Effect of Adding Selenium to the Malt-Yeast-Agar Medium on the Mycelium Growth of the Mother Culture of Agaricus bisporus

This study was carried out at Set-markho facility, Latakia, Syria, for the production of agricultural mushroom (Agaricus bisporus) during the period 2022-2023, in order to study the effect of adding selenium to the growth medium on the mycelium growth of the mother culture (G0). The experiment included five treatments as follows: control, adding selenium at four concentrations of 1, 0.1, 0.01 and 0.001 mg/L to the malt-yeast-agar medium. Results obtained showed that all selenium treatments were superior to the control at the beginning of mycelium growth, whereas two selenium concentrations (0.001 and 0.01 mg/L) treatments were significantly superior to the control and the rest of selenium treatments, in terms of the average fungal colony diameter, which reached 75.2 and 62.2 mm, respectively, and the time required to complete mycelium growth on the culture medium was 23 days for each treatment, and the average growth rate recorded was 3.27 and 2.7 mm/day, respectively. In addition, the average growth coefficient was 22.88 and 18.93 mm2/day, respectively. Accordingly, the agricultural mushroom Agaricus bisporus was classified as a slow-growing fungus. Keywords: Agaricus bisporus, selenium, mother culture, growth.