Composting Spent Mushroom Substrate from Agaricus bisporus and Pleurotus ostreatus Production as a Growing Media Component for Baby Leaf Lettuce Cultivation under Pythium irregulare Biotic Stress

Composts of spent mushrooms substrates can be an alternative for the partial replacement peat as growing media in horticulture. Three mature composts from Agaricus bisporus (Ag), Pleurotus ostreatus (Pl), and 70% Ag:30% Pl (AgPl) production were used components media, at a 1:4 compost:peat ratio red baby leaf lettuce. They showed higher yields, between 3 7 times more than that itself, even under pressure plant pathogen Pythium irregulare. AgPl suppressiveness (50%) against irregulare Ag- (38%) or Pl- (15%) supplemented media. The combination these raw materials suitable composting process is important obtaining compost use component peat-based