Adsorbate-Induced Structural Evolution of Pd Catalyst for Selective Hydrogenation of Acetylene

ACKNOWLEDGMENT: This work was financially supported by National Natural Science Foundation of China (21908002), project funded by China Postdoctoral Science Foundation (2019M660416, 2020T130045) and the Fundamental Research Funds for the Central Universities (buctrc201921, JD2004, XK1802-6). We would like to thank the UK catalysis Hub for help collecting the XAS.Peer reviewedPostprin

Application of Sodium Silicate Enhances Cucumber Resistance to Fusarium Wilt and Alters Soil Microbial Communities

Exogenous silicates can enhance plant resistance to pathogens and change soil microbial communities. However, the relationship between changes in soil microbial communities and enhanced plant resistance remains unclear. Here, effects of exogenous sodium silicate on cucumber (Cucumis sativus L.) seedling resistance to Fusarium wilt caused by the soil-borne pathogen Fusarium oxysporum f.sp. cucumerinum Owen (FOC) were investigated by drenching soil with 2 mM sodium silicate. Soil bacterial and fungal community abundances and compositions were estimated by real-time PCR and high-throughput amplicon sequencing; then, feedback effects of changes in soil biota on cucumber seedling resistance to FOC were assessed. Moreover, effects of sodium silicate on the growth of FOC and Streptomyces DHV3-2, an antagonistic bacterium to FOC, were investigated both in vitro and in the soil environment. Results showed that exogenous sodium silicate enhanced cucumber seedling growth and resistance to FOC. In bare soil, sodium silicate increased bacterial and fungal community abundances and diversities. In cucumber-cultivated soil, sodium silicate increased bacterial community abundances, but decreased fungal community abundances and diversities. Sodium silicate also changed soil bacterial and fungal communality compositions, and especially, decreased the relative abundances of microbial taxa containing plant pathogens but increased these with plant-beneficial potentials. Moreover, sodium silicate increased the abundance of Streptomyces DHV3-2 in soil. Soil biota from cucumber-cultivated soil treated with sodium silicate decreased cucumber seedling Fusarium wilt disease index, and enhanced cucumber seedling growth and defense-related enzyme activities in roots. Sodium silicate at pH 9.85 inhibited FOC abundance in vitro, but did not affect FOC abundance in soil. Overall, our results suggested that, in cucumber-cultivated soil, sodium silicate increased cucumber seedling resistance to Fusarium wilt by changing soil microbial communities rather than by directly inhibiting the growth of FOC

Removal of Dominant Species Impairs Nitrogen Utilization in Co-Existing <i>Ledum palustre</i> and <i>Vaccinium uliginosum</i> Communities Subjected to Five-Year Continuous Interruptions

Unguided exploitation has impaired the sustainability of natural resources of agronomic non-wood forest plants from understory boglands in boreal forests. The extreme consequences of plant–soil interplay on medicinal plant communities under continuous interruptions need to be understood to implement strategies which can cope with possible ecological degradation. In this study, co-existing Ledum palustre and Vaccinium uliginosum communities were investigated after a four-year interruption of continuous removal of dominant species in stands at Xing’an Mountain. Nitrogen (N) availability was assessed by above-ground biomass and N content in nondominant plants and the biophysiological properties of rhizosphere soil. The removal treatment promoted soil mineral and organic N contents, but also reduced abundances of the soil communities of Rozellomycota phylum (by 82.76%), ericoid mycorrhiza of Meliniomyces varia (by 81.60%) and Phialocephala fort (by 69.54%). Vaccinium uliginosum overcame L. palustre through higher N utilization (biomass/%N) although the latter had higher abundances of soil Odiodendron maius and P. fort. The microbial community attributes accounted for a large proportion of N availability following the removal of dominance. In conclusion, our study demonstrates that understory agronomic plants in northern boglands should no longer be under continuous exploitation. Strategies should be considered to improve the promotion of N uptake by managing local soil microbial communities

Comparative Transcriptome Analysis and Genetic Methods Revealed the Biocontrol Mechanism of Paenibacilluspolymyxa NSY50 against Tomato Fusarium Wilt

Fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici (Fol) is a common disease that affects tomatoes, which can cause the whole plant to wilt and seriously reduce the production of tomatoes in greenhouses. In this study, the morphological indexes, photosynthetic performance and incidence rate of NSY50 under Fol infection were evaluated. It was found that NSY50 could improve the growth of tomato seedlings and significantly reduce the incidence rate of Fusarium wilt. However, the molecular mechanism of NSY50 that induces resistance to Fusarium wilt is still unclear. We used transcriptomic methods to analyze NSY50-induced resistance to Fol in tomatoes. The results showed that plant defense related genes, such as PR and PAL, were highly expressed in tomato seedlings pretreated with NSY50. At the same time, photosynthetic efficiency, sucrose metabolism, alkaloid biosynthesis and terpene biosynthesis were significantly improved, which played a positive role in reducing the damage caused by Fol infection and enhancing the disease tolerance of seedlings. Through transgenic validation, we identified an important tomato NAC transcription factor, SlNAP1, which was preliminarily confirmed to be effective in relieving the detrimental symptoms induced by Fol. Our findings reveal that P. polymyxa NSY50 is an effective plant-growth-promoting rhizosphere bacterium and also a biocontrol agent of soil-borne diseases, which can significantly improve the resistance of tomato to Fusarium wilt

Removal of Dominant Species Impairs Nitrogen Utilization in Co-Existing Ledum palustre and Vaccinium uliginosum Communities Subjected to Five-Year Continuous Interruptions

Unguided exploitation has impaired the sustainability of natural resources of agronomic non-wood forest plants from understory boglands in boreal forests. The extreme consequences of plant&ndash;soil interplay on medicinal plant communities under continuous interruptions need to be understood to implement strategies which can cope with possible ecological degradation. In this study, co-existing Ledum palustre and Vaccinium uliginosum communities were investigated after a four-year interruption of continuous removal of dominant species in stands at Xing&rsquo;an Mountain. Nitrogen (N) availability was assessed by above-ground biomass and N content in nondominant plants and the biophysiological properties of rhizosphere soil. The removal treatment promoted soil mineral and organic N contents, but also reduced abundances of the soil communities of Rozellomycota phylum (by 82.76%), ericoid mycorrhiza of Meliniomyces varia (by 81.60%) and Phialocephala fort (by 69.54%). Vaccinium uliginosum overcame L. palustre through higher N utilization (biomass/%N) although the latter had higher abundances of soil Odiodendron maius and P. fort. The microbial community attributes accounted for a large proportion of N availability following the removal of dominance. In conclusion, our study demonstrates that understory agronomic plants in northern boglands should no longer be under continuous exploitation. Strategies should be considered to improve the promotion of N uptake by managing local soil microbial communities

Data_Sheet_1_Application of Sodium Silicate Enhances Cucumber Resistance to Fusarium Wilt and Alters Soil Microbial Communities.doc

<p>Exogenous silicates can enhance plant resistance to pathogens and change soil microbial communities. However, the relationship between changes in soil microbial communities and enhanced plant resistance remains unclear. Here, effects of exogenous sodium silicate on cucumber (Cucumis sativus L.) seedling resistance to Fusarium wilt caused by the soil-borne pathogen Fusarium oxysporum f.sp. cucumerinum Owen (FOC) were investigated by drenching soil with 2 mM sodium silicate. Soil bacterial and fungal community abundances and compositions were estimated by real-time PCR and high-throughput amplicon sequencing; then, feedback effects of changes in soil biota on cucumber seedling resistance to FOC were assessed. Moreover, effects of sodium silicate on the growth of FOC and Streptomyces DHV3-2, an antagonistic bacterium to FOC, were investigated both in vitro and in the soil environment. Results showed that exogenous sodium silicate enhanced cucumber seedling growth and resistance to FOC. In bare soil, sodium silicate increased bacterial and fungal community abundances and diversities. In cucumber-cultivated soil, sodium silicate increased bacterial community abundances, but decreased fungal community abundances and diversities. Sodium silicate also changed soil bacterial and fungal communality compositions, and especially, decreased the relative abundances of microbial taxa containing plant pathogens but increased these with plant-beneficial potentials. Moreover, sodium silicate increased the abundance of Streptomyces DHV3-2 in soil. Soil biota from cucumber-cultivated soil treated with sodium silicate decreased cucumber seedling Fusarium wilt disease index, and enhanced cucumber seedling growth and defense-related enzyme activities in roots. Sodium silicate at pH 9.85 inhibited FOC abundance in vitro, but did not affect FOC abundance in soil. Overall, our results suggested that, in cucumber-cultivated soil, sodium silicate increased cucumber seedling resistance to Fusarium wilt by changing soil microbial communities rather than by directly inhibiting the growth of FOC.</p

Advances in Studies of Biological Nitrogen Saving Technology for Wheat

This paper first described the current status of wheat nitrogen fertilizers utilization rate. Then, from balanced fertilizer application, applying slow/controlled release fertilizer, deep application of nitrogen fertilizers and graded application, controlled application amount, selection of application time according to soil properties, diagnosed application of fertilizer with instrument, addition of synergist, and precise fertilizer application, it summarized biological nitrogen saving methods and introduced prospects of future biological nitrogen saving technology

Selection and Breeding of Drought Resistant, Water-saving and High-yield Wheat Variety Cangmai 028

Cangmai 028 was selected and bred according to the climatic characteristic of the winter wheat in Heilonggang Basin taking 98 (083) as the female parent and the Canghe 030 as the male parent by “two-row parallel alternate selection” method. Cangmai 028 has characteristics of high resistance, water-saving, high and stable yield, and rich genetic background. This study elaborated selection and breeding background and methods, characteristics, quality, and yield of Cangmai 028

Dissection of <i>Paenibacillus polymyxa</i> NSY50-Induced Defense in Cucumber Roots against <i>Fusarium oxysporum</i> f. sp. <i>cucumerinum</i> by Target Metabolite Profiling

To gain insights into the roles of beneficial PGPR in controlling soil-borne disease, we adopted a metabolomics approach to investigate the beneficial impacts of P. polymyxa NSY50 on cucumber seedling roots under the pathogen of Fusarium oxysporum f. sp. cucumerinum (FOC). We found that NSY50 pretreatment (NSY50 + FOC) obviously reduced the production of reactive oxygen species (ROS). Untargeted metabolomic analysis revealed that 106 metabolites responded to NSY50 and/or FOC inoculation. Under FOC stress, the contents of root osmotic adjustment substances, such as proline and betaine were significantly increased, and dehydroascorbic acid and oxidized glutathione (GSH) considerably accumulated. Furthermore, the contents of free amino acids such as tryptophan, phenylalanine, and glutamic acid were also significantly accumulated under FOC stress. Similarly, FOC stress adversely affected glycolysis and the tricarboxylic acid cycles and transferred to the pentose phosphate pathway. Conversely, NSY50 + FOC better promoted the accumulation of α-ketoglutaric acid, ribulose-5-phosphate, and 7-phosphosodiheptanone compared to FOC alone. Furthermore, NSY50 + FOC activated GSH metabolism and increased GSH synthesis and metabolism-related enzyme activity and their encoding gene expressions, which may have improved redox homoeostasis, energy flow, and defense ability. Our results provide a novel perspective to understanding the function of P. polymyxa NSY50, accelerating the application of this beneficial PGPR in sustainable agricultural practices