Landscape tree disease from 12 wood decay fungi studied

Results help predict tree failures, estimate damage from diseased trees

2010-12-31

(Press-News.org) STONEVILLE, MS – Landscape trees, valued for their aesthetic nature and their environmental benefits, are becomingly increasingly valuable in urban environments. A single mature tree can add considerable value to commercial and residential properties. Conversely, tree mortality can result in significant economic losses. Urban trees must endure adverse growing conditions that reduce their structural strength and subject them to stresses, predisposing them to disease. One particularly devastating pathogen, wood-rotting fungi, can compromise the stability of urban trees, resulting in injuries to people and property damage from falling trees and limbs. Wood decay fungi are the primary and most common cause of failure in standing trees.

A study in HortScience investigated the in vitro development of decay caused by 12 major root-rot and trunk-rot fungi in sapwood extracted from nine ornamental and landscape tree species native to southern temperate forests in the Mississippi Delta region. Scientists Manuela Baietto and A. Dan Wilson compared the relative wood decay potential and host specificity of damage associated with these wood-rotting fungi, and determined the relative in vitro susceptibility or resistance of sapwood from each tree species to decay over 1-year and 2-year incubation periods.

Strains of Armillaria mellea, Ganoderma lucidum, and Heterobasidion annosum exhibited the highest decay potential in most tree species tested. According to the study, the order of fungi causing the greatest decay varied over time as a result of temporal changes in decay-rate curves. Relative wood durability or resistance to decay generally was greater in gymnosperm than in angiosperm wood types. Quercus nuttallii, Fraxinus pennsylvanica, and Quercus lyrata sustained the highest levels of decay by all fungi. Northern white cedar (Thuja occidentalis) sapwood was most resistant to decay by all rot-fungi tested, sustaining only limited weight loss after 1 and 2 years of decay, although sapwood of Pinus taeda, Liquidambar styraciflua, and Platanus occidentalis had relatively low levels of decay after 2 years.

Baietto and Wilson observed that the data from their study will be useful in making general assessments of the hazard status of individual urban tree, and can be combined with data from urban tree assessment surveys to predict future tree failures and estimate potential damage from falling tree parts. The information is useful for urban forestry professionals in developing individual tree inspection and maintenance schedules that help avoid personal and property damage resulting from structural failures of landscape trees.

### The complete study and abstract are available on the ASHS HortScience electronic journal web site: http://hortsci.ashspublications.org/cgi/content/abstract/45/3/401

Founded in 1903, the American Society for Horticultural Science (ASHS) is the largest organization dedicated to advancing all facets of horticultural research, education, and application. More information at ashs.org

ELSE PRESS RELEASES FROM THIS DATE:

Researchers discover potential solutions to New England roadside erosion

2010-12-31

KINGSTON, RI – Erosion is a significant problem on highway embankments in New England. To mitigate erosion on the regions' highways, slopes are seeded with a grass–legume mixture that usually including red fescue, a grass preferred for its drought-tolerance and ability to thrive in acidic, infertile soil. "A mixture of red fescue, perennial ryegrass, and kentucky bluegrass is planted to stabilize the soil, but only the red fescue survives long term on slopes", noted Rebecca Nelson Brown, lead author of a report in HortScience. Brown and a team from the Department of Plant ...

Improving nitrogen use efficiency lessens environmental impact

2010-12-31

ITALY – Most agricultural crops require large quantities of nitrate-rich fertilizer to realize optimal yields. The dilemma for growers is finding ways to balance the amount of nitrogen needed for production while minimizing potentially harmful nitrates that can leach into ground and surface waters. Increased interest in environmentally beneficial "low-input" approaches is challenging researchers to identify genotypes that have a characteristic called "high nutrient use efficiency", or NUE. Using vegetable types with high NUE could help growers lessen environmental impacts ...

Can bedding plants thrive with recyled water?

2010-12-31

EL PASO, TX – To conserve dwindling water resources, municipalities are encouraging the use of "recycled water", municipal wastewater that has been extensively treated and deemed safe to reuse for irrigation and other purposes. Using recycled water can be cost-effective and helps conserve the potable supply. In areas of the U.S. where production of bedding plants means income and jobs, commercial growers are looking for ways to use reclaimed or recycled water for irrigation, but using recycled water does not come without challenges. The water can contain high levels of ...

April grafting optimal for Fraser fir

2010-12-31

RALEIGH, NC – Christmas trees provide a significant source of revenue in southern Appalachia, resulting in millions of dollars in sales during the holiday buying season. The most popular species in the region is fraser fir, appreciated for its fragrance and consumer-friendly traits such as soft needles, strong branches, exceptional needle retention, and natural Christmas tree shape. Frasers, indigenous to isolated high-elevation mountains in southwestern Virginia, western North Carolina, and eastern Tennessee, are under attack by a pathogen called Phytophthora cinnamom, ...

Large-scale analysis identifies new genetic alterations associated with height

2010-12-31

A large collaborative study has added to the growing list of genetic variants that determine how tall a person will be. The research, published by Cell Press on December 30 in the American Journal of Human Genetics, identifies uncommon and previously unknown variants associated with height and might provide insight into the genetic architecture of other complex traits. Although environmental variables can impact attained adult height, it is clear that height is primarily determined by specific alleles that an individual inherits. Height is thought to be influenced by ...

New test announced for major killer of lung transplant patients

2010-12-31

ANN ARBOR, Mich. — A lung transplant can mean a new chance at life. But many who receive one develop a debilitating, fatal condition that causes scar tissue to build up in the lungs and chokes off the ability to breathe. University of Michigan researchers hope a new diagnostic tool they developed to predict bronchiolitis obliterans syndrome (BOS) will allow doctors to intervene earlier and, ultimately, to provide life-saving treatments. BOS is the leading cause of death for those who survive one year after lung transplantation and more than half of recipients will develop ...

First come, first served?

2010-12-31

Emergency department overcrowding can result in long waiting times for seriously ill patients. They then compete with patients with less severe illnesses for the next available treatment. In this edition of Deutsches Ärzteblatt International (Dtsch Arztebl Int 2010; 107[50]: 892𔃆), Michael Christ and his coauthors provide an overview of current practice for initial assessment of emergency patients. Triage provides reliable methods that can be used to assess the severity of an illness and the urgency of treatment in emergency departments. In English-speaking countries, ...

What triggers mass extinctions? Study shows how invasive species stop new life

2010-12-31

An influx of invasive species can stop the dominant natural process of new species formation and trigger mass extinction events, according to research results published today in the journal PLoS ONE. The study of the collapse of Earth's marine life 378 to 375 million years ago suggests that the planet's current ecosystems, which are struggling with biodiversity loss, could meet a similar fate. Although Earth has experienced five major mass extinction events, the environmental crash during the Late Devonian was unlike any other in the planet's history. The actual number ...

Was Israel the birthplace of modern man?

2010-12-31

Tel Aviv ― It has long been believed that modern man emerged from the continent of Africa 200,000 years ago. Now Tel Aviv University archaeologists have uncovered evidence that Homo sapiens roamed the land now called Israel as early as 400,000 years ago ― the earliest evidence for the existence of modern man anywhere in the world. The findings were discovered in the Qesem Cave, a pre-historic site located near Rosh Ha'ayin that was first excavated in 2000. Prof. Avi Gopher and Dr. Ran Barkai of Tel Aviv University's Department of Archaeology, who run the excavations, ...

New technology to speed cleanup of nuclear contaminated sites

2010-12-31

CORVALLIS, Ore. – Members of the engineering faculty at Oregon State University have invented a new type of radiation detection and measurement device that will be particularly useful for cleanup of sites with radioactive contamination, making the process faster, more accurate and less expensive. A patent has been granted on this new type of radiation spectrometer, and the first production of devices will begin soon. The advance has also led to creation of a Corvallis-based spinoff company, Avicenna Instruments, based on the OSU research. The market for these instruments ...

New study charts how Earth’s global temperature has drastically changed over the past 485 million years, driven by carbon dioxide

Scientists say we have enough evidence to agree global action on microplastics

485 million-year temperature record of Earth reveals Phanerozoic climate variability

[Press-News.org] Landscape tree disease from 12 wood decay fungi studied
Results help predict tree failures, estimate damage from diseased trees

Landscape tree disease from 12 wood decay fungi studied

ELSE PRESS RELEASES FROM THIS DATE:

LAST 30 PRESS RELEASES: