| Summary: | 博士 === 國立中興大學 === 農藝學系所 === 100 === Vitis thunbergii, V. kelungensis, and V. flexuosa are three common wild grapes in Taiwan. Among other things, they have been used in the past as a medicinal crop to prevent flu and hepatitis. Despite their uses,
little work has been done on the identification of their botanical origins. In the study, the anatomical characteristics and variations among the three wild-grape species in Taiwan are analyzed. The annual variation of active components is investigated to identify the optimal harvesting period. In addition, ISSR DNA markers are applied to perform polymorphism analysis of collections in order to characterize the variation of genomes.
In order to examine the variation among species and provide information on conservation, breeding, product development and utilization, the three species were cultivated at the same location, and then characterized by vascular bundle, phloem fibers bundle and pith ray with paraffin sectioning. The results are summarized as below: the transverse section of the leaf’s midrib among the three wild-type species are identified their anatomical characters. The transverse section indicates that the adaxial vascular bundle is located at adaxial surface while the abaxial bundle is located on the other side. The number of abaxial vascular bundle ranges from 1 to 3 in V. thunbergii, 5 to 7 in V. kelungensis, and 4 to 5 in V. flexuosa. There is one groove on the adaxial surface in the transverse section of petioles. Several cortex vascular bundles disperse along the adaxial surface in the petiole groove while the others disperse separately in a ring which contains 2 adaxial vascular bundles and 5 primary abaxial vascular bundles. Four undeveloped or unidentified secondary abaxial vascular bundles disperse along primary abaxial vascular bundles. The number of secondary abaxial vascular bundles is 4 in V. thunbergii, 6 in V. kelungensis and 6 in V. flexuosa. The surface of the stem is smooth and almost round or oval. The Caliber of the stem is perpendicular to the pith.
The cortex contains discontinuous fiber bundles. Xylem and phloem are separated by ray and bunched up, respectively. The number of phloem fiber bundles ranges from 2 to 3 in V. thunbergii, 4 to 5 in V. kelungensis, and 2 to 4 in V. flexuosa. The number of pith rays range from 17 to 26 in V. thunbergii, 27 to 41 in V. kelungensis, and 19 to 26 in V. flexuosa.
Resveratrol, piceid, kaempferol, and four flavonoid glycosides are active components present in the three wild-type species, V. thunbergii、V. kelungensis, and V. flexuosa. In this study, samples collected in Taiwan were used as to investigate the variation in active components among collections, seasons, and ages. The correlation between active components and various plant parts was also analyzed. The results are summarized as follows. Resveratrol content is evaluated in four plant parts at various times of the year. The results indicate that V. flexuosa has the highest resveratrol content, followed by V. thunbergii, and V. kelungensis. The root, stem and young stem are found to contain the highest resveratrol content. The concentration of kaempferol and the four flavonoid glycosides is found to be the highest in the leaves. The amount of rutin, hyperin, and isoquercitrin in the leaf is the highest in V. thunbergii. The amount of quercitrin in the leaf is the highest in V. kelungensis. During the growth period of V. thunbergii and V. flexuosa, resveratrol peaks from December to March. V. kelungensis has the greatest resveratrol content from December to February during the growth period. The amount of resveratrol and piceid in the roots of V. thunbergii and V. kelungensis collections is higher in March than in August. The amount of resveratrol and piceid in the stem of V. thunbergii and V. flexuosa collections is higher in March than in August. The concentration of isoquercitrin, hyperin, and kaempferol in the young stem V. thunbergii collections is higher in March than in August. The concentration of piceid, rutin, hyperin, and kaempferol in the leaf of V. kelungensis and V. flexuosa collections was higher in August than in March. The concentration of piceid in the leaf of V. thunbergii collections is higher in March than in August. The concentration of hyperin and isoquercitrin in the leaves of V. thunbergii and V. flexuosa collections is higher in March than in August. The 3-year-old V. thunbergii and V. kelungensis have the highest levels of resveratrol and piceid. The 1-year-old individuals show the highest levels of kaempferol and flavonoid glycosides contents. The 3-year-old V. flexuosa has the highest levels of resveratrol and piceid in the stem, young stem and leaf. The 1-year-old individuals show the highest levels of kaempferol and flavonoid glycosides.
Genetic markers of inter-simple sequence repeat（ISSR）were used to analyze different species among three wild-grape collections collected from different locations of Taiwan. Understanding variation among species can provide information for identification and labeling. The analysis results are summarized as follows. A total of 9 primers with high repetition were screened from 100 ISSR primers in consecutive experiments. 168 DNA fragments were detected which were 100 percent polymorphic. The similarity coefficients range from 0.10 and 0.76. The UBC 808 primer generates 19 polymorphic bands, including a specific band at 1100 bp in V. thunbergii. The UBC 834 primer generates 19 polymorphic bands, including the most significant at 530 bp in V. kelungensis. The UBC 808 primer generates 19 polymorphic bands, the most specific band at 600 bp in V. thunbergii and V. flexuosa.
The result of cluster analysis shows that wild-grape species can be divided into 4 groups based on genetic similarity with 0.28 as the critical point. Cluster Ι has only one collections, VF-5, from V. flexuosa. Cluster Π has eight collections from V. kelungensis. Cluster Ⅲ has eight collections from V. flexuosa. Cluster Ⅳ has nine collections from V. thunbergii. After the principal component analysis, all of the collections can be classified into 4 groups. According to the result by using 2 markers including 1100 and 530, collections of V. thunbergii, V. kelungensis, and V. flexuosa can also be clustered in 4 groups.
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