以RAPD、ISSR分子標誌探討台灣大蒜品種（系）間之遺傳相關性

Abstract

本研究利用RAPD及ISSR兩種分子標誌，探討由台南區農業改良場義竹工作站所提供之大蒜種原50種（分別來自台灣、大陸、埃及、印度、印尼及菲律賓）；在農試所採集之15個台灣地方品種及二個韓國品種的嫩葉樣品；台大農藝系所收集之11個大陸品種等，一共80個大蒜品種（系）間的遺傳相關性。以RAPD的17條引子擴增出清晰容易判讀且具穩定再現性標誌共59個，其中23個為對照材料特有，僅36個條帶在大蒜品種（系）間具多型性（polymorphic），平均每引子可擴增出2.1組多型性標誌；以九條ISSR引子擴增共擴增出37個標誌，其中25個在大蒜品種（系）間具多型性之標誌， 12組為對照特有，平均每引子可擴增出4.11個多型性標誌。 以59個RAPD多型性標誌計算80個大蒜供試品種（系）的遺傳相似度（genetic similiary），介於0.16∼1.00，由群叢分析結果將參試品種（系）在平均遺傳相似度0.26分為三大群，且三群間的遺傳相似性低，大部分台灣品種（系）同群且無法區分，與印尼品種（系）也有很高的相似性，甚至無法區分； ‘新品種黑葉’、‘鳳山選二號’及花蒜種類與宜蘭地區品種（系）皆與‘北蒜’、中國大陸南方蒐集品種（系）在另一群中；而中國大陸北方山東、河南地區品種（系）則與菲律賓、印度等地品種（系）同在第三大群中。群叢分析結果大致與材料來源與類型或採收目的有相關性。主成分分析獲得之前三個主成分可解釋84%的變異量，品種（系）在前兩個主成分解釋79.6%變異的分佈與群叢分析結果類似。 以37組ISSR多型性標誌計算供試46大蒜品種（系）間遺傳相似度，由群叢分析結果將大蒜品種（系）在平均相似度0.12時一樣分為三大群，一、二兩群以台灣品種（系）為主，並包含印度、印尼、菲律賓等地品種（系），第一群中以大片黑系統品種（系）為主，第二群中則包含和美（硬骨小葉）、花蒜類及部分宜蘭品種（系），種類較多；第三群在相似度0.39可再分為兩小群，第一小群包含‘鳳山選二號’、‘花蒜選’與宜蘭地區品種（系）還有‘北蒜’與中國大陸南方蒐集品種（系），第二小群則為中國大陸北方山東、河南地區品種（系）。 利用RAPD、ISSR兩種分子標誌皆能區分台灣品種（系）與供試的中國大陸品種（系）。部分台灣品種（系）在兩種標誌分析結果相同，並且顯示台灣大蒜品種（系）間的遺傳組成相似性很高，採收青蒜用品種（系）間遺傳差異大於蒜頭用品種（系）之間。而由種原田間種植的性狀觀察，以硬骨性較多，成熟以早生與中生種較多。

The present study utilizes RAPD and ISSR molecular markers to analyze the genetic variations among 80 garlic accessions, including 50 collected by Yi-chiu, Tainan DAIS, 17 from TARI and 11 from china. In the RAPD analysis, 17 primers amplified 59 clearly scored markers. Among these, 23 markers were specific only in outgroup and 36 markers showed polymorphism among garlic accessions, with an average of 2.1 markers per marker. In the ISSR analysis, 37 markers were generated by 9 primers. Among them, 25 were polymorphic among garlic accessions and another 12 were outgroup specific. On average, each primer generated 2.78 markers. The genetic similarities among 80 garlic accessions, calculated by the data from 59 RAPD markers, ranged from 0.16 to 1.0. All garlic accessions can be grouped into three by the cluster analysis. The first group contain most Taiwan landraces and some Indonesian accessions and show complete similarities among them. Some Taiwan varieties, ie. ‘New Black Leaf’, ‘Feng Shan Sel. No2’and bolting type are grouped with Easter Taiwan Type in the second group. Also included in the same group are accessions from southern China. Garlics collected from Northern china are clustered in the third group together with accessions from the Philippines and India. The grouping corresponds to the accessions sources and harvest uses. In the principle component analysis, the first two component could explain 79.6% of variability and the two dimension distribution depicts the same results from cluster analysis. In the ISSR analysis, 37 polymorphic markers were generated from 46 garlic accessions and leek and green onion on check. The results from cluster analysis also group all garlics into three most Taiwan garlics in the first two group. The Large black Leaf type forms the first group while He-Mei, the Small black Leaf type, bolting type and some Easter type constitute the second, and the largest group. The third group could lie further divided into two groups, one comprising southern China accessions and one comprising northern China accessions. Both ISSR and RAPD markers could separate Taiwan garlics from China garlics. Some results are shared by both markers and indicated that high genetic similarities exis some landraces of the same uses. And genetic variation of garlic for leaf use is greater than that for bulb use. The field investigations of garlic plants indicate that the germplasms of Taiwan comprise more of hard leaf type than soft leaf type and more of early and medium maturity type than late type.