As a main causal agent of wheat crown rot, Fusarium pseudograminearum secrets numerous proteins into the host during the infection process to regulate host immune responses and contribute to the virulence of F. pseudograminearum.  In this study, the secreted protein Fp00392 from F. pseudograminearum was found to trigger cell death in Nicotiana benthamiana.  Purified Fp00392 protein could activate the ROS burst, callose deposition, and the upregulation of defense-related genes in N. benthamiana.  Moreover, the VIGS assay in N. benthamiana showed that Fp00392-triggered cell death is independent of BAK1 and SOBIR1.  Furthermore, the transcript level of Fp00392 was significantly induced during F. pseudograminearum infection.  Knockout of Fp00392 significantly attenuated the pathogenicity of F. pseudograminearum on wheat coleoptiles.  Deletion of Fp00392 affected the sensitivity of F. pseudograminearum to H₂O₂ and Congo Red.  Overall, these results indicate that Fp00392 can not only induce plant immune response as a PAMP, but it can also promote F. pseudograminearum infection as a virulence factor.

Phosphorus (P) is an essential nutrient element that is critical for plant growth and ecosystem functionality. The soil P cycle plays multiple roles, such as sustaining plant growth and productivity, regulating nutrient balance within ecosystems, and enhancing ecosystem adaptability and resilience. This cycle is influenced by factors such as the restoration approach and microbial community dynamics. However, the extent to which the restoration approach alters the P cycle in karst ecosystems and the underlying microbial mechanisms remain poorly understood. The P-cycle multifunctionality index (P-cycle MFI) serves as a comprehensive indicator for evaluating soil P cycle function, and it provides insights into changes in the P cycle between different restoration approaches. To investigate the shifts in soil P-cycle MFI and microbial mechanisms between different restoration approaches, we analyzed soil available P (AP), total P (TP), microbial biomass P (MBP), and the activities of acid phosphatase (ACP) and alkaline phosphatase (ALP). These data were used to calculate the P-cycle MFI by averaging the Z-scores between two restoration approaches (artificial restoration of forest (AF) and natural restoration of forest (NF)) and a control (cropland, CP) at six subtropical karst ecosystem sites in China. We also determined the soil organic carbon (SOC), exchangeable calcium (Ca) and magnesium (Mg), pH, bulk density (BD), microbial biomass C (MBC), and microbial biomass nitrogen (MBN), as well as the community structure, relative abundance, diversity indices, and co-occurrence networks of phoD-harboring bacteria. The results showed that the community structure of phoD-harboring bacteria varied significantly among AF, NF, and CP and across different temperature gradients. These bacteria exhibited increasing complexity and tightness in co-occurrence networks from CP to AF and then to NF, along with the ACP and ALP activities, but not the TP and AP contents. The P-cycle MFI values were significantly higher in NF compared to AF and CP, and the variation was significantly explained by restoration approach, temperature, MBC, MBN, SOC, exchangeable Ca, BD, community structure of phoD-harboring bacteria, and exchangeable Mg. Furthermore, natural restoration had a more substantial impact on the P-cycle MFI than temperature by enhancing SOC, microbial biomass, the complexity and co-occurrence network tightness of the phoD-harboring bacterial community structure, and ACP and ALP activities, but it reduced soil BD. The rare genera of phoD-harboring bacteria significantly influenced the variation of soil P-cycle MFI compared to the dominant genera. This study highlights the importance of rare genera of phoD-harboring bacteria in driving soil P-cycle multifunctionality in karst ecosystems, with natural restoration being more effective than artificial methods for enhancing soil organic matter and microbial community complexity.

No tillage and stubble retention have emerged as effective measures for restoring land degraded and enhancing ecosystem productivity. However, the underlying mechanism driving productivity improvements is not well understood, particularly in ecological fragile region such as the Loess Plateau of China. To address this knowledge gap, a 22-year long-term field experiment was performed to investigate the changes in soil nutrients, crop and forage productivity, and their driving factors following the implementation of conventional tillage (T), conventional tillage combined with stubble retention (TS), no tillage (NT), and no tillage combined with stubble retention (NTS) within a forage-crop rotation system on the Loess Plateau. The results indicated that TS and NTS treatments significantly increased system productivity by 19 and 32%, respectively, with NTS demonstrating the most pronounced benefits. The NTS increased maize yield, wheat yield and soybean biomass by 19, 14 and 52%, compared to T, respectively. Moreover, the NTS treatment resulted in the highest soil carbon and nitrogen accumulation, enzymes activity and overall soil conditions. Soil carbon and nitrogen storage with NTS was increased by 41 and 53% compared to T in the 0-10 cm soil depth, respectively. The activities of βG (β-glucosidase), CBH (cellobiohydrolase), βX (β-xylosidase), LAP (leucine-aminopeptidase), NAG (β-N-acetylglucosaminidase) in NTS increased by 45, 98, 39, 50 and 53%, respectively. Overall, results demonstrated that no tillage combined with stubble retention increased crop productivity by improving soil carbon and nitrogen fractions, enzymes activity and soil moisture. Soil moisture was the key driver affecting forage biomass, whereas organic carbon input primarily influenced grain production. In conclusion, NTS represents the most appropriate land management practice for optimizing agricultural productivity on the Loess Plateau, while facilitating green and sustainable agricultural development.

Early leaf spot (ELS) is one of peanut’s prominent and widespread foliar fungal diseases, causing severe yield losses and forage quality deterioration in South China. Discovery of the genomic region and the underlying candidate gene controlling ELS resistance will promote progress in resistance breeding and facilitate uncovering its genetic basis. In this study, a major genomic region, qELSB02.1, was identified using a bulked segregant RNA-Seq (BSR-seq) approach in a RIL population derived from a cross between a susceptible cultivar ZH10 and a resistant line ICG12625. It was further confirmed via simple sequence repeat genetic map-based linkage analysis, explaining 20.13-35.27% of the phenotypic variation. Using a partial genetic map and a segregation mapping population, qELSB02.1 was fine-mapped into a 465 kb genomic region by linkage analysis and substitution mapping. Furthermore, an NB-ARC-LRR gene (Arahy.V6I7WA) was identified as the most probable candidate gene for qELSB02.1 and was named Arachis hypogaea ELS resistance 1 (AhELSR1) based on functional annotation, sequence variation analysis, expression profiling, and protein structure prediction. Allelic variation analysis using 244 global peanut germplasm accessions identified four haplotypes, providing valuable clues for understanding ELS resistance evolution mediated by AhELSR1. Five SNPs, located in the first exon of AhELSR1, altering four encoding amino acids, were used to develop a diagnostic marker. The marker was further validated using diverse peanut germplasm and through introgression of AhELSR1 into a susceptible cultivar. Our results provide new insights into the genetic basis of ELS resistance regulation and benefit the breeding efforts for developing improved cultivars with enhanced ELS resistance.