Błaszkowski Janusz, Kovács Gábor M, Balázs Tímea
Department of Plant Protection, University of Agriculture, Słowackiego 17, PL-71434 Szczecin, Poland.
Mycologia. 2009 Mar-Apr;101(2):247-55. doi: 10.3852/08-087.
A new arbuscular mycorrhizal fungal species of genus Glomus, G. perpusillum (Glomeromycota), forming small, hyaline spores is described and illustrated. Spores of G. perpusillum were formed in hypogeous aggregates and occasionally inside roots. They are globose to subglobose, (10-)24(-30) microm diam, rarely egg-shaped, oblong to irregular, 18-25 x 25-63 microm. The single spore wall of G. perpusillum consists of two permanent layers: a finely laminate, semiflexible to rigid outer layer and a flexible to semiflexible inner layer. The inner layer becomes plastic and frequently contracts in spores crushed in PVLG-based mountants and stains reddish white to grayish red in Melzer's reagent. Glomus perpusillum was associated with roots of Ammophila arenaria colonizing sand dunes of the Mediterranean Sea adjacent to Calambrone, Italy, and this is the only site of its occurrence known to date. In single-species cultures with Plantago lanceolata as host plant, G. perpusillum formed vesicular-arbuscular mycorrhiza. Phylogenetic analyses of partial SSU sequences of nrDNA placed the species in Glomus group A with no affinity to its subgroups. The sequences of G. perpusillum unambiguously separated from the sequences of described Glomus species and formed a distinct clade together with in planta arbuscular mycorrhizal fungal sequences found in alpine plants.
描述并图示了一种新的球囊霉属丛枝菌根真菌，微小球囊霉（球囊菌门），其形成小的、透明的孢子。微小球囊霉的孢子形成于地下聚集体中，偶尔也在根内形成。它们呈球形至近球形，直径（10 -）24（- 30）微米，很少呈卵形，长圆形至不规则形，18 - 25×25 - 63微米。微小球囊霉的单孢子壁由两层永久性层组成：一层精细分层、半柔韧至坚硬的外层和一层柔韧至半柔韧的内层。内层会变成可塑性的，在基于PVLG的封固剂中压碎的孢子中经常收缩，在梅尔泽试剂中染成红白至灰红色。微小球囊霉与定居在意大利卡拉布罗内附近地中海沙丘上的沙鞭根相关联，这是迄今为止已知的其唯一发生地点。在以披针叶车前为寄主植物的单物种培养中，微小球囊霉形成泡囊 - 丛枝菌根。对nrDNA的部分SSU序列进行系统发育分析，将该物种置于球囊霉A组，与其亚组无亲缘关系。微小球囊霉的序列与已描述的球囊霉物种的序列明确分开，并与在高山植物中发现的植物内丛枝菌根真菌序列一起形成一个独特的分支。
