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Forest biodiversity is an important component of biological diversity that should not be disregarded. The question of how to evaluate it has sparked scholarly inquiry and discussion. The purpose of this paper is to describe the principles of general linear regression, the selection of model variables in OLS autoregressive modelling, model coefficient testing, analysis of variance of autoregressive models, and model evaluation indicators in order to clarify the suitability of GWR models for solving biomass-related data problems. The GWR 4.0 program was used to create a spatially weighted autoregressive model. Model testing and an accuracy analysis were performed on the model. Following a comparison and study with the general linear regression model, it was discovered that the geographically weighted autoregressive model is better suited to defining spatially correlated data than the general linear regression model.

Traditional disposal of animal manures and lignocellulosic biomass is restricted by its inefficiency and sluggishness. To advance the carbon management and greenhouse gas mitigation, this review scrutinizes the effect of pyrolysis in promoting the sustainable biomass and manure disposal as well as stimulating the biochar industry development. This review has examined the advancement of pyrolysis of animal manure (AM) and lignocellulosic biomass (LB) in terms of efficiency, cost-effectiveness, and operability. In particular, the applicability of pyrolysis biochar in enhancing the crops yields via soil remediation is highlighted. Through pyrolysis, the heavy metals of animal manures are fixated in the biochar, thereby both soil contamination via leaching and heavy metal uptake by crops are minimized. Pyrolysis biochar is potentially use in soil remediation for agronomic and environmental co-benefits. Fast pyrolysis assures high bio-oil yield and revenue with better return on investment whereas slow pyrolysis has low revenue despite its minimum investment cost because of relatively low selling price of biochar. For future commercialization, both continuous reactors and catalysis can be integrated to pyrolysis to ameliorate the efficiency and economic value of pyrolysis biochar.

To clarify the histopathological characteristics of Camellia oleifera that were infected by Colletotrichum fructicola, this study utilized frozen tissue sections, whole-stain clearing and transmission electron microscopy to observe the time of transformation from biotrophic to necrotrophic when Co. fructicola infects leaves, as well as the colonization and expansion of the pathogenic fungus at different stages on the leaves. The Co. fructicola conidia produced germ tubes 2 h post-inoculation, and appressoria began to form 4 h after inoculation. There were two ways that pathogens can use to invade the leaves of Ca. oleifera. One was to directly penetrate the host cuticle, while the other involved invasion from the stomata of the host using germ tubes or hyphae. A few infection vesicles could then be observed in the leaf tissue, and the infection vesicles produce thicker septal primary hyphae after 24 h of infection. When the infection reached the 40 h point, the fungus started to produce secondary hyphae with smaller diameter than that of the primary hyphae and gradually expanded into the adjacent cells. Transmission electron microscopy revealed that when the secondary hyphae entered the mesophyll cells, the contents in the cells were digested and a cavity gradually formed, indicating that the cells had been killed. Thus, the appearance of the secondary hyphae marked the point at which Co. fructicola entered into a destructive necrotrophic stage.

Anthracnose, caused by the fungus Collectotrichum fructicola (C. fructicola), is a major disease affecting the quality and yield of Camellia oleifera (C. oleifera); it reduces C. oleifera yield by 40%–80%. Bacillus subtilis (B. subtilis) YL13 is an antagonistic endophytic bacteria strain isolated from healthy C. oleifera leaves. This study was aimed at investigating the potential of YL13 for the biocontrol of C. oleifera anthracnose and the possible mechanisms involved. In in vitro assays, YL13 demonstrated remarkable antagonistic activity of C. fructicola. Its cell-free filtrates displayed antagonistic activity, which suggested that the metabolites of YL13 might play important roles. In vivo tests showed that the disease index of YL13-treated plants was obviously reduced under greenhouse conditions. YL13 secretes a variety of bioactive metabolites, including protease, cellulase, and siderophore, which might participate in the resistance to C. fructicola. In addition, C. oleifera treated with the fermentation broth of YL13 demonstrated different defense responses, e.g., accumulation of hydrogen peroxide (H2O2) and activation of the defense-related enzyme peroxidase (POD), which might contribute directly or indirectly to overcome external stresses. The significant biocontrol effect and host defense-induction activity of YL13 suggested that this B. subtilis strain as well as its metabolites have the potential to be exploited as microbial control agents for the efficient management of C. oleifera anthracnose.

Dalbergia odorifera (D. odorifera), commonly named the fragrant rosewood, is one of the second-level protected wild plants in China, and one of 34 species of rosewood in five genera and eight categories in the National Standard of China. As a kind of traditional Chinese medicine (TCM), it plays an important role in the pharmaceutical industry, including the treatment of cardiovascular diseases, rheumatic pain, etc. With the continuous expansion of the planting area of D. odorifera, the diseases and pests of D. odorifera become more and more serious, among which leaf-eating pests are the most serious. In this study, ultraviolet rays and microwaves were used to mutagenize Beauveria bassiana (B. bassiana) strain HNCMBJ-P-01, and excellent mutant strains with high spore yield and high virulence were screened out, and then they were prepared into a wettable powder for forest control experiments to study their biocontrol effects. The virulence screening test showed that the virulence of strain HBWB-44 was the strongest, and the 10 day corrected mortality rate was 80.00%, and the lethal time was 5.622 days. The results of biological control test showed that the control effect of B. bassiana wettable powder 100 times solution reached 60.89%, second only to the botanical fungicide matrine. Generically, The B. bassiana that we screened and mutated showed a good killing effect on Plecoptera bilinealis (P. bilinealis), and the wettable powder produced by it showed a good control effect on the leaf-eating pests of D. odorifera. The application of fungal insecticides in plantations has a good prospect for controlling the occurrence of leaf-eating pests of D. odorifera.

Background Tea-oil tree (Camellia oleifera) is a unique edible-oil tree in China, and anthracnose occurs in wherever it is cultivated, causing great economic losses each year. We have previously identified the Ascomycete fungus Colletotrichum fructicola as the major pathogen of anthracnose in Ca.oleifera. The purpose of this study was to characterize the biological function of Snf1 protein, a key component of the AMPK (AMP-activated protein kinase) pathway, for the molecular pathogenic-mechanisms of C. fructicola. Results We characterized CfSnf1 as the homolog of Saccharomyces cerevisiae Snf1. Targeted CfSNF1 gene deletion revealed that CfSnf1 is involved in the utilization of specific carbon sources, conidiation, and stress responses. We further found that the ΔCfSnf1 mutant was not pathogenic to Ca.oleifera, resulting from its defect in appressorium formation. In addition, we provided evidence showing crosstalk between the AMPK and the cAMP/PKA pathways for the first time in filamentous fungi. Conclusion This study indicate that CfSnf1 is a critical factor in the development and pathogenicity of C. fructicola and, therefore, a potential fungicide target for anthracnose control.

Camellia yuhsienensis Hu, a species of tea oil tree with resistance to anthracnose, is widely used to breed disease-resistant Camellia varieties. In 2019, anthracnose symptoms were observed on Ca. yuhsienensis for the first time. However, the species and biological characteristics of Colletotrichum spp. isolated from Ca. yuhsienensis (YX-Colletotrichum spp.) have not been elucidated. In this study, five isolates (YX2-5-2, 2YX-3-1, 2YX-5-1, 2YX-8-1-1 and 2YX-8-1-2), which were consistent with the morphological characteristics of Colletotrichum spp., were obtained from Ca. yuhsienensis. A phylogenetic analysis demonstrated that YX2-5-2, 2YX-3-1 and 2YX-8-1-2 belonged to first clade along with Colletotrichum fructicola. 2YX-8-1-1 belonged to the second clade along with Colletotrichum siamense. 2YX-5-1 belonged to the third clade with Colletotrichum camelliae. Pathogenicity tests revealed that the pathogenicity of YX-Colletotrichum spp. was stronger than that of Colletotrichum spp. isolated from Camellia oleifera (GD-Colletotrichum spp.). Biological characteristics illustrated that the mycelial growth of YX-Co. camelliae (2YX-5-1) was slower than that of GD-Co. camelliae when the temperature exceeded 20 °C. In addition, in the presence of ions, the mycelial growth of YX-Co. fructicola (YX2-5-2) and YX-Co. siamense (2YX-8-1-1) was also slower than that of GD-Co. fructicola and GD-Co. siamense. Furthermore, the ability of YX-Colletotrichum spp. to utilize lactose and mannitol was weaker than that of GD-Colletotrichum spp., while the ability to utilize NH4+ was generally stronger than that of GD-Colletotrichum spp. This is the first report of anthracnose of Ca. yuhsienensis induced by Co. fructicola, Co. siamense and Co. camelliae in China. These results will provide theoretical guidance for the study of the pathogenesis and control of anthracnose on Ca. yuhsienensis.

Anthracnose, caused by Colletotrichum spp., is a significant disease affecting oil tea (Camellia oleifera Abel.). Extensive molecular studies have demonstrated that Colletotrichum fructicola is the dominant pathogen of oil tea anthracnose in China. This study aims to investigate differences in molecular processes and regulatory genes at a late stage of infection of C. fructicola, to aid in understanding differences in pathogenic mechanisms of C. fructicola of different geographic populations. We compared the pathogenicity of C. fructicola from different populations (Wuzhishan, Hainan province, and Shaoyang, Hunan province) and gene expression of representative strains of the two populations before and after inoculation in oil tea using RNA sequencing. The results revealed that C. fructicola from Wuzhishan has a more vital ability to impact oil tea leaf tissue. Following infection with oil tea leaves, up-regulated genes in the strains from two geographic populations were associated with galactosidase activity, glutamine family amino acid metabolism, arginine, and proline metabolism. Additionally, up-regulated gene lists associated with infection by Wuzhishan strains were significantly enriched in purine metabolism pathways, while Shaoyang strains were not. These results indicate that more transcriptional and translational activity and the greater regulation of the purine metabolism pathway in the C. fructicola of the Wuzhishan strain might contribute to its stronger pathogenicity.

Soil ecosystem imparts a fundamental role in the growth and survival of the living creatures. The interaction between living and non-living constituents of the environment is important for the regulation of life in the ecosystem. Biochar is a carbon rich product present in the soil that is responsible for various applications in diversified fields. In this review, we focused on the collaboration between the soil, biochar and microbial community present in the soil and consequences of it in the ecosystem. Herein, it primarily discusses on the different approaches of the production and characterization of biochar. Furthermore, this review also discusses about the optimistic interaction of biochar with soil microbes and their role in plant growth. Eventually, it reveals the various physio-chemical properties of biochar, including its specific surface area, porous nature, ion exchange capacity, and pH, which aid in the modification of the soil environment. Furthermore, it elaborately discloses the impact of the biochar addition in the soil focusing mainly on its interaction with microbial communities such as bacteria and fungi. The physicochemical properties of biochar significantly interact with microbes and improve the beneficial microbes growth and increase soil nutrients, which resulting reasonable plant growth. The main focus remains on the role of biochar-soil microbiota in remediation of pollutants, soil amendment and inhibition of pathogenicity among plants by promoting resistance potential. It highlights the fact that adding biochar to soil modulates the soil microbial community by increasing soil fertility, paving the way for its use in farming, and pollutant removal.

Colletotrichum fructicola is a fungal pathogen that causes Camellia oleifera anthracnose. Mitogen-activated protein kinase cascade signaling regulates plants defenses and is modulated by Ste50, a scaffold protein that mediates the interaction of Ste11 and Ste7. In this study, the Saccharomyces cerevisiae STE50 homolog CfSTE50 in C. fructicola was identified and disrupted. CfSTE50 encodes a 482 amino acid protein. The mutants showed significant differences in conidial yields and appressorium failed to form. Vegetative growth also decreased compared to wild-type strains. Inoculation with conidial suspensions showed that the virulence of the mutant on wounded leaves was significantly impaired. Further analysis showed that the targeted deletion of CfSTE50 resulted in enhanced sensitivity to external peroxide stress, but reduced sensitivity to cell wall stress. These results provide evidence that CfSte50 regulates the growth and development of C. fructicola and regulates asexual reproduction, appressorium formation, pathogenicity and the response to external stresses.

Anthracnose, caused by Colletotrichum. Spp., is an important disease affecting oil tea (Camellia oleifera). Extensive molecular studies have demonstrated that Colletotrichum fructicola is the dominant pathogen of oil tea anthracnose in China. The study aims to investigate differences in molecular processes and regulatory genes at different stages of infection of C. fructicola, to aide in understanding differences in pathogenic mechanisms of C. fructicola of different geographic populations. Materials and Methods: We compared the pathogenicity of C. fructicola from different populations (Wuzhishan, Hainan province and Shaoyang, Hunan province), and gene expression of representative strains of the two populations before and after inoculation in oil tea using RNA sequencing. In results we found that C. fructicola from Wuzhishan has a stronger ability to infect and impact oil tea leaf tissue. Up-regulated genes in oil tea following infection with the two geographic populations were associated with a number of ribosome-related GO terms and ribosome metabolic related KEGG pathways, and were significantly enriched in galactosidase activity, glutamine family amino acid metabolism, arginine and proline metabolism. In addition, up-regulated gene lists associated with infection in the Wuzhishan strains were significantly enriched purine metabolism pathways as well, while Shaoyang strains were not significantly enriched in these processes. Differences in gene expression were indicative of greater active transcription and translation in the Wuzhishan population while more active glycoprotein metabolism was observed following inoculation with strains from Shaoyang. These results indicate that C. fructicola obtained sugars and amino acids from oil tea tissue to resist host immune pressure. Moreover, more active in transcriptional and translational activity and the greater regulation of purine metabolism pathway in the Wuzhishan strain might contribute to its stronger pathogenicity.

The filamentous fungus Colletotrichum fructicola is found in all five continents and is capable of causing severe diseases in a number of economically important plants such as avocado, fig, cocoa, pear, and tea-oil trees. However, almost nothing is known about its patterns of genetic variation and epidemiology on any of its host plant species. Here we analyzed 167 isolates of C. fructicola obtained from the leaves of tea-oil tree Camellia oleifera at 15 plantations in seven Chinese provinces. Multilocus sequence typing was conducted for all isolates based on DNA sequences at fragments of four genes: the internal transcribed spacers of the nuclear ribosomal RNA gene cluster (539 bp), calmodulin (633 bp), glutamine synthetase (711 bp), and glyceraldehyde-3-phosphate dehydrogenase (190 bp), yielding 3.52%, 0.63%, 8.44%, and 7.89% of single nucleotide polymorphic sites and resulting in 15, 5, 12 and 11 alleles respectively at the four gene fragments in the total sample. The combined allelic information from all four loci identified 53 multilocus genotypes with the most frequent represented by 21 isolates distributed in eight tea-oil plantations in three provinces, consistent with long-distance clonal dispersal. However, despite evidence for clonal dispersal, statistically significant genetic differentiation among geographic populations was detected. In addition, while no evidence of recombination was found within any of the four gene fragments, signatures of recombination were found among the four gene fragments in most geographic populations, consistent with sexual mating of this species in nature. Our study provides the first insights into the population genetics and epidemiology of the important plant fungal pathogen C. fructicola.

Bio-fertilizers are of great importance in forestry because they can positively affect plant growth and the environment. In this study, the seedlings of slash pine (Pinus elliottii) were planted in pots. One month later they were inoculated with 7 groups of ectomycorrhizal fungi including Lactarius sp., Scleroderma polyrhizum Pers., Lactarius hatsudake Tanaka,Lycoperdon sp., Lycoperdon sp./ Lactarius sp., Lycoperdon sp. / Lactarius hatsudakeTanaka and Scleroderma polyrhizum Pers./ Lactarius sp.. Plant growth variables were determined after three months. The results showed that: (1) all inocula signii¬cantly increased the ground diameter and plant height and strengthened the overall absorption of nitrogen, phosphorus and potassium; (2) the best inocula mixture was Lycoperdon sp. /Lactarius hatsudake Tanaka, likely due to synergistic interactions between the two partners and (3) mixed ectomycorrhizal fungi were not necessarily better than single fungus. Key words: Slash pine (Pinus elliottii) growth, ectomycorrhizal inocula, bio-fertilizers, interaction, mixed ectomycorrhizal fungi.

Plackett–Burman design and Box–Behnken response surface methodology (RSM) was employed to optimize the medium components for the chitin deacetylase (CDA) activity from Bacillus amyloliquefaciens Z7. Plackett–Burman design was applied to determine the specific medium components affecting CDA activity and found that starch, chitin and MgSO4 were critical in augmenting CDA activity. These significant parameters were further optimized using Box–Behnken RSM and the optimum concentrations of starch, chitin and MgSO4 were found to be 24.4, 8.8 and 0.19 g/L, respectively. The optimum medium composition was chitin 8.8 g/L, starch 24.4 g/L, yeast extract 10g/L, MgSO4 0.19 g/L, K2HPO4 0.3 g/L and NaCl 5 g/L. Under these optimal conditions, the CDA activity of Bacillus amyloliquefaciens Z7 increased distinctly from 18.75 to 27.48 U/mL (46.6% increase in total yield).

Filamentous fungal strains were isolated from the leaves and fruits of Camellia oleifera with the anthracnose disease. The pathogenecity was tested following Koch's postulates. Our analyses identified that all 18 isolated strains were pathogenic to Camellia oleifera. The molecular analysis of the internal transcribed spacer regions of the most virulent isolate confirmed that it belonged to Colletotrichum gloeosporioides. 165 strains were isolated from the leaves of Camellia oleifera, which were collected from Henyang, Liuyang, Changde etc in Hunan province. There were three entophytic bacteria strains Y13，S2，H18 against Colletotrichum gloeosporioides. And more, Strain Y13 was antagonistic against different Pathogenic fungi, Fusarium oxysporium、Thanatephorus cucumeris、Alternaria solan、PestalotiopsisStey, and its inhibition rates were 84.3%、81.8%、80.0% and 80.1%. The result showed that Strain Y13 had a wider antibacterial spectrum and the strong antagonistic activity. Our analyses and Strain Y13 study should help future identification, prevention and treatment of the Camellia oleifera anthracnose disease.

Chitosan, derived from chitin by partial N-deacetylation, has been found to be non-toxic, biocompatible and biodegrable. So chitosan has high economic value and environmental impact. The study mainly compared the antifungal activities with two types of chitosan (W-CS, I-CS). The results indicated that W-CS and I-CS had high antifungal activities against the pathogens caused camellia anthracnose. As W-CS and I-CS concentrations increased from 1 mg-mL -1 to 10 mg-mL -1 antifungal went up significantly. The optimal pH range of chitosan for the highest antifungal activity was 5.3 to 6.0 with tartaric and acetic acid as solvent. The recommend treatment of 2.5 mg-mL -1 W-CS+1%HAC had the inhibition rate of 72.6%, which had almost 500 times effectives than that of thiophanate. Our results should help to develop for a new type of environmental friendly pesticide.

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