絲瓜屬作物遺傳歧異性之分析

Genetic diversity among the lines and cultivars of Luffa species

謝麗玲(Li-Lin Hsieh)

指導教授 ： 楊雯如

共同指導教授 ： 林宗賢(Tzong-Shyan Lin)

國立臺灣大學/生物資源暨農學院/園藝學研究所/碩士(2005年)

https://doi.org/10.6342/NTU.2005.10415

摘要

本試驗主要在探討絲瓜屬作物之遺傳歧異性，絲瓜屬作物包括圓筒絲與稜角絲瓜，二者在形態上如花器構造、開花時間以及果實形狀等都有很大的差異。本試驗以RAPD技術分析絲瓜屬作物遺傳歧異性，20個引子產生148個穩定的條帶，其中123個條帶表現多型性；根據RAPD分析，圓筒絲瓜與稜角絲瓜相似性介於0.02~0.11，顯示二者具有高度的遺傳歧異性；圓筒絲瓜與稜角絲瓜一代雜交種208與圓筒絲瓜群之相似性介於0.36~0.45，而其與父本稜角絲瓜A28之相似性則為0.45，顯示其遺傳組成介於二親本之間；編號247的品系為種間一代雜交種與稜角絲瓜回交後代 (BC1F1)，其與母本208 (F1) 及父本稜角絲瓜A28之相似性分別為0.79及0.57，而其與圓筒絲瓜品系 (種) 的相似性則介於0.31~0.39，顯示247 (BC1F1) 的遺傳組成較似稜角絲瓜，而具較少的圓筒絲瓜基因，符合其遺傳背景；雙依品種與圓筒絲瓜群相似性介於0.60~0.73，於分佈圖中，雙依品種位於208 (F1) 與圓筒絲瓜群之間，推測其可能有導入稜角絲瓜之基因；參試的圓筒絲瓜品系 (種) 相似性高，其中更有若干品系 (種) 相似性為1，顯示參試的圓筒絲瓜遺傳歧異性低，遺傳背景並不大，然仍可分為主要二群，而中國大陸商業品種皆被分於同一群，顯示相同來自中國大陸的商業品種遺傳組成仍較相近。由以上結果顯示RAPD技術可應用於絲瓜屬作物遺傳歧異性與親緣關係之分析並可鑑別種間雜交種。
於圓筒絲瓜遺傳歧異性方面，以外表性狀配合RAPD分子性狀進行分析，分析所用之19個外表性狀如下：包括6個種子性狀：種子長度、種子寬度、種子長寬比、種子厚度、種子百粒重、種皮顏色，3個葉片性狀：葉片長度、葉缺裂長度、葉長與葉缺裂長之比值，1個花色性狀，及9個果實性狀：果皮顏色、果皮粗糙度、果實重量、果實長度、果實徑寬、果實長度與徑寬之比值、果梗長度、花痕長度、花痕徑寬。然而因果實蠅危害嚴重，很多品系 (種) 之果實受傷嚴重，無法取得果實性狀數據，因此，再以去除果實性狀後的12個植株形態性狀進行分析； RAPD分子性狀分析與19個外表性狀分析所得之群聚關係較為相似；群集分析與主成份分析結果顯示對群聚關係影響力較大的性狀皆為果實性狀，如果實長度與徑寬之比值、果實徑寬、果梗長度、果皮顏色，植株形態性狀影響則較小，顯示果實性狀於圓筒絲瓜遺傳歧異性的分析上扮演重要的角色。

關鍵字

種間雜交 ； RAPD ； 外表性狀 ； 圓筒絲瓜 ； 稜角絲瓜

並列摘要

The objective of this study was to identify the genetic diversity among the lines and cultivars of Luffa spp., including L. cylindrica and L. acutangula. L. cylindrica and L. acutangula have well-differented morphological characters, differing in floral structure, time of anthesis and the fruit structure etc. In this study, genetic diversity was assessed among the lines and cultivars of Luffa spp., using 20 randomly amplified polymorphic DNA (RAPD) primers. These primers produced 148 stable bands, among which, 123 bands were polymorphic. Based on the RAPD data, the L. cylindrica cluster differentiated from the L. acutangula cluster at the level of 0.02 to 0.11 genetic similarity, indicating high level of genetic diversity between L. cylindrica and L. acutangula. The interspecific hybrid, the line 208, was produced by crossing L. cylindrica with L. acutangula. The interspecific hybrid differentiated from the L. cylindrica cluster and from the L. acutangula line A28 at the level of 0.36 to 0.45 and 0.45 genetic similarity, respectively, indicating that interspecific hybrid was genetically intermediate between both parental plants. The line 247 was produced by backcrossing of interspecific hybrids to L. acutangula line A28. The line 247 differentiated from individual parents at the level of 0.79 and 0.57 genetic similarity, respectively; moreover, the line 247 differentiated from L. cylindrica cluster, except the cultivar Shuang-Yi, at the level of 0.31 to 0.39 genetic similarity, indicating that the line 247 had closer relationship with L. acutangula than with L. cylindrica. This result was consistent with the genetic background of the line 247. The cultivar Shuang-Yi differentiated from the L. cylindrica cluster at the level of 0.60 to 0.73 genetic similarity. According to the ordination of all the 80 lines and cultivars determined by the first two principal component axes on the basis of 123 polymorphic bands, the cultivar Shuang-Yi was located between the L. cylindrica cluster and the line 208. It could be hypothesized that there had been some genetic introgression of L. acutangula germplasm into the cultivar Shuang-Yi. There was high level of genetic similarity among all the L. cylindrica lines and cultivars tested; some of the L. cylindrica lines and cultivars were identical genetically, indicating low level of genetic diversity and narrow genetic base among the L. cylindrica. However, all the L. cylindrica lines and cultivars tested could be divided into two clusters, and all the cultivars from China were in the same cluster, indicating they had closer relationship with each others. This study indicated that RAPD marker can be useful in assessing the genetic diversity and relatedness of the domesticated varieties of Luffa.
In addition to RAPD analysis, the analysis of 19 phenotypic characters was carried out to assess the genetic diversity of L. cylindrica. The phenotypic characters investigated included seed length, seed width, seed length/seed width, seed thickness, weight per one hundred seed, seedcoat color, leaf length, leaf invagination, leaf length/leaf invagination, flower color, fruit skin color, fruit skin texture, fruit weight, fruit length, fruit width, fruit length/fruit width, pedicel length, remnant of stigma length, and remnant of stigma width. However, because of the serious damage caused by melon fly, the fruit characters of many lines and cultivars were lost. For this reason, the analysis of 12 phenotypic characters, not including the fruit characters, was also carried out to assess the genetic diversity. The result of the analysis of 19 phenotypic characters resembled the result of RAPD analysis more than that of 12 phenotypic characters did. According to cluster analysis and principal component analysis, fruit length/fruit width, fruit width, fruit length, pedicel length, and fruit skin color were the major discriminating characters, indicating that fruit characters had more influence on clustering than other characters did. Data based on the analysis of phenotypic characters showed that fruit characters played important roles in assessing the genetic diversity among L. cylindrica.

並列關鍵字

L. cylindrica ； L. acutangula ； interspecific hybrid ； RAPD ； phenotypic characters

參考文獻

潘詩怡. 2004. 蕹菜遺傳歧異性及白

翁儷倩. 2001. 柑橘遺傳歧異性之分析. 國立台灣大學園藝所碩士論文. 90pp.

參考文獻

中國農業科學院菜蔬研究所. 1987. 中國菜蔬栽培學. 農業出版社. p.602-607. 中國.

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