Lightweight Rolling Effects on Anthracnose of Annual Bluegrass Putting Greens

Bispyribac-sodium is an efficacious herbicide for annual bluegrass control in creeping bentgrass fairways, but turf tolerance and growth inhibition may be exacerbated by low mowing heights on putting greens. We conducted field and greenhouse experiments to investigate creeping bentgrass putting green tolerance to bispyribac-sodium. In greenhouse experiments, creeping bentgrass discoloration from bispyribac-sodium was exacerbated by reductions in mowing height from 24 to 3 mm, but mowing height did not influence clipping yields or root weight. In field experiments, discoloration of creeping bentgrass putting greens was greatest from applications of 37 g/ha every 10 d, compared to 74, 111, or 222 g/ha applied less frequently. Chelated iron effectively reduced discoloration of creeping bentgrass putting greens from bispyribac-sodium while trinexapac-ethyl inconsistently reduced these effects. Overall, creeping bentgrass putting greens appear more sensitive to bispyribac-sodium than higher mowed turf, but chelated iron and trinexapac-ethyl could reduce discoloration.

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Annual Bluegrass (Poa Annua) Control in Creeping Bentgrass (Agrostis Stolonifera) Putting Greens with Bispyribac-sodium

Weed Technology ◽

10.1614/wt-06-023 ◽

2007 ◽

Vol 21 (2) ◽

pp. 426-430 ◽

Cited By ~ 7

Author(s):

Travis C. Teuton ◽

Christopher L. Main ◽

John C. Sorochan ◽

J. Scott McElroy ◽

Thomas C. Mueller

Keyword(s):

Creeping Bentgrass ◽

Agrostis Stolonifera ◽

Poa Annua ◽

Putting Greens ◽

Annual Bluegrass

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Pathogenicity of Xanthomonas translucens from Annual Bluegrass on Golf Course Putting Greens

Plant Disease ◽

10.1094/pd-89-0469 ◽

2005 ◽

Vol 89 (5) ◽

pp. 469-473 ◽

Cited By ~ 12

Author(s):

N. A. Mitkowski ◽

M. Browning ◽

C. Basu ◽

K. Jordan ◽

N. Jackson

Keyword(s):

Host Range ◽

Bacterial Wilt ◽

Optimal Growth ◽

Fatty Acid Analysis ◽

Culture Collection ◽

Causal Agent ◽

Significant Similarity ◽

Putting Greens ◽

Annual Bluegrass ◽

Xanthomonas Translucens

Bacterial wilt of Poa annua has been seen increasingly in the Northeast and mid-Atlantic United States in the past few years. The disease causes severe injury to putting greens and can kill large stands of turfgrass. For some time, however, both the bacterial origin of the disease and the causal agent were in doubt. In order to investigate the identity of the causal agent, isolation of the pathogen was undertaken and pathogenicity was confirmed using Koch's postulates on P. annua. Additional pathogenicity trials then were undertaken to determine the host range of the causal bacterium. Ability of the bacterium to cause disease was restricted to P. annua var. annua and P. attenuata. However, the bacterium was able to survive asymptomatically in vascular systems of P. annua var. reptans and P. trivialis. Experiments to determine the optimal growth temperature of the organism demonstrated that the bacterial growth peaked between 30 and 35°C. Fatty acid analysis suggested that the bacterium might be a species of Xanthomonas but was inconclusive. Ribosomal RNA analysis demonstrated significant similarity to the American Type Culture Collection isolate of Xanthomonas translucens pv. poae at 99.8%. Comparison of the host range to previously reported data agrees with our molecular findings and indicates that the likely casual organism of bacterial wilt of annual bluegrass is X. translucens pv. poae.

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Mycorrhizal fungi associated with three species of turfgrass

Canadian Journal of Botany ◽

10.1139/b97-034 ◽

1997 ◽

Vol 75 (2) ◽

pp. 320-332 ◽

Cited By ~ 19

Author(s):

R. E. Koske ◽

J. N. Gemma ◽

N. Jackson

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Creeping Bentgrass ◽

Summer Drought ◽

Putting Greens ◽

Soil P ◽

Annual Bluegrass ◽

Spore Abundance ◽

Amf Communities

Small plots of highly maintained turfs of creeping bentgrass (Agrostis palustris cv. Penncross) and velvet bentgrass (Agrostis canina cv. Kingstown) and a marginally maintained stand of annual bluegrass (Poa annua) were sampled intensively over a 15-month period to measure the populations of spores of arbuscular mycorrhizal fungi (AMF) associated with their root systems. Direct isolation of spores and trap cultures were used to assess the AMF communities. Spores of more than 18 species of AMF were isolated. The six dominant species (as measured by the abundance and frequency of occurrence of spores) were Acaulospora mellea, an undescribed species of Acaulospora, Scutellospora calospora, Glomus occultum, Glomus etunicatum, and Entrophospora infrequens. Spores of 17 species of AMF were recovered from the root zones of velvet bentgrass, 15 species from creeping bentgrass, and 14 from annual bluegrass. Soil fertility differed among the three sites, and it was not possible to ascribe differences in the AMF communities in each plot to any particular variable (e.g., host, pH, soil P). Average spore abundance was greatest in the creeping bentgrass plot (191.0 spores/100 mL), next in the velvet bentgrass plot (82.4 spores/100 mL), and least in the bluegrass plot (28.4 spores/100 mL). Spores were recovered from a significantly greater percentage of the samples from the bentgrass plots (88.5 – 96.8%) than from the bluegrass plot (76.6%). Spores of an average of 4.5 species of AMF were isolated monthly from creeping bentgrass, 3.3 from velvet bentgrass and 2.0 from bluegrass. Average species richness and spore abundance were positively correlated in the creeping bentgrass and bluegrass plots (r = 0.77, p = 0.001, and r = 0.68, p = 0.006), but not in the velvet bentgrass plot. Spore abundance showed strong seasonal trends in all three plots (p = 0.03 – 0.001), with numbers increasing from spring until November. Richness and abundance declined from December until the following spring. In the bluegrass area, which experienced summer drought, spore populations and richness also showed a precipitous decline in July and August in the 1st year of the study (1990), but not in the 2nd year (1991). No such summer decline occurred in the bentgrass plots that received irrigation. The AMF community that was circumscribed by direct spore counts from the field usually was highly dissimilar to the community that was estimated by trap cultures initiated using soil from the turf areas. Key words: annual bluegrass, arbuscular mycorrhizal fungi, creeping bentgrass, putting greens, turfgrass, velvet bentgrass.

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Long-Term Roughstalk Bluegrass Control in Creeping Bentgrass Fairways

Weed Technology ◽

10.1017/wet.2017.72 ◽

2017 ◽

Vol 31 (5) ◽

pp. 714-723

Author(s):

Sandeep S. Rana ◽

Shawn D. Askew

Keyword(s):

Creeping Bentgrass ◽

Golf Course ◽

Cool Season ◽

Putting Greens ◽

Annual Bluegrass ◽

Turf Quality ◽

Normalized Difference Vegetative Index

Methiozolin is an isoxazoline herbicide that selectively controls annual bluegrass in cool-season turf and may control roughstalk bluegrass, another weedyPoaspecies that is problematic in many turfgrass systems. However, the majority of research to date is limited to evaluating methiozolin efficacy for annual bluegrass control in creeping bentgrass putting greens. Research was conducted comparing various application regimes of methiozolin and other herbicides for long-term roughstalk bluegrass control in creeping bentgrass golf fairways. Methiozolin-only treatments did not injure creeping bentgrass or reduce normalized difference vegetative index (NDVI) at 2 golf course locations based on 20 evaluation dates over a 2.5-yr period. The 2.5-yr average turf quality generally declined as roughstalk bluegrass control increased due to transient turf cover loss. At 1 yr after last treatment, methiozolin at 1500 g ai ha-1applied four times in fall reduced roughstalk bluegrass cover 85%. This was equivalent to methiozolin at 1000 g ha-1applied four times in fall, but greater than low rates of methiozolin applied four times in spring or twice in fall and spring. Amicarbazone, primisulfuron, and bispyribac-sodium alone either did not effectively reduce roughstalk bluegrass cover, or did so at the expense of increased creeping bentgrass injury. Results of this study suggest that methiozolin alone or tank-mixed with amicarbazone or primisulfuron is an effective long-term approach for selectively controlling roughstalk bluegrass in creeping bentgrass.

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Annual Bluegrass and Creeping Bentgrass Response to Varying Levels of Iron

HortScience ◽

10.21273/hortsci.36.2.371 ◽

2001 ◽

Vol 36 (2) ◽

pp. 371-373 ◽

Cited By ~ 12

Author(s):

Xia Xu ◽

Charles F. Mancino

Keyword(s):

Root Growth ◽

Creeping Bentgrass ◽

Dry Weight ◽

Sand Culture ◽

Treatment Level ◽

Invasive Weed ◽

Putting Greens ◽

Annual Bluegrass ◽

Shoot Dry Weight ◽

Half Strength

Many biotypes of annual bluegrass (Poa annua L.) are found on golf course putting greens. Although normally considered an invasive weed, annual bluegrass can provide as good a putting surface as creeping bentgrass (Agrostis palustris Huds.). The most desirable biotypes of annual bluegrass are primarily vegetative and have a low flowering frequency. Whether the nutritional requirements of annual bluegrass biotypes differ from one another or from creeping bentgrass is unknown. The response of three flowering (FAB, high seedhead production) and three vegetative (VAB, low seedhead production) biotypes of annual bluegrass (AB), and the three parents of `Penncross' creeping bentgrass (CB) to varying levels of iron (Fe) in greenhouse sand culture was investigated. After establishment, clones were grown for 3 weeks and irrigated with a half-strength Hoagland's solution containing 0, 2, 4, 6, and 8 mg·L-1 Fe in citrate-Fe. Shoot and root responses to Fe were similar for the VAB and FAB biotypes. However, VAB had higher color ratings (darker green leaf color) with Fe treatment level at 4 mg·L-1 than did FAB or CB, which required 6 mg·L-1 Fe for acceptable color. Growth of creeping bentgrass was greater than that of annual bluegrass at every Fe level tested. Shoot dry weights of CB increased significantly with Fe treatment level up to 6 mg·L-1. Shoot dry weight of AB increased up to 4 mg·L-1 Fe and then declined at ≥6 mg·L-1. Root growth of CB increased up to 6 mg·L-1 Fe, but then decreased significantly at 8 mg·L-1 Fe. Root growth of AB increased slightly up to 4 mg·L-1 Fe and then declined at 6 and 8 mg·L-1. Shoot tissue concentrations of Fe were similar for AB and CB at each Fe rate tested except at 8 mg·L-1 Fe, where Fe levels in CB were significantly lower. Based on this work, creeping bentgrass and annual bluegrass respond differently to Fe nutrition, but different biotypes of annual bluegrass appear to respond similarly.

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Seeding of Creeping Bluegrass into Existing Golf Course Putting Greens

HortScience ◽

10.21273/hortsci.40.2.457 ◽

2005 ◽

Vol 40 (2) ◽

pp. 457-459

Author(s):

Eric D. Miltner ◽

Gwen K. Stahnke ◽

Geoffrey J. Rinehart ◽

Paul A. Backman

Keyword(s):

Seedling Establishment ◽

Poa Annua ◽

Golf Course ◽

First Year ◽

Putting Greens ◽

Establishment Success ◽

Annual Bluegrass ◽

Establishment Potential ◽

Second Year ◽

Seedbed Preparation

The recent release of `True-Putt' (previously `DW-184') creeping bluegrass [Poa annua L. f. reptans (Hauskins) T. Koyama] gives turfgrass managers a new option for seeding into annual bluegrass (Poa annua L.) greens. Because little is known about the culture and management of this newly available seeded cultivar, effective methods for seedling establishment into existing turfgrass canopies, both living and dead, were studied. Four surface cultivation treatments were compared for seedbed preparation before seeding into an existing turfgrass canopy. When seeding into dead turf, two passes with vertical mowing units were more effective than hollow-tine cultivation (HTC), solid-tine cultivation (STC), one pass with the vertical mower plus STC, and the uncultivated control during the first year. Differences were not significant during the second year, most likely because of shallower depth of the vertical mower. Plots averaged about 75% cover by 4 weeks after planting during both years, illustrating the rapid establishment potential for `True-Putt'. After seeding into a live turf canopy, seedlings were indistinguishable from the existing turf, making it impossible to evaluate establishment success.

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New Options for Annual Bluegrass Control in Overseeded Bermudagrass Putting Greens

HortScience ◽

10.21273/hortsci.38.6.1232 ◽

2003 ◽

Vol 38 (6) ◽

pp. 1232-1234 ◽

Cited By ~ 5

Author(s):

Joe E. Toler ◽

Lambert B. McCarty ◽

Jason K. Higingbottom

Keyword(s):

Poa Annua ◽

Putting Greens ◽

Golf Greens ◽

Annual Bluegrass ◽

Herbicide Treatments ◽

Poa Trivialis ◽

Putting Green ◽

Weed Diversity ◽

Selective Herbicide

Annual bluegrass (Poa annua L.) continues to be a problem in bermudagrass golf greens overseeded with roughstalk bluegrass (Poa trivialis L. `Sabre) due to weed encroachment from adjacent fairways, lack of selective herbicide options, and weed diversity. A 2-year study was conducted on an overseeded `Tifgreen bermudagrass putting green to evaluate effects of herbicide treatments on overseeding and annual bluegrass control. Excellent annual bluegrass control (≥90%) and acceptable turfgrass cover (§70%) was achieved with oxadiazon at 2.2 kg·ha-1 a.i. applied 60 days before overseeding (DBO). Fenarimol (AS) at 4.1 kg·ha-1 a.i. (30 + 15 DBO) followed by 1.4 kg·ha-1 a.i. 60 days after overseeding (DAO) and dithiopyr at 0.6 kg·ha-1 a.i. (60 DBO + 120 DAO) also provided acceptable results. Dithiopyr at 0.4 kg·ha-1 a.i. (30 DBO + 120 DAO), dithiopyr at 0.3 kg·ha-1 a.i. (30 DBO + 30 + 120 DAO), and fenarimol (G) at 2.0 kg·ha-1 a.i. (45 + 30 DBO) followed by 0.8 kg·ha-1 a.i. 60 DAO provided inconsistent annual bluegrass control (55% to 75% in 1999 and 87% to 95% in 2000), but offered acceptable turfgrass cover (§70%) each year. The remaining treatments were generally ineffective and provided <50% annual bluegrass control one or both years. Oxadiazon applied 60 DBO at 2.2 kg·ha-1 a.i. provides an excellent option for annual bluegrass control in overseeded bermudagrass putting greens.

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