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Nursery Management Magazine




May 1, 2010
A brief report for nurseries which offers ideas on how to overcome some of the recent challenges in the nursery industry. To facilitate that effort, Oregon State University tracked nursery sales and pricing in order to offer a fresh look at what drives sales and how the industry can respond to recent changes.
July 1, 2010
Comprehensive guide on how to control spider mites in the nursery biologically by using predatory mites. Predatory mites are tiny little animals whose appetite for spider mites makes them a great tool for suppressing and managing mite outbreaks.
August 1, 2010
Research was conducted at Oregon State University North Willamette Research and Extension Center with the objective of determining whether the addition of foliar fertilization would benefit a Christmas tree plantation or container-grown conifer operation.
February 1, 2010
Plant trials featuring Arctostaphylos and Grevillea varieties were conducted at Oregon State University North Willamette Research and Extension Center (NWREC). The purpose of the trials was to evaluate the plants performance in the landscape.
December 6, 2011
Researchers evaluated the toxicity of glucolimnathin 1 and its degradation products on several important soilborne pathogens of high-value crops. Pests targeted in the studies included plant-parasitic nematode Meloidogyne hapla, fungus Verticillium dahliae, and oomycete Pythium irregulare.
May 1, 2011
In an attempt to identify Pythium species (common dampening off pathogens) associated with forest nursery soils, field surveys were conducted at three forest nurseries (two in Oregon and one in Washington) in 2008 using three isolation methods.
February 3, 2007
Research was conducted to determine the persistence of Metarhizium anisopliae (F52), measured as infectivity against black vine weevil larvae, in a soilless potting medium at six wholesale nursery locations across the Willamette Valley, Oregon.
March 12, 2007
A report on research conducted to determine the susceptibility of the two primary direct insect pests of hazelnuts in Oregon to three species of entomopathogenic nematodes. Additionally, a small-scale replicated field trial was performed to determine the efficacy of the two most effective nematodes species in the laboratory against both insects in the field.
January 1, 2008
The purpose of this research was to determine the susceptibility of the strawberry crown moth, Synanthedon bibionipennis (Boisduval) (Lepidoptera: Sesiidae) larvae to two species of entomopathogenic nematodes. The entomopathogenic nematodes Steinernema carpocapsae (Weiser) strain Agriotos and Heterorhabditis bacteriophora (Steiner) strain Oswego were evaluated in laboratory soil bioassays and the field.
August 29, 2011
Fumigation treatments (a conventional methyl bromide – chloropicrin application and reduced-rate alternative fumigant treatments) and a nonfumigated treatment were evaluated at forest nurseries in Oregon and Washington for their effects on soil pathogen populations, weeds, and seedling morphology.
November 5, 2010
This study sought to ascertain if there was an association between host plant and species of fungi by using phylogenetic analysis to determine the prevalence of Metarhizium and Beauveria spp. isolated from the rhizosphere of strawberry, blueberry, grape and Christmas tree crops in the Willamette Valley of Oregon.
March 10, 2009
These studies were conducted to determine the compatibility of M. anisopliae (F52) with a wide range of fungicides commonly applied to container-grown ornamentals for the management of soil-borne plant pathogens. In addition, the impact of fungicide application to M. anisopliae population in soilless potting media (bulk and rhizosphere soil) was also determined.
June 1, 2006
The purpose of this study was to determine the persistence, measured as efficacy against BVW larvae, of M. anisopliae in five (coir, fir bark, hemlock bark, peat moss and perlite) common components of soilless potting media.
June 1, 2005
The objective of these studies was to determine the pathogenicity of entomopathogenic fungi against the cabbage maggot, Delia radicum (L.). The use of Metarhizium anisopliae isolate F52 in an integrated management program is discussed.
September 1, 2007
The objectives of this study were to determine the efficacy of a curative drench application of M. anisopliae for controlling black vine weevil (BVW) larval infestations in container-grown nursery plants and the effect of temperature on the rate of fungal growth and speed of kill.
January 1, 2008
Researchers recently developed a mass rearing system for the black vine weevil (Otiorhynchus sulcatus) and strawberry root weevil (Otiorhynchus ovatus) and now are able to conduct controlled experiments to study their biology and to develop chemical and biological management systems.
July 1, 2004
Experiments were performed to determine if 1) O. sulcatus larval survival and development increased with a standard or improved diet and 2) whether O. sulcatus eggs could be stored for up to 4 weeks at 4 °C without significant reductions in larval survival and development.
December 1, 2005
Studies were conducted to determine the efficacy of three species of entomopathogenic nematodes (Heterorhabditis marelatus, Heterorhabditis bacteriophora, and Steinernema riobrave) applied in infected host cadavers or as aqueous applications for black vine weevil larval control.
January 1, 2004
The black vine weevil Otiorhynchus sulcatus (F.) is the primary insect pest of field and container-grown woody ornamentals in the Pacifc Northwest (PNW). These studies were conducted to determine the natural occurrence of soil-borne entomopathogens in PNW nursery soils and determine their virulence to black vine weevil.
January 1, 2006
The purpose of this study was to characterize the behavior of black vine weevil larvae, Otiorhynchus sulcatus (F.), in the presence of two possible control options: the synthetic pyrethroid bifenthrin and the entomopathogenic fungus Metarhizium anisopliae (Metch.) Sorokin.
October 1, 2004
Studies on the biological control of black vine weevil (BVW) in container-grown ornamentals were conducted to determine the persistence and ecology of Metarhizium anisopliae (Metchnikoff) Sorokin incorporated into peat and bark-based potting media with and without a crab meal amendment in container-grown Picea abies ‘Nidiformis.’
February 1, 2012
A report on the influence of irrigation frequency and rate of nitrogen (N) application on uptake of other nutrients in one deciduous and two evergreen cultivars of Rhododendron grown in containers for 1 year. Researchers also evaluated whether nutrient concentrations in different structures and ratios of N to other nutrients in leaves and whole plants could be used to detect the influence of irrigation frequency on the relationship between N and other nutrients.
September 1, 2010
Researchers collected samples of blueberry roots from fields in Australia in an effort to (1) identify the fungi present in roots of field-grown blueberry plants, (2) determine whether the fungi formed mycorrhizae with blueberry plants, and (3) establish whether the fungi preferred specific sources of nitrogen (N) for growth.
April 1, 2010
The specific objectives of the study were to determine whether susceptibility of field-grown pear trees to P. syringae is related to N concentration in stems and is altered by spraying trees with urea or the defoliant CuEDTA at different times in the autumn before and after inoculation with the pathogen.
January 1, 2010
In this study researchers evaluated the chicoric acid concentrations in dried and fresh basil (Ocimum basilicum) products available to consumers and how these concentrations compare to those from E. purpurea plant and products.
February 1, 2011
The objectives of the study were to determine whether N availability alters 1) the uptake of other nutrients; 2) allocation of other nutrients among different plant structures; 3) ratios of N uptake to uptake of other nutrients (N uptake ratios); and 4) nutrient losses during the fall and winter.
April 1, 2008
The purpose of this study was to determine: 1) how rate of N application during the vegetative stage of production influences plant growth; 2) whether plant N content before cold storage influences plant growth and flower development during forcing; and 3) whether urea sprays in the fall increase N storage before cold storage and plant growth and flower development during forcing.
January 1, 2009
This study was conducted to 1) evaluate whether simple linear regression in combination with reflectance sensitivity analysis can be used to determine optimal wavelength (OW) for Chl assessment using reflectance; and 2) evaluate the importance of using OW in the development of Chl-related reflectance indices.
February 1, 2010
The objectives of this study were to determine whether bud necrosis in green ash was associated with tree N status, and whether green ash trees containing the same amount of N from different types of fertilizer exhibited similar amounts of bud necrosis.
April 1, 2010
Using green ash (Fraxinus pennsylvanica) trees as a model for fast-growing shade trees, the objective of this study was to determine whether N application rate and fertilizer type differentially influence cold tolerance of green ash.
March 1, 2007
The information provided by this study will aid in the development of fertilizer management strategies for container nursery production practices that will decrease fertilizer use and production costs, improve plant quality, while minimizing N losses to the environment.
June 1, 2007
Using deciduous and evergreen cultivars of container-grown Rhododendron, the objectives of this study were to determine: (i) whether N application rate during the growing season influenced plant response to foliar urea application in the Autumn; and (ii) whether plant N status in the Winter influenced plant reliance on fertilizer for growth the following Spring.
June 1, 2008
Deciduous and evergreen cultivars of container-grown Rhododendron were used to determine whether spraying plants with urea in the fall altered 1) uptake of nutrients other than N in the year of application and the following growing season; and 2) allocation of nutrients other than N in the year of application and the following growing season.
September 1, 2008
Research was conducted using evergreen and deciduous Rhododendron cultivars. The objectives of this research were to determine whether N-availability in the growing medium alters (A) the rate of uptake of other nutrients; (B) allocation of other nutrients between different plant structures; and (C) plant demand for other nutrients as reflected in ratios of N to other nutrients (N-ratios).
January 1, 2006
Research report detailing a study conducted on the involvement of polyamines (PAs) in the interaction between Pinus sylvestris L. seedlings and an ectomycorrhizal fungus Suillus variegatus (Swatz: Fr.) O. Kunze in an in vitro cultivation system.
January 1, 2006
The purpose of this study was to determine if arbuscular mycorrhizal fungi (AMF) inoculation influences plant development, reproduction (vegetative and floral), and/ or tuber quality in calla lily (Zantedeschia spp. and hybrids).
July 1, 2006
A discussion about mycorrhizae, a natural fungi that can greatly improve plants' nutrient and water uptake. The authors specifically discuss why mycorrhizae are important, whether or not they are needed, necessary materials, and when and how to use mycorrhizae.
March 1, 2007
An examination of the advantages and affects of nitrogen (N) foliar feeding on the quality of nursery plants. Topics include which N formulation is best, fall applications, advantages of fall foliar nitrogen, and spring applications.
January 1, 2005
The intent of the study was to determine whether an EMF inoculum, added to the rooting substrate during cutting propagation, can alter root production by L. fontanesiana, and whether responses to inoculation depend on the EMF isolate used as inoculum.
January 1, 2005
This study investigates the potential role EMF plays in container-grown blueberry production. Specifically, it was determined whether growth and nutrition of highbush blueberry is influenced by inoculation with various EMF isolates, and whether the response to EMF is altered by the type of fertilizer used.
January 1, 2005
The ambitions of the study were to compare the effects of different timings of nitrogen (N) application on leaf and root N uptake, and to determine the distribution of N absorbed by leaves and roots at different times in young Fuji/M.9 apple trees.
January 1, 2005
The intent of this study was to determine the (1) effect of soil versus foliar nitrogen (N) applications during the summer on tree growth, and (2) effect of soil versus foliar N applications during summer on N uptake in the autumn in young apple trees.
January 1, 2005
A report on a survey conducted on commercial nursery plants produced from tissue culture and cuttings to determine when or if ericoid mycorrhizal fungi (EMF) colonize blueberry plants under nursery cultural methods.
January 1, 2003
The objectives of the USDA-ARS affiliated study were to determine whether growth, nutrient use, and storage components of ericaceous plants differ when grown in media amended with varying proportions of sphagnum peat or coir.
January 1, 2003
Research was conducted with the intent of evaluating the effect of different levels of root damage at planting on nitrogen uptake and growth of bench-grafted young apple (Malus domestica Borkh 'Fuji'/M.26) nursery trees.
January 1, 2003
The purpose of this study was to determine which source of nitrogen (N) (i.e. reserves or spring fertilizer applications) has the greater effect on new growth of almond nursery trees. 'Nonpareil' almond (Prunus dulcis (Mill) D. A. Webb) trees on 'Nemaguard' rootstocks were used in the study.
January 1, 2004
The objectives of the study were to 1) determine whether addition of AMF inoculum into the growing medium of harlequin flower alters aspects of flower production, bulb production, and bulb quality, and 2) assess whether other rhizosphere organisms present in the AMF inoculum play a role in plant response to inoculation.
November 1, 2002
In this study, N-urea was used to assess uptake, translocation and distribution of nitrogen (N) from urea after application in the autumn to leaves of 1-year old bench grafted apple (Malus domestica Borkh) nursery trees.
January 1, 2003
A report on research conducted to determine 1) whether the addition of vesicular–arbuscular mycorrhizal fungi (VAMF) inoculum into the rooting substrate during cutting propagation increases rooting of hick’s yew and 2) how the quantity of VAMF inoculum influences the rooting of hick’s yew under nursery production conditions.
June 1, 2001
Field trials were conducted to assess the potential to modify the IAA concentration in roots, root growth responses, and plant survival by root application of plant growth regulators (PGRs) such as IBA, NAA, and ethylene, or alginate, a moisture retention material.