Resistance of Prairie Junegrass and Tufted Hairgrass Germplasm to Diseases Common in Temperate Low-Input Turfgrass Systems

Prairie junegrass and tufted hairgrass are two turfgrass species that are native to the United States and require less water, fertilizer, and pesticide compared with more commonly used turfgrass species such as Kentucky bluegrass. However, little is known about the resistance of these low-input turfgrasses to common turfgrass diseases. The primary objective of this research was to identify disease-resistant germplasm of both prairie junegrass and tufted hairgrass that can be used in future low-input turfgrass breeding efforts. A total of 41 populations of tufted hairgrass and 23 populations of prairie junegrass were evaluated for resistance to Microdochium patch, dollar spot, and rust development in a controlled environment. Genetic variation in disease resistance was clearly present in the unimproved germplasm of both prairie junegrass and tufted hairgrass, providing important direction for future breeding efforts that will allow wider implementation of low-input turfgrass species.

Screening Bermudagrass Germplasm Accessions for Tolerance to Sting Nematodes

Breeding and improvement of new bermudagrass (Cynodon spp.) cultivars with superior nematode tolerance are essential because sting nematode (Belonolaimus longicaudatus Rau) is a major limitation for use of bermudagrass in the sandy coastal soils of the southeastern United States. The screening of both African (Cynodon transvaalensis) and common (C. dactylon) bermudagrass is necessary to develop triploid hybrid cultivars. Five commercial cultivars and 46 germplasm accessions of bermudagrass were tested for nematode responses in two greenhouse trials in 2009. Turfgrass was grown in sand-filled plastic conetainers and inoculated with 50 sting nematodes per conetainer. Nematode and root samples were collected 90 d after nematode inoculation. Fifteen bermudagrass accessions did not have measurable root loss from inoculation with sting nematode. Seven bermudagrass accessions, including ‘Celebration’, produced longer roots in sting nematode-infested soil than the standard ‘Tifway’. Differences in final nematode numbers were identified among the genotypes, and different relative responses were identified in variable ploidy levels and origins. This could aid a turfgrass breeding program by elucidating the genetic diversity available for breeding future bermudagrass cultivars for golf course cultivation.