Bermudagrass (Cynodon spp.) is often overseeded with a cool-season turfgrass to provide a green, actively growing surface for winter and early-spring sporting activities. Two grass species that have ...not been tested for overseeding include tetraploid (2n = 4x = 28) perennial ryegrass (Lolium perenne L.) and meadow fescue (Festuca pratensis Huds.). The objectives of this study were to test these two species in comparison to three standard overseeding species diploid perennial ryegrass, intermediate ryegrass (L. perenne x L. multiflorum Lam.), and Poa trivialis L. in three environments; Maricopa, AZ (arid), Fayetteville, AR (transition zone), and Auburn, AL (humid, subtropical). At all locations, overseeding grasses were seeded into dormant bermudagrass turf and managed according to standard overseeding practices. The tetraploid ryegrass had equal or superior turfgrass quality to all other overseeding species except the diploid ryegrass. Meadow fescue produced similar turfgrass quality to intermediate ryegrass and tetraploid ryegrass at Arkansas and Alabama, but had lower turf quality scores in Arizona. The meadow fescue and tetraploid ryegrass transitioned more quickly back to bermudagrass compared to the diploid ryegrass, intermediate ryegrass, and P. trivialis, which would be very favorable aspects of these new overseeding grasses. These trials clearly demonstrate the potential of two new species, meadow fescue and tetraploid ryegrass, for overseeding dormant bermudagrass turf.
Leaf tissue of tall fescue Festuca arundinacea Schreb., hard fescue Festuca ovina L., red fescue Festuca rubra L. and perennial ryegrass Lolium perenne L. was stained with rose Bengal or aniline blue ...to detect the presence of the fungal endophyte Acremonium sp., Specimens were cleared using methyl salicylate, an optical clearing agent, and viewed using bright field microscopy. Tissue was presenred as dried tissue or stored in 70% aqueous ethyl alcohol before staining and clearing. Tissue was observed at 2, 4 and 12 weeks following clearing to check for stain retention. Staining with rose Bengal was inferior to aniline blue when followed by the clearing agent methyl salicylate. Fungal mycelia stained lighter with rose Bengal and were more difficult to detect than mycelia stained with aniline blue. The results illustrate the usefulness of combining staining and methyl salicylate clearing for detecting fungal endophytes.
Control of ergot in buffelgrass with triadimefon Craig, J. (Southern Crops Germplasm Research Unit, ARS, USDA, College Station, TX); Hignight, K.W
Plant disease,
06/1991, Letnik:
75, Številka:
6
Journal Article
Experiments were carried out in New Mexico to determine whether the electrification processes that lead to the formation of lightning in clouds are influenced by the polarity of the charges in the ...air from which the clouds grow. The normal, positive space charge in the sub-cloud air was reversed by negative charge released from an electrified wire, suspended across a 2-kilometer-wide canyon. On more than four occasions when the clouds over the wire grew and became electrified, they were of abnormal polarity with dominant positive charges instead of the usual negative charges in the lower part of the cloud. The formation of these abnormally electrified clouds suggests both that the electrification process in thunderclouds can be initiated and that its polarity may be determined by the small charges that are present in the atmosphere.
