Great diversity in genomic dna of gastrodia elata bl . and armillaria mellea . was also demonstrated by completely different bands of the rapd between various growing periods of t8 and m . the complete different bands of the rapd between m and the tuber of t8 might revealed that the genetic matter of m did not invade the inter area of gastrodia elata bl 2通过对同一株不同生长时期的天麻与蜜环菌的rapd扩增结果的研究表明:同一株天麻不同生长时期的dna不表现差异,而且与密环菌没有共同的条带,这说明密环菌与天麻的dna有较大的差异,特别是与块茎之间的差异说明密环菌的遗传物质在天麻的生长过程中侵入天麻块茎皮层以内的部位时已被同化。