Research on the stipe cracking of wine-cap mushroom (Stropharia rugosoannulata) in different humidity conditions

Stropharia rugosoannulata is a well-renowned edible mushroom due to its nutritional and nutraceutical properties. This article focuses on the study of stipe cracking in S. rugosoannulata, a common issue in outdoor cultivation of this mushroom in South China. The findings reveal that the stipe cracks of S. rugosoannulata are primarily horizontal (transverse). Typically, cracks appear between the annulus and the middle part of the stipe prior to the opening of the pileus. Following the opening of the pileus, a fresh crack appears on the upper part of the stipe above the annulus. During the growth of S. rugosoannulata, two distinct elongation sections are observed in the stipe, separated by the annulus. The location of cracks coincides with these elongation sections, and the sequence of crack occurrences matches with the sequence of these elongation sections. The frequency of stipe cracking varies according to developmental stages and humidity conditions. The conclusion of this study is that S. rugosoannulata stipes crack during elongation and within elongation sections when humidity is low (≤ 60%), with the S3 developmental stage having the highest risk of cracking.