Bacterial endophytes from wild and ancient maize are able to suppress the fungal pathogen Sclerotinia homoeocarpa.

AIMS: The aim of this study was to determine if endophytes from wild and ancient Zea plants (corn family) have anti-fungal activities, specifically against the most important fungal pathogen (Sclerotinia homoeocarpa) of creeping bentgrass, a relative of Zea, used here as a model grass. METHODS AND RESULTS: A library of 190 bacterial endophytes from wild, ancient and modern Zea plants were tested for their ability to suppress S. homoeocarpa in vitro, followed by in planta testing of candidates using greenhouse trials. Three endophytes could suppress S. homoeocarpa, originating from wild maize and an ancient Mexican landrace, consistent with our hypothesis. 16S phylogenetic analysis and BOX-PCR DNA fingerprinting suggest that the anti-fungal endophytes are distinct strains of Burkholderia gladioli. One strain (3A12) was confirmed to colonize creeping bentgrass using green fluorescent protein (GFP) tagging. Evans blue vitality staining demonstrated that the bacterial endophytes exhibited fungicidal activities against the pathogen. The endophytes inhibited a wide spectrum of plant-associated fungi including diverse crop pathogens. CONCLUSIONS: The results support the hypothesis that wild and ancient Zea genotypes host bacterial endophytes that can control fungal pathogen(s). SIGNIFICANCE AND IMPACT OF THE STUDY: These results suggest that wild and ancient crops may be an unexplored reservoir of anti-fungal bacterial endophytes.

First Report of Magnaporthe poae, Cause of Summer Patch Disease on Annual Bluegrass, in Canada.

The ectotrophic, root-infecting fungus Magnaporthe poae Landschoot & Jackson, the causal agent of summer patch disease in the U.S. (2), is implicated in the damage and loss of annual bluegrass (Poa annua L.) on golf course greens. This pathogenic fungus, one of the important root pathogens of turfgrass, attacks and colonizes susceptible turfgrass roots suffering from environmental or cultural stresses. Over 100 turf samples that exhibited symptoms (chlorotic circular or irregular patches of ≥15 cm in diameter with necrotic crowns and discolored roots) reminiscent of summer patch were collected from 77 southwestern Ontario golf courses from July to August of 2009 and 2010. Roots and crowns were often covered with dark, ectotrophic runner hyphae, lobed hyphopodia, and growth cessation structures, characteristic of M. poae. Sections of root tissue were surface sterilized in 0.6% sodium hypochlorite (NaOCl) for 5 min. Sterilized root tissue was plated on potato dextrose agar (PDA) containing 50 mg L-1 streptomycin sulfate and incubated at 28°C for 7 to 10 days. A fungus with morphological characteristics (hyaline mycelium that appears gray or olive-brown when mature) similar to those of M. poae (1) was consistently isolated (≥100 isolates were obtained) and used to identify M. poae through molecular techniques and Koch's postulates. DNA was extracted from the fungal mycelium of the collected isolates using the PowerPlant DNA isolation kit (MO BIO Laboratories, Inc., Carlsbad, CA). The rDNA internal transcribed spacer (ITS) regions of the isolates (≥100 isolates) were amplified by PCR using universal fungal rDNA primers ITS 4 (5'-TCCTCCGCTTATTGATATGC-3') and ITS 5 (5'- GGAAGTAAAAGTCGTAACAAGG-3') (3). The purified PCR products were sequenced (GenBank Accession No. JX134588 through JX134601) and a BLAST search exhibited seven isolates with 99% (MAG3, MAG6, MAG13, MAG16, and MAG17) and 100% (MAG1 and MAG14) similarity to M. poae in the GenBank database. Pathogenicity of four isolates (MAG1, MAG3, MAG6, and MAG14) was confirmed with Koch's postulates. Sixteen healthy P. annua core samples (four replicates of each treatment/isolate) collected from an Ontario golf course were inoculated with 25 mg M. poae-infested Kentucky bluegrass seed (Poa pratensis L.; 12.5 mg inoculum applied at the surface of the potting medium and 12.5 mg inoculum applied on the foliar surface) and were placed in a growth chamber with 12-h day/night cycles at 30/25°C and approximate relative humidity. After 2 to 3 weeks, inoculated plants exhibited chlorotic foliage and necrotic roots covered with dark ectotrophic runner hyphae and lobed hyphopodia. Infected root sections from each replication were surface sterilized and placed on PDA containing 50 mg L-1 streptomycin sulfate. The fungal cultures exhibited morphological characteristics consistent with M. poae (1). To our knowledge, this is the first report of summer patch caused by M. poae in Canada. References: (1) B. B. Clarke and A. B. Gould, eds. Turfgrass Patch Diseases Caused by Ectotrophic Root-Infecting Fungi. The American Phytopathological Society, St. Paul, MN, 1993. (2) P. J. Landschoot and N. Jackson. Mycol. Res. 93:59, 1989. (3) T. J. White et al. Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics. Pages 315-322 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al. eds. Academic Press, San Diego, CA, 1990.

Population Dynamics of Plant-Parasitic Nematodes in Golf Course Greens Turf in Southern New England.

The distribution, frequency, and population levels over time of plant-parasitic nematodes were surveyed on 114 greens from 38 different golf courses throughout southern New England. Sampling took place in the spring, summer, and fall of 2003 and 2004. The predominant genera of phytoparasitic nematodes recovered from soil samples were Tylenchorhynchus, Helicotylenchus, Criconemella, Hoplolaimus, and Heterodera. Tylenchorhynchus and Helicotylenchus spp. were the most common, found in all 38 golf courses sampled. Population levels were significantly higher (α = 0.05) in 2004 than in 2003 for Criconemella, Tylenchorhynchus, and Heterodera juveniles. There was a significant effect of season on population levels of Criconemella, Tylenchorhynchus, and Heterodera juveniles in the 2003 sampling year, and on Helicotylenchus, Tylenchorhynchus, and Heterodera juveniles in 2004. Population levels were highest in the fall for all genera except for Tylenchorhynchus, which were highest in the summer for both years. The results of this study suggest that parasitic nematodes are present in relatively high numbers in golf course turf soils in southern New England, and that there are variations in the dynamics of population levels among the different genera found in the area.

Fluid resuscitation in acutely injured patients.

Injuries are the third leading cause of death in the United States, exceeded only by heart disease and cancer. The success of resuscitation after an acute injury is dependent on providing adequate oxygenation, restoring intravascular fluid volume, and maintaining optimum cardiac output and cellular perfusion. Fluid resuscitation is essential to the successful management of hemorrhagic shock; it involves obtaining venous access, administration of the appropriate type and amount of fluid and blood products, and ongoing monitoring of the patient. There are special considerations in fluid resuscitation for the pediatric and burn patient. Care of the trauma patient is a dynamic process and requires ongoing evaluation of clinical parameters. Fluid resuscitation is a central component in the overall management of the trauma patient.

Air bags: a major advance in injury control.

Motor vehicle related injury is the number one cause of injury related to morbidity and mortality, exceeding 5 million injuries per year. There is a growing body of scientific evidence that motor vehicles equipped with air bags make a significant impact in reducing both the severity of injury and the overall fatality rate. Nurses are a key resource in the prevention and mitigation of motor vehicle related injury. Nurses must not only be knowledgeable in the vital role that air bags play in motor vehicle crashes, but actively promote and educate individuals and groups regarding injury prevention programs that focus on air bags. Nurses also play an essential role in this approach to injury through the development of partnerships among businesses, government, health care, community groups, and consumers.

A 39-year-old man with acute hemolytic crisis secondary to intravenous injection of hydrogen peroxide.

The diagnosis of cancer or its recurrence is often emotionally devastating for patients and those close to them. People may have a great deal of difficulty accepting the diagnosis and may seek others' opinions about the best course of treatment. When a physician projects that there is no hope, or if a cure is no longer probable, the patient and those close to him or her may feel helpless and hopeless. Given the resultant psychologic turmoil, the patient may be led to try unproven methods. Such methods, often referred to as "cancer quackery," represent a person's attempt to reassert personal control in response to these feelings of helplessness and hopelessness. Cancer quackery involves about $2 billion each year in the United States alone. One study demonstrated that approximately 39% of the pediatric outpatients studied had either tried, considered, or received recommendations for unproven methods of cancer treatment. Laetrile and faith healing were the most frequent methods used. One of the most recent of the unproven methods of cancer treatment that have been shown to cause life-threatening complications is IV injection of hydrogen peroxide. The scientific rationale behind this procedure is still unclear, but the side effects are clearly life threatening.

Assessment of the person with AIDS in the emergency department.

It is difficult to describe a "typical" clinical picture of a person with acquired immunodeficiency syndrome (AIDS) who is seen in the emergency department. The clinical course and the early clinical manifestations that lead to the initial diagnosis of AIDS vary greatly. Variability is the rule, because the patient with AIDS may manifest a wide range of signs and symptoms--from those associated with a minor illness to those indicative of a critical near-death state. Indeed, some patients with AIDS have no complaints or relatively minor constitutional complaints before becoming acutely compromised as a result of an overwhelming opportunistic infection. Other patients have a relatively short history (weeks to months) of vague, nonspecific complaints.

Perception of treatment needs: differences between patients and staff of a drug abuse treatment program.

Patients and staff of the Seattle Veterans Administration Drug Dependency Treatment Program were surveyed to elicit their perception of treatment priorities in establishing a series of educationally oriented short-term groups. Comparisons of priorities were made between patients and staff, methadone and polydrug patients, and patients with alcohol problems and those without alcohol problems. After the survey a series of short-term groups was established and attendance was kept. It was found in general that the groups which patients thought had higher priority in their treatment--including drug and medical information, stress management, and money management--were better attended.