Artificial Cultivation of the Chinese Cordyceps From Injected Ghost Moth Larvae

Abstract

The Chinese cordyceps, regarded as the ‘Himalayan Viagra’, is highly valued for its medicinal benefits. The decline of its yield due to over-exploitation and increased market demand have stimulated efforts to artificially cultivate Chinese cordyceps for over half a century. However, successful cultivation of Chinese cordyceps through caterpillar infection by the fungus Ophiocordyceps sinensis (Berk.) and the induction of the fruiting body from each mummified cadaver remains difficult for its complex life cycle. Herein, we report the developmental dynamics of hyphal bodies in hemolymph of injected Thitarodes xiaojinensis (Tu, Ma & Zhang) larvae and the success in artificial cultivation of sexual fruiting bodies from the mummified cadavers in the low-altitude area. We find that not only the numbers of hyphal bodies but also the conversion of hyphal bodies into hyphae played important roles in the mummification of the injected larvae. This cultivation will be beneficial for sustainable utilization of natural resources and provides the possibility for further research on the mechanism of the interaction between pathogenic fungus and host insect.

Quorum Sensing Activity and Hyphal Growth by External Stimuli in the Entomopathogenic Fungus Ophiocordyceps sinensis

“…Blastospores-hyphae transition is related to fungal pathogenicity and virulence to mammals, plants, and insects [23], and the connection between the blastospores-hyphae transition and the virulence of O. sinensis fungus to host insect larvae is also observed [14]. It is necessary to explore the factors involved in blastospores-hyphae dimorphism, to regulate the mummification process during the artificial cultivation of the Chinese cordyceps.…”

“…However, the low mummification rate post-infection is still an unresolved obstacle for commercial cultivation of the Chinese cordyceps [11][12][13]. O. sinensis could colonize the larva's hemocoel for more than one year without killing the host larva if the blastospores do not turn into a differentiation phase to form invasive hyphae [14]. Compared with other entomopathogenic fungi, such as Metarhiziurn anisopliae and Beauveria bassiana, which cause the death of host larvae within a few days [15][16][17], O. sinensis took a long time to kill its host larvae.…”

“…Like species within the genera Beauveria, Metarhizium, and Isaria [18], O. sinensis also exhibits an in vivo dimorphic developmental process [14]. The blastospores grow exponentially by budding growth in the hemocoel without apparent damage to the host larva.…”

Analysis of Volatile Components in Different Ophiocordyceps sinensis and Insect Host Products

“…Artificial cultivation of fruiting bodies on rice media [6] or whole Chinese cordyceps by challenging T. xiaojinensis larvae with O. sinensis fungus [7,8,11] were established in low altitude Guangzhou, with mimicking environmental conditions. The insect species was identified using a molecular method by the amplification of the Cytochrome b sequences with the primers CB1 (TATGTACTACCATGAGGACAAATATC) and CB2 (ATTACACCTCCTAATTTATTAGGAAT) [46], as described previously [47,48].…”

“…Mycelial products of O. sinensis fungus have also been manufactured by fermentation technology [9]. More excitingly, the success of cultivation on a large scale has been achieved recently in China [10,11].…”