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Background Botrytis cinerea can cause serious disease on lots of plant hosts during growth and postharvest storage. Biocontrol is known to be eco-friendly methods to control pathogens. Plant endophytic bacteria are generally considered as beneficial organisms, since they can promote plant growth and enhance plant immune system. Thus, screening biological control agents is very important for sustainable plant protection. Results Fifty-six endophytic bacteria were obtained from wild grape. Sixteen isolates and their extracts exhibited significant antifungal activity against B. cinerea . Particularly, strain JRX-YG39 with the strongest inhibition ability had a broad-spectrum antifungal activity. Combining 16S rDNA analysis and the phylogenetic results based on gyr A and gyr B genes, JRX-YG39 was assigned as Bacillus velezensis . JRX-YG39 could produce bioactive VOCs and obviously depressed mycelia growth of B. cinerea . It was confirmed that VOCs released by JRX-YG39 could significantly promote growth and induce defense of Arabidopsis thaliana . Thirty-one bioactive secondary metabolites were further identified from JRX-YG39 culture by gas chromatography–mass spectrometry analysis. Dibutyl phthalate, a potential antifungal substance, was the major compound accounting for 78.65%. Conclusions B. velezensis JRX-YG39 has wide broad-spectrum antagonistic activity and significant plant promotion activity. Hence, B. velezensis JRX-YG39 will provide a valuable constituent of modern agricultural practice as biofertilizers and biocontrol agents.

ObjectiveThe development of myopia is subject to individual genetic predisposition and environmental risk exposures. This study aims to investigate the trajectories and predictors of spherical equivalent (SE) among multiethnic school-aged children in Southwest China.MethodsThe school-based cohort study was conducted from October 2020 to March 2023 in Yunnan province, Southwest China. Ocular examinations and questionnaire surveys were administered at each visit. A total of 679 students with complete records from all three visits were included in the final analyses. Group-based trajectory modelling was used to identify SE trajectories. Associations between the trajectory groups and baseline predictors were assessed using multinomial logistic regression.ResultsWe identified two distinct trajectory groups of SE in grades 2–3: slow progressive (84.4% of students) and rapid progressive (15.6%). Multivariate analysis indicated that children with myopic parents and those who often stayed in the classrooms during recess were more likely to belong to the rapid progressive group. By contrast, three trajectory groups of SE were identified in grade 7: slow progressive (52.3% of students), moderate initial and rapid progressive (33%) and low initial and rapid progressive (14.7%). In multivariate models, being a girl, having myopic parents, using mobile screens for more than 0.5 hours per day and often staying in the classrooms during recess were predictors of the progressive groups. Moreover, there were no significant differences in SE trajectories between Han and ethnic groups.ConclusionThere is heterogeneity in the developmental trajectories of SE, for both primary and secondary school students. Tailored intervention strategies based on the predictors of the SE trajectories should be under special consideration.

ObjectiveTo investigate the relationship between sleep duration and myopia among primary school students in minority regions of Southwest China.MethodsThe school-based, cross-sectional study was conducted from October 2020 to January 2021. All participants underwent a comprehensive ocular examination and completed a questionnaire on demographic characteristics, ophthalmological history and major environmental factors for myopia. Spherical equivalent (SE) and ocular biometric parameters were measured after cycloplegia, with myopia being defined as SE ≤−0.5 D (Diopter). Multivariate regression models were used to examine the association of sleep duration with myopia, SE and axial length (AL).ResultsA total of 857 students from grades 2 to 4 were included in the analysis, of which 63.6% were myopic and 62.0% belonged to ethnic minorities. Boys had a slightly higher prevalence of myopia compared with girls (66.7% vs 60.6%, p=0.06). Myopic students had longer AL, deeper anterior chamber depth and thinner central corneal thickness compared with non-myopic students (all p<0.05). There was no significant association between sleep duration and myopia in both boys and girls (p=0.319 and 0.186, respectively). Moreover, girls with a sleep duration of 8–9 hour/day had higher SE and shorter AL compared with those with less than 8 hour/day of sleep (β=0.41 and −0.32, respectively, all p<0.05).ConclusionThis cross-sectional study did not find a significant association between sleep duration and myopia. However, it suggests that 8–9 hours of sleep per day may have a protective effect on SE progression and AL elongation in girls. Future studies with objectively measured sleep duration are needed to validate the findings.

Grey mold, caused by Botrytis cinerea, is a widespread and harmful disease of tomato. Biocontrol agents derived from endophytic bacteria are known to hold great potential for inhibition of phytopathogen. We conducted this study to explore the tomato endophytic strains with inhibition activity against B. cinerea. Endophytic strain Bacillus velezensis FQ-G3 exhibited excellent inhibition activity against B. cinerea. Inhibitory effects against B. cinerea were investigated both in vitro and in vivo. The in vitro assays displayed that FQ-G3 could significantly inhibit mycelia growth with inhibition rate of 85.93%, and delay conidia germination of B. cinerea. Tomato fruit inoculated with B. velezensis FQ-G3 revealed lower grey mold during treatment. The antifungal activity was attributed to activation of defense-related enzymes, as evidenced by the higher levels of peroxidase, polyphenol oxidase, and phenylalanine ammonia lyase in tomatoes after inoculation. In addition, scanning electron microscope was applied to elucidate the interaction between endophytes and pathogen, and bacterial colonization and antibiosis appeared to be the underlying mechanisms that FQ-G3 could suppress growth of B. cinerea. Collectively, our present results suggested that FQ-G3 may potentially be useful as a biocontrol agent in postharvest tomatoes.

Tomato fusarium wilt, caused by Fusarium oxysporum f. sp. lycopersici, is a widespread disease occurring in majority of tomato cultivation areas worldwide. Homeobox transcription factor-encoding genes play a vital role in fungal vegetative growth and morphology, but their role in fungal pathogenicity is largely unknown. In this study, 25 homeobox genes (FoHOX 1–25) were identified in the F. oxysporum f. sp. lycopersici genome, using bioinformatics methods. Phylogenetic analysis showed that the FoHOX genes were divided into four groups; furthermore, these genes were unevenly distributed on six chromosomes and qRT-PCR analysis revealed that all 25 were differentially expressed in the host during plant-pathogen interaction. During our study, expression levels of the respective genes in tomato seedlings increased from day one to seven, and most genes showed a decreasing expression trend by day ten. In conclusion, these results may provide a useful foundation for functional analyses of homeobox transcription factor genes involved in the pathogenicity, and regulation of plant immunity.

Phytophthora spp. is a primary pathogen in oomycete, causing economically and environmentally devastating epidemics of plants. Laccases have been found in all domains of life but have not been reported in oomycte. In this paper, laccase genes of Phytophthora spp. were identified in three genomes (Phytophthora capsici, Phytophthora sojae and Phytophthora ramorum). 18 laccase genes were identified in total, including four in P. capsici genome, six in P. sojae genome and eight in P. ramorum genome. Most of the predicted gene models shared typical fungal laccase character, possessing three conserved positions with one cysteine and ten histidine residues at these positions. Phylogenetic analysis illustrated that laccases from Phytophthora clustered into four clades, while fungal laccases clustered together. The results provided the theoretical ground for new hypotheses about the roles laccases in oomycetes and may guide the future research of these enzymes.

Laccases are blue copper oxidases (E.C. 1.10.3.2) that catalyze the one-electron oxidation of phenolics, aromatic amines, and other electron-rich substrates with the concomitant reduction of O2 to H2O. A novel laccase gene pclac2 and its corresponding full-length cDNA were cloned and characterized from Phytophthora capsici for the first time. The 1683 bp full-length cDNA of pclac2 encoded a mature laccase protein containing 560 amino acids preceded by a signal peptide of 23 amino acids. The deduced protein sequence of PCLAC2 showed high similarity with other known fungal laccases and contained four copper-binding conserved domains of typical laccase protein. In order to achieve a high level secretion and full activity expression of PCLAC2, expression vector pPIC9K with the Pichia pastoris expression system was used. The recombinant PCLAC2 protein was purified and showed on SDS-PAGE as a single band with an apparent molecular weight ca. 68 kDa. The high activity of purified PCLAC2, 84 U/mL, at the seventh day induced with methanol, was observed with 2,2'-azino-di-(3-ethylbenzothialozin-6-sulfonic acid) (ABTS) as substrate. The optimum pH and temperature for ABTS were 4.0 and 30 °C, respectively. The reported data add a new piece to the knowledge about P. Capsici laccase multigene family and shed light on potential function about biotechnological and industrial applications of the individual laccase isoforms in oomycetes.

A new type of sulfobetaine with double alkyl polyoxyethylene ( n ) ether chains, dicoconut oil alcohol polyoxethylene ( n ) ether methylhydroxylpropyl sulfobetaine (diC 12–14 E n HSB) was synthesized using a commercial nonionic surfactant, coconut oil alcohol polyoxethylene ( n ) ether, as raw material and its properties as a surfactant for enhanced oil recovery (EOR) in the absence of alkali was studied. The purified product is a mixture of homologues with mainly C 12 /C 12 , C 12 /C 14 and C 14 /C 14 alkyl chains and widely distributed EO chains ( n  = 2.2 on average) with an average molar mass of 742.6 g/mol. The diC 12–14 E 2.2 HSB has an improved aqueous solubility at 25 °C compared with didodecylmethylhydroxylpropyl sulfobetaine (diC 12 HSB), a homologue without an EO chain, and is highly surface active as reflected by its low CMC (4.6 × 10 −6 mol/L), high saturated adsorption (6.8 × 10 −10  mol/cm 2 ) and small cross sectional area (0.24 nm 2 /molec.) at the air/water interface. With a hydrophile–lipophile balance well matched with Daqing crude oil/connate water system, the sulfobetaine can reduce Daqing crude oil/connate water interfacial tension to ultra-low values at 45 °C in the absence of alkali, and displays a low saturated adsorption at the sandstone/water interface (0.0024 mmol/g), reduced by 69 and 92 % respectively in comparison with that of the corresponding carboxyl betaine, diC 12–14 E 2.2 B and its homologue without an EO chain, didodecylmethylcarboxyl betaine (diC 12 B). With these excellent properties diC 12–14 E 2.2 HSB gives a high tertiary recovery, 18.4 % original oil in place, when mixed with other hydrophobic and hydrophilic sulfobetaines in surfactant-polymer (SP) flooding free of alkali. The insertion of EO chains in combination with the replacement of carboxyl betaine by sulfobetaine is therefore very efficient for improving the properties of the double chain hydrophobic carboxyl betaines as surfactants for SP flooding free of alkali.

Velvet genes play critical roles in the regulation of diverse cellular processes. In current study, we identified the gene FocVel1, a homolog of Fusarium graminearum VelA, in the plant pathogenic fungus F. oxysporum f. sp. cucumerinum. This pathogen causes the destructive disease called cucumber Fusarium wilt (CFW), which severely affects the production and marketing of this vegetable worldwide. Transcript analyses revealed high expression of FocVel1 during conidiophore development. Disruption of the FocVel1 gene led to several phenotypic defects, including reduction in aerial hyphal formation and conidial production. The deletion mutant ΔFocVel1 showed increased resistance to both osmotic stress and cell wall-damaging agents, but increased sensitivity to iprodione and prochloraz fungicides, which may be related to changes in cell wall components. In the process of biofilm formation in vitro, the mutant strain ΔFocVel1 displayed not only a reduction in spore aggregation but also a delay in conidial germination on the polystyrene surface, which may result in defects in biofilm formation. Moreover, pathogenicity assays showed that the mutant ΔFocVel1 exhibited impaired virulence in cucumber seedlings. And the genetic complementation of the mutant with the wild-type FocVel1 gene restored all the defects of the ΔFocVel1. Taken together, the results of this study indicated that FocVel1 played a critical role in the regulation of various cellular processes and pathogenicity in F. oxysporum f. sp. cucumerinum.