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Xanthomonas and Stenotrophomonas are closely related genera in the family Lysobacteraceae. In our previous study of aroid-associated bacterial strains, most strains isolated from anthurium and other aroids were reclassified as X. phaseoli and other Xanthomonas species. However, two strains isolated from Spathiphyllum and Colocasia were phylogenetically distant from other strains in the Xanthomonas clade and two strains isolated from Anthurium clustered within the Stenotrophomonas clade. Phylogenetic trees based on 16S rRNA and nine housekeeping genes placed the former strains with the type strain of X. sacchari from sugarcane and the latter strains with the type strain of S. bentonitica from bentonite. In pairwise comparisons with type strains, the overall genomic relatedness indices required delineation of new species; digital DNA–DNA hybridization and average nucleotide identity values were lower than 70 and 95%, respectively. Hence, three new species are proposed: S. aracearum sp. nov. and S. oahuensis sp. nov. for two strains from anthurium and X. hawaiiensis sp. nov. for the strains from spathiphyllum and colocasia, respectively. The genome size of X. hawaiiensis sp. nov. is ~4.88 Mbp and higher than S. aracearum sp. nov. (4.33 Mbp) and S. oahuensis sp. nov. (4.68 Mbp). Gene content analysis revealed 425 and 576 core genes present in 40 xanthomonads and 25 stenotrophomonads, respectively. The average number of unique genes in Stenotrophomonas spp. was higher than in Xanthomonas spp., implying higher genetic diversity in Stenotrophomonas.

Abstract Dickeya fangzhongdai, a bacterial pathogen of taro (Colocasia esculenta), onion (Allium sp.), and several species in the orchid family (Orchidaceae) causes soft rot and bleeding canker diseases. No field-deployable diagnostic tool is available for specific detection of this pathogen in different plant tissues. Therefore, we developed a field-deployable loop-mediated isothermal amplification (LAMP) assay using a unique genomic region, present exclusively in D. fangzhongdai. Multiple genomes of D. fangzhongdai, and other species of Dickeya, Pectobacterium and unrelated genera were used for comparative genomic analyses to identify an exclusive and conserved target sequence from the major facilitator superfamily (MFS) transporter gene region. This gene region had broad detection capability for D. fangzhongdai and thus was used to design primers for endpoint PCR and LAMP assays. In-silico validation showed high specificity with D. fangzhongdai genome sequences available in the NCBI GenBank genome database as well as the in-house sequenced genome. The specificity of the LAMP assay was determined with 96 strains that included all Dickeya species and Pectobacterium species as well as other closely related genera and 5 hosts; no false positives or false negatives were detected. The detection limit of the assay was determined by performing four sensitivity assays with tenfold serially diluted purified genomic DNA of D. fangzhongdai with and without the presence of crude host extract (taro, orchid, and onion). The detection limit for all sensitivity assays was 100 fg (18–20 genome copies) with no negative interference by host crude extracts. The assays were performed by five independent operators (blind test) and on three instruments (Rotor-Gene, thermocycler and dry bath); the assay results were concordant. The assay consistently detected the target pathogen from artificially inoculated and naturally infected host samples. The developed assay is highly specific for D. fangzhongdai and has applications in routine diagnostics, phytosanitary and seed certification programs, and epidemiological studies.

Colletotrichum scovillei causes anthracnose of chili pepper in many countries. Three strains of this pathogen, Coll-524, Coll-153, and Coll-365, show varied virulence on chili pepper. Among the three strains, Coll-365 showed significant defects in growth and virulence. To decipher the genetic variations among these strains and identify genes contributing to growth and virulence, comparative genomic analysis and gene transformation to show gene function were applied in this study. Compared to Coll-524, Coll-153, and Coll-365 had numerous gene losses including 32 candidate effector genes that are mainly exist in acutatum species complex. A cluster of 14 genes in a 34-kb genomic fragment was lost in Coll-365. Through gene transformation, three genes in the 34-kb fragment were identified to have functions in growth and/or virulence of C. scovillei. CsPLAA encoding a phospholipase A2-activating protein enhanced the growth of Coll-365. A combination of CsPLAA with one transcription factor CsBZTF and one C6 zinc finger domain-containing protein CsCZCP was found to enhance the pathogenicity of Coll-365. Introduction of CsGIP, which encodes a hypothetical protein, into Coll-365 caused a reduction in the germination rate of Coll-365. In conclusion, the highest virulent strain Coll-524 had more genes and encoded more pathogenicity related proteins and transposable elements than the other two strains, which may contribute to the high virulence of Coll-524. In addition, the absence of the 34-kb fragment plays a critical role in the defects of growth and virulence of strain Coll-365.

Transportation safety has been widely discussed for avoiding forward collisions. The broad concept of remote sensing can be applied to detect the front of vehicles without contact. The traditional Haar features use adjacent rectangular areas for many ordinary vehicle studies to detect the front vehicle images in practice. This paper focused on large vehicles using a front-installed digital video recorder (DVR) with a near-infrared (NIR) camera. The views of large and ordinary vehicles are different; thus, this study used a deep learning method to process progressive improvement in moving vehicle detection. This study proposed a You Only Look Once version 4 (YOLOv4) supplemented with the fence method, called YOLOv4(III), to enhance vehicle detection. This method had high detection accuracy and low false omission rates using the general DVR equipment, and it provided comparison results. There was no need to have a high specification front camera, and the proposed YOLOv4(III) was found to have competitive performance. YOLOv4(III) reduced false detection rates and had a more stable frame per second (FPS) performance than with Haar features. This improved detection method can give an alert for large vehicle drivers to avoid serious collisions, leading to a reduction in the waste of social resources.

The family Araceae, comprising ornamentals including Anthurium, Dieffenbachia, Philodendron, Colocasia, and Zontedeschia, is susceptible to Xanthomonas pathogens. Previous analyses have established hetero-geneity in aroid strains, yet unresolved taxonomic positions and dynamics between Xcinthomonas and frequently associated Stenotrophomonas in aroids necessitate in-depth genetic investigation to resolve these complex relationships. This study utilized multilocus sequence analysis of housekeeping genes al/D, dnaA. dnaK, gltA, and gyrB to investigate 59 aroid strains, selected based on hosts, tinie. and geographical wholeorigins. After adding sequences from additional strains from NCBI Gen Bank, analysis of 161 concatenated sequences indicated that all aroid strains fell within Xanthomoncts and Stenotrophomonas. Thirty-six strains isolated from Anthurium grouped under X. phaseoli, with outliers including one strain each in X. arboricola and X. sacchan and two in Stenotrophomonas. Six strains from Caladium, Dieffenbachia, and Philodendrcni formed host - specific subgroups within X. curesic citoria. One strain from Dieffenbachia aligned with X. campestris, whereas strains from Colocasia. Aglaonema. and Spathiphytium clustered with X. sacchari. Apart from the zantedeschia strain described as X. arboricola pv. zantedeschine. two colocasia, one epipreninum, and one anthurium strainjoinedthe X. arboricola group. Overall, this study revealed significant heterogeneity among aroid strains, with anthurium strains clustering closely despite distant geographical origins. The analysis underscores the complexity of host-pathogen specificity within Xanthomonas and emphasizes the need for further taxonomic clarification through wholeorigins. genome analysis of representative strains. The findings of this research will facilitate strain selection for inclusivity and exclusivity panels in developing diagnostic assays for X. phaseoli and xanthomonads affecting aroids. [ABSTRACT FROM AUTHOR]