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Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2017

To document

Abstract

Invasion of annual bluegrass (Poa annua L.) is a major concern on red fescue (Festuca rubra L.) putting greens. Our objective was to determine the effect of three seasonal fertilizer distribution treatments on red fescue turf quality and annual bluegrass encroachment. The experiment was conducted over 2 yr on a USGA-specified putting green at NIBIO Turfgrass Research Center Landvik, Norway (58° N). A complete liquid fertilizer was applied weekly for an annual nitrogen input of 11 g m−2 in all treatments. In the FLAT rate treatment, the weekly fertilizer rate was 0.45 g N m−2 wk−1 from 5 May to 28 September. The FALL+ treatment received 0.68 g N m−2 wk−1 from 11 August to 28 September and 0.23 g N m−2 wk−1 from 5 May to 21 June, whereas the SPRING+ treatment was the opposite. The SPRING+ fertilization resulted in significantly better turf quality and significantly less annual bluegrass than the two other treatments in the second year of the study. The FALL+ fertilization gave higher quality ratings in the fall and early spring, but this effect came at the expense of more annual bluegrass. In conclusion, we recommend a fertilizer regime with the highest input from early May until midsummer to produce red fescue putting greens with the highest possible turfgrass quality and minimal encroachment by annual bluegrass.

To document

Abstract

Conversion from annual bluegrass or bentgrasses to red fescue could be an efficient way to minimise water use on golf greens. Our objective was to investigate the influ- ences of four irrigation strategies on red fescue water use efficiency, turf quality, growth rate and resistance to annual bluegrass and moss invasion. The trial was car- ried out from August 2013 to August 2015 on a green established according to USGA recommendations under a rainout shelter at Landvik, Norway (58 ° N). On average for 2 years, irrigation to field capacity once per week (FC 1) and deficit irrigation to 60% of FC three times per week (DEF 3) reduced the water consumption by 49% and 72% relative to irrigation to FC three times per week (FC 3). Both DEF 3 and FC 1 retained acceptable turf quality and reduced annual bluegrass in the second year by about one-third. Better control of annual bluegrass was obtained with deficit irrigation to 60% of FC once per week (DEF 1), but this treatment did not produce acceptable turf quality. Compared with FC 3, DEF 3, FC 1 and DEF 1 gave harder surfaces and reduced the moss invasion in the second year by 66%, 90% and 93%, respectively. Irrigation effects on root development and thatch organic matter after 2 years were not significant, although the thatch layer depth was 3 – 4 mm greater in FC 1 than in the other treatments. In conclusion, DEF 3 and FC 1 are both effective irrigation strategies for managing red fescue greens with less water use.

2016

Abstract

Microdochium nivale (Fries) Samuels & Hallett is an important turfgrass pathogen on golf courses. Our objective was to evaluate Gliocladium catenulatum Gilman & Abbott and/or Streptomyces species for biological control of M. nivale on golf greens. The microbial agents were tested relative to fungicides and an untreated control in vitro and in five field trials from 2011 to 2014. G. catenulatum (Turf G+/WPG, Verdera OY, Finland) was applied from October to December and in March–April, while Streptomyces species (Turf S+/WPS, same manufacturer) was applied from May to October, both at four week intervals. In vitro, Streptomyces species suppressed the growth of M. nivale at 6 and 16°C, while G. catenulatum suppressed growth of M. nivale at 16°C only. In contrast, neither product, nor their combination, had any consistent effect in the field trials. A statistically significant reduction in Microdochium patch (from 3 to 2% of plot area) was seen in a trial on a green dominated by Festuca rubra L., but this reduction was deemed to be of little practical interest to the greenkeeper. Despite multiple applications over 3 yr to build up an antagonistic microflora, only fungicides reduced M. nivale significantly on greens dominated by Poa annua L. or Agrostis capillaris L., which generally had more disease. In conclusion, this research showed no potential of G. catenulatum or Streptomyces species to replace fungicides for control of M. nivale on northern-latitude golf greens.