| Dongzao jujube (Zizyphus jujuba Mill. cv. Dongzao) is a kind of famous fresh-eating date in China. With the rapid development of Dongzao jujube's industry in recent years, some problems happened, such as the unanimity of fruit quality, confusion of varieties, and misconception of normal late-ripen dates as Dongzao jujube. In this paper, the heredity and diversity of Dongzao jujube were studied with morphology, palynology, photosynthesis, RAPD marker, fruit quality and storage physiology. The results showed that Chengwu Dongzao, one kind of normal late-ripen Chinese date, did not belong to the Dongzao jujube family. The definition of Dongzao jujube should be strictly complied with the conception in Chinese Fruit Tree Annals ?Date Volume. And the results also identified that there were significant differences in the height of trees, length and diameter of the first level branches, chlorophyll content in leaves, as well as the fruit taste, fruit shapes and the thickness of peels of the Dongzao jujube from five different original places, and the high rate of repeatability of experimental data also proved its genetic variation, which means that more good varieties will be gotten by further selection and improvement of Dongzao jujube.It has been found by studying that Huanghua and Gucheng in Hebei province, Zhanhua of Shandong province may be its provenance with the more oldest Dongzao jujube trees distribution over one hundred years even although no written data in record.It was identified by research that more variation happened in leaves, same as in branch, flower, fruit and core of fruit. The less variance in phenology of Dongzao jujube in different original places, and the difference of growth characters became smaller with the age increasing of trees. The flower of Dongzao jujube was the type of night-rend-bud, the pollens all shaped with equilateral triangle, netted veins, and cave-mesh with very low viability. Its daily and annual variation of photosynthesis rate and transpiration rate were showed with un-conspicuous two-peak curves. Obvious differences exist in the ratio of chlorophyll a/b ranged in the scope of 2.59-3.07. The index of florescence dynamics of Dongzao jujube from different original places varied with the location of leaves and nutrition conditions. The Fv/Fm value in sequence was NO.3>1>5>4>2.144 loci were gotten by RAPD marker analysis, in which 95 were polymorphic loci, and about 65.09% of the total. Genetic distance of Dongzao jujube of different sites was within 0-0.3631 and genetic identity were above 0.76.The estimation of leaves area has been much simplified by the establishment of general leaf area curve equation: S=0.366+0.66axb. The simulate equation of respiration intensity and post harvest days was set up as follows: Y=45.1729-4.7127x +0.1368x2 (R2=0.871) .Dongzao jujube was believed a kind of non-high respiration fruit by the analyzing of its ethylene content and respiration intensity. Storage life was given in sequence, No.4>2>1>3>5 after two months storage. Reasons of reduction of fruit quality were not same from different original places. No.5 shown mainly soften, but No2 were mostly rotten. The close parameters to correlate with fruit softening and browning were the content of Vitamin c, deoxidize sugar, total sugar and Water-soluble pectin and the activities of PE, PQ CAT.
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