蘑菇质量和出菇能力的下降,恰是由于菌丝体在长期的营养增殖中发生退化和突变或是在连续大床栽培中发生遗传重组所致。这就是许多国家的制种工作仅局限于少数制种人员的缘故。菌丝体定期移植是传统的保种方法,运用这种方法必须确定三个条件:(1)移植周期;(2)合适的保藏培养基;(3)理想的保藏温度。以理论上讲,传代不能太频繁,以减少污染、技术差错和突变的危险。6～12个月 The decline of mushroom quality and fruiting ability is due to the degradation and mutation of mycelium in the long-term nutrition proliferation or the genetic recombination occurred in continuous bed cultivation. This is why the seed production in many countries is confined to only a few seed producers. Regular mycelial transplantation is a traditional method of seed protection, the use of this method must identify three conditions: (1) the transplant cycle; (2) the appropriate preservation medium; (3) the ideal storage temperature. In theory, passage should not be too frequent to reduce the risk of contamination, technical errors, and mutation. 6 to 12 months