Abstract:

To investigate the effects of different cultivation substrates on the agronomic traits and quality of Lepista sordida, a formula cultivation experiment was conducted using the 'E70' strain of L. sordida. Five cultivation formulas (designated as A, B, C, D and E), were set up with wheat straw, corncob, cottonseed hull, and rice straw as the main cultivation substrates respectively. L. sordida was cultivated by the method of one-time fermented material bed cultivation. After the fruiting bodies formed, the agronomic traits and nutritional components of the fruiting bodies were determined to evaluate the impacts of fermented materials with different formulas on the agronomic traits and quality of L. sordida. The results showed that there were significant differences in yield, morphology, color and nutritional components of L. sordida among the five cultivation formulas. The biological efficiency of D (corncob 50% + dry cow dung 26% + husk 20% + lime 2% + gypsum 2%) was (46.73±0.15)%, which was significantly or extremely significantly higher than that of other formulas. Comprehensive assessment revealed that the fruiting bodies grown with D exhibited the optimal marketability, characterized by the highest yield, thickest stipe, small pilei, and purple color. The fruiting bodies of L. sordida in the five groups were rich in protein, polysaccharides, and amino acids. Specifically, protein of B (corncob 60% + dry cow dung 36% + lime 2% + gypsum 2%) was 36.70 g/100g; while the polysaccharide of D was 4.76 g/100g, which was 2.44 times that of A (straw 56% + corncob 28% + bran 8% + rapeseed cake 5% + lime 2% + gypsum 1%). The composition of taste amino acids followed the descending order of umami amino acids > bitter amino acids > sweet amino acids > aromatic amino acids. Notably, the umami amino acids of L. sordida in E (rice straw 50% + dry cow dung 26% + husk 20% + lime 2% + gypsum 2%) all exceeded the taste threshold, with a total content of 13.6 g/100g, representing 13.14% increase compared with A, respectively. The sweet amino acid content in C (cottonseed hull 56% + corncob 20% + bran 20% + lime 2% + gypsum 2%) reached 7.41 g/100g, 21.87% rise relative to D. The aspartic acid content in D was 2.7 g/100g, which was 90 times higher than its taste threshold. The glutamic acid content in E hit 6.3 g/100g, 126-fold higher than its taste threshold. Meanwhile, the SRCAA (Sorce of Ratio of Commonly Used Amnio Acids) value of amino acids in D was 68.56, suggesting that this formula had the most balanced proportion of essential amino acids among all test groups. The RCAA (Ratio of Commonly Used Amino Acids) value of methionine in all five formulas was the lowest (all<1), confirming that methionine is the first limiting amino acid of L. sordida. Formula D is the optimal formula for large-scale cultivation of L. sordida 'E70' strain. The results of this study provide a scientific basis for the research and development of standardized cultivation techniques and industrial promotion of L. sordida. In the future, multi-strain adaptation and cultivation process optimization can be further studied.

Key words: Lepista sordida, cultivation substrate, agronomic traits, nutritional analysis, polysaccharides, amino acids, amino acid evaluation analysis