An endophytic bacterium Bacillus velezensis BY6 was isolated from the wood stems of healthy Populus davidiana × P. alba var. pyramidalis (PdPap). The BY6 strain can inhibit pathogenic fungus Alternaria alternate in PdPap and promote growth of PdPap seedlings. In the present study, we used the Pacific Biosciences long‐read sequencing platform, a single‐molecule real‐time (SMRT) technology for strain BY6, to perform complete genome sequencing. The genome size was 3,898,273 bp, the number of genes was 4,045, and the average GC content was 47.33%. A complete genome of strain BY6 contained 110 secondary metabolite gene clusters. Nine of the secondary metabolite gene clusters exhibited antifungal activity and promoted growth functions primarily involved in the synthesis of surfactin, bacteriocins, accumulated iron ions, and related antibiotics. Gene clusters provide genetic resources for biotechnology and genetic engineering, and enhance understanding of the relationship between microorganisms and plants.
(1) Objective: The opacity of soils complicates studies of root infection. An example of this is the infection of Armillaria solidipes on poplar (Populus davidiana × Populus alba var. pyramidalis Louche) roots systems, which risks damaging trees. (2) Methods: Only one of the four tested substrates for tree species was shown to be suitable to perform X-ray computed tomography (CT). Three-dimensional (3D) imaging was used to reconstruct the root system of poplar seedlings and the changes caused by the infection. (3) Results: We developed a protocol to efficiently grow poplar on a synthetic matrix, vermiculite, that allows for monitoring the root system by X-ray CT. Poplar 3D reconstruction of the root system was automated using the software Win-RHIZO, and various infection parameters were identified. (4) Conclusions: Our procedure allows for monitoring the infection of root systems and provides new opportunities to characterize the complex Armillaria solidipes poplar interaction using X-ray CT.
Coarse roots and the root plate play an important role in tree resistance to uprooting. In this study, a qualitative mechanistic model was developed to analyze coniferous tree resistance to uprooting in relation to tree morphological characteristics. The sizes of the crown, stem, and root plate of twenty sample spruces and twenty sample Korean pines were individually measured for this purpose. Using Ground Penetrating Radar (GPR), the coarse root distribution and root plate size were detected. In the qualitative mechanistic model, a larger crown area increased the overturning moment, while higher DBH and root plate mass increased the resistance moment. The resistance coefficient (Rm) was calculated by comparing resistive and overturning moments, classifying samples into three uprooting hazard levels. Trees with smaller crown areas, larger stems, and root plates tend to have higher resistance to uprooting, as indicated by higher Rm values. This qualitative mechanistic model provides a useful tool for assessing coniferous standing tree uprooting resistance.
In this paper, the macro-environment and microenvironment factors that have significant impacts on the development of a biopower plant located in Heilongjiang Province, China were analyzed using the PEST and SWOT analyses. The analytical results showed that the biopower plant should actively optimize its fuel supply network, efficiently utilize the current national policies and local abundant resources, seize the development opportunities, and avoid the weakness in order to keep the leading role and realize sustainable development in bio-industry.