Effects of Mineral Elements on Fruit-body Yield and Mycelia Growth Rate of Different Colony Types of Cordyceps militaris in Subculturing

Abstract:

To elucidate the relationship among mineral elements, the yield of fruit-body and growth rate of mycelia, effects of mineral elements on the fruit-body yield and growth rate of mycelia of different colony types of Cordyceps militaris in subculturing were investigated. L20, a good strain, was subcultured on different mineral elements media for twelve times with orthogonal experimental method. The results showed that there were seven colony types of L20 after subcultured, among which type Ⅰ, Ⅱ, Ⅲ and Ⅴ had ability to form fruit-body; however, type Ⅳ, Ⅵ and Ⅶ could not. TypeⅠ performed the highest yield of fruit-body, typeⅡ the lowest, and type Ⅲ in mid-level; while all the fruit-body produced by typeⅤ were deformity. The growth rate of mycelia of different colony types were as follow: typeⅤ > typeⅣ > typeⅦ > typeⅥ > typeⅢ > typeⅡ > typeⅠ. The high-production colonies had slower growth rate of mycelia, while the low- production types had over growth of hyphae, indicating there was a negative correlation between the growth of mycelia and fruit-body yield. The formulation of mineral elements, which kept typeⅠhigh yield and maintained more generations was K3Mg2Ca4Mn3Zn2, of which Mn, and K were able to produce high yield of fruit-body; K, Mg and Ca could maintain more generations to produce high yield. The best formulation which suppressed excessive growth rate of mycelia of type Ⅰwas K3Mg2Ca2Mn3Zn2, and Mn had the most significant effect.