SRAP和SSR标记构建的甘蓝型油菜品种指纹图谱比较

Comparision of cultivar fingerprints constructed with SRAP and SSR markers in Brassica napus L.

利用SRAP(sequence-related amp lified polymorph ism)和SSR标记构建了甘蓝型油菜品种指纹图谱,并对两种标记方法进行了比较。结果表明:(1)每对SRAP引物扩增出20.36个条带,其中4.44个是清晰、易于辩认的多态性带;每对SSR引物扩增出3.88个条带,均为多态性条带。(2)采用25对SRAP和SSR引物分别构建40个和75个品种的特异指纹图谱,SRAP指纹中具有特异图谱的比例(82.5%和50.7%)高于SSR指纹图谱的结果(60.0%和44.4%)。品种数越多具有特异指纹的品种越少。(3)运用引物组合法构建品种指纹图谱,大大地提高了指纹图谱的特异性。25对SSR引物组合扩增97个多态性谱带,两个不同的品种具有相同谱带的概率只有6.3108×10-30。组合指纹图谱比组合数码图谱更直观。与SRAP标记相比,SSR标记以其扩增谱带少、易于识别和统计而更适合用于引物组合法构建品种指纹图谱。

Fingerprints of cultivars were constructed with SRAP（sequence -related amplified polymorphism） and SSR markers in Brassica napus L. Comparision between these two marker systems was carried out. Three conlusions can be drawn from this study. （1） Every primer combination of SRAP generated 20.36 bands in average, in which there were 4.44 polymorphic bands. Every primer pair of SSR generated 3.88 bands in average, which were all polymorphic. （2） Fingerprints of forty cultivars and seventy -five cultivars were constructed with 25 SRAP primer pairs and SSR primer pairs, repectively. The ratios of distinct fingerprints （82.5% and 50.7% ） revealed by SRAP markers in 40 and 75 cultivars were： higher than those （60.0% and 44.4% ） revealed by SSR markers. The cultivars with distinct fingerprints in different populations varied. The larger the population, the less number of cultivars with distinct fingerprints, （3） The fingerprints constructed with primer combinations were much more distinct than those consturcted with individual primers, The primer combination of 25 SSR primers could generate 97 polymorphic bands. In the fingerprints constructed with SSR primer combination, the probability that two different cultivars shared the same fingerprints was only 6. 3108 × 10^-30. Combined fingerprints were more visible than combined digital fingerprints. Compared with SRAP markers, SSR markers detected less bands and the bands were easier to be identified and analyzed. Therefore, SSR markers are more suitable for constructing cultivar combined fingerprints than SRAP markers.