Effect of Shading and Forest Type on Morphological Characteristics and Bioactive Compounds of Fruiting Bodies of Songshan Lingzhi Ganoderma tsugae (Agaricomycetes)

Ganoderma tsugae strain MCCCMAS0053 cultivation on short logs results in varied yield and quality under different growth conditions. Thus, growth conditions need optimization to increase yield and quality. An indoor experiment with three shade treatments (A1, two layers of black sun-shade net; A2, one layer of black sun-shade net plus plastic mulch; A3, one layer of black sun-shade net) and a field experiment in two forest types (pine or mixed pine-oak) were conducted. The results showed that shading and forest type significantly affected light intensities and the growth, size, biomass, and bioactive components of G. tsugae fruiting bodies. In the indoor experiment, the mean dry weight of the fruiting body and the diameter of the pileus in A2 increased by 21.51-44.98% and 13.42-22.26%, respectively, compared with those of A1 and A3. Similarly, the accumulation of the bioactive compounds (polysaccharides, total amino acids, and total essential amino acids) in the pileus and stipe were greater in A2 than in A1 and A3. Furthermore, compared with pure pine forest cultivation, fruiting bodies cultivated in mixed pine-oak forest had greater dry weight, pileus diameter, and more bioactive compounds. In addition, no significant difference was found between the A2 and mixed pine-oak treatments, which had a similar light intensity (from 1116 to 2367 lx). Hence, this suggests that the A2 shade treatment or cultivation in mixed pine-oak forest is beneficial for production of G. tsugae fruiting bodies, and light intensity may play a critical role in this process.