bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetically Modified, Insect Resistant Maize: Implications for Management of Ear and Stalk Diseases
Authors: Munkvold G. P. , Hellmich R. L.
Published: May 2008

Because the fungi that produce mycotoxins in maize are frequently associated with insect damage, insect control has the potential to reduce mycotoxin concentrations in grain. Our research indicates that Bt transformation of maize hybrids enhances the safety of grain for livestock and human food products by reducing the plants' vulnerability to mycotoxin-producing Fusarium fungi.

Accepted for publication 5 September 2000. Published 12 September 2000.
The Christmas Tree: Traditions, Production, and Diseases
Authors: Chastagner Gary A. , Benson D. Michael
Published: May 2008

This article takes a historical look at the Christmas tree industry and discuss three diseases limiting growers' ability to meet the demand for noble and Fraser fir in North America: Phytophthora root rot and stem canker, current season needle necrosis (CSNN), and interior needle blight.

Accepted for publication 14 September 2000. Published 13 October 2000.
Antibiotic Use for Plant Disease Management in the United States
Authors: McManus Patricia S. , Stockwell Virginia O.
Published: May 2008

Streptomycin and oxytetracycline have been used on crop plants for 45 years and 25 years, respectively, without reports of adverse effects on humans. Their efficacy for control of plant diseases has been diminished in some regions due to the emergence of resistant pathogens. However, until effective and economic alternatives become available, antibiotics will remain important in the management of devastating plant diseases.

Accepted for publication 19 March 2001. Published 27 March 2001.
Efficacy of Kaolin-Based Particle Films to Control Apple Diseases
Authors: Glenn D. Michael , van der Zwet Tom , Puterka Gary , Gundrum Patricia , Brown Eric
Published: May 2008

Studies were conducted from 1997 to 1999 to evaluate the effect of processed kaolin-based particle film applications on the incidence and severity of apple (Malus domestica Borkh.) diseases. Greenhouse and field studies demonstrated that pre-emptive application of hydrophobic and hydrophilic particles reduced the incidence of fire blight (Erwinia amylovora (Burrill) Winslow et al.) in blossoms and injured shoots. Hydrophobic and hydrophilic particles suppressed sooty blotch (Gloeodes pomigena (Schwein.)) and flyspeck (Schizothyrium pomi (Mont. & Fr.) Arx: anamorph Zygophiala jamaicensis Mason) to levels equivalent to conventional fungicides. In field studies, apple scab (Venturia inaequalis (Cooke) Wint.: anamorph Spilocaea pomi Fr.) was not suppressed by hydrophilic particles. Hydrophilic particles did not interfere with the action of conventional fungicides or the activity of calcium hydroxide to suppress apple scab. Hydrophilic particles did reduce powdery mildew (Podosphaera leucotricha (Ell. & Ev.) E.S. Salmon (anamorph Oidium farinosum Cooke)) russetting on fruit, but leaf infection was extensive.

Accepted for publication 27 July 2001. Published 23 August 2001.
White Pine Blister Rust
Authors: Maloy Otis C.
Published: May 2008

White pine blister rust is probably the most destructive disease of five-needle (white) pines in North America. The rust fungus cannot spread from pine to pine but requires an alternate host, Ribes species, to complete the disease cycle. Several management tools might enable the reestablishment of western white pine stands.

Accepted for publication 20 September 2001. Published 24 September 2001.
Susceptibility of Intermountain Douglas-Fir to Rhabdocline Needle Cast When Grown in the Pacific Northwest
Authors: Chastagner Gary A.
Published: May 2008

Douglas-fir are traditionally grown as Christmas trees in the Pacific Northwest (PNW). Intermountain (IM) provenances of Douglas-fir are less likely to be injured after harvest by exposure to subfreezing temperatures than the coastal provenances. However, planting IM Douglas-fir in the coastal areas of the PNW is currently not recommended because of their high susceptibility to Rhabdocline needle cast. During a three-year period, needle cast severity was rated (0 to 100 scale) on trees in a replicated planting of IM Douglas-fir near Puyallup, WA. In 1997, needle cast ratings ranged from 0.8 to 70. Trees from the Cibola National Forest (NF) had significantly higher needle cast ratings (70.0) than trees from Carson NF (17.3), Coconino NF (15.7), Rio Grande NF (5.0), and Upper Clearwater, ID (0.8). Trees from the Apache NF (51.4), San Isabel NF (32.3), two collections representing the Lincoln NF (25.4-30.2), and the Santa Fe NF (21.3) had intermediate levels of needle cast. This study shows that certain sources of IM Douglas-fir can be grown in the PNW with minimal Rhabdocline needle cast problems. Applications of chlorothalonil also provided effective needle cast control on all but the most susceptible provenance.

Accepted for publication 15 October 2001. Published 29 October 2001.
Applications of Mixtures of Copper Fungicides and Chlorothalonil for Management of Peanut Leaf Spot Diseases
Authors: Culbreath A. K. , Brenneman T. B. , Kemerait R. C.
Published: May 2008

Management of early leaf spot (Cercospora arachidicola) and late leaf spot (Cercosporidium personatum) of peanut (Arachis hypogaea) in the southeastern U.S. is dependent upon multiple applications of foliar fungicides. Field experiments were conducted from 1997 to 2000 to compare the efficacy of mixtures of copper hydroxide or copper oxychloride and reduced rates of chlorothalonil with that of full rates of chlorothalonil alone or chlorothalonil + propiconazole. In all tests, rates per ha of 0.70 kg of chlorothalonil + 0.70 kg of copper oxychloride or higher provided leaf spot control that was similar (P > 0.05) to that achieved with standard rates of chlorothalonil (0.84 kg/ha) + propiconazole (0.063 kg/ha). Application of chlorothalonil at 0.56 kg/ha + copper oxychloride at 0.56 kg/ha controlled leaf spot as well as (P > 0.05) chlorothalonil alone at 1.26 kg/ha in five of six tests in which that treatment was evaluated. In three of four tests in 1998 and 1999, application of chlorothalonil at 0.63 kg/ha + copper hydroxide at 0.63 kg/ha controlled leaf spot as well as chlorothalonil alone at 1.26 kg/ha. In both tests in 2000, application of chlorothalonil at 0.84 kg/ha + copper hydroxide at 0.63 kg/ha controlled leaf spot as well as chlorothalonil alone at 1.26 kg/ha. There were no consistent yield differences among the chlorothalonil, chlorothalonil + propiconazole, or chlorothalonil + copper treatments.

Accepted for publication 8 November 2001. Published 16 November 2001.
Seed Borne Late Blight of Potato
Authors: Powelson Mary L. , Ludy Robin , Heather Heather , Inglis Debra A. , Gundersen Babette , Derie Mike
Published: May 2008

Planting of potato seed pieces infected with Phytophthora infestans can lead to the introduction of late blight within a planting. When infected seed pieces are planted, there are three resulting scenarios: (i) a healthy plant emerges, (ii) no plant emerges because of the rapid decay of the seed piece, or (iii) a symptomatic plant emerges. A major factor favoring stand establishment and seed transmission is the severity of seed piece infection. When infection is severe, stand is compromised and transmission rate is low. When infection is mild, the plant emerges before the seed piece decays and, in some instances, the pathogen makes its way from the seed piece to the plant where a stem lesion is formed. Diseased seed tubers are the principle source of late blight inoculum for infection of healthy seed pieces. Treatment of infected or blighted seed tubers with a seed dressing with activity against P. infestans is not a viable tactic because the products are ineffective against established infections. Conversely, treatment of healthy seed pieces provides a high level of protection against late blight spores that are spread during the seed handling and planting operations. Optimum effectiveness is achieved when products are applied immediately following cutting, as none are effective against established infections. Seed treatment reduces the risk of seed transmission of late blight and enhances stand establishment and plant vigor. This tactic should be an important component of an integrated late blight management program.

Accepted for publication 16 January 2002. Published 29 January 2002.
Bacterial Crown Rot of Lisianthus Caused by Burkholderia gladioli
Authors: Seijo Teresa E. , Biologist Senior , McGovern Robert J. , Dickstein Ellen R. , Harbaugh Brent K.
Published: May 2008

This is the first report of a bacterial pathogen of lisianthus. The bacterium can be seed-borne and causes a rot of the tap root, crown, and stem, leading to death of plants ranging in age from small seedlings to mature flowering plants.

Accepted for publication 7 May 2002. Published 20 May 2002.
First Report of Southern Wilt Caused by Ralstonia solanacearum on Geranium in Florida
Authors: Pradhanang Prakash M. , Momol M. Timur , Dankers Hank , Momol Esen A. , Jones Jeffrey B.
Published: May 2008

To our knowledge, this is the first report of R. solanacearum causing Southern wilt in geranium in Florida. The pathogen in this case was biovar 1, which is commonly found in the southern United States and South America.

Accepted for publication 7 June 2002. Published 11 June 2002.
Management of the Peanut Root-knot Nematode, Meloidogyne arenaria, with Host Resistance
Authors: Starr J. L. , Morgan E. R. , Simpson C. E.
Published: May 2008

Management of the common peanut root-knot nematode has traditionally relied on treatment of infested fields with nematicides, as well as rotations with other crops. The availability of nematod-eresistant cultivars gives growers another option and will reduce the growers reliance on nematicides. The nematode-resistant peanut cultivars COAN and NemaTAM can be grown in nematode infested fields without having to rely on nematicide applications to achieve the genetic yield potential of the crop.

Accepted for publication 28 October 2002. Published 21 November 2002.
First Report of Powdery Mildew of Mahonia aquifolium Caused by Microsphaera berberidis (Erysiphe berberidis) in North America
Authors: Glawe Dean A.
Published: May 2008

Mahonia aquifolium is a widely-grown plant in the coastal Pacific Northwest. This report documents for the first time a powdery mildew on M. aquifolium in North America caused by a fungus fitting the description of Microsphaera berberidis.

Accepted for publication 14 January 2003. Published 6 February 2003.
Temperature Declines During Storms and Irrigation May Contribute to Fire Blight Infection of Pear Fruit
Authors: Rosenberger David A. , VanCamp Keri L.
Published: May 2008

During summer of 2002, fire blight caused by Erwinia amylovora appeared in immature pears (Pyrus communis) in five Ulster County pear orchards in southeastern New York State. Foliar symptoms of fire blight were absent or infrequent in many trees that had infected fruit, suggesting that fruit infections occurred after shoots had stopped growing and were no longer susceptible to infection. In one orchard where overhead irrigation was initiated on 23 July when air temperatures were 96°F, incidence of fruit infection in September ranged from 10 to 76% with a mean of 36% of all fruit showing fire blight symptoms. Laboratory experiments showed that non-wounded fruit preheated to 95°F and then submerged in inoculum suspensions at 70°F or 40°F developed fire blight infections whereas similar fruit preheated at 70°F and immersed in 70°F-inoculum did not develop infections. Overhead irrigation initiated during the heat of the day can disperse inoculum at the same time that rapid cooling from irrigation water may cause E. amylovora to be drawn into immature pear fruit. The same combination of water-disseminated inoculum and rapid cooling can occur during summer thunderstorms, and storm events may explain the unusual incidence of fire blight on immature pears that was observed in 2002.

Accepted for publication 29 January 2003. Published 10 March 2003.
Toxicity Responses of Herbaceous and Woody Ornamental Plants to Chlorine and Hydrogen Dioxides
Authors: Copes W. E. , Chastagner G. A. , Hummel R. L.
Published: May 2008

Regular and excessive rates of chlorine dioxide (ClO2) and hydrogen dioxide (H2O2) were sprayed five times at 3-day intervals on eight bedding plant and nine shrub species to determine if plant damage would result. Marketability was judged to be reduced if ≥4% surface area of leaves and/or flowers were adversely affected. Rates of 5 and 50 ppm ClO2 and 900 and 2700 ppm H2O2 did not damage most plants tested and will likely control most common pathogen propagules. Rates of 100 ppm ClO2 and 5400 ppm H2O2 did not damage most plants tested if sprayed less than four consecutive times and should control some of the more chemical-tolerant pathogens.

Accepted for publication 11 February 2003. Published 11 March 2003.
Detecting Orobanche minor Seeds in Soil Using PCR
Authors: Rehms Lisa , Osterbauer Nancy K.
Published: May 2008

The federally regulated noxious weed small broomrape (Orobanche minor Smith) is a parasite of several plant species including alfalfa (Medicago sativa L.) and red and white clover (Trifolium pratense L. and T. repens L., respectively) (4). Because of its seed size (200 to 300 mm), it is difficult to detect in harvested clover seed and in soil (3). Recently, we reported a polymerase chain reaction (PCR) assay that can detect small broomrape seed in clover seed (2). This paper reports the testing of this assay for its ability to detect small broomrape in soil.

Accepted for publication 10 June 2003. Published 1 July 2003.
Gray Kernel Disease of Macadamia Nut: Are Bacteria Involved?
Authors: Kaneshiro Wendy S. , Cavaletto Catherine G. , Tang C. S. , Alvarez Anne M.
Published: May 2008

These data point to but do not prove a bacterial etiology for gray kernel disease, and implicate Enterobacter cloacae as one of the causal agents. Other bacteria also may be involved.

Accepted for publication 11 July 2003. Published 25 August 2003.
Proposed Strategies for Begomovirus Disease Management in Tomato in Trinidad
Authors: Rampersad S. N.
Published: May 2008

Geminiviruses represent one of the major groups of phytopathogens of many economically important crops worldwide. In Trinidad, Potato yellow mosaic virus-Trinidad isolate (PYMV-TT) has been implicated as the causal agent of disease epidemics in tomato since the late 1980s. Since its detection there has been an increase both in disease incidence and in geographical distribution among commercial tomato production systems. Current strategies used to control infection have proven to be inadequate at suppressing the disease because such measures are not coordinated, integrated, or regulated. On-going research has identified several epidemic-associated factors which may be involved in PYMV-TT disease spread and persistence. Several management schemes are now recommended as part of a complementary and multi-dimensional system to delay PYMV-TT infection in tomato.

Accepted for publication 28 August 2003. Published 6 October 2003.
First Report of Powdery Mildew of Convolvulus arvensis (Field Bindweed) Caused by Erysiphe convolvuli var. convolvuli in North America
Authors: Glawe Dean A. , Windom Gwenyth E. , Grove Gary G. , Falacy Jennifer S.
Published: May 2008

Field bindweed (Convolvulus arvensis L.) is widespread in the Pacific Northwest where it is considered a noxious weed. During 2002, collections of a powdery mildew fungus attacking C. arvensis were made from Pierce, Spokane, Whitman, and Yakima counties, WA. Based on morphological features we determined the fungus to be Erysiphe convolvuli.

Accepted for publication 22 September 2003. Published 21 October 2003.
First Report of Tomato spotted wilt virus in Hosta in Florida
Authors: Momol M. Timur , Dankers Hank , Adkins Scott
Published: May 2008

In spring 2003, symptoms similar to thrips-vectored spotted wilt disease caused by Tomato spotted wilt virus (TSWV) were observed on outdoor-grown hosta in Florida. Symptoms observed included leaf necrosis and stunting, chlorotic and necrotic spotting, and distinctive ring patterns. This is the first report of TSWV on hosta in Florida.

Accepted for publication 29 September 2003. Published 24 October 2003.
Risk Assessment: Concepts, Development, and Future Opportunities
Authors: Yang X. B.
Published: May 2008

Farming is a risky business. Among the many risk factors, plant disease is an important one due to its close relation to climate and yield. Understanding and assessing disease risk reduce the uncertainties and, therefore, are critical to effective management of plant diseases and, ultimately, to the success of the particular farming venture. Part of the proceedings of “Managing Risk to Minimize Crop Loss,” a symposium organized by the Plant Disease Losses and Regulatory Committees of APS.

Accepted for publication 27 March 2003. Published 13 November 2003.
The Maximum Pest Limit Concept Explained
Authors: Hughes Gareth
Published: May 2008

The maximum pest limit (MPL) concept was developed as a practical method of implementing quarantine security measures against the import of invasive pest species of plants. The MPL itself is simply a threshold upper limit, above which the pest species in question is deemed capable of establishing a population if imported in a consignment of fruit or vegetables. This limit depends on various biological and ecological characteristics of the pest species in question. Important aspects of implementation relate to how treatment and sampling may be combined to reduce the probability that the MPL will be exceeded. If a specified level of treatment efficacy is required (for example, probit nine level), then choice of an appropriate sample size becomes the main problem for regulatory authorities seeking to maintain quarantine security.

Accepted for publication 16 December 2002. Published 13 November 2003.
Bayesian Approaches to Plant Disease Forecasting
Authors: Yuen Jonathan
Published: May 2008

Prediction of disease occurrence is a well known historical theme, and has begun to receive new interest due to internet-based prediction systems. The evaluation of these systems in a quantitative manner is an important step if they are to be used in modern agricultural production. Bayes's theorem is one way in which the performance of such predictors can be studied. In this way, the conditional probability of pest occurrence after a positive or negative prediction can be compared with the unconditional probability of pest occurrence. Both the specificity and the sensitivity of the predictive system are needed, along with the unconditional probability of pest occurrence, in order to make a Bayesian analysis. If there is little information on the prior probability of disease, most predictors will be useful, but for extremely common or extremely rare diseases, a Bayesian analysis indicates that a system predicting disease occurrence or non-occurrence will have limited usefulness.

Accepted for publication 29 January 2002. Published 13 November 2003.
First Report of Powdery Mildew of Ligustrum japonicum (Japanese Privet) Caused by Microsphaera syringae (Erysiphe syringae) in North America
Authors: Falacy Jennifer S. , Glawe Dean A.
Published: May 2008

Powdery mildew was collected from Japanese privet (Ligustrum japonicum Thunb.) in Seattle, King County, WA. The authors determined the causal agent to be Microsphaera syringae (Schw.) Magn. This report documents for the first time the occurrence of M. syringae on L. japonicum in North America, and presents information on the taxonomy and identification of this fungus.

Accepted for publication 6 November 2003. Published 10 December 2003.
First Report of Powdery Mildew of Hypericum perforatum (St. John's-wort) Caused by an Anamorphic Microsphaera Species in the Pacific Northwest
Authors: Glawe Dean A.
Published: May 2008

St. John's-wort has been valued as a medicinal herb for centuries. During the 2002 growing season a specimen plant with powdery mildew symptoms was observed in a demonstration garden in Kenmore, King County, WA. This report provides information on symptoms of the disease, morphological features useful in characterizing the causal agent, and taxonomic aspects of the fungus.

Accepted for publication 30 June 2004. Published 07 July 2004.
Canna yellow mottle virus Detected in Canna in Florida
Authors: Momol M. Timur , Lockhart Benham E. L. , Dankers Hank , Adkins Scott
Published: May 2008

Cannas are herbaceous flowering plants native to the tropics and subtropics and widely cultivated as ornamentals in Florida. Canna yellow mottle virus (CaYMV), previously reported in Japan and Minnesota, is now also present in Florida, based on symptoms, microscopy, PCR, and sequence analysis. There is no known vector for this virus. Canna yellow mottle disease can be an economically important disease constraint on the production of cannas in Florida.

Accepted for publication 14 July 2004. Published 9 August 2004.
Sensitivity of Pseudoperonospora humuli (the Causal Agent of Hop Downy Mildew) from Oregon, Idaho, and Washington to Fosetyl-Al (Aliette)
Authors: Nelson Mark E. , Eastwell Kenneth C. , Grove Gary G. , Barbour James D. , Ocamb Cynthia M. , Alldredge J. Richard
Published: May 2008

Failures of fosetyl-Al (Aliette) to control hop (Humulus lupulus) downy mildew, caused by Pseudoperonospora humuli, have recently occurred in northern Idaho and Oregon. To determine if resistance of the pathogen to the fungicide has developed, leaf disk assays were conducted to compare sensitivity of P. humuli isolates from the different U.S. hop-growing regions to isolates from a research yard where exposure to fosetyl-Al had not occurred for at least 10 years. Dose response curves of transformed data were linear. The fosetyl-Al concentration effective against 50% of the P. humuli isolates (ED50) from each location was estimated from the linearized data. The ED50 values indicate that fosetyl-Al was about one-third as effective against P. humuli isolates from commercial hop yards in northern Idaho and Oregon and about one-half as effective against isolates from southern Idaho compared to isolates from the research yard. Commercial yards in Washington were similar to the research yard.

Accepted for publication 3 August 2004. Published 11 August 2004.
Managing Resistance of Venturia inaequalis to the Strobilurin Fungicides
Authors: Turechek William W. , Köller Wolfram
Published: May 2008

Over the past thirty years, fungicide resistance has been cited as the cause of large-scale crop losses due to apple scab in a number of commercial orchards in the Northeast. The strobilurins represent the most recent class of fungicides for which the threat of resistance exists. In this article we examine the use of strobilurin fungicides at their highest and lowest labeled rates and as a mixture of the lowest labeled rate with a protectant fungicide in commercial spray programs for efficacy against apple scab as well as their utility in a resistance management program. Our results suggest that anti-resistance properties of high strobilurin rates are superior to low rates and low rate mixtures with a protectant fungicide.

Accepted for publication 26 August 2004. Published 8 September 2004.
Methyl Bromide Provides Phytosanitary Security: A Review and Case Study for Senegalese Asparagus
Authors: Davis Erica E. , Venette Robert C.
Published: May 2008

The authors describe how the USDA-APHIS currently uses methyl bromide for imported asparagus, and explore whether methyl bromide treatment schedules might be adequate to control pests of asparagus from Senegal without adversely affecting the quality of the produce.

Accepted for publication 21 October 2004. Published 22 November 2004.
Resistance to Azoxystrobin in the Gummy Stem Blight Pathogen Documented in Georgia
Authors: Stevenson Katherine L. , Langston David B. , Seebold Kenneth W.
Published: May 2008

Gummy stem blight, caused by the fungus Didymella bryoniae, is the most destructive disease of watermelon in Georgia and in many other watermelon producing areas of the U.S. The QoI fungicide azoxystrobin has been used for gummy stem blight control in Georgia since 1998. As early as 1999, reduced control of gummy stem blight with azoxystrobin was noted in several research sites and commercial fields of cucumber and watermelon in Georgia. Isolates from several of these fields were later confirmed to be resistant to azoxystrobin. To determine how widespread the resistance problem was in Georgia, extensive surveys of watermelon and muskmelon fields and transplant houses were conducted in 2001 and 2002 to determine the frequency of azoxystrobin-resistant isolates in populations of D. bryoniae. Of the 272 isolates collected in 2001, 247 (91%) were resistant to azoxystrobin. In 2002, 82% of the 170 isolates collected were resistant to azoxystrobin, and of the 40 isolates collected from watermelon transplants, all but one were resistant to azoxystrobin, suggesting that resistant isolates in the field may have originated from seed or transplants. Georgia melon growers are now advised to use alternative fungicides that are chemically unrelated to the QoIs for gummy stem blight control.

Accepted for publication 2 November 2004. Published 7 December 2004.
First Report of Powdery Mildew on Potato Caused by Leveillula taurica in North America
Authors: Glawe Dean A. , du Toit Lindsey J. , Pelter Gary Q.
Published: May 2008

In August 2004, examination of powdery mildew-infected ‘Russet Burbank’ potato leaves from a furrow-irrigated field in Grant Co., WA, revealed two powdery mildew fungi, one referable to Erysiphe orontii and the other to Leveillula taurica (Lév.) G. Arnaud. Discovery of the two species sporulating together on diseased leaves is consistent with an observation made in the Middle East. This report documents, for the first time, L. taurica on potato in N. America and provides information on distinguishing it from E. orontii.

Accepted for publication 9 December 2004. Published 14 December 2004.
Ascospore Release of Togninia minima, Cause of Esca and Grapevine Decline in California
Authors: Rooney-Latham Suzanne , Eskalen A. , Gubler W. D.
Published: May 2008

Esca and grapevine decline are important diseases affecting both young and mature grapevines worldwide. In California, these diseases are caused primarily by the fungal pathogens Phaeomoniella chlamydospora and Phaeoacremonium aleophilum. Perithecia of Togninia minima, the newly-described teleomorph of Phaeoacremonium aleophilum, were produced by mating different strains in culture. Using a video camera, the process of emerging asci and release of ascospores from perithecia was filmed and presented herein for review. Furthermore, naturally occurring perithecia were discovered in infected California vineyards. These studies provide video documentation of the method of ascospore release of Togninia minima and suggest the importance of ascospore release in the disease cycle of esca in California vineyards.

Accepted for publication 7 December 2004. Published 9 February 2005.
Abnormal Leaf Development on White Oaks Linked to Drift of Chloroacetamide Herbicides
Authors: Samtani Jayesh B. , Masiunas John B. , Appleby James E.
Published: May 2008

In the last few decades, white oak in the north central region have developed malformed spring leaves called “leaf tatters.” Symptoms begin with the death of interveinal leaf tissues, eventually leaving only the main leaf veins with little interveinal tissues present. Winter injury, frost, insect attack, and herbicide drift were all thought to be possible causes of leaf tatters. This study indicates that drift of chloroacetamide herbicides from applications onto corn and soybean fields is a possible cause of the leaf tatters syndrome.

Accepted for publication 14 February 2005. Published 21 February 2005.
Asian Soybean Rust Caused by Phakopsora pachyrhizi on Soybean and Kudzu in Florida
Authors: Harmon Philip F. , Momol M. Timur , Marois J. J. , Dankers Hank , Harmon Carrie L.
Published: May 2008

Asian soybean rust caused by Phakopsora pachyrhizi was found on soybean and kudzu in Florida in November of 2004. The initial diagnosis of soybean rust was based on observations of symptoms and urediniospores. The two species of Phakopsora that cause rust diseases on soybean, P. pachyrhizi and P. meibomiae, cannot be differentiated with light microscopy. A rapid DNA extraction and PCR amplification protocol discriminated between the two species. The sequence of the amplified DNA product confirmed this first report of P. pachyrhizi in Florida.

Accepted for publication 9 May 2005. Published 13 June 2005.
Expansion of the Host Range of Impatiens necrotic spot virus to Peppers
Authors: Naidu Rayapati A. , Deom Carl M. , Sherwood John L.
Published: May 2008

This study reports the occurrence of Impatiens necrotic spot virus (INSV) on pepper under greenhouse conditions. In recent years, INSV has been detected in crops like peanut, tobacco, and potato as well as several weed species. Because INSV is vectored by western flower thrips and tobacco thrips, its expanding host range could make it an economically important problem in agricultural and horticultural crops in the U.S.

Accepted for publication 11 July 2005. Published 27 July 2005.
Phytophthora hibernalis: A New Pathogen on Rhododendron and Evidence of Cross Amplification with Two PCR Detection Assays for Phytophthora ramorum
Authors: Blomquist Cheryl , Osterbauer Nancy , Reeser Paul
Published: May 2008

This study completes Koch's postulates for P. hibernalis on rhododendron. P. hibernalis has previously been described as causing brown rot of citrus. This report expands the pathogen's known natural host range. P. hibernalis does not appear to be widespread in the California and Oregon nursery industries, but was recovered in both states for three consecutive years.

Accepted for publication 8 July 2005. Published 28 July 2005.
Rhabdocline Needlecast Increases Needle Loss of Douglas-fir Christmas Trees
Authors: Bates Ricky M.
Published: May 2008

Little is known about the effect of Rhabdocline needlecast on needle retention characteristics of Douglas-fir. This report describes a needle retention comparison of healthy Douglas-fir branches with symptomless diseased branches.

Accepted for publication 13 September 2005. Published 16 September 2005.
First Report of Powdery Mildew on Corylus avellana caused by Phyllactinia guttata in Washington State
Authors: Hartney Sierra , Glawe Dean A. , Dugan Frank , Ammirati Joseph
Published: May 2008

Contorted hazelnut is an ornamental tree introduced to North America from Europe. In the fall of 2004 and 2005, powdery mildew caused by Phyllactinia guttata (Wallr.:Fr.) Lév. was observed on contorted hazelnut (‘contorta’) located on the campus of Washington State University, Pullman, and on several C. avellana trees (unknown cultivar) on the campus of the University of Washington, Seattle. This report documents for the first time the occurrence of P. guttata on C. avellana in both eastern and western Washington.

Accepted for publication 18 October 2005. Published 21 November 2005.
Susceptibility of Perennial Small Grains to Soilborne wheat mosaic virus and Wheat spindle streak mosaic virus
Authors: Cadle-Davidson L. , Bergstrom G. C. , Cox T. S.
Published: May 2008

Perennial small grains offer the potential for sustainable production of forage and grain on marginal and erodable lands. The authors' results suggest that perennial small grains are at risk for infection by Soilborne wheat mosaic virus (SBWMV) and Wheat spindle streak mosaic virus (WSSMV) and that resistant cultivars may be needed for management of these diseases. Ideally, breeders should screen perennial small grain lines for resistance to soilborne viruses in the early stages of selection.

Accepted for publication 27 October 2005. Published 30 November 2005.
Panama Disease: An Old Nemesis Rears Its Ugly Head: Part 1. The Beginnings of the Banana Export Trades
Authors: Ploetz Randy C.
Published: May 2008

This review summarizes how and where the banana export trades began, the early history of Panama disease, and the important effect that the disease had on the development of this industry. This is a story of political and social upheaval, and of the first large agriculture ventures in the tropics. It focuses on the trades in the Americas before they converted to the resistant Cavendish cultivars.

Accepted for publication 17 October 2005. Published 21 December 2005.
First Report of Powdery Mildew on Caragana arborescens in Minnesota and North Dakota Caused by Microsphaera (Erysiphe) palczewskii
Authors: Glawe Dean A. , Stack Robert W. , Walla James A.
Published: May 2008

In North Dakota and Minnesota, the authors encountered a powdery mildew disease of Caragana arborescens Lam. (Siberian pea tree) previously unreported from these states. The causal agent was determined to be Microsphaera palczewskii Jacz. This report documents for the first time the presence of M. palczewskii in North America east of the Rocky Mountains and includes information on the morphology, classification, and distribution of this species.

Accepted for publication 4 January 2006. Published 17 January 2006.
Identifying and Characterizing Summer Diseases on ‘Babygold’ Peach in South Carolina
Authors: Schnabel Guido , Chai Wenxuan , Cox Kerik D.
Published: May 2008

Summer diseases can cause significant yield losses in processing peach varieties, such as the ‘Babygold’ lines. In this study we identified and characterized the pathogens responsible for disease outbreaks in two orchards (PH and JC) located in the northern ‘Piedmont’ area of South Carolina. Three pathogens, Geotrichum candidum, Colletotrichum acutatum, and Botryosphaeria dothidea, the causal agents of sour rot, anthracnose, and Botryosphaeria fruit rot disease respectively, were identified on fruit from orchard PH using symptomology, culture and spore morphology, and ribosomal DNA analysis. G. candidum and C. acutatum were also isolated from symptomatic fruit from orchard JC. The QoI fungicide azoxystrobin and a mixture of pyraclostrobin and boscalid were evaluated for their in vitro efficacy against five isolates of each of the three pathogens to investigate their possible usefulness in designing management strategies. Azoxystrobin inhibited mycelial growth of C. acutatum isolates (EC50 values of 0.01 to 0.55 mg/liter) but was ineffective against mycelium of G. candidum and B. dothidea isolates (EC50 values >300 mg/liter). The pyraclostrobin-boscalid mixture was highly effective against mycelium of C. acutatum (EC50 values of 0.01 to 0.05 mg/liter) and B. dothidea isolates (EC50 values of 0.02 to 0.03 mg/liter), but only marginally effective against mycelium of G. candidum (EC50 values 15.79 to 39.03 mg/liter). This study provides a diagnostic guide of pathogens that can cause summer diseases on ‘Babygold’ peaches and reports their in vitro sensitivity to registered respiration inhibitor fungicides.

Accepted for publication 23 December 2005. Published 1 March 2006.
Suppression of Fusarium Wilt of Watermelon Enhanced by Hairy Vetch Green Manure and Partial Cultivar Resistance
Authors: Zhou X. G. , Everts K. L.
Published: May 2008

Hairy vetch (Vicia villosa Roth) green manure is a newly-described potential management tool for Fusarium wilt of watermelon, but control is insufficient when watermelon, especially triploid watermelon, is grown in severely infested soils. A field experiment in a split-split-plot design was conducted over two years to evaluate efficacy of hairy vetch green manure alone and in combination with a moderately wilt-resistant (MR) triploid watermelon cultivar for wilt suppression compared with preplant soil fumigants. Either the soil-incorporated hairy vetch winter cover crop or the MR cultivar was effective in reducing wilt incidence, promoting plant vine growth, and increasing fruit yield. However, neither approach alone resulted in disease reductions sufficient to obtain an acceptable level of marketable fruit yield. An additive effect was observed when both treatments were combined and was greater than that obtained with the fumigants methyl bromide or metam sodium. Stem colonization by Fusarium oxysporum f. sp. niveum was lower following hairy vetch green manure than in fallow treatments, and was lowest in the MR cultivar grown in green-manured plots. The combined use of hairy vetch green manure and a MR cultivar can enhance suppression of Fusarium wilt in triploid watermelon.

Accepted for publication 25 February 2006. Published 5 April 2006.
Pink Hibiscus Mealybug Identification
Authors: Hodges Amanda , Hodges Greg
Published: May 2008

Identification of pink hibiscus mealybug is discussed in detail, including its symptoms and signs, host range, taxonomy, and geographic distribution, as well as methods of isolation, identification, and preservation.

Accepted for publication 18 March 2006. Published 14 April 2006.
Synopsis of Fungi Listed as Regulated Plant Pests by the USDA Animal and Plant Health Inspection Service: Notes on Nomenclature, Disease, Plant Hosts, and Geographic Distribution
Authors: Cline Erica T. , Farr David F.
Published: May 2008

To prevent the entry of exotic fungal pathogens, the Animal and Plant Health Inspection Service (APHIS) of the U.S. Department of Agriculture (USDA) has compiled a list of regulated plant pests of concern to the U.S., including more than 50 species of fungi that might cause serious economic or environmental damage. The fungi on the APHIS Regulated Plant Pest List represent some of the most significant threats to U.S. agriculture. For each of these fungal species, a synopsis was prepared that presents notes on nomenclature, disease, plant hosts, and geographic distribution. The following scientific names should be updated: Cercospora batatas (Pseudocercospora timorensis), Chrysomyxa ledi var. rhododendri (Chrysomyxa rhododendri), Crinipellis perniciosa (Moniliophthora perniciosa), Phacidiopycnis pseudotsugae (Allantophomopsis pseudotsugae), Pucciniastrum areolatum (Thekopsora areolata), and Stereum hiugense (Xylobolus hiugensis). Nomenclatural controversies are discussed for some species, including Diaporthe mali and Monilinia fructigena. Changes in nomenclature often reflect advances in taxonomic understanding, resulting in transfers to a different genus, modifications of lists of taxonomic synonyms, or establishing anamorph/teleomorph connections. These changes can have important implications for accurately determining the geographic distribution and host range of a fungus. Accurate information about scientific names, geographic distribution, and plant host range is essential in determining pest risk and in preventing the introduction and spread of invasive fungal pathogens.

Accepted for publication 18 March 2006. Published 5 May 2006.
Illustration of Key Morphological Characteristics of Phytophthora Species Identified in Virginia Nursery Irrigation Water
Authors: Bush Elizabeth A. , Stromberg Erik L. , Hong Chuanxue , Richardson Patricia A. , Kong Ping
Published: May 2008

Phytophthora diseases are commonly diagnosed on ornamental plants, but taxonomic identification to species can be intimidating. This illustrative guide is designed to aid diagnosticians in morphological identification of certain Phytophthora spp. that have been reported in irrigation and effluent water in nurseries. Using both morphological and molecular methods, the authors identify diagnostic characteristics that are consistent and easy to use.

Accepted for publication 6 April 2006. Published 21 June 2006.
Managing Botrytis Gray Mold in Greenhouse Tomatoes Using Traditional and Bio-Fungicides
Authors: Ingram David M. , Meister Charles W.
Published: May 2008

Eight fungicide products were evaluated over a three-year period to compare their efficacy in managing Botrytis gray mold in greenhouse tomatoes. Disease severity ratings indicated that STBX-016, Decree 50 WG, and Serenade ASO significantly reduced gray mold in two of three years as compared to the inoculated control. Milsana significantly reduced gray mold severity in only one of three years. Pristine and Switch reduced disease severity in the one year tested but Scala and Prestop did not. Switch, Milsana, and STBX-016 significantly increased marketable yield per plant in one of three years, as did Decree 50 WG in two of three years.

Accepted for publication 9 May 2006. Published 18 July 2006.
First Report of Phytophthora cambivora on Hybrid Rhododendron in North Carolina
Authors: Hwang J. , Warfield C. Y. , Parker K. C. , Benson D. M.
Published: May 2008

This is the first report of P. cambivora on Rhododendron spp. in North Carolina.

Accepted for publication 30 May 2006. Published 28 August 2006.
Method and Timing of Fungicide Applications for Control of Spring Dead Spot In Hybrid Bermudagrass
Authors: Butler E. Lee , Tredway Lane P.
Published: May 2008

The efficacy of five application methods and four fungicides were evaluated for control of spring dead spot (SDS) of bermudagrass from 2002 to 2004. Fenarimol and propiconazole were most effective in reducing SDS, providing from 66% to 89% and 51% to 52% control, respectively. Application water volume (2.5, 5, or 10 gal/1000 ft2), post-application irrigation, and high-pressure injection did not affect SDS control. Further research with fenarimol was conducted from 2003 into 2005 to optimize application rate and timing. In both years, all rates (6, 4 + 4, and 6 + 6 fl oz/1000 ft2, with split applications 2 weeks apart) provided equivalent control of SDS when averaged across all application timings. No significant differences were detected among application timings ranging from August 1 to October 1 in 2003 and from August 23 to November 5 in 2004.

Accepted for publication 22 May 2006. Published 1 September 2006.
Postharvest Fruit Rots in d'Anjou Pears Caused by Botrytis cinerea, Potebniamyces pyri, and Sphaeropsis pyriputrescens
Authors: Xiao C. L.
Published: May 2008

The ‘d'Anjou’ pear is the major winter pear variety in the US Pacific Northwest, and postharvest fruit rot diseases are a limiting factor for their long-term storage. The symptoms of the newly recognized diseases Phacidiopycnis rot and Sphaeropsis rot are similar to gray mold, and in fact, the new diseases are often misdiagnosed as gray mold. The objective of this article is to provide a practical guide to diagnosis of these three diseases.

Accepted for publication 30 May 2006. Published 5 September 2006.
Identifying and Distinguishing Seedling and Root Rot Diseases of Sugar Beets
Authors: Harveson Robert M.
Published: May 2008

Sugar beets are susceptible to a number of seedling and root rot diseases that constrain profitable sugar beet production. Since numerous environmental and cultural factors may cause symptoms that could be confused with symptoms caused by these pathogens, it is important to correctly identify and differentiate between various diseases and problems to effectively manage them. The goal of this guide is to assist in the identification and effective differentiation of various seedling and root rot diseases common to sugar beet.

Accepted for publication 7 June 2006. Published 15 September 2006.
Environmental deterioration increases tadpole vulnerability to predation
Authors: Squires Zoe E , Bailey Paul C.E , Reina Richard D , Wong Bob B.M
Published: May 2008

Human-induced environmental change is occurring at an unprecedented rate and scale. Many freshwater habitats, in particular, have been degraded as a result of increased salinity. Little is known about the effects of anthropogenic salinization on freshwater organisms, especially at sublethal concentrations, where subtle behavioural changes can have potentially drastic fitness consequences. Using a species of Australian frog (
Litoria ewingii
), we experimentally examined the effects of salinization on tadpole behaviour and their vulnerability to a predatory dragonfly nymph (
Hemianax papuensis
). We found that tadpoles exposed to an ecologically relevant concentration of salt (15% seawater, SW) were less active than those in our freshwater control (0.4% SW). Tadpoles in elevated salinity also experienced a higher risk of predation, even though the strike rate of the predator did not differ between salt and freshwater treatments. In a separate experiment testing the burst-speed performance of tadpoles, we found that tadpoles in saltwater were slower than those in freshwater. Thus, it would appear that salt compromised the anti-predator response of tadpoles and made them more susceptible to being captured. Our results demonstrate that environmentally relevant concentrations of aquatic contaminants can, even at sublethal levels, severely undermine the fitness of exposed organisms.
Fowl play and the price of petrel: long-living Procellariiformes have peroxidation-resistant membrane composition compared with short-living Galliformes
Authors: Buttemer William A , Battam Harry , Hulbert A.J
Published: May 2008

The membrane pacemaker hypothesis predicts that long-living species will have more peroxidation-resistant membrane lipids than shorter living species. We tested this hypothesis by comparing the fatty acid composition of heart phospholipids from long-living Procellariiformes (petrels and albatrosses) to those of shorter living Galliformes (fowl). The seabirds were obtained from by-catch of commercial fishing operations and the fowl values from published data. The 3.8-fold greater predicted longevity of the seabirds was associated with elevated content of peroxidation-resistant monounsaturates and reduced content of peroxidation-prone polyunsaturates and, consequently, a significantly reduced peroxidation index in heart membrane lipids, compared with fowl. Peroxidation-resistant membrane composition may be an important physiological trait for longevous species.
Predator-specific camouflage in chameleons
Authors: Stuart-Fox Devi , Moussalli Adnan , Whiting Martin J
Published: May 2008

A crucial problem for most animals is how to deal with multiple types of predator, which differ in their sensory capabilities and methods of prey detection. For animals capable of rapid colour change, one potential strategy is to change their appearance in relation to the threat posed by different predators. Here, we show that the dwarf chameleon,
Bradypodion taeniabronchum
, exhibits different colour responses to two predators that differ in their visual capabilities. Using a model of animal colour perception to gain a ‘predator's eye view’, we show that chameleons showed better background colour matching in response to birds than snakes, yet they appear significantly more camouflaged to the snake visual system because snakes have poorer colour discrimination.
Admixture determines genetic diversity and population differentiation in the biological invasion of a lizard species
Authors: Kolbe Jason J , Larson Allan , Losos Jonathan B , de Queiroz Kevin
Published: May 2008

Molecular genetic analyses show that introduced populations undergoing biological invasions often bring together individuals from genetically disparate native-range source populations, which can elevate genotypic variation if these individuals interbreed. Differential admixture among multiple native-range sources explains mitochondrial haplotypic diversity within and differentiation among invasive populations of the lizardAnolis sagrei. Our examination of microsatellite variation supports the hypothesis that lizards from disparate native-range sources, identified using mtDNA haplotypes, form genetically admixed introduced populations. Furthermore, within-population genotypic diversity increases with the number of sources and among-population genotypic differentiation reflects disparity in their native-range sources. If adaptive genetic variation is similarly restructured, then the ability of invasive species to adapt to new conditions may be enhanced.