बैग भरना और कवक जाल का फैलाव

01Filling and spawning the bag

Spawn is the seed material: grain fully covered in mycelium. Use it fresh. Historical publications give age examples, but product, strain, carrier and storage conditions differ. Use traceable supplier guidance and receiving checks; these examples are not a universal expiry rule.

The manual mixes spawn at 2-3 per cent of wet substrate weight; one 300 g bottle serves 10-12 kg of wet straw. The folder says about 100 g per 4 kg wet straw.

Bag sizes differ by institute: the folder uses 40-45 by 30-35 cm polythene; the manual 60 x 45 cm of 125-150 gauge; TNAU 60 x 30 cm of 80 gauge. Follow the chosen bag system's opening and drainage method. Holes do not guarantee a safe substrate temperature; check conditions with suitable measurements.

02What a spawn run needs, and what it does not

Mycelium grows between 10 and 30 C, best at 22-26 C. Above 30 C in the room it stops and dies, and the bag runs 2-4 C warmer than the room. If the bag climbs past 30 C, the folder says to splash water on walls and roof two or three times a day or run an air cooler.

The folder is blunt: during the run the bags need no water, no air and no light. The manual agrees: bags stay closed, no ventilation, no spraying. The mycelium tolerates carbon dioxide up to about 2 per cent, so a closed dark room is fine. TNAU instead asks for 22-25 C with 85-90 per cent humidity in a dark shed.

03Reading the bag day by day

Days 1-5: white threads spread from each grain. Days 5-12: threads meet and the straw colour fades. The folder expects the whole bag white in 15-25 days. The manual sets a hard rule: never open before 16-18 days, except P. membranaceus and P. djamor var. roseus, which fruit through the holes within 10 days.

Trouble signs: green patches (Trichoderma), black spots, a sour smell, or a wet grey mass at the bottom from excess water. Slow, thin growth points to cold or old spawn. A bag hot to the palm is packed too tight or the room is too warm. Remove a contaminated bag at once and bury it in a deep pit away from the room.

04Space, flies and hygiene

Stack loosely. The manual sets 15-20 cm between bags so heat escapes; tight stacks push centre bags over 30 C. Racks with a gap under each bag drain better than a floor pile.

NHB repeats the ICAR advice to screen doors and ventilators with nylon net of 35 mesh or finer so flies cannot lay eggs in the bags. Keep the room closed; the manual wants it pre-fumigated before spawning and a closed room stays that way.

Work from clean to dirty: good bags first, suspect bags last, wash hands between. The diary tells you next batch whether the straw, the spawn or the room was at fault.