Fungal Saprotrophic Promotion and Plant Pathogenic Suppression under Ditch-Buried Straw Return with Appropriate Burial Amount and Depth.

Fungi as heterotrophs are key participants in the decomposition of organic materials and the transformation of nutrients in agroecosystems. Ditch-buried straw return as a novel conservation management strategy can improve soil fertility and alter hydrothermal processes. However, how ditch-buried straw return strategies affect the soil fungal community is still unclear. Herein, a 7-year field trial was conducted to test the influences of burial depth (0, 10, 20, 30, and 40 cm) and the amount of ditch-buried straw (half, full, double) on the diversity, composition, and predicted functions of a soil fungal community, as well as the activities of carbon-degraded enzymes. Under the full amount of straw burial, the abundance of phylum Ascomycota was 7.5% higher as compared to other burial amount treatments. This further increased the activity of cellobiohydrolase by 32%, as revealed by the positive correlation between Ascomycota and cellobiohydrolase. With deeper straw burial, however, the abundance of Ascomycota and ß-D-glucopyranoside activity decreased. Moreover, genus Alternaria and Fusarium increased while Mortierella decreased with straw burial amount and depth. FUNgild prediction showed that plant fungal pathogens were 1- to 2-fold higher, whilst arbuscular mycorrhizal fungi were 64% lower under straw buried with double the amount and at a depth of 40 cm. Collectively, these findings suggest that ditch-buried straw return with a full amount and buried at a depth less than 30 cm could improve soil nutrient cycles and health and may be beneficial to subsequent crop production.

Long-term residue returning increased subsoil carbon quality in a rice-wheat cropping system.

Residue returning (RR) was widely implemented to increase soil organic carbon (SOC) in farmland. Extensive studies concentrated on the effects of RR on SOC quantity instead of SOC fractions at aggregate scales. This study investigated the effects of 20-year RR on the distribution of labile (e.g., dissolved, microbial biomass, and permanganate oxidizable organic) and stable (e.g., microbial necromass) carbon fractions at aggregate scales, as well as their contribution to SOC accumulation and mineralization. The findings indicated a synchronized variation in the carbon content of bacterial and fungal necromass. Residue retention (RR) notably elevated the concentration of bacterial and fungal necromass carbon, while it did not amplify the microbial necromass carbon (MNC) contribution to SOC when compared to residue removal (R0) in the topsoil (0-5 cm). In the subsoil (5-15 cm), RR increased the MNC contribution to SOC concentration by 21.2%-33.4% and mitigated SOC mineralization by 12.6% in micro-aggregates (P < 0.05). Besides, RR increased soil ß-glucosidase and peroxidase activities but decreased soil phenol oxidase activity in micro-aggregates (P < 0.05). These indicated that RR might accelerate cellulose degradation and conversion to stable microbial necromass C, and thus RR improved SOC stability because SOC occluded in micro-aggregates were more stable. Interestingly, SOC concentration was mainly regulated by MNC, while SOC mineralization was by dissolved organic carbon under RR, both of which were affected by soil carbon, nitrogen, and phosphorus associated nutrients and enzyme activities. The findings of this study emphasize that the paths of RR-induced SOC accumulation and mineralization were different, and depended on stable and labile C, respectively. Overall, long-term RR increased topsoil carbon quantity and subsoil carbon quality.

Application of calcium overload-based ion interference therapy in tumor treatment: strategies, outcomes, and prospects.

Low selectivity and tumor drug resistance are the main hinderances to conventional radiotherapy and chemotherapy against tumor. Ion interference therapy is an innovative anti-tumor strategy that has been recently reported to induce metabolic disorders and inhibit proliferation of tumor cells by reordering bioactive ions within the tumor cells. Calcium cation (Ca2+) are indispensable for all physiological activities of cells. In particular, calcium overload, characterized by the abnormal intracellular Ca2+ accumulation, causes irreversible cell death. Consequently, calcium overload-based ion interference therapy has the potential to overcome resistance to traditional tumor treatment strategies and holds promise for clinical application. In this review, we 1) Summed up the current strategies employed in this therapy; 2) Described the outcome of tumor cell death resulting from this therapy; 3) Discussed its potential application in synergistic therapy with immunotherapy.

Cadmium-Tolerant Bacterium Strain Cdb8-1 Contributed to the Remediation of Cadmium Pollution through Increasing the Growth and Cadmium Uptake of Chinese Milk Vetch (Astragalus sinicus L.) in Cadmium-Polluted Soils.

Cadmium (Cd) pollution has attracted global attention because it not only jeopardizes soil microbial ecology and crop production, but also threatens human health. As of now, microbe-assisted phytoremediation has proven to be a promising approach for the revegetation of Cd-contaminated soil. Therefore, it is important to find such tolerant microorganisms. In the present study, we inoculated a bacteria strain tolerant to Cd, Cdb8-1, to Cd-contaminated soils and then explored the effects of Cdb8-1 inoculation on the performance of the Chinese milk vetch. The results showed plant height, root length, and fresh and dry weight of Chinese milk vetch grown in Cdb8-1-inoculated soils increased compared to the non-inoculated control group. The inoculation of Cd-contaminated soils with Cdb8-1 also enhanced their antioxidant defense system and decreased the H2O2 and malondialdehyde (MDA) contents, which alleviated the phytotoxicity of Cd. The inoculation of Cdb8-1 in Cd-contaminated soils attenuated the contents of total and available Cd in the soil and augmented the BCF and TF of Chinese milk vetch, indicating that the combined application of Cd-tolerant bacteria Cdb8-1 and Chinese milk vetch is a potential solution to Cd-contaminated soils.