Study On Life Cycle Of Oudemansiella Radicata

Oudemansiella radicata which is an edible and medicinal basidiomycete. Currently, the biological characteristic and medicinal value of this fungus have been studied; however, the studies about its life cycle have not yet been reported. This is the first time to study the life cycle of Oudemansiella radicata comprehensively, the main contents and conclusions are as follows:1. Artificial cultivation in different developmental stages of Oudemansiella radicataModified the cultivation conditions of Oudemansiella radicata, and then observed the different stages of development and collected the spores to make the germination experiments. The results showed that the hyphae were white in the initial stage, and later generated taupe membrane. When the mycelia were matured, they were kinked, and then gradually formed primordium. The primordium was finally formed the button which developed into fruit body. Basidiospores produced on the fruit bodies. The spore germinated and developed into mycelium.2. Morpho-anatomy features in different developmental stages of Oudemansiella radicataThe temporary slide in different developmental stages of Oudemansiella radicata staining with Congo red showed that:a. there are two types of fruiting bodies in Oudemansiella radicata, which are bisporic strain and tetrasporic strain. There is no difference in those two types of fruiting bodies in Oudemansiella radicata. b. Mycelia of the bisporic strain had no clamp connection. However, mycelia of the tetrasporic strain had clamp connection. c. Basidium of the bisporic strain had two sterigmas, but tetrasporic strain had four sterigmas, a sterigma had a basidiospore. d. The basidiospore of Oudemansiella radicata was oval,13-18umx10-15um. e. The hyphae with many septa.SEM Photomicrograph of the mature Fruiting bodies a showed that the surface of basidium densely covered basidiospore. The surface of basidiospore was oval and smooth. Each basidium cell has produced four basidiospores in the tetrasporic strain.Fruiting bodies, mycelia and basidiospores of bisporic and tetrasporic strains in Oudemansiella radicata were stained by bisbenzimide (Hoechst33258) 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 stain each had only one nucleus.3. Study on life cycle of Oudemansiella radicata in using SNPs molecular markersAfter obtaining the sequences from the genomic library,12primer pairs were designed. The SNPs assay provided the different sequence information in different samples. A total of320SNPs were found in Oudemansiella radicata. The sequences and chromatographs indicated that the tetrasporic strain was a heterokaryon, while the bisporic strain was a homokaryons.Based on our observations and data, we proposed the following life cycle of Oudemansiella radicata. A spore germinated and developed into primary mycelium. Different polarities of mycelium anastomose, forming the secondary mycelium. When the secondary mycelium growed and mature, forming the tetrasporic fruiting bodies. When the mycelium did not anastomose, and then formed the bisporic strain. The bisporic fruiting bodies had two sterigmas.