LTH/Maowangu' were selected for linkage tests in 1995. The one was linked to Amp-3, and other was linked to Amp-1, with recombination frequencies of 36.9 ± 3.1% and 34.3 ± 3.2%, respectively. The two genes on chromosomes 6 and 2 were designated Pi13(t) and Pi14(t), respectively. [ABSTRACT FROM AUTHOR]