Impact of PaGLK transgenic poplar on microbial community and soil enzyme activity in rhizosphere soil

Dynamic response of allelopathic potency of Taxus cuspidata Sieb. et Zucc. mediated by allelochemicals in Ficus carica Linn. root exudates

In a mixed forest, certain plants can release allelochemicals that exert allelopathic effects on neighboring plants, thereby facilitating interspecific coexistence of two species. Previous studies have demonstrated that allelochemicals released from Ficus carica Linn. roots in mixed forest of F. carica and Taxus cuspidata Sieb. et Zucc. has phase characteristics over time, which can improve the soil physicochemical properties, enzyme activity and microbial diversity, thus promoting the growth of T. cuspidata. Based on the irrigation of exogenous allelochemicals, changes in soil fertility (soil physical and chemical properties, soil enzyme activity and soil microelement content) were observed in response to variations in allelochemicals during five phases of irrigation: initial disturbance phase (0-2 d), physiological compensation phase (2-8 d), screening phase (8-16 d), restore phase (16-32 d) and maturity phase (32-64 d), which was consistent with the response of soil microorganisms. The allelopathic response of growth physiological indexes of T. cuspidata, however, exhibited a slight lag behind the soil fertility, with distinct phase characteristics becoming evident on the 4th day following irrigation of allelochemicals. The findings demonstrated that the allelochemicals released by the root of F. carica induced a synergistic effect on soil fertility and microorganisms, thereby facilitating the growth of T. cuspidata. This study provides a comprehensive elucidation of the phased dynamic response-based allelopathic mechanism employed by F. carica to enhance the growth of T. cuspidata, thus establishing a theoretical basis for optimizing forest cultivation through allelopathic pathways.

Quality variation and salt-alkali-tolerance mechanism of Cynomorium songaricum: Interacting from microbiome-transcriptome-metabolome

Addressing soil salinization and implementing sustainable practices for cultivating cash crops on saline-alkali land is a prominent global challenge. Cynomorium songaricum is an important salt-alkali tolerant medicinal plant capable of adapting to saline-alkali environments. In this study, two typical ecotypes of C. songaricum from the desert-steppe (DS) and saline-alkali land (SAL) habitats were selected. Through the integration of multi-omics with machine learning, the rhizosphere microbial communities, genetic maps, and metabolic profiles of two ecotypes were created and the crucial factors for the adaptation of C. songaricum to saline-alkali stress were identified, including 7 keystone OTUs (i.e. Novosphingobium sp., Sinorhizobium meliloti, and Glycomyces sp.), 5 core genes (cell wall-related genes), and 10 most important metabolites (i.e. cucurbitacin D and 3-Hydroxybutyrate) were identified. Our results indicated that under saline-alkali environments, the microbial competition might become more intense, and the microbial community network had the simple but stable structure, accompanied by the changes in the gene expression related to cell wall for adaptation. However, this regulation led to the reduction in active ingredients, such as the accumulation of flavonoids and organic acid, and enhanced the synthesis of bitter substances (cucurbitacin D), resulting in the decrease in the quality of C. songaricum. Therefore, compared to the SAL ecotype, the DS was more suitable for the subsequent development of medicinal and edible products of C. songaricum. Furthermore, to explore the reasons for this quality variation, we constructed a comprehensive microbial-genetic-metabolic regulatory network, revealing that the metabolism of C. songaricum was primarily influenced by genetic factors. These findings not only offer new insights for future research into plant salt-alkali tolerance strategies but also provide a crucial understanding for cultivating high-quality medicinal plants.

Editing Metabolism, Sex, and Microbiome: How Can We Help Poplar Resist Pathogens?

Poplar (Populus) is a genus of woody plants of great economic value. Due to the growing economic importance of poplar, there is a need to ensure its stable growth by increasing its resistance to pathogens. Genetic engineering can create organisms with improved traits faster than traditional methods, and with the development of CRISPR/Cas-based genome editing systems, scientists have a new highly effective tool for creating valuable genotypes. In this review, we summarize the latest research data on poplar diseases, the biology of their pathogens and how these plants resist pathogens. In the final section, we propose to plant male or mixed poplar populations; consider the genes of the MLO group, transcription factors of the WRKY and MYB families and defensive proteins BbChit1, LJAMP2, MsrA2 and PtDef as the most promising targets for genetic engineering; and also pay attention to the possibility of microbiome engineering.