Abstract: To investigate the effects of different spawn application rates on the yield and agronomic traits of Stropharia rugosoannulata, three spawn application rates were established: D1 (0.8 kg/m²), D2 (1.6 kg/m²), and D3 (2.4 kg/m²). The objective was to determine the effects of different spawn application rates on yield and agronomic traits, as well as the differences in agronomic traits of fruiting bodies among different flushes. The results showed that different spawn application rates affected the fruiting time and fruiting cycle of Stropharia rugosoannulata. Under higher spawn application rates, the fruiting time was shorter, while the fruiting cycle was longer. Specifically, treatment D1 had the longest fruiting time of 60 d and the shortest fruiting cycle of 54 d, whereas treatment D3 had the shortest fruiting time of 43 d and the longest fruiting cycle of 72 d. The yield of Stropharia rugosoannulata increased with increasing spawn application rate. The total yields of the D2 and D3 treatments were significantly higher than that of the D1 treatment, whereas no significant difference was observed between the D2 and D3 treatments. In all three treatments, the second flush accounted for the highest proportion of yield, ranging from 44.28% to 52.79%. With the increase in flush number, the proportion of low-value mushrooms (individual weight < 20 g) increased from 8.30%-26.06% in the first flush to 69.52%-76.54% in the third flush. In terms of agronomic traits, no significant differences were observed among different spawn application rates in individual mushroom weight, fruiting body length, stipe length, stipe diameter, or pileus diameter. However, the mushroom shape index differed significantly, with D1 being significantly higher than D2 and D3. Regarding the coefficients of variation of fruiting body agronomic traits, individual mushroom weight showed the largest coefficient of variation, with an overall value of 72.51%, whereas the mushroom shape index showed the smallest coefficient of variation, at 28.65%. The coefficients of variation for fruiting body length, stipe length, stipe diameter, and pileus diameter ranged from 29.69% to 33.29%. Overall, the fruiting body traits of the first flush under the D3 treatment performed best, with fruiting body length, stipe length, and pileus diameter.

Key words: Stropharia rugosoannulata, spawn application rate, yield, agronomic traits, coefficient of variation