Microclimatic parameters affect Cladosporium rot development and berry quality in table grapes

Cladosporium cladosporioides is an emerging pathogenic fungus that causes Cladosporium rot in postharvest table grapes(Vitis vinifera). However,studies investigating the infection process of C. cladosporioides are lacking. Therefore, this study aimed to elucidate the infection process by investigating the influence of microclimatic parameters(temperature, wetness and fungal age) in C. cladosporioides pathogenesis, activities of grape defense-related enzymes and grape quality during the infection. C. cladosporioides effectively infects grapes by developing distinct colonies on the artificial wounds and berry surfaces, completing its life cycle within 48 h. The C. cladosporioides disease incidence optimally occurred at 20 ℃ and 25 ℃. Wetness played an influential role in the infectivity of C. cladosporioides and 7-day-old C. cladosporioides resulted in the most serious disease incidence of table grapes. As a result of infection, the quality of grapes was affected, including berry weight, p H, titratable acidity(TA), total soluble solids(TSS), and ascorbic acid level. This infection also induced defense-related enzymes, including polyphenoloxidase(PPO), peroxidase(POD), phenylalanine ammonialyase(PAL), and catalase(CAT), at certain times. The findings of this study demonstrated that Cladosporium rot development depended on the microclimatic parameters of grapes, significantly affected the grape quality and induced grape's defense-related enzymes.

Current Situation of Table Grape Industry in Henan Province and Development Recommendations

Through the investigation of the current production situation,regional distribution,variety structure,production organization and existing problems of table grapes in Henan Province,this paper conducted an in-depth analysis on the advantages and disadvantages of the development of table grapes industry in Henan Province.In view of the current problems and development trend,it came up with some pertinent recommendations,including transforming the concept of cultivation,adhering to the principle of"high-quality varieties,standardized cultivation,mechanized management,large-scale operation,and diversified market",strengthening brand building,and promote the integrated development of the primary,secondary and tertiary industries,so as to promote the change of table grape industry in Henan Province from"quantitative scale model"to"quality benefit model",and promote its sustainable and high-quality development.

The use of widely targeted metabolite profiling to reveal the senescence changes in postharvest 'Red Globe'(Vitis vinifera) grape berries

Changes in the metabolites of table grapes(Vitis vinifera) reportedly occur during postharvest senescence. The aim of this study was to determine the metabolomic differences in postharvest table grapes(‘Red Globe’) after being subjected to different senescence periods. To this end, we used widely targeted metabolomics based on ultra-performance liquid chromatography and tandem mass spectrometry. A total of 135 differential metabolites were identified. During postharvest senescence, the levels of most differential flavonoids(e.g., pelargonidin 3-O-glucoside, quercetin-3-O-glucoside, and cyanidin 3-O-glucoside) and L-aspartic acid decreased, while the levels of phenolic acids(e.g., trans-4-hydroxycinnamic acid methyl ester) and pantothenol increased. During early and late senescence, the levels of most differential lipids, especially LysoPC, as well as those of nucleotides and their derivatives, such as uridine, decreased and increased, respectively. Collectively, the findings of this study provide fundamental insights into the reasonable control of table grape fruit postharvest senescence and lay a solid foundation for further research.

Genetic Stability of Cryopreserved Grapevine （Wtis vinifera L.） Genome by Vitrification Method

Grapevine （Vitis spp.） is an economically important fruit crop worldwide. In Mexico, Sonora State leads the table grape production and exportation to international markets. In this regard, it is important to preserve the grape varieties during long time without phenotypical or genotypical changes. Cryopreservation is a good alternative, although it very often can induce changes in genome and phenotype. In this study, grapevine cv. ＂Flame Seedless＂ axillary buds were cryoprcserved by vitrification using the plant vitrification solution 2 （PVS2） and stored in liquid nitrogen （LN） for one hour, one week and one month, respectively. Genetic stability of buds cryopreserved under all treatments was evaluated using inter-simple sequence repeats （ISSR） markers. Ten ISSR primers were evaluated, but only two primers were possible to amplify distinct and reproducible bands with sizes between 300 bp and 2,000 bp. Different ISSR fragment patterns were recorded in cryopreserved buds as compared with control. These results suggest that cryopreservation by LN and vitrification-cryopreservation affect genetic stability in grapevine.