Abstract

This work evaluated the yield of Pleurotus pulmonarius on different mixtures of cotton waste and cassava peel. P. pulmonarius demonstrated significantly higher colonization rate on cotton waste substrate (100 g cotton waste) 3 weeks after inoculation of spawn than any other substrate mixtures. Cotton waste had the shortest time for full mycelial ramification (3 weeks) and mushroom primodial appearance (3¹/₂ weeks). At 7^th week of cultivation, substrate mixtures; 20 g cotton waste + 80 g cassava peel and the cassava peel substrate (100 g) had not ramified, therefore, no appearance of mushroom pinhead. The highest yield was observed on 100 g cotton waste with mushroom yield of 79.4 g followed by 80 g cotton waste + 20 g cassava peel with 72.0 g. Cassava peel (100 g) produced no mushroom fruit. The least mushroom yield of 3.0 g was obtained from the substrate mixture 20 g cotton waste + 80 g cassava peel. The highest number of flushes obtained was 4 recorded for substrate mixtures 70 g cotton waste + 30 g cassava peel, 50 g cotton waste + 50 g cassava peel, 40 g cotton waste + 60 g cassava peel and 100 g cotton waste. The results showed that cotton waste was a better substrate for cultivation of P. pulmonarius than cassava peel. However, with the high availability of cassava peel in Nigeria, the potential use of this waste as substrate adjunct (at 20% of substrate) can be suggested based on the findings of this study. It can be deduced from this study that cassava peel may be used for mushroom cultivation if supplemented with a good nitrogen source.

Key words: Mushrooms, Pleurotus pulmonarius, cotton waste, cassava peel.