Eastern Cereal and Oilseed Research Centre, Research Branch, Agriculture and Agri-Food Canada, Ottawa K1A OC6, Canada.
Mycologia. 2002 Sep-Oct;94(5):850-5. doi: 10.1080/15572536.2003.11833178.
A strain of Acaulospora rehmii was, for the first time, successfully grown in vitro on Ri T-DNA transformed carrot roots allowing the in situ observation of Acaulospora spore development and of extraradical thin-walled hyphal swellings. The sporogenous hypha developed intercalarly along thin-walled coenocytic hyphae. The distal part of the sporogenous hypha swelled slightly as a sporiferous saccule primordium followed by the differentiation of a lateral spore primordium along the neck of the sporogenous hypha. Both structures matured simultaneously, and the sporiferous saccule began to collapse after spore maturation and complete differentiation of the spore wall. Several of the in situ observations on in vitro differentiated A. rehmii spores are concordant with previous ontogenic studies done on other Acaulospora species obtained from in vivo cultures. New and original observations on the early developmental stages of sporiferous saccules and spores and on the occurrence of small diameter intercalary hyphal swellings provide additional elements in the study of Acaulospora sporulation process and life cycle.
一株嗜钙无梗囊霉（Acaulospora rehmii）菌株首次在 Ri T-DNA 转化的胡萝卜根上成功进行了体外培养，从而可以原位观察无梗囊霉孢子的发育和根外薄壁菌丝膨大体。产孢菌丝沿着薄壁合胞体菌丝间生长。产孢菌丝的远端部分稍微膨胀，形成孢子囊原始体，随后在产孢菌丝的颈部沿侧向分化出一个孢子原始体。两个结构同时成熟，在孢子成熟和完全分化后，孢子囊开始塌陷。在体外分化的 A. rehmii 孢子上进行的一些原位观察结果与之前在体内培养获得的其他无梗囊霉菌种的个体发生研究结果一致。关于孢子囊和孢子早期发育阶段以及小直径间生菌丝膨大体的发生的新的和原始的观察结果为无梗囊霉孢子发生过程和生活史的研究提供了更多的依据。
