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Bacterial diseases pose a severe challenge to growers and cause significant loss to the billion-dollar onion industry in the United States. Texas is the sixth largest onion producing state, yet the bacterial communities associated with short-day onion crops grown in Texas have not been studied. This study was conducted to identify, characterize, and understand the diversity of bacteria associated with onion production in Texas. In 2020, 190 foliar and 210 bulb samples were collected from onion crops in the Rio Grande Valley and Winter Garden regions of Texas. Sequencing of the 16s rRNA gene was used to identify each bacterial strains to a genus. The pathogenicity to onion of each bacterial strain was tested using three assays: a red onion scale assay, a yellow onion bulb assay, and a foliar assay. Whole genome sequencing was done to identify the onion-pathogenic strains to species. Collectively, isolates of 24 genera belonging to three phyla were detected, including 19 genera from foliar samples and nine genera from bulb samples. Isolates in the Phylum Proteobacteria, including 15 genera of Gram-negative bacteria, were the most abundant of the taxa, comprising 90.0% of the strains isolated. The diversity of foliar isolates was evenly distributed between Gram-positive and Gram-negative bacteria, while Gram-negative bacteria dominated the isolates from bulb samples. In total, 83.9% of the bacterial isolates were not pathogenic on onion, with only isolates of Pantoea , Pseudomonas , Burkholderia , Erwinia , Enterobacter , and Curtobacterium proving pathogenic. Strains of Burkholderia gladioli , Pseudomonas alliivorans , Pantoea agglomerans , P . ananatis , and P . allii are the first documented cases of these pathogens of onion in Texas. Identifying and characterizing the nature of onion microflora, including pathogens of onion, is vital to developing rapid disease detection techniques via pathogenomics and minimizing losses through the application of effective disease management measures., Competing Interests: The author(s) declare no conflict of interest.

A Gram-stain-positive, aerobic, and non-spore-forming bacterial strain, 20TX0166 T , was isolated from a diseased onion bulb in Texas, USA. Upon testing its pathogenicity on onion bulb, it produced pathogenic response which makes it first species of pathogen belonging to the phylum actinobacteria detected in onion. Phylogenetic analysis of the 16S rRNA gene sequence revealed that the strain belonged to the genus Curtobacterium and was most similar to Curtobacterium flaccumfaciens LMG 3645 T (100%), C. pusillum DSM 20527 T (99.5%), and C. oceanosedimentum ATCC 31317 T (99.5%). The estimated genome size of the novel species was 4.0 Mbp with a G + C content of 70.8%. The orthologous ANI (orthoANIu), ANI based on blast (ANIb), and dDDH values between the novel strain and the closest relative, C. flaccumfaciens LMG 3645 T , were 95.7%, 95.4%, and 63.3%, respectively. These values were below the recommended species cut-off threshold of 96% (ANI) and 70% (dDDH), suggesting the strain may be a novel species. Physiologic and phenotypic characters of this novel strain were also unique when compared with the closely related species. The major cellular fatty acids of this strain were anteiso-C 15:0 and anteiso-C 17:0 . Using a polyphasic approach based on phenotypic and genotypic analyses, strain 20TX0166 T represents a novel species of the genus Curtobacterium, and the name Curtobacterium allii sp. nov. is proposed. The type strain is 20TX0166 T (= LMG 32517 T  = CIP112023 T  = NCIMB 15427 T )., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Bacterial soft rot is an important disease in onion caused by Pectobacterium carotovorum , a Gram-negative bacterium belonging to the Pectobacteriaceae family. The soft rot disease may occur during the preharvest (mature bulbs) or postharvest (transit, storage) stage. We collected symptomatic onion plants from the field and isolated bacteria from the foliage and bulbs. We extracted genomic DNA from the bacterial strain 21TX0081 isolated from onion foliage, conducted a polymerase chain reaction (PCR) based on 16S ribosomal RNA (rRNA)-specific primers, and classified the strain to genus Pectobacterium . To ascertain the species, genome features, and novelty of the strain, we conducted whole genome sequencing and computed average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values. We also annotated the genome of P. carotovorum strain 21TX0081 using Rapid Annotation using Subsystem Technology (RAST) server. The raw, untrimmed forward and reverse sequence reads of 16S rRNA, and whole genome annotation features have been deposited at Mendeley Data. The datasets generated from consensus 16S rRNA and whole genome sequence have been deposited in National Center for Biotechnology Information (NCBI) repository. They will be useful for future research on comparative genomics and developing tools for disease management in onion., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Author(s).)

Anthracnose of watermelon is caused by a fungal pathogen Colletotrichum orbiculare . We generated F 2 individuals from three different populations: Population 1 (PI 189225 x 'New Hampshire Midget'), Population 2 ('Perola' x PI 189225), and Population 3 ('Verona' x PI 189225). The biparental F 2 populations, parents and F 1 individuals were inoculated with an isolate of race 2 anthracnose isolated from watermelon. Leaf lesions were visually rated seven days post inoculation on a scale of 0% (no lesion) to 100% (dead true leaf). Here we present the datasets obtained after the disease inoculation. The distribution of data obtained was visualized using histograms and goodness-of-fit was tested using Chi-Square. These datasets provide information on the mode of inheritance of race 2 anthracnose resistance in watermelon., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Author(s).)

A Gram-stain-negative, aerobic and non-spore-forming bacterial strain, designated 20TX0172 T , 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 520-20 T (99.3 %), Pseudomonas corrugata CFBP 2431 T (99.2 %), and Pseudomonas viciae 11K1 T (99.2 %) but the 16S rRNA phylogenetic tree displayed a monophyletic clade with Pseudomonas mediterranea CFBP 5447 T . 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 16733 T 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 20TX0172 T represents a novel species of the genus Pseudomonas . The name Pseudomonas uvaldensis sp. nov. is proposed. The type strain is 20TX0172 T (=NCIMB 15426 T =CIP 112022 T ).

Horticultural crops include a diverse array of crops comprising fruits, vegetables, nuts, flowers, aromatic and medicinal plants. They provide nutritional, medicinal, and aesthetic benefits to mankind. However, these crops undergo many biotic (e.g., diseases, pests) and abiotic stresses (e.g., drought, salinity). Conventional breeding strategies to improve traits in crops involve the use of a series of backcrossing and selection for introgression of a beneficial trait into elite germplasm, which is time and resource consuming. Recent new plant breeding tools such as clustered regularly interspaced short palindromic repeats (CRISPR) /CRISPR-associated protein-9 (Cas9) technique have the potential to be rapid, cost-effective, and precise tools for crop improvement. In this review article, we explore the CRISPR/Cas9 technology, its history, classification, general applications, specific uses in horticultural crops, challenges, existing resources, associated regulatory aspects, and the way forward.

Promotion of low-skilled off-farm rural labor market participation can be an important strategy to improve livelihoods and food security of the poor in developing countries. This paper investigates rural farm households' participation in low-skilled off-farm labor markets with disaggregate data from a survey of 400 households in Tigray, the northern highlands of Ethiopia. Adopting Heckman's two stage approach, we examined households' decisions to participate or not in markets by probit model in the first stage and level of participation by ordinary least squares procedures in the second stage. The results show that households' decision to enter into a labor market significantly depends on the characteristics of the households such as sex, age of the household heads and labor endowments in the households. Similarly, the level of participation in labor markets measured by the amount of off-farm wage income depends on labor endowments in the households and the place where the households are located. Since cash constrained rural households do not find themselves advantageous to participate in off-farm labor markets, the reduction of cash constraint is the major policy implication of the paper. This holds true in general for all cash constrained rural households in developing countries. Similarly, the empirical results in the paper suggest removal of locational barriers to access labor markets. This helps them to earn off-farm income. It is necessary to eliminate (or at least reduce) obstacles for rural households to enter into a market of off-farm wage earning activities. This holds true in general for all rural households in developing countries. This paper is therefore expected to contribute to frame appropriate policy that promotes participation in low-skilled off-farm rural labor markets in developing countries where many rural households are not only poor but also low-skilled.