Abstract:
Most developing countries like Ethiopia are striving hard to solve acute protein deficiency in the diets
of their increasing populations through cultivation of mushrooms in the urban areas without heavily
depending on agricultural lands and capital. This study was conducted in Debre Berhan University,
College of Natural and computational Sciences, with the aim of assessing the proximate chemical
composition, biological efficiency and suitability of the selected substrates (Millet straw and Broad
bean stalk) according to the methods described in AOAC (1995) for oyster mushroom cultivation.
Accordingly, broad bean stalk and millet straw, and their different mix ratios were tested for their
efficacy in oyster mushroom production. The spawns of oyster mushrooms were obtained from the
Mushroom Research, Production and Training Laboratory of Haramaya University, College of
Agriculture. The spawn production sorghum was separately inoculated with the pure cultures oyster
mushroom and later on transferred to selected agricultural wastes (i.e. broad bean stalk and millet straw) for the production of fruiting bodies. The oyster mushroom cultivation was undertaken under
aseptic conditions and growth and development was monitored daily. Results of the study revealed
that oyster mushroom can grow on broad bean stalk and millet straw with varying growth
performances. The highest percentage of biological efficiency was obtained from S2(50%millet straw
+50%broad bean stalk) for Pleurotus ostreatus (P.o) and from S5(100%broad bean stalk) for
Pleurotus florida (P.f), while the least was from S5 (100%broad bean stalk) for Pleurotus ostreatus
and from S1(75%millet straw+25%broad bean stalk) for Pleurotus florida. The maximum protein for
Pleurotus ostreatus and Pleurotus florida was obtained from S4(100%millet straw) and the
minimum for Pleurotus ostreatus from S3(25%millet straw+75%broad bean stalk) and for Pleurotus
florida from S1(75%millet straw+25%broad bean stalk) respectively. The highest fiber for Pleurotus
ostreatus and Pleurotus florida was gained from S4 (100%millet straw), and the least for
Pleurotus ostreatus from S3 (25%millet straw+75%broad bean stalk) and for Pleurotus florida from
S1 (75%millet straw+25%broad bean stalk) respectively. S4 (100%millet straw) was the most
decomposable substrate than others. The nutritive values of the studied mushrooms were quite very
high, and the selected growth substrates were reasonably acceptable.
