Effects of trellis system and berry thinning intensity on vine performance and quality composition of two table grape cultivars under protected cultivation in northern China

•Fruiting capacity, budding rate and canopy characters differed between pergola and SAYM trellis.•Sugar compositions and skin total anthocyanins maintained higher in berries from SAYM.•Highly thinned clusters showed remarkable effects on most quality attributes, while moderate and light thinning intensity exerted similar effects.•Cultivar played a major role in a few attributes.