Laboratory of Plant Genetic & Breeding, Anhui Agricultural University School of Life Science, 130 Changjiang West Road, Hefei, 230036, People's Republic of China.
Mol Biol Rep. 2012 Jan;39(1):451-9. doi: 10.1007/s11033-011-0758-6. Epub 2011 May 6.
Fusarium wilt caused by the fungus Fusarium oxysporum f. sp. cubense race 4 (FOC4) results in vascular tissue damage and ultimately death of banana (Musa spp.) plants. Somaclonal variants of in vitro micropropagated banana can hamper success in propagation of genotypes resistant to FOC4. Early identification of FOC4 resistance in micropropagated banana plantlets is difficult, however. In this study, we identified sequence-characterized amplified region (SCAR) markers of banana associated with resistance to FOC4. Using pooled DNA from resistant or susceptible genotypes and 500 arbitrary 10-mer oligonucleotide primers, 24 random amplified polymorphic DNA (RAPD) products were identified. Two of these RAPD markers were successfully converted to SCAR markers, called ScaU1001 (GenBank accession number HQ613949) and ScaS0901 (GenBank accession number HQ613950). ScaS0901 and ScaU1001 could be amplified in FOC4-resistant banana genotypes ("Williams 8818-1" and Goldfinger), but not in five tested banana cultivars susceptible to FOC4. The two SCAR markers were then used to identify a somaclonal variant of the genotype "Williams 8818-1", which lost resistance to FOC4. Hence, the identified SCAR markers can be applied for a rapid quality control of FOC4-resistant banana plantlets immediately after the in vitro micropropagation stage. Furthermore, ScaU1001 and ScaS0901 will facilitate marker-assisted selection of new banana cultivars resistant to FOC4.
尖孢镰刀菌古巴专化型 4 号小种（FOC4）引起的枯萎病会导致维管束组织损伤，最终导致香蕉（Musa spp.）植株死亡。体外微繁殖的香蕉体细胞无性系变异会阻碍对 FOC4 具有抗性的基因型的繁殖成功。然而，早期鉴定微繁殖的香蕉苗对 FOC4 的抗性较为困难。在本研究中，我们鉴定了与 FOC4 抗性相关的香蕉序列特征扩增区域（SCAR）标记。使用来自抗性或敏感基因型的混合 DNA 和 500 个任意 10 碱基寡核苷酸引物，鉴定了 24 个随机扩增多态性 DNA（RAPD）产物。这 24 个 RAPD 标记中的两个成功转化为 SCAR 标记，分别命名为 ScaU1001（GenBank 登录号 HQ613949）和 ScaS0901（GenBank 登录号 HQ613950）。ScaS0901 和 ScaU1001 可以在 FOC4 抗性香蕉基因型（“Williams 8818-1”和 Goldfinger）中扩增，但不能在 5 个测试的易感 FOC4 的香蕉品种中扩增。然后，使用这两个 SCAR 标记来鉴定基因型“Williams 8818-1”的体细胞无性系变异体，该变异体失去了对 FOC4 的抗性。因此，鉴定的 SCAR 标记可用于在体外微繁殖阶段后立即对 FOC4 抗性的香蕉苗进行快速质量控制。此外，ScaU1001 和 ScaS0901 将有助于标记辅助选择对 FOC4 具有抗性的新香蕉品种。
