Nutrient media and substrate optimization for commercial cultivation of Cordyceps militaris (L.) Fr., a novel medicinal mushroom from Jammu and Kashmir

Cordyceps militaris (L.) Fr., an expensive macrofungus known for its high medicinal value, was collected from wild to study its mycelial growth and stromata production under controlled conditions. The identification of the fungus was confirmed by macroscopic, microscopic and molecular studies. This is the first documented report of the isolation and successful cultivation of wild C. militaris from Jammu and Kashmir, India. The cultivation period of C. militaris up to mature stage (stroma) has been around 2–3 months and there is need to reduce the time period for developing inoculum/spawn and for reducing the cultivation period in order to get more yield of this precious medicinal macrofungus. Therefore, in this study, different media viz., Sabouraud’s dextrose agar (SDA), potato dextrose agar (PDA), corn meal agar (CMA), Richard’s synthetic agar (RSA) alone and in combination with malt extract (ME) and yeast extract (YE) were assessed for their potential to increase the biomass of this fungus. It was cleared from the results that SDA showed the highest mycelial growth followed by PDA, CMA and RSA. Further, in order to reduce the time duration for the maximum mycelial growth on SDA, the media was optimized with two different supplements viz., malt extract and yeast extract and the results showed that maximum mycelial diameter was observed after 17 days of inoculation with media composition of SDA with 6 g/L ME and 4 g/L YE. Further, Cordyceps militaris collected from wild was cultivated on different grain substrates along with two distinct nutritional broths to evaluate its yield and growth characteristics. The findings revealed that the maximum yield was observed on brown rice when supplemented with nutritional broth-Ⅰ followed by corn kernel, white rice and wheat grain. The present investigation provides insights into the optimum culture conditions for mycelial growth and stroma formation. Furthermore, in the present investigation, time for cultivation was minimized that will help to increase yield of this macrofungus but after further investigation.