Influences of different light filter film bags on berry quality in‘Red Globe'

【Objective】This experiment studied the effects of light quality provided by light filter films and shading on berry quality in Vitis vinifera L.‘Red Globe'.【Method】The experimental materials were the fruit of‘Red Globe'at veraison,which were bagged by various polyethylene film bags(red,orange,green,blue and white) and silver paper(shading treatment). Quality characteristics of berry,such as the berry weight,sugar and acid accumulation,berry coloring and anthocyanin synthesis from veraison to maturation stage,were measured and analyzed.【Results】The results showed that the soluble solids,total sugar content and sugar-acid ratio of berry bagged with the blue filter film were increased. Compared with the white film control,glucose,fructose and sucrose content of berry bagged with blue film were increased by 7.2%,13.7%,and 17.2%,respectively. Additionally,the anthocyanin was enhanced significantly by blue light filter film and the hue angle(h) showed the minimum value at maturity. Significant differences in main composition of anthocyanin were observed in berries of different light filter film bagging treatment. At maturation,compared with the white film,cyanidin-3-O-glucoside and peonidin-3-O-glucoside content of berry with blue film were increased by 18.4% and 12.5% respectively. The activity of PAL was induced significantly under blue light filter film,which might increase anthocyanin accumula-tion. But the sugaracid ratio of berry by shading was the minimum value and anthocyanin synthesis was suppressed.【Conclusion】The research confirmed the importance of light environment around fruit for quality of V. vinifera L. in hot and humid regions of southern China. It also suggested that blue light filter film might improve the berry quality by regulating distribution of photosynthetic product and increasing anthocyanin accumulation resulted from the increase of PAL activity.