Multilocus Sequence Typing of Strains of Bacterial Spot of Lettuce Collected in the United States.

Studies on genetic diversity and recombination in bacterial pathogens are providing a better understanding of the mechanisms shaping bacterial diversity, which can affect disease control. Xanthomonas campestris pv. vitians, causal agent of bacterial leaf spot of lettuce, is a threat to the worldwide lettuce industry.

Host specialization and phylogenetic diversity of Corynespora cassiicola.

The fungus Corynespora cassiicola is primarily found in the tropics and subtropics, and is widely diverse in substrate utilization and host association. Isolate characterization within C. cassiicola was undertaken to investigate how genetic diversity correlates with host specificity, growth rate, and geographic distribution.

Evidence for the Preemptive Nature of Tomato Race 3 of Xanthomonas campestris pv. vesicatoria in Florida.

ABSTRACT Until recently, tomato race 1 (T1) of Xanthomonas campestris pv. vesicatoria was the only race causing bacterial spot of tomato in Florida. In 1991, tomato race 3 (T3) was first identified in 3 of 13 tomato production fields surveyed.

First Report of a Leaf Spot Disease of Wild Rocket (Diplotaxis tenuifolia) in Florida Caused by Xanthomonas campestris pv. raphani.

Wild rocket, also known as wall rocket or sand rocket (Diplotaxis tenuifolia (L.) DC, family Brassicaceae), is grown in Florida as a salad green and herb, especially for addition to "spring mix" and other bagged salad blends. It is similar in texture and flavor to the more widely known garden arugula (Eruca vesicatoria (L.

First Report of Powdery Mildew of Parsley Caused by Erysiphe heraclei in Florida.

Parsley (Petroselinum crispum (Mill.) Nym. ex A.

Bacterial Leaf Spot of Lettuce: Relationship of Temperature to Infection and Potential Host Range of Xanthomonas campestris pv. vitians.

Epidemiological aspects, including optimum temperature for infection and host range of Xanthomonas campestris pv. vitians, causal organism of bacterial leaf spot (BLS) of lettuce, were investigated. The optimum temperature for infection was determined to be 22.

Outbreak of Choanephora Blight Caused by Choanephora cucurbitarum on Green Bean and Pepper in Florida.

Severe outbreaks of Choanephora blight on green bean (Phaseolus vulgaris cvs. Bronco, Shade, and Gold Mine) and bell pepper (Capsicum annuum cvs. Aristotle, Crusader, and Sentry) were widespread in southwestern (Hendry and Collier counties) and northern Florida (Alachua County) in October and November 2002.

An Outbreak of a Leaf Spot Disease of Cabbage in Southern Florida Caused by Xanthomonas campestris pv. armoraciae.

From October to December 2001, a leaf spot disease was observed in numerous commercial fields of red and green cabbage (Brassica oleracea var. capitata L.) in the Everglades Agricultural Area, south and east of Lake Okeechobee and in the environs of Immokalee in southwestern Florida.

Investigation of Seed Treatments for Management of Bacterial Leaf Spot of Lettuce.

Chemical seed treatments were evaluated for efficacy of disinfestation of lettuce seed that had been inoculated with Xanthomonas campestris pv. vitians. Three concentrations of each chemical were evaluated by treating seed lots for 5 or 15 min.

Occurrence of Bacterial Leaf Spot of Escarole Caused by Pseudomonas cichorii in the Everglades Agricultural Area of Southern Florida.

In the fall of 1997, 1998, and 2000, a leaf spot disease of escarole (Cichorium endivia L.) was widespread among commercial plantings in the Everglades Agricultural Area (EAA), south and east of Lake Okeechobee, FL. Symptoms consisted of dry, dark gray-to-black lesions that expanded to ≈4 cm in diameter.

A Serious Outbreak of Race 6 of Xanthomonas campestris pv. vesicatoria on Pepper in Southern Florida.

In the 1997-1998 winter vegetable season, a widespread and serious outbreak of bacterial spot occurred on pepper in commercial fields throughout southern Florida. This was the first serious epidemic of bacterial spot on pepper in southern Florida since the 1993-1994 season. Cultivars affected included those with resistance to races 1-3 of X.

Powdery Mildew of Field-Grown Tomato in Florida.

Powdery mildew was observed affecting mature, field-grown, fresh-market tomatoes in southeastern Florida (St. Lucie, Martin, Palm Beach, and Broward counties). Outbreaks were noted in May of 1996 and throughout the spring of 1997.

Epiphytic Populations of Xanthomonas campestris pv. vesicatoria on Pepper: Relationships to Host-Plant Resistance and Exposure to Copper Sprays.

Epiphytic populations of Xanthomonas campestris pv. vesicatoria were monitored on leaves and in buds of resistant and susceptible pepper cultivars over five seasons. Epiphytic populations were higher on the susceptible cultivar Jupiter than on the resistant cultivar Boynton Bell in four of the five seasons.

Bacterial Leaf Spot of Cilantro in Florida.

In the 1995 to 1996 winter vegetable season, a leaf spot disease of cilantro (fresh coriander) (Coriandrum sativum L.) was widespread throughout commercial plantings in the Everglades Agricultural Area south and east of Lake Okeechobee. Symptoms first appeared as water-soaked spots ≤1 mm in diameter.