Table 3.

Effect of compost inorganic nitrogen sources on mushroom yield in experiments conducted in medium- and large-scale facilities (> 1 tonne compost)

N source	N	Inclusion, %*		Yield, % of control		Control compost	Reference
	% w/w	Min	Max	@ Min	@ Max
Ammonium nitrate	35	0.37	0.72	99–116	113–129	Horse manure	(Riethus 1962)
Ammonium sulphate	21.2	0.12		136		Horse and poultry manures	(Riber Rasmussen 1965)
Ammonium sulphate		0.27 N	0.40 N	134	117	Horse manure	(MacCanna 1969)
Ammonium sulphate		0.4		100–105		Horse and poultry manures	(Gerrits 1977a)
Ca ammonium nitrate	27	0.7		108		Horse manure	(Gerrits 1977b)
Calcium nitrate	17	0.27 N	0.40 N	107	86	Horse manure	(MacCanna 1969)
Urea	46.7	0.17–0.66	0.83	58–112	12	Horse manure	(Riethus 1962)
Urea		0.57		75		Horse manure	(Bech and Riber Rasmussen 1969)
Urea		0.35		100–105		Horse manure	(Gerrits 1977b)
Urea		50 N		79		Straw, poultry manure	(Noble et al. 2002)
Urea formaldehyde	38.9	0.68		49		Horse manure	(Bech and Riber Rasmussen 1969)
Urea formaldehyde		0.27 N	0.40 N	107	105	Horse manure	(MacCanna 1969)

* - % w/w of fresh weight or total nitrogen content of N sources (N)