The black morel Morchella sextelata (Morchellaceae, Pezizales) is a valuable edible mushroom that can be cultivated on a large scale, but a severe yield decline is observed during continuous cropping. The effect of long-term cropping on soil-borne diseases and the dysbiosis of the microbiome and how these biotic factors affect the morel yield are not well understood. To help fill this knowledge gap, we designed an indoor experiment to investigate the influence of black morel cropping regimes on soil physicochemical properties, richness and distribution of fungal community, and morel primordial production. In this study, we employed rDNA metabarcoding and microbial network analysis to evaluate the effect of non-continuous and continuous cropping regimes on the fungal community during three developmental stages of black morel production, namely, the bare soil mycelium, mushroom conidial, and primordial stages. The results showed that during the first year, M. sextelata mycelium overwhelmed the resident soil fungal community by reducing the alpha diversity and niche breadth of soil fungal patterns by a greater amount compared to the continuous cropping regime, leading to high crop yield of 12.39 ± 6.09/quadrat but less complex soil mycobiome. To sustain continuous cropping, exogenous nutrition bags and morel mycelial spawn were consecutively added to the soil. The additional nutrient input stimulated the growth of fungal saprotrophic decomposers. The degrading activity of soil saprotrophs, including M.sextelata, caused a significant increase in soil nutrient content. This led to an inhibitory effect on the formation of morel primordia, resulting in a sharp decline to 0.29 ± 0.25/quadrat and 0.17 ± 0.24/quadrat, respectively, in the final morel cropping. Our findings provided a dynamic overview of the soil fungal community during morel mushroom production, allowing us to identify beneficial and detrimental fungal taxa in the soil mycobiome involved in morel cultivation. The information acquired from this study can be applied to mitigate the adverse impact of continuous cropping on the yield of black morel.

The successful large-scale cultivation of morel mushrooms (Morchella sextelata) requires a comprehensive understanding of the soil bacterial communities associated with morel-farming beds, as the interactions between fungi and bacteria play a crucial role in shaping the soil microbiome. In this study, we investigated the temporal distribution and ecological characteristics of soil bacteria associated with morel fruiting bodies at different stages, specifically the conidial and primordial stages, under two cropping regimes, non-continuous cropping (NCC) and continuous cropping (CC). Our findings revealed a significant reduction in the yield of morel primordia during the third year following 2 years of CC (0.29 ± 0.25 primordia/grid), in comparison to the NCC regime (12.39 ± 6.09 primordia/grid). Furthermore, inoculation with morel mycelia had a notable impact on soil bacterial diversity, decreasing it in the NCC regime and increasing the number of generalist bacterial members in the CC regime. The latter regime also led to the accumulation of nutrients in the soil beds, resulting in a shift from a stochastic to a deterministic process in the composition of the bacterial community, which differed from the NCC regime. Additionally, mycelial inoculation had a positive effect on the abundance of potential copiotrophic/denitrifying and N-fixing bacteria while decreasing the abundance of oligotrophic/nitrifying bacteria. Interestingly, this effect was more pronounced in the NCC regime than in the CC regime. These results suggest that the increase in potential copiotrophic/denitrifying and N-fixing bacteria facilitated the decomposition of nutrients in exogenous nutrient bags by morel mushrooms, thereby maintaining nitrogen balance in the soil. Overall, our study provides valuable insights into the interactions between morel mycelia and the associated soil bacteriome as well as the influence of different cultivation regimes on these interactions. These findings contribute to our understanding of the complex dynamics of the soil microbiome and can inform strategies for optimizing morel mushroom cultivation.

Continuous cropping obstacles (CCOs) have increasingly become an important phenomenon affecting morel mushroom yield and quality. In this review, we summarize the current knowledge about the driving factors behind morel mushroom continuous cropping, including the increase in soil nutrients, disorder of the soil microbial structure, aggravation of diseases, and accumulation of allelochemicals and autotoxins. Furthermore, we analyze the interrelationships among these driving factors. To mitigate these adverse effects, we propose five potential strategic approaches aimed at optimizing existing interventions. This overview not only delineates the causative agents and their intricate interactions under continuous cropping scenarios but also consolidates prospective solutions to alleviate these constraints, thereby advancing our understanding and management of morel production sustainability.

Hafnia alvei is a facultative and rod-shaped gram-negative bacterium that belongs to the Enterobacteriaceae family. Although it has been more than 50 years since the genus was identified, very little is known about variations among Hafnia species. Diversity in O-antigens (O-polysaccharide, OPS) is thought to be a major factor in bacterial adaptation to different hosts and situations and variability in the environment. Antigenic variation is also an important factor in pathogenicity that has been used to define clones within a number of species. The genes that are required to synthesize OPS are always clustered within the bacterial chromosome. A serotyping scheme including 39 O-serotypes has been proposed for H. alvei, but it has not been correlated with known OPS structures, and no previous report has described the genetic features of OPS. In this study, we obtained the genome sequences of 21 H. alvei strains (as defined by previous immunochemical studies) with different lipopolysaccharides. This is the first study to show that the O-antigen gene cluster in H. alvei is located between mpo and gnd in the chromosome. All 21 of the OPS gene clusters contain both the wzx gene and the wzy gene and display a large number of polymorphisms. We developed an O serotype-specific wzy-based suspension array to detect all 21 of the distinct OPS forms we identified in H. alvei. To the best of our knowledge, this is the first report to identify the genetic features of H. alvei antigenic variation and to develop a molecular technique to identify and classify different serotypes.

To investigate the comparison of efficacy evaluation value for cell-free DNA (cfDNA) and CEA in advanced colorectal cancer. A total of 40 patients with advanced colorectal cancer were enrolled in this study. By PCR Real-time, changes of plasma ALU247and ALU115 level as well as the cfDNA integrity (ALU247/ALU115) before and after chemotherapy were analyzed in patients with advanced colorectal cancer. Meanwhile, changes of CEA before and after chemotherapy were monitored to compare the efficacy evaluation value of cfDNA and the conventional CEA in the treatment of advanced colorectal cancer. After first-line chemotherapy, levels of ALU247, ALU115, and ALU247/ALU115 were significantly decreased (p < 0.05) in the respond groups from that of baseline, the same for CEA (p < 0.05). Levels of ALU115 and ALU247 and ALU247/ALU115 (p > 0.05) as well as CEA (p > 0.05) were not changed in stable groups compared with the baseline. In the progression group, however, levels of ALU247 and ALU247/ALU115 were significantly higher than baseline (p < 0.05), and CEA was also higher than that of baseline, but without statistical significance (p > 0.05). ROC curves showed that cfDNA integrity (ALU247/115) and CEA could be used as powerful indicators of outcome assessment. Both cfDNA and CEA are closely related to the evaluation of the first-line chemotherapy for advanced colorectal cancer. The level and integrity of cfDNA are expected to be sensitive indicators for monitoring the efficacy of colorectal neoplasm treatment and earlier clues for tumor progression than CEA.

Premise of the study: To investigate genetic diversity and structure, microsatellite markers were developed and characterized for Cypripedium tibeticum, an endangered orchid species, and their utility tested in two relatives: C. flavum and C. bardolphianum. Methods and Results: Candidate microsatellite loci were isolated based on next‐generation sequencing. We identified 20 polymorphic loci with di‐ or trinucleotide repeats in three populations of C. tibeticum. Genotyping results showed the total number of alleles per locus varied from two to 21, and the observed and expected heterozygosity ranged from 0.261 to 0.967 and 0.441 to 0.960, respectively. Cross‐species amplification showed most of the markers were applicable to C. flavum and C. bardolphianum. Conclusions: The 20 polymorphic microsatellite markers developed in this study are useful tools for studying the conservation genetics and phylogeography of C. tibeticum and its related species.