Supplementation of 2nd break mushroom compost with isoleucine, leucine, valine, phenylalanine, Fermenten® and SoyPlus®

Abstract

Three mushroom (Agaricus bisporus) crops (Crops 1, 2, 3) were grown to evaluate the effects of re-supplementing “spent” mushroom compost (MC) with the crystalline amino acids isoleucine (ile), leucine (leu), valine (val) and phenylalanine (phe) singly or in combination with Fermenten® or SoyPlus® on mushroom yield. Fermenten® is a rumen fermentation enhancer while SoyPlus® is a commercial delayed release mushroom nutrient. The most important single amino acid found for stimulating mushroom yield from 2nd break MC was ile. Crystalline ile added to 2nd break MC at 3.6% (dry wt) increased mushroom yields by 28.3% and 68.7% (average 48.5%) in Crops 1 and 2, respectively, compared to the non-supplemented control. In Crop 3, the addition of 5% or 10% ile to Fermenten® and SoyPlus® (3.6% total combined dry wt) did not significantly improve mushroom yield over treatments containing Fermenten® or SoyPlus® (3.6% total dry wt) alone. However, mixtures of equal quantities of Fermenten®, ile and val significantly increased yield over Fermenten® alone. Use of ile and val as supplements to stimulate mushroom yield from 2nd break MC is not economically viable because these amino acids are not commercially available at feed grade prices.