Evaluation Of Fruit Texture Of Different Grape Varieties And Comparative Study On Two Different Trellis System Of ’Shine-Muscat’

Grape with soft and succulent flesh and thin and juicy skin,during transportation,which can easily be mechanical damage to be break or threshing,resulting in bacteria infection and quality reduction,affecting the commercial fruit finally,so in terms of its fresh quality,it is of great significance to cultivate and promote high-quality varieties with crisp texture and strong pulling force of fruit stalk.On the other hand,proper trellis system cultivation of grapes can optimizing the growth,leaf curtain environment,fruit quality and yield,promote high-quality,simplified and efficient production.In this study,we evaluated the texture traits of 26 grape varieties,and combined with pulling force and stalk morphological structure tests to select crisp texture and tensile strength varieties.By comparing the effects of two different trellis which the double-cross V-shaped and the H-horizontal shaped on the growth and development,the physiological characteristics,the canopy micro-climate,the fruit quality and the branches nutrition reserves of the‘Shine-Muscat’ grape,in order to provided the theoretical basis and scientific basis for selecting grape trellis suitable for the Guanzhong region of Shaanxi.(1)By investigating the growth performance of 26 grape varieties,the phenology period of different grape varieties was determined and the rule of growth results was understood.It was found that the budding stage mainly concentrated in late March to early April,and the earliest budding varieties was ‘Bixiang Wuhe’,‘Jinxiangyu’ and ‘Juxing’.In mid to late May,all varieties gradually enter the flowering period,which generally lasts for about 1 week.In late June,grape begin to soften and colored,and the difference in time gradually widens.(2)The texture of different grape varieties was measured by TPA method and the results showed the most hardness is ‘Summer Black’,the smallest is ‘Black Beet’.And the hardness of grape was significantly correlated with the springiness,gumminess and chewiness.The PCA extracted two main factors which chewiness,gumminess and cohesiveness have a great influence on texture to reflect some extent the main textural changes.(3)The pulling force of different grape varieties were measured by tension machine at the mature period that found the changes ranged from 2.67 N to 8.85 N,and which the largest and smallest are ‘Red Globe’ and ‘Black Beet’.The connection with the morphological structure of the fruit stalk indicates that the pulling force strength of the grape fruit stalk was significantly and positively correlated with its fruit hardness,grain weight,fruit stalk length,and the cross section area of the fruit stalk and pedicel.Grape varieties with stronger pulling force of fruit stalk have a more resistant and stable connection between the fruit stalk with the fruit brush than weaker varieties.(4)The fruiting branch rate of H-shaped is higher than V-shaped after the second nodes.The germination rate and flowering rate of new shoots in the first bud position reached more than 70 %,and the H-shaped was significantly higher than that of the V-shaped.The thickness and length of the new shoots in H-shaped are lower than in V-shaped,however,the growth trend is flatter than that of the V-shaped,which means trellis system can change the growth potential.(5)The SPAD values,the leaf area and leaf area index of the H-shaped trellis are higher than those of the V-shaped trellis,which can significantly improve photosynthetic characteristics and transforms the canopy micro-climate,increasing ventilation and illumination,finally laying the foundation for fruit yield and quality.(6)Compared with V-shaped,the yield of ‘Shine-Muscat’ grape cultivated under H-shaped increased significantly and could effectively improve the internal quality,fruit texture,stem morphology and pulling force.After defoliation,the starch content of the annual branches in H-shaped was significantly higher than the V-shaped in the fifth node,which indicating the H-shaped were more conducive to carbon accumulation in winter and nutrients storage for the next year.In general,the H-shaped horizontal trellis can be selected in Shaanxi grape production.