Morel is a popular edible mushroom with considerable medicinal and economic value which has garnered global popularity. However, the increasing heavy metal (HM) pollution in the soil presents a significant challenge to morels cultivation. Given the susceptibility of morels to HM accumulation, the quality and output of morels are at risk, posing a serious food safety concern that hinders the development of the morel industry. Nonetheless, research on the mechanism of HM enrichment and mitigation strategies in morel remains scarce. The morel, being cultivated in soil, shows a positive correlation between HM content in its fruiting body and the HM content in the soil. Therefore, soil remediation emerges as the most practical and effective approach to tackle HM pollution. Compared to physical and chemical remediation, bioremediation is a low-cost and eco-friendly approach that poses minimal threats to soil composition and structure. HMs easily enriched during morels cultivation were examined, including Cd, Cu, Hg, and Pb, and we assessed soil passivation technology, microbial remediation, strain screening and cultivation, and agronomic measures as potential approaches for HM pollution prevention. The current review underscores the importance of establishing a comprehensive system for preventing HM pollution in morels.
Biochar (BC) and organic fertilizers (OFs) are both organic soil amendments that can be used to improve soil quality, but their effects on soil physicochemical properties and microbial structures may be different. Comparative studies can help us understand the advantages and disadvantages of different types of soils. In the current research, five treatments, including a control group (CK), two concentrations of biochar (2% BC and 4% BC), and two concentrations of organic fertilizer (2% OF and 4% OF) and their effects on soil properties, enzyme activities, and bacterial diversity were evaluated. The BC and OF significantly increased the soil EC, pH, and soil nutrients (p < 0.05). The 2% BC increased the biomass of Pennisetum giganteum by 41.7%. The 4% BC and OF reduced the biomass of P. giganteum. Furthermore, the observed decrease in the P. giganteum yield following the application of the 4% BC can be attributed to reductions in the available phosphorus (AP) and CaCl2-P, as well as alterations in the soil enzyme activity. However, the negative impact of OFs on crop yield may be associated with an increased EC, elevated abundance of soil-borne pathogens, and decreased levels of beneficial microorganisms. In summary, a comparative study of the effects of BC and OF on the growth of P. giganteum in acidic soil is of great significance for improving the soil quality, promoting the development of organic agriculture, protecting the environment, and promoting land reclamation.