Effect of application of reflecting film and leaf removal on microclimate around fruiting zone and fruit quality of Vitis quinquangularis Rehd. grape

ABSTRACT

Objective: To provide theoretical basis for further optimizing the cultivation measures and improving the wine quality of Vitis quinquangularis Rehd. grape in Guangxi, the effects of application of reflecting film and leaf removal at the beginning veraison on the microclimate in the fruiting zone and fruit quality of V. quinquangularis Rehd. Grape cv. Yeniang No.2 were analyzed. Method: In Nanning, Guangxi, Yeniang No.2 was material, and leaf removal and reflective transfer film laying treatments were conducted when fruits started to change color, and without leaf removal and reflective transfer film laying treatments were as control. The variations in temperature, humidity and light conditions before and after the treatments were traced using HOBO weather stations. The berry quality indexes of fruit samples under the two kinds of light control treatments and the control at each developmental stage were determined. Result: Both treatments achieved the purpose of enhancing the light intensity around fruiting zone of Yeniang No.2, and the effect of leaf removal treatment was more obvious. The daily average photosynthetic effective radiation was increased by 6 to 13 times compared with the control, and the daily average of total solar radiation increased by 2 to 4 times when compared with the control. The two treatments also reduced the temperature difference between day and night for Yeniang No.2, the daily maximum temperature, the humidity difference between day and night and the daily maximum humidity and increased the daily minimum temperature and humidity. Leaf removal and reflective film treatments reduced the fresh weight and titratable acid content of grape at harvest, but increased the soluble solids, improved skin color and red hue.