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Fungal plant pathogens can present major problems for most crop species. Currently, control of fungal diseases relies heavily on the use of fungicides. However, there are problems associated with fungicide use, including potential toxicity to non-target organisms and the development of resistance in the target fungus. New strategies are being sought to reduce fungicide use. One area of active research is the potential use of antifungal proteins from various fungal species as alternatives or complements to traditional fungicides. An antifungal protein, Efe-AfpA, from the fungal endophyte Epichloë festucae was previously found to protect plants from the pathogen Clarireedia jacksonii, the causal agent of dollar spot disease. Here we report that Efe-AfpA also has inhibitory activity against other important plant pathogens. These results suggest that it may be possible to develop Efe-AfpA as a biofungicide to target a broad range of destructive plant pathogens. [ABSTRACT FROM AUTHOR]

Transgenic herbicide-resistant cultivars of creeping bentgrass (Agrostis stolonifera L.) have been developed and are being considered for commercial release. Concerns regarding transgenic species include potential for outcrossing of the crop, which may produce novel genotypes with increased weediness. Persistence and multiyear growth of interspecific hybrids between creeping bentgrass and velvet bentgrass (A. canina L.), colonial bentgrass (A. capillaris L.), dryland bentgrass (A. castellana Boiss. and Reut.), and redtop bentgrass (A. gigantea Roth) and the backcross progeny of the hybrids were compared with the parental species in field experiments. The plants were evaluated over 2 yr in residential Kentucky bluegrass (Poa pratensis L.) and a low maintenance roadside turf of mixed species. With the exception of redtop bentgrass by creeping bentgrass interspecific hybrids, all interspecific hybrids between creeping bentgrass and colonial, dryland, and velvet bentgrasses were equally or less competitive relative to their parental species. Backcross progeny of interspecific hybrids, including those of redtop bentgrass by creeping bentgrass hybrids, were equally or less competitive than parental species. Bentgrasses that were highly competitive in residential turf were also competitive under roadside maintenance, suggesting bentgrasses have weediness potential regardless of management intensity. doi: 10.2135/cropsci2008.07.0431

Interspecific hybridization is a widely used approach to improve crop species. We are pursuing the possibility of using interspecific hybridization between the turfgrass species colonial bentgrass (Agrostis capillaris L.) and creeping bentgrass (A. stolonifera L.) for the improvement of resistance to the fungal disease dollar spot (Sclerotinia homoeocarpa F.T. Bennett) in creeping bentgrass. From a field evaluation of a backcross population, it appears that introgression of dollar spot resistance from colonial bent-grass to creeping bentgrass is possible. We used the backcross population to generate the first genetic linkage map for colonial bentgrass. The map length was 1156 cM and consisted of 212 amplified fragment length polymorphic markers and 110 gene-based markers. Colonial bentgrass is an allotetraploid species (2n = 4x = 28, [A.sub.1] and [A.sub.2] subgenomes). The map consisted of the expected 14 linkage groups, which could be assigned to either the [A.sub.1] or [A.sub.2] homoeologous subgenomes. Although there were dollar spot resistant individuals in the mapping population, no quantitative trait loci associated with resistance were detected.

Infection of turf and forage grasses with Acremonium Link:Fr. and Epichloe (Fr.) Tul. & C. Tul. fungal endophytes is often desirable because it confers enhanced insect tolerance to these plants. Determination of the viability of the endophytes in seed lots is important for commercial producers and consumers of seed. A current method of determining viability relies on staining leaf sheath epidermal peels for the presence of endophyte hyphae. It is difficult to obtain an epidermal peel from a young seedling, so plants must often be grown for several months before checking for viability. The objective of this study was to develop a method of screening very young seedlings for endophyte viability. Here it is reported that endophyte viability could be determined within 2 to 3 wk of germination by staining intact leaf sheath tissue with an alkaline rose bengal stain. This method of endophyte detection allows a more rapid assessment of percentage of viable endophyte in a seed lot.