长根小奥德蘑双孢菌株与四孢菌株核相变化的比较

Comparison of the behavior of nuclei between bisporic and tetrasporic strains in Oudemansiella radicata

用双苯并咪唑(Hoechst33258)染色法分别对长根小奥德蘑Oudemansiella radicata双孢菌株和四孢菌株的菌丝、子实体、担孢子进行染色观察,结果表明:双孢长根小奥德蘑菌丝细胞多为单核,无锁状联合;原担子中单核进行一次有丝分裂形成两个横向或纵向排列的子核,这2个子核分别进入2个担孢子中,留下无核的空担子;成熟担孢子具有一个核。四孢长根小奥德蘑菌丝细胞大多数为双核,具有锁状联合;进入原担子中的两个单倍性细胞核先发生核配,形成一个二倍性的核,再经过减数分裂形成四个染色体减半的单倍性子核,4个子核分别进入4个担孢子中,留下无核的空担子;成熟担孢子也具有一个核。对长根小奥德蘑双孢子实体形成的机理进行了推测。

Fruiting bodies,mycelia and basidiospores of bisporic and tetrasporic strains in Oudemansiella radicata were stained by bisbenzimide（Hoechst 33258） and observed under fluorescence microscope.The results were as follows：Mycelia of the bisporic strain were monokaryotic and had no clamp connection.The monokaryotic probasidium underwent one round of mitosis and produced two nuclei in the basidium.These two nuclei were then separately transferred into two basidiospores,leaving an empty basidium.As a result,each of the two mature basidiospores had only one nucleus.However,most mycelia of the tetrasporic strain were dikaryotic and had clamped connections.During fruiting body development,the two haploid nuclei in the basidium fused and formed a diploid nucleus.Subsequently,the diploid nucleus underwent meiosis and produced four haploid nuclei.These four nuclei were separately transferred into four basidiospores.The mature basidiospore of the tetrasporic strain each had only one nucleus.The possible mechanisms for the formation of bisporic fruiting bodies of Oudemansiella radicata were suggested and discussed.