Insect tripping might enhance seed production in common bean (Phaseolus vulgaris L.). The effect of flower visits by insects on seed production was studied during 3 yr, 1992 to 1994, in Riverside, CA, using four cultivars with different growth habits: Linden, Pindak, PI 164778, and Ferry Morse 53 (FM 53). Each year, a factorial experiment in a randomized complete block design with four replicates was used. Each cultivar was grown under three treatments: (i) exposed to open visitation by all insects, (ii) in insect‐proof cages, and (iii) in cages with bumblebees. All pods produced by bean plants were collected and counted, and seed yield was determined. Year‐to‐year variation had signiticant impact on cultivar performance and treatment effects. The bean lines were significantly different for seed yield. The treatment effects were not consistent across years. The old cultivar FM 53 and line PI 164778 had no clear trend for seed yield response to insect visits across years, whereas Linden and Pindak showed a more defined and positive response to visits. Seed yield of Linden was similar in the open visitation and caged‐with‐bumblebees treatments but was significantly higher than that of caged plants, by 13% in 1992 and by 35% in 1994. Pindak showed a 9% increase in seed yield when plants were visited by insects in the open or in caged treatments compared with caged plants in 1992. The results indicate that cultivars such as Linden and Pindak, which behave as determinate plants, may respond to bumblebee tripping by increasing seed yield.

In people, colonization with Clostridioides difficile , the leading cause of antibiotic-associated diarrhea, has been shown to be associated with distinct gut microbial features, including reduced bacterial community diversity and depletion of key taxa. In dogs, the gut microbiota features that define C . difficile colonization are less well understood. We sought to define the gut microbiota features associated with C . difficile colonization in puppies, a population where the prevalence of C . difficile has been shown to be elevated, and to define the effect of puppy age and litter upon these features and C . difficile risk. We collected fecal samples from weaned (n = 27) and unweaned (n = 74) puppies from 13 litters and analyzed the effects of colonization status, age and litter on microbial diversity using linear mixed effects models. Colonization with C . difficile was significantly associated with younger age, and colonized puppies had significantly decreased bacterial community diversity and differentially abundant taxa compared to non-colonized puppies, even when adjusting for age. C . difficile colonization remained associated with decreased bacterial community diversity, but the association did not reach statistical significance in a mixed effects model incorporating litter as a random effect. Even though litter explained a greater proportion (67%) of the variability in microbial diversity than colonization status, we nevertheless observed heterogeneity in gut microbial community diversity and colonization status within more than half of the litters, suggesting that the gut microbiota contributes to colonization resistance against C . difficile . The colonization of puppies with C . difficile has important implications for the potential zoonotic transfer of this organism to people. The identified associations point to mechanisms by which C . difficile colonization may be reduced.

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Avibacterium paragallinarum (historically called Hemophilus paragallinarum) causes infectious coryza (IC), which is an acute respiratory disease of chickens. Recently, outbreaks of IC have been reported in Pennsylvania (PA) in broilers, layer pullets, and laying hens, causing significant respiratory disease and production losses. A tentative diagnosis of IC can be made based on history, clinical signs, and characteristic gross lesions. However, isolation and identification of the organism are required for a definitive diagnosis. Major challenges with the bacteriological diagnosis of A. paragallinarum include that the organism is difficult to isolate, slow-growing, and can only be successfully isolated during the acute stage of infection and secondary bacterial infections are also common. As there were very limited whole genomes of A. paragallinarum in the public databases, we carried out whole-genome sequencing (WGS) of PA isolates and based on the WGS data analysis; we designed a novel probe-based PCR assay targeting a highly conserved sequence in the recN, the DNA repair protein gene of A. paragallinarum. The assay includes an internal control, with a limit of detection (LOD) of 3.93 genomic copies. The PCR efficiency ranged between 90 and 97%, and diagnostic sensitivity of 98.5% compared with conventional gel-based PCR. The test was highly specific, and no cross-reactivity was observed with other species of Avibacterium and a range of other common poultry respiratory viral and bacterial pathogens. Real-time PCR testing on 419 clinical samples from suspected flocks yielded 94 positives and 365 negatives in agreement with diagnostic bacterial culture-based detection. We also compared the recN PCR assay with a previous HPG-2 based real-time PCR assay which showed a PCR efficiency of 79%.

ABSTRACT Avibacterium paragallinarum, the causative agent of infectious coryza, causes significant economic losses to the poultry industry due to increased culling rates in growing chickens and decreased egg production in layers. We present the complete genome sequences of seven strains of Avibacterium paragallinarum isolated from poultry farms in Pennsylvania during 2019.