Biocontrol Strains Differentially Shift the Genetic Structure of Indigenous Soil Populations of .

Biocontrol using non-aflatoxigenic strains of has the greatest potential to mitigate aflatoxin contamination in agricultural produce. However, factors that influence the efficacy of biocontrol agents in reducing aflatoxin accumulation under field conditions are not well-understood. Shifts in the genetic structure of indigenous soil populations of following application of biocontrol products Afla-Guard and AF36 were investigated to determine how these changes can influence the efficacy of biocontrol strains in reducing aflatoxin contamination.

Identification of expressed R-genes associated with leaf spot diseases in cultivated peanut.

Peanut (Arachis hypogaea L.) is an important food and oilseed crop worldwide. Yield and quality can be significantly reduced by foliar fungal diseases, such as early and late leaf spot diseases.

Epidemics and Yield Losses due to Corynespora cassiicola on Cotton.

Target spot, caused by Corynespora cassiicola, has recently emerged as a problematic foliar disease of cotton. This pathogen causes premature defoliation during boll set and maturation that can subsequently impact yield, and on certain cotton cultivars loss can be substantial. This study sought to better understand target spot epidemics and disease-incited yield losses on cotton.

Exploring soil bacterial communities in different peanut-cropping sequences using multiple molecular approaches.

Soil bacterial communities have significant influence on soilborne plant pathogens and, thus, crop health. The present study focuses on ribotyping soil bacterial communities in different peanut-cropping sequences in Alabama. The objective was to identify changes in microbial assemblages in response to cropping sequences that can play a role in managing soilborne plant pathogens in peanut.

Synergistic Disease in Pepper Caused by the Mixed Infection of Cucumber mosaic virus and Pepper mottle virus.

ABSTRACT The occurrence of more than one virus species in a single plant is not uncommon in cultivated and native plant species. A mixed virus infection may lead to greater disease severity than individual viral components and this is sometimes referred to as a synergistic disease. Although, in some cases, synergism has been demonstrated for various plant growth parameters such as plant height, weight, and yield, proof of synergy typically has not been demonstrated for symptom severity when the mixed virus infection was not lethal.

Incidence of Viruses Infecting Winter Wheat in Alabama.

The most important viral diseases of wheat are caused by Barley yellow dwarf virus (BYDV, strains PAV and MAV) and Cereal yellow dwarf virus (CYDV, strain RPV). Starting in 2000, winter wheat crops growing in northern, central, and southern Alabama were evaluated for the occurrence of BYDV-PAV and CYDV-RPV. In addition to these viruses, samples were tested for the presence of Soilborne wheat mosaic virus (SBWMV), Wheat spindle streak mosaic virus (WSSMV), and Wheat streak mosaic virus (WSMV).

Cultivar and Spacing Effects on Transmission of Phytophthora parasitica in an Ebb-and-Flow Subirrigation System.

Phytophthora parasitica was transmitted within 6 weeks from vinca (Catharanthus roseus) plants growing in infested potting mix, on the drain end of ebb-and-flow benches, to plants in noninfested potting mix. Transmission of Phytophthora was very low when potting mix was not pasteurized. When potting mix was steam pasteurized, infection of plants, disease incidence, and severity increased with time and decreased with distance from plants in infested pots.