Pseudomonas uvaldensis sp. nov., a bacterial pathogen causing onion bulb rot

Abstract

A Gram-stain-negative, aerobic and non-spore-forming bacterial strain, designated 20TX0172T, was isolated from a rotting onion bulb in Texas, USA. The results of phylogenetic analysis based on the 16S rRNA sequence indicated that the novel strain represented a member of the genus Pseudomonas and had the greatest sequence similarities with Pseudomonas kilonensis 520-20T (99.3 %), Pseudomonas corrugata CFBP 2431T (99.2 %), and Pseudomonas viciae 11K1T (99.2 %) but the 16S rRNA phylogenetic tree displayed a monophyletic clade with Pseudomonas mediterranea CFBP 5447T. In the phylogenetic trees based on sequences of four housekeeping genes (gap1, gltA, gyrB and rpoD), the novel strain formed a separate branch, indicating that the strain was distinct phylogenetically from known species of the genus Pseudomonas . The genome-sequence-derived average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between the novel isolate and P. mediterranea DSM 16733T were 86.7 and 32.7 %, respectively. These values were below the accepted species cutoff threshold of 96 % ANI and 70 % dDDH, affirming that the strain represented a novel species. The genome size of the novel species was 5.98 Mbp with a DNA G+C content of 60.8 mol%. On the basis of phenotypic and genotypic characteristics, strain 20TX0172T represents a novel species of the genus Pseudomonas . The name Pseudomonas uvaldensis sp. nov. is proposed. The type strain is 20TX0172T (=NCIMB 15426T=CIP 112022T).

Whole genome and 16S rRNA dataset of Pectobacterium carotovorum strain 21TX0081 isolated from a symptomatic onion foliage in Texas

“…Bacteria were isolated from ten symptomatic onion foliage and ten onion bulbs collected on May 10, 2021, from an overhead-irrigated onion field . Section of tissue (5 mm 2 ) were cut around the margin of the symptomatic foliage/bulbs, rinsed with sterile water, macerated in 100 µL of sterile water, and streaked on a plate of nutrient agar (NA) using sterile loop [2 , 3] . The plates were incubated in the dark at 28 °C for 48 h. The predominant colonies were purified at least three times.…”

Draft Genome Sequence and Annotation of Pseudomonas carnis Strain 20TX0167, Isolated from an Onion (Allium cepa)

“…The strain grew well on NA medium at 4°C to 30°C but not at 35°C. Its pathogenicity was tested by inoculating 10-μL and 0.5-mL bacterial suspensions (10 8 CFU/mL) onto a detached scale of red onion and into a yellow onion bulb, respectively, and incubated at 25°C, as described earlier ( 3 ). The strain produced a very mild necrosis reaction on the onion scale and bulb assay.…”