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Impacts of long‐term fertilization and cultivation were evaluated on nematode communities associated with tall fescue turfgrass following 11 years of treatment applications. Fertilizer treatments of biosolid, synthetic, and plant‐based fertilizers and cultivation treatments of 0×, 1×, and 2× aerification passes were applied to randomized and replicated tall fescue plots at the University of Maryland Paint Branch Turfgrass facility in College Park, Maryland. Free‐living and plant‐parasitic nematodes were identified, enumerated, and categorized into functional groups. Nematode count data were compared using generalized linear mixed modeling with negative binomial distribution and two‐way ANOVA was used to compare nematode ecological indices. Biosolid treatments resulted in lower omnivore‐predator densities than plant‐based fertilizer treatments (p ≤ .001) and significantly greater Hoplolaimus densities than plant‐based fertilizer plots (p ≤ .05). Synthetic fertilizer applications resulted in the greatest Eucephalobus (p ≤ .05) and total bacterivore densities (p ≤ .001) of all fertilizer treatments. Plant‐based fertilizer‐treated plots had the largest Maturity Index cp 2‐5 and Structure Index (p ≤ .05). Cultivation of 1× resulted in fewer total bacterivore densities than 2× (p ≤ .01) while omnivore‐predator densities were greater in 1× than 0× (p ≤ .001). Plant health, as measured by NDVI, was lowest in biosolid‐treated turfgrass (p ≤ .05). These findings suggest that long‐term turfgrass management practices can have variable impacts on nematode abundance and community structure in tall fescue and provide insights into ecological impacts of turfgrass management practices. Turfgrass fertilizer applications over 11 years had variable effects on soil nematode abundance and community structure. Biosolid‐based fertilizer applications where Cu, Fe, and Zn concentrations were highest resulted in the highest plant‐parasitic Hoplolaimus abundance and lowest beneficial omnivore‐predator nematode abundance.

Urbanization is rapidly influencing the abundance and diversity of arthropods. Within urban systems, managed turfgrass is a prominent land cover which can support only a limited number of arthropod groups. To allow for more arthropod biodiversity and to support beneficial insects within turfgrass, increasing numbers of land managers are choosing to partially convert turf habitat to wildflower habitat using commercially available seed mixes. However, the population dynamics of arthropod groups in these systems are poorly known, with consequentially little information on best long-term practices for managing wildflower habitats in turfgrass systems. To address this gap, we sampled insects using pan traps in turfgrass systems pre- and post-implementation of wildflower habitats and examined the change in abundance of several insect families and functional guilds. Insect groups had variable responses to wildflower habitat implementation, with some groups such as sweat bees and skipper butterflies showing a decline two years post-implementation. Other groups, such as predatory flies, were relatively more abundant one and two years post-implementation. These variable responses point to the need for more research on the long-term effects of wildflower habitats on beneficial insects in turfgrass habitats.

Methiozolin is an isoxazoline herbicide that selectively controls annual bluegrass in cool-season turf and may control roughstalk bluegrass, another weedy Poa species 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-1 applied four times in fall reduced roughstalk bluegrass cover 85%. This was equivalent to methiozolin at 1000 g ha-1 applied 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. Nomenclature: Amicarbazone; bispyribac-sodium; methiozolin; 5-(2,6-difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)-1; 2-isoxazoline; code names: EK-5229, SJK-03, and MRC-01, prmisulfuron, annual bluegrass, Poa annua L.; roughstalk bluegrass, Poa trivialis L.; creeping bentgrass, Agrostis stolonifera L.

Clover inclusion may increase the sustainability of certain low-maintenance turfgrasses. However, selective weed control within mixed turfgrass–clover swards proves problematic because of clover susceptibility to herbicides. Research was conducted to identify common turf herbicides that are tolerated by three Trifolium species, including white clover, ball clover, and small hop clover, within low-maintenance turfgrass. Leaf and flower density, as well as plant height, were measured 4 wk after treatment as indicators of clover response to 14 herbicides. The three Trifolium spp. were moderately tolerant of bentazon (< 35% decrease in leaf density, height, or flowering). Simazine was well tolerated by white clover (< 5% decrease in all response variables), yet moderate injury to ball clover and small hop clover was observed (> 32% decrease in leaf density and > 27% decrease in flower density). Pronamide was well tolerated by white and ball clovers, with no effect on measured response variables; however, pronamide decreased small hop clover height and flower density (38 and 42%, respectively). Imazethapyr and imazamox were moderately well tolerated by white clover and small hop clover (< 39% decrease by all response variables), yet ball clover may be more susceptible to these herbicides than was anticipated based on previously reported tolerance. The herbicides 2,4-DB, halosulfuron, and metribuzin were well tolerated by white clover, with no effect on measured response variables; however, results suggest ball and small hop clovers were less tolerant. Clopyralid, 2,4-D, glyphosate, imazaquin, metsulfuron-methyl, and nicosulfuron resulted in varying degrees of injury across clover species and response variables, but, in general, these herbicides may not be viable options when attempting to maintain any of the three clover species tested. Further research is needed to quantify long-term effects of herbicide application on sward composition and clover succession. Nomenclature: 2,4-D; 2,4-DB; bentazon; clopyralid; glyphosate; halosulfuron; imazaquin; imazethapyr; imazamox; metribuzin; nicosulfuron; pronamide; simazine; metsulfuron-methyl; ball clover, Trifolium nigrescens Viv., small hop clover, Trifolium dubium Sibth. TRFDU, white clover, Trifolium repens L. TRFRE. La inclusión de Trifolium podría incrementar la sostenibilidad de varios céspedes de bajo mantenimiento. Sin embargo, el control selectivo de malezas en mezclas de céspedes con Trifolium es problemático debido a la susceptibilidad de Trifolium a muchos herbicidas. Se realizó una investigación para identificar herbicidas comunes para céspedes que son tolerados por tres especies de Trifolium, incluyendo Trifolium repens, Trifolium nigrescens, y Trifolium dubium, en céspedes de bajo mantenimiento. La densidad de hojas y flores, al igual que la altura de planta, fueron medidas 4 semanas después del tratamiento, como indicadores de la respuesta de Trifolium a 14 herbicidas. Los tres Trifolium spp. fueron moderadamente tolerantes a bentazon (< 35% de disminución en densidad de hojas, altura, o floración). T. repens también toleró simazine (< 5% disminución en todas las variables de respuesta), aunque se observó un daño moderado en T. nigrescens y T. dubium (> 32% disminución en densidad de hojas y > 27% disminución en densidad de flores). Pronamide fue tolerado por T. repens y T. nigrescens, sin ningún efecto en las variables de respuesta medidas. Sin embargo, pronamide disminuyó la altura y densidad de flores de T. dubium (38 y 42%, respectivamente). Imazethapyr e imazamox fueron moderadamente tolerados por T. repens y T. dubium (< 39% disminución de todas las variables de respuesta), aunque T. nigrescens podría ser más susceptible a estos herbicidas que lo que se anticipó con base en reportes previos de tolerancia. Los herbicidas 2,4-DB, halosulfuron, y metribuzin fueron bien tolerados por T. repens, sin efectos en las variables de respuesta medidas. Sin embargo, los resultados sugieren que T. nigrescens y T. dubium fueron menos tolerantes. Clopyralid, 2,4-D, glyphosate, imazaquin, metsulfuron-methyl, y nicosulfuron resultaron en varios grados de daño entre las especies de Trifolium y las variables de respuesta, pero en general, estos herbicidas no serían opciones viables al tratar de mantener alguna de las especies de Trifolium evaluadas. Investigaciones adicionales son necesarias para cuantificar los efectos a largo plazo de la aplicación de herbicidas en la composición del césped y la sucesión de especies de Trifolium.

The tolerance of bermudagrass and stargrass to the relatively new herbicide, aminocyclopyrachlor (ACP), must be known before it can be recommended for weed control in these forage systems. Field experiments were conducted in 2012 and 2013 in south-central Florida to determine the tolerance of established bermudagrass and stargrass to various rates and combinations of ACP, chlorsulfuron, 2,4-D, triclopyr, and metsulfuron. Overall, bermudagrass and stargrass injury was transient and was minimal by 60 d after treatment (DAT). Similarly, biomass production was negatively affected at 30 DAT when treated with ACP at rates of 70 g ae ha−1 or greater, but was similar to the nontreated control by 60 DAT. Tank-mixing ACP with chlorsulfuron, 2,4-D amine, triclopyr, or metsulfuron did not increase injury compared with ACP alone applied at equivalent rates. Forage nutritive values were unaffected by herbicides. These data suggest that long-term effects of ACP on bermudagrass and stargrass are negligible, and this herbicide could be an important component of weed management programs in these forage systems. Nomenclature: Aminocyclopyrachlor; chlorsulfuron; metsulfuron; triclopyr; bermudagrass, Cynodon dactylon L.; stargrass, Cynodon nlemfuensis Vanderyst. La tolerancia del pasto bermuda y el pasto estrella al herbicida relativamente nuevo, aminocyclopyrachlor (ACP), debe ser conocida antes de poder recomendarlo para el control de malezas en sistemas de forrajes. En 2012 y 2013, se realizaron experimentos de campo en el sur-centro de Florida para determinar la tolerancia de pastizales establecidos de bermuda y estrella a varias dosis y combinaciones de ACP, chlorsulfuron, 2,4-D, triclopyr, y metsulfuron. En general, el daño a los pastos bermuda y estrella fueron transitorios y mínimos a 60 d después del tratamiento (DAT). Similarmente, la producción de biomasa fue negativamente afectada a 30 DAT cuando se trató con ACP a dosis de 70 g ae ha−1 o mayores, pero fue similar al testigo sin tratamiento a 60 DAT. Las mezclas en tanque de ACP con chlorsulfuron, 2,4-D amine, triclopyr, o metsulfuron no aumentaron el daño al compararse con ACP aplicado solo a dosis equivalentes. El valor nutritivo del forraje no fue afectado por los herbicidas. Estos datos sugieren que los efectos a largo plazo de ACP sobre los pastos bermuda y estrella son mínimos, y este herbicida podría ser un componente importante de los programas de manejo de malezas en estos sistemas de forrajes.

Turfgrass is a highly managed ecosystem subject to frequent fertilization, mowing, irrigation, and application of pesticides. Turf management practices may create a perturbed environment for ammonia oxidizers, a key microbial group responsible for nitrification. To elucidate the long-term effects of turf management on these bacteria, we assessed the composition of betaproteobacterial ammonia oxidizers in a chronosequence of turfgrass systems (i. e., 1, 6, 23, and 95 years old) and the adjacent native pines by using both 16S rRNA and amo A gene fragments specific to ammonia oxidizers. Based on the Shannon-Wiener diversity index of denaturing gradient gel electrophoresis patterns and the rarefaction curves of amoA clones, turf management did not change the relative diversity and richness of ammonia oxidizers in turf soils as compared to native pine soils. Ammonia oxidizers in turfgrass systems comprised a suite of phylogenetic clusters common to other terrestrial ecosystems. Nitrosospira clusters 0, 2, 3, and 4; Nitrosospira sp. Nsp65-like sequences; and Nitrosomonas clusters 6 and 7 were detected in the turfgrass chronosequence with Nitrosospira clusters 3 and 4 being dominant. However, both turf age and land change (pine to turf) effected minor changes in ammonia oxidizer composition. Nitrosospira cluster 0 was observed only in older turfgrass systems (i.e., 23 and 95 years old); fine-scale differences within Nitrosospira cluster 3 were seen between native pines and turf. Further investigations are needed to elucidate the ecological implications of the compositional differences.

HENDERSON, Nev.--(BUSINESS WIRE)--Aug. 13, 1999--The senior executive team at AgriBioTech Inc. (\"ABT\" or the \"company\") (Nasdaq:ABTX) met with sell-side analysts that cover ABT this week to review and update them on the company's business and business plan, to announce that it has received proposals for and is working on completing new, long-term debt financing that is expected to provide the company with the working capital it needs to carry out its long- term business plan, and presented data that supports the company's expectations of profitability in fiscal year 2000 (FY2000). ABT expects to finalize one of these options within 60 days. Combined with profitable operations, new long-term debt financing will solve the company's financing needs because it will allow ABT to replace short-term debt that was used to acquire some companies during the previous acquisition program with long-term debt. The company's long-term business plan is to use the large, vertically integrated forage and turfgrass seed platform it has built to develop and market value-added, superior-performing, high-margin proprietary seeds in a sector of the seed industry that had, prior to ABT, been highly fragmented and lacked aggressive and sustained investment in research and development (R&D) of new varieties.

U.S. FOODSERVICE PARENT'S PROFITS IN QUESTION: The Dutch-based supermarket giant Ahold, which operates U.S. Foodservice, warned Monday that profits last year may have been overstated by more than $500 million. Ahold, audited by Deloitte & Touche, said it was investigating accounting \"irregularities\" at its U.S. Foodservice arm and also the legality of transactions at its Disco operation in Argentina. Fax news to Denyse Clark at 329-4021; mail it to The Herald, Business News, P.O. Box 11701, Rock Hill, SC 29731; call 329-4069; or e-mail dclark@heraldonline.com.