De Souza Francisco Adriano, Declerck Stéphane, Smit Eric, Kowalchuk George A
Empresa Brasileira de Pesquisa Agropecuária, Embrapa Agrobiologia (CNPAB), Caixa Postal 74505, CEP 23851-970, Rodovia BR 465-RJ, km 7, Seropédica, Rio de Janeiro State, Brazil.
Mycol Res. 2005 Jun;109(Pt 6):697-706. doi: 10.1017/s0953756205002546.
The arbuscular mycorrhizal (AM) fungus Scutellospora reticulata (CNPAB11) was characterized using morphological, ontogenetic and molecular approaches. Spore ontogenesis was studied using Ri T-DNA transformed carrot roots and observations were compared with those published for eight other, pot-cultured, Scutellospora species. The sporogenesis of S. reticulata exhibited an unreported pattern of outer spore wall differentiation. In addition, Denaturing Gradient Gel Electrophoresis (DGGE), targeting the V9 region of the SSU nrDNA, was used to differentiate S. reticulata from 16 other Scutellospora species and results were confirmed by sequencing analysis. Phylogenetic analyses, using nearly full length SSU nrDNA sequences, grouped S. reticulata in a cluster together with S. cerradensis and S. heterogama, species that share similar spore wall organization and also possess ornamented external walls. PCR-DGGE and sequence analysis revealed intragenomic SSU nrDNA polymorphisms in four out of six Scutellospora species tested, and demonstrated that SSU nrDNA intragenomic polymorphism could be used as a marker to differentiate several closely related Scutellospora species.
利用形态学、个体发育学和分子生物学方法对丛枝菌根（AM）真菌网状盾巨孢囊霉（CNPAB11）进行了特征描述。使用Ri T-DNA转化的胡萝卜根研究了孢子个体发育，并将观察结果与已发表的关于其他8种盆栽盾巨孢囊霉属物种的结果进行了比较。网状盾巨孢囊霉的孢子发生表现出一种未报道过的外孢子壁分化模式。此外，针对小亚基核糖体DNA（SSU nrDNA）的V9区域的变性梯度凝胶电泳（DGGE）被用于区分网状盾巨孢囊霉与其他16种盾巨孢囊霉属物种，测序分析证实了结果。利用近乎全长的SSU nrDNA序列进行系统发育分析，将网状盾巨孢囊霉与塞拉多盾巨孢囊霉和异形盾巨孢囊霉归为一个聚类，这些物种具有相似的孢子壁结构且外壁有纹饰。PCR-DGGE和序列分析揭示了在所测试的6种盾巨孢囊霉属物种中有4种存在基因组内SSU nrDNA多态性，并证明SSU nrDNA基因组内多态性可作为区分几种近缘盾巨孢囊霉属物种的一个标记。
