Molecular Characterization and Pathogenicity of Causing Red Rot on Sugarcane in Southern Florida.

Red rot disease reduces sugarcane yield and impacts the sugar quality, posing an important threat to the sugarcane industry in Florida. Although , the causal agent of red rot in Florida, was first reported in 1984 based on morphology, molecular and pathological data have remained limited, highlighting the critical need for comprehensive characterization. Thirteen isolates were obtained from three local sugarcane varieties in Belle Glade, Florida.

f. sp. Race 4 Threatening Celery Production in South Florida.

Fusarium wilt, caused by f. sp. (), is a vascular disease affecting celery.

Detached Maize Sheaths for Live-Cell Imaging of Infection by Fungal Foliar Maize Pathogens.

We have optimized a protocol to inoculate maize leaf sheaths with hemibiotrophic and necrotrophic foliar pathogenic fungi. The method is modified from one originally applied to rice leaf sheaths and allows direct microscopic observation of fungal growth and development in living plant cells. Leaf sheaths collected from maize seedlings with two fully emerged leaf collars are inoculated with 20 µL drops of 5 x 10 spores/mL fungal spore suspensions and incubated in humidity chambers at 23 °C under continuous fluorescent light.

Widespread QoI Fungicide Resistance Revealed Among Tomato Isolates in Florida.

Target spot of tomato caused by is one of the most economically destructive diseases of tomato in Florida. A collection of 123 isolates from eight counties in Florida were evaluated for sensitivity to azoxystrobin and fenamidone based on mycelial growth inhibition (MGI), spore germination (SG), detached leaflet assays (DLAs), and sequence-based analysis of the cytochrome b gene (). Cleavage of by restriction enzyme (4HI) revealed the presence of a mutation conferring a glycine (G) to alanine (A) mutation at amino acid position 143 (G143A) in approximately 90% of the population, correlating with quinone outside inhibitor (QoI) resistance based on MGI (<40% at 5 μg/ml), SG (<50% at 1 and 10 μg/ml), and DLA (<10% severity reduction).