Grapes "Nutrition Bead" Qualitative Research

Grape (Vitis L.) is a perennial deciduous woody liana. It’s not only as one of the oldest original plants, but also as one of fruit trees with the longest cultivation history and the highest production yield in the world. In this study, the "nutrition beads" secreted from Red Globe/Kyoho grapes were adopted as raw material, which were collected and counted in 2014-2015. Then the "nutrition beads" samples were sysmatically characterized by a series of technical measurmens, such as Zoom-stereo microscope (SZM), freezing field-emission scanning electron microscopy (Cryo-FESEM), Gas Chromatography-Mass Spectrometer (GC-MS) and Inductively coupled plasma mass spectrometry (ICP-MS), the information of occurrence regularity, morphological characteristics, volatile organic components, and mineral element constitutents were successfully investigated qualitatively and quantificationally. Overall, the related-prarameters about "nutrition bead" obtained in this study established a good theoretical and practical foundation for grape basic research, it is also with positive meaning for qualitative and quantitative research on morphological and physiological characteristics about "nutrition bead". The main results of this study are summarized as follows:1. The secretion regularity study of "nutrition bead" in grape plants:with the ripening of grape twigs, the general trend of the number of "nutrition bead" first increased and then decreased.The following part gave the detailed description:the number of "nutrition bead" increased gradually until it reached its peak at the end of May. And then in early June, the number of "nutrition bead" presented the sharpest reduction. As time went by to Mid-to-end of June, the amount of change reached to a relatively stable value. At last, its number showed the most significantly reduction in early July. By comparing of the two years’ experimental results, "nutrition bead" displayed a basically identical secretion regularity trendency. The location of "nutrition bead" expressed a big diversity. Meanwhile, the distribution density was also inhomogeneous, most of them focused on petiole and back of tender leaves; it also showed a cluster distribution phenomenon in the internode and petiole base. It is thus clear that certain correlation between "nutrition pearl" secretion quantity and the growth of grape plants was verified.2. The "nutrition bead" secreted from grape plant is with a high water content, reaching to 90.12%, in other words, the dry matter content is 10%.3. The "nutrition beads" observed results by Zoom-stereo microscope and freezing field-emission scanning electron microscopy:(1) From the Zoom-stereo microscope, we can observe "nutrition bead" generally displays round sphere and ellipsoid shape with a relatively big size difference. In general situation, their diameters are within 0.5～.5 mm. Besides, some tiny "nutrition beads" can also be found. Meanwhile, a pale green "delivery channel" is also observed at the connected region between grape plants and its base part. The color of "nutrition pearl" under the completely water loss state (also called, dry matter) is black. (2) We can clearly observe that "nutrition bead" presents a round ball shape with elliptic holes on the spherical surface by the freezing field-emission scanning electron microscopy. Simultaneously, there are many oval holes distribute on the surface of the grape plants, which are air holes of grape stems and leaves. And the blade back is crinosity with numerous frequent open and-shut oval pores. That is to say, grapes can absorb nutrients through the leaves, stems and immature berry.4. The volatile composition analytical results from "nutrition bead":66 species of volatile organic components are identified by GC-MS, including alcohol, olefin, phenol, acids, aldehyde, ketone, ester, alkane, nitrile and other compounds. To sum up, Red Globe Grape and Kyoho Grape are with four same ingredients, they are alpha-terpineol, trans/cis-2,6-azelaic enol, linalyl alcohol and hexyl alcohol. Therefore, that is why the "nutrition beads" secreted from these two kinds of grape species are with the smiliar aroma components while keep their respectively unique compositions. And the volatile components in "nutrition bead" derive from their own secreted structure which can produce aromatic substances.5. The elements qualitative research of "nutrition bead":21 kinds of mineral elements are detected using ICP-MS method, including B, Mg, P, K, Ca, Mn, Fe, Cu, and Zn etc. There are 9 kinds of essential elements in grape, which comes from the soil. Besides, the absorption ability of grape plants to various nutrients is different. And the relationship between the various nutrient elements is also very complex. All in all, various elements play an integrated physiological function to grape and "nutrition bead".