Phylodynamic Insights into Global Emergence and Diversification of the Tomato Pathogen pv. .

The emergence of plant pathogens is often associated with waves of unique evolutionary and epidemiological events. pv. is one of the major pathogens causing bacterial spot disease of tomatoes.

Population Genomics Reveals an Emerging Lineage of on Pepper.

-the dominant causal agent of bacterial leaf spot of tomato-is an emerging pathogen of pepper, indicative of a potential host expansion across the southeastern United States. However, studies of the genetic diversity and evolution of from pepper remain limited. In this study, the whole-genome sequences of 35 strains isolated from pepper from four fields and two transplant facilities across southwest Florida between 2019 and 2021 were used to compare genomic divergence, evolution, and variation in type III secreted effectors.

Tomato Domestication Attenuated Responsiveness to a Beneficial Soil Microbe for Plant Growth Promotion and Induction of Systemic Resistance to Foliar Pathogens.

Crop domestication events followed by targeted breeding practices have been pivotal for improvement of desirable traits and to adapt cultivars to local environments. Domestication also resulted in a strong reduction in genetic diversity among modern cultivars compared to their wild relatives, though the effect this could have on tripartite relationships between plants, belowground beneficial microbes and aboveground pathogens remains undetermined. We quantified plant growth performance, basal resistance and induced systemic resistance (ISR) by , a beneficial soil microbe against , a necrotrophic fungus and , a hemi-biotrophic oomycete, in 25 diverse tomato genotypes.

Differential Life History Trait Associations of Aphids with Nonpersistent Viruses in Cucurbits.

The diversity of vectors and fleeting nature of virus acquisition and transmission renders nonpersistent viruses a challenge to manage. We assessed the importance of noncolonizing versus colonizing vectors with a 2-yr survey of aphids and nonpersistent viruses on commercial pumpkin farms. We quantified aphid alightment using pan traps, while testing leaf samples with multiplex RT-PCR targeting cucumber mosaic virus (CMV), zucchini yellow mosaic virus (ZYMV), watermelon mosaic virus (WMV), and papaya ringspot virus (PRSV).

First Report of Black Leg of Hydroponic Basil in the United States Caused by Plectosporium tabacinum.

During August 2007 and again in January 2008, compact sweet basil (Ocimum basilicum 'Genovese') plants grown hydroponically in Indiana displayed dark, irregular, stem lesions extending 2 to 3 cm above the interface of the nutrient solution. These necrotic stem lesions (black leg), observed on 20 to 30% of the basil plants caused very weak, brittle stems so that they could not be marketed fresh. Although no wilting was noted, reduced plant height was observed.