Fruit Quality Of Ziziphus Jujuba ‘Dongzao' Under Facility Conditions

Ziziphus jujuba ‘Dongzao' is a fresh jujube which with the most cultivated area and the best commercial quality in China.It is important to define the cultivation mode of jujube fruit,improve the fruit quality and prolong the shelf life for the development of fresh jujube industry.Therefore,‘Dongzao'(5~7 years old)was used as the material,and field investigation and indoor test were used for the research,the changes of the appearance and nutrient qualities of jujube fruits under different cultivation patterns(Solar glasshouse,Quilt shed,Two-layer plastic shed,Plastic shed and Open-field cultivation),different harvesting periods(white mature(WM),beginning red(BR),half-red(HR))and different preservation methods(bagging opening,bagging sealing and not bagging)were investigated.The following findings were obtained.1.The effect of cultivation patterns on the fruit quality of jujube.Compared with the ‘Dongzao' cultivated in open field,the jujube fruits cultivated in facility has uniform size and good consistency.The water content of fruit is high,the peel hardness is small,the brittleness ratio is high,the taste better in general.At the same time,the soluble solids,total sugar content and sugar-acid ratio of the fruit are significantly higher than those of the open-field cultivation,which also promote the accumulation of total phenol content.Principal component analysis was used to analyze the fruit comprehensive quality of ‘Dongzao' under five cultivation patterns,which in solar glasshouse is the best.2.The effect of harvest time on fruit quality of jujube.‘Dongzao' was harvested at WM,BR,HR periods,variation trend in the appearance and nutrient qualities of fruit under four protected cultures are similar.On the day of harvest,the quality of fruit in WM was poor.With the extension of storage time,the quality of jujube fruit decreased slowly,and the appearance quality was good.The appearance quality and nutritional quality of jujube fruit in BR are close to that in the half red stage,but the storage quality is slightly worse than that in WM.Jujube fruits harvested in HR have bright color,uniform size,high soluble solid,total sugar and other nutrients,and the best edible quality.However,the color of jujube fruit in HR darkened during storage,the fruit shriveled seriously,the nutritional quality decreased rapidly,and the jujube fruit was not resistant to storage.3.The effect of fresh-keeping method on fruit quality of jujube.Under normal temperature storage condition,the fruit quality of jujube in the bag is obviously better than that not in the bag.Bagged jujube are resistant to storage,at the same time,the contents of total sugar,sugar-acid ratio,total phenol and total flavonoids in bagged fruits decreased slowly,and the contents of vitamin C and total soluble solid in jujube fruits increased significantly.Due to the strong air permeability,the bagging opening of ‘Dongzao' is weak in water loss,the fruit is crisp,and the nutritional quality is high,which is conducive to the storage of jujube fruit at room temperature.Overall,this paper screened out the suitable cultivation management mode,harvest maturity and fresh preservation mode in the production process of fresh jujube production areas,and provided a better guidance for the establishment cultivation of fresh jujube standardized industry development.