The use of supplementation in the compost is well established in the mushroom industry since early 1970’s. Most have been based on the use of high protein supplements (Carroll & Schisler) using formaldehyde to denature it and giving it delay release characteristics. 

Later Parker (1991) developed a variant on this using natural carboxylic acid salts to coat the feed particles which gave similar delay release mechanism. From this original work, Parker and Whitehall (2009) determined that the limiting factor in nutrition was its availability and this has become more apparent with ever shortening crop cycles. In 2013 with company Nutrigain they developed (and patented) a liquid supplement that can be applied to the top of the compost before casing called Mycrofeeder. 

This zone is where a lot of feeding activity occurs and this is why an easily available nutrient source was developed to ‘feed’ the mycelium during the case run. The time period is short, so optimal temperature conditions for enzymatic feeding is very important. Of important note is the maintaining the density and shape of mushroom through the flush and minimising quality loss on the later picking days. Growers observe this when they test the Mycrofeeder.

 If mushroom is heavier and grade mix is better for longer, it follows through that yields should be higher. With increasing labour costs all over the world, it is pointless increasing yield if the grower cannot increase the individual weight of each mushroom and therefore tackle reducing the largest variable cost in growing. Material and Methods Phase 3 compost: Tunneltech North Ltd. Casing McDon Peat. Spawn Triple X. Compost was removed from blocks and mixed together to homogenise. Compost was measured out two 7kg lots and put into a plastic growing tub with appropriate treatment as below with replicate. Casing supplement Mycroliquid (220ml/m 2 ) and interface Mycrofeeder (200ml/m 2 ). The compost is lightly pressed and casing added to a depth of 50mm. We additionally tested the casing supplement Mycroliquid on the interface to compare with Mycrofeeder.

Casing is watered with 2L/m 2 water and plastic bag applied to prevent moisture loss and build up CO2 during the case run. Temperature in compost is controlled to 24-25C during this period. After 5 days the plastic is removed and 2 waters of 2L/m 2 are added to the casing whilst maintaining warm air temperature 22C.

 Airing is made on day 6. Visual observations made throughout whole crop. Picked mushrooms are untrimmed weight. We estimate effect of this is approximately 10% inflation in yield figure compared to trimmed. 

There are 2 tables of results; one with and one without casing/interface products. The tables are then laid out as follows; along the top are flush and flush totals and down the side are the treatments. Numbers in black are yield (untrimmed), red are average weight of each mushroom in grams and green is % increase in yield on control i.e. nothing in compost and nothing in the casing.