Effect Of Different Canopy Managements On The Quality Of Winegrapes

In this study, winegrapes Cabernet Sauvignon and Ugni Blanc planted in Jingyang County of Shaanxi Province, and treated with pinching, removing old leaves and cluster thinning at veraison were to investigate the effect of canopy management on the maturity of winegrapes, fruit basic qualities, phenolics and volatile components by HPLC and GC-MS in order to provided the optimized canopy management and theoretical basis for Jingyang grape production area.The results of the study are as followed:(1). There were some differences between two vintages for Cabernet Sauvignon. for vintage 2013, the best fruit basic qualities management was medium crop load(12000 kg/hm2), 10 leaves pinching in new shoot length and removed 2 old leaves at veraison; for vintage 2014, the management “low crop load(8000 kg/hm2), 10 leaves pinching in new shoot length, removing 4 old leaves at veraison” showed the optimal berry quality.The results showed that the treatment “low crop load(8000 kg/hm2), 10 leaves pinching in new shoot length and removed 4 old leaves at veraison” had best berry quality for Ugni Blanc.(2). The high content of reducing sugar content for the canopy management of Cabernet Sauvignon was medium crop load, 10 leaves pinching in new shoot length and removing 2 leaves at veraison. In 2014, the reducing sugar content of mature Ugni Blanc berries showed that low crop load(8000 kg/hm2), shoot pinching at 10 eaves and 2 leaves removal at veraison come out top.(3). Shoot pinching kept at 10 leaves, shoot tip only retain secondary shoot to keep 3 leaves pinching constantly, on the medium crop load(12000 kg/hm2) and 4 old leaves removed at veraison was the best management in accumulating anthocyanin of Cabernet Sauvignon in Jingyang; non-anthicyanin phenolics reached the maximum content when crop load kept the 12000 kg/hm2 of crop load level, removing 2 leves, shoot pinching at 10 leaves, shoot tip only retain secondary shoot to keep 3 leaves pinching constantly. On the medium crop load(12500 kg/hm2), 6 leaves removed, shoot pinching kept at 10 leaves, shoot tip only retain secondary shoot to keep 3 leaves pinching constantly in this management, Ugni Blanc reached the maximum content of non-anthicyanin phenolics.(4). For Cabernet Sauvignon, 56 volatile substances were identified, including 17 esters, 7 Aldehydes, 18 alcohols, 1 ketone and 13 acids. The highest volatile content management presented in the treatment that high crop load(16000 kg/hm2), shoot pinching at 10 leaves and 4 old leaves removing at veraison, shoot tip only retain secondary shoot to keep 3 leaves pinching constantly.For Ugni Blanc, a total of 50 volatile compounds were identified, including 6 aldehydes, 10 esters, 15 alcohols, 12 acids, 4 terpenes, 1 ketone and 2 other types. The management “high crop load(18000 kg/hm2), shoot pinching kept at 10 leaves and 6 old leaves removing at veraison, shoot tip only retain secondary shoot to keep 3 leaves pinching constantly” reached the highest volatile content.According to the comprehensive data of 2013 and 2014, the best canopy management was medium crop load(12000 kg/hm2), 10 leaves pinching in new shoot length and removed 2 old leaves at veraison for Cabernet Sauvignon.For Ugni Blanc the canopy management “low crop load(8000 kg/hm2), 10 leaves pinching in new shoot length, removing 4 old leaves at veraison”was the best.