February 2, 2006, 8:20 PM CT

A Heartier Apple Tree

wild apple trees in central Asia may revolutionize the nation's apple industry.

This material shows potential for helping breed trees that bear popular, domestic apples while standing up to destructive diseases and fungi, as per Agricultural Research Service (ARS) scientists. The genetic material was gathered during U.S. Department of Agriculture (USDA) sponsored excursions to Asia and Europe aimed at expanding the known genetic diversity of apples.

Horticulturist Phil Forsline and plant geneticist Gennaro Fazio of ARS' Plant Genetics Research Unit have used the material to raise orchards of the exotic apples near their laboratory in Geneva, N.Y. And, with colleagues in ARS and Cornell University, they've documented with astonishment the disease resistance of a number of of these trees and the domestic species they've bred with them.

Forsline went on seven of the collecting trips, including four to central Asia. The trips resulted in at least a doubling of the known genetic diversity of apple trees, as per Forsline. The researchers returned with 949 apple tree accessions from central Asia alone. Other excursions were to China, the Caucasus region including Russia and Turkey, and Gera number of.

Fazio and Forsline are most impressed with the material collected in Kazakhstan, particularly accessions of Malus sieversii, an important forerunner of the domestic apple. This is logical, given that Kazakhstan is a likely ancestral origin of familiar domestic apples (Malus x domestica) such as Red Delicious, Golden Delicious and McIntosh.........

Posted by: Jessica      Permalink


January 28, 2006, 6:00 PM CT

Biomass To Reduce Fossil Fuel Dependence

Using plants rather than oil or coal to produce fuels and chemicals could play an essential role in reducing the world's dependence on fossil fuels, as per a group of researchers from the UK and the USA writing today in the journal Science.

The researchers from Imperial College London, Georgia Tech and Oak Ridge National Laboratory have evaluated the scientific and technological potential of a future based on renewable plant matter and biological material such as trees, grasses, agricultural crops, known as biomass. Their conclusions form the basis of a strategic alliance between the three institutions, the AtlantIC Alliance.

Today's paper describes the scientific challenges of creating a facility to process all the components of biomass. Such a facility would make a range of fuels, foods, chemicals, animal feeds, materials, heat and power in proportions that would give maximum value with minimum waste.

The researchers think that efficient refining of biomass will be vital for producing renewable products with reduced carbon emissions. Biofuels and biomaterials are derived from plants which take carbon dioxide from the atmosphere as they grow. Their net contribution to the addition of greenhouse gases can be very small if minimal non-renewable energy is used when processing them into useful material or energy products.........

Posted by: Erica      Permalink


January 24, 2006, 4:44 PM CT

Bacterial Genome Sequenced From Ancient Salterns

Tourists in Spain often stop to ogle the country's a number of saltwater lagoons, used to produce salt since Roman times. Scientists, too, admire these saltern crystallizers-and even more so, the microbes that manage to survive in such briny environs. Now, reporting in the November 28-December 2 early online edition of the Proceedings of the National Academy of Sciences, scientists at The Institute for Genomic Research and collaborators reveal the genome of one bacterium at home in the salty Spanish ponds.

The bacterium is Salinibacter ruber , a bright red, rod-shaped organism. Several years ago, researchers first isolated S. ruber from saltern crystallizer ponds in Alicante and Mallorca , Spain. Eventhough extreme-loving microbes called archaea were known to eke out life in the ponds, researchers were surprised to discover ordinary bacteria also thriving in such a physically demanding environment, at salt concentrations up to 30 percent. How could these microbes-which normally prefer milder environments-thrive in such high salt?

To find out, TIGR scientists Emmanuel Mongodin and Karen Nelson, working with Canadian and Spanish colleagues, set out to sequence S. ruber 's genome. In doing so, the researchers discovered evidence that the resourceful bacterium independently evolved some salt-surviving biochemistry. More surprising, S. ruber apparently also borrowed some genes from neighboring archaeal species, in an unusual example of cross-domain lateral gene transfer.........

Posted by: Ashley      Permalink


January 24, 2006, 3:46 PM CT

Sequence Three Fungus Genomes

From garden compost to forest greenery, the mold Aspergillus fumigatus lurks across much of the world. And so does its impact. The most common mold causing infection, A. fumigatus triggers allergic reactions, asthma attacks--and even deadly infections among people with weakened immune systems.

Now, in the December 22 issue of the journal Nature, researchers at The Institute for Genomic Research (TIGR) and their collaborators report the mold's sequenced genome. The genome could lead scientists to A. fumigatus genes with the potential to generate better diagnostics and therapy for fungal infection. "This genome sequence is going to be central for developing tools for effectively managing A. fumigatus infections as they become more prevalent in the aging population," predicts first author William Nierman, a microbiologist at TIGR.

Nierman co-authored two additional Aspergillus genome papers in the same issue of Nature. One describes a genome project on Aspergillus oryzae, a nonpathogenic food industry workhorse that has produced sake (rice wine), miso (soybean paste), and shoyu (soy sauce) for 2,000 years. The third paper reports the genome sequence of model organism Aspergillus nidulans and compares the organism to A. oryzae and A. fumigatus. The work was carried out collaboratively at several institutions in the U.S., U.K., Spain, Japan, France, Brazil, Austria, Switzerland, and Gera number of. David Denning of the University of Manchester coordinated the projects.........

Posted by: Ashley      Permalink


January 23, 2006, 9:19 PM CT

citrus greening can be managed

Canker topped the list of worries for the Florida citrus industry until citrus greening - described as the world's most serious citrus disease - was found in groves last year.

"In the long term, the industry can live with and manage the canker problem, but citrus greening is a fatal disease that's an even larger threat to the state's signature crop," said Harold Browning, director of the University of Florida's Citrus Research and Education Center in Lake Alfred. "In other areas of the world where greening is a problem, it has never been successfully eradicated".

The disease, which slowly weakens and kills all types of citrus trees, causes fruit to become lopsided and taste bitter, making it unusable. Fruit does not develop the desired color, hence the greening name. There is no known cure for the disease, which is on the U.S. Department of Agriculture's select list of threats to plants and wildlife regulated by the Agricultural Bioterrorism Protection Act. Greening does not harm people.

Browning said the fatal bacterial disease is transmitted by the Asian citrus psyllid (Diaphorina citri), a tiny insect that is now widely distributed throughout Florida, and the disease has been found in more than 440 locations in 11 counties. Browning said it's not practical to eradicate citrus greening, but the spread of the disease can be slowed with an effective integrated pest management program (IPM) that includes limited use of systemic insecticides and beneficial insects that attack the psyllid.........

Posted by: Erica      Permalink


January 20, 2006, 3:21 PM CT

Increased Competition For Pollen

The decline of birds, bees and other pollinators in the world's most diverse ecosystems may be putting plants in those areas at risk, according to new research. The finding raises concern that more may have to be done to protect Earth's most biologically rich areas, scientists say in an article appearing in the Jan. 17 issue of the Proceedings of the National Academy of Sciences (PNAS).

The analysis shows that ecosystems with the largest number of different species, including the jungles of South America and Southeast Asia and the rich shrubland of South Africa, have bigger deficits in pollination compared to the less-diverse ecosystems of North America, Europe and Australia.

"The global pattern we observed suggests that plants in species-rich regions exhibit a greater reduction in fruit production due to insufficient pollination than plant species in regions of lower biodiversity," said Susan Mazer, a co-author of the article and a biologist at the University of California, Santa Barbara. Typically typically she and her colleagues believe such biodiversity "hotspots" are characterized by stronger competition among plant species for pollinators, such that many plant species simply don't receive enough pollen to achieve maximum fruit and seed production.

"Many plants rely on insects and other pollen vectors to reproduce," said Jana Vamosi, an evolutionary biologist at the University of Calgary and co-author of the paper. "We've found that in areas where there is a lot of competition between individuals and between species, many plants aren't getting enough pollen to successfully reproduce. If plants can't survive, neither can animals. These biodiversity hotspots are important because they are where we most often find new sources of drugs and other important substances. They are also the areas where habitat is being destroyed the fastest".........

Posted by: Erica      Permalink


January 17, 2006, 0:12 AM CT

Genetically Modified Crops For Economic Growth

Developing countries are playing an important role in the expansion of genetically modified (GM) crops, and are set to play an increasingly important role both in growing and researching the plants in the next ten years, says a report from the Council for Biotechnology Information.

The Global Diffusion of Plant Biotechnology 2004 report shows that over the past decade, the fastest growth of GM crops has been in developing countries.

Globally, planting of GM crops has increased at an annual rate of 15 per cent since they were first introduced in the mid-1990s, says the UN Food and Agriculture Organisation (FAO). If this rate were sustained, the global market would reach US$210 billion by 2014, nearly a five-fold increase from its current US$44 billion value.

In its report, the Council for Biotechnology argues that developing nations stand to benefit most from this growth. It says the gross domestic product of poor nations adopting GM crops could increase by as much as two per cent by 2014.

Prabhu Pingali and Terri Raney of the FAO's Agricultural and Development Economics Division, told SciDev.Net that sustaining the 15 per cent growth rate would depend on the development of new crops meeting the needs of developing nations, and on ensuring such countries can access and adopt them.........

Posted by: Jaison      Permalink


January 7, 2006, 4:39 PM CT

Snails in Southeastern Salt Marshes

Periwinkles, the spiral-shelled snails usually found along rocky U.S. shorelines, play a primary role in the unprecedented disappearance of salt marsh in the southeastern states, according to new research published in Science.

Based on extensive field studies, the work challenges six decades of salt marsh science. Ecologists have long thought that stressed soil - too much salt, not enough oxygen - was the main killer of this critical marine habitat.

But Brian Silliman, a Brown University research fellow and a University of Florida assistant professor, said drought-stressed soils pave the way for predatory periwinkles that spread fungal disease as they graze on cordgrass.

"Snails can transform healthy marsh to mudflats in a matter of months," said Silliman, lead author of the Science paper. "This finding represents a huge shift in the way we see salt marsh ecology. For years, researchers thought marsh die-off was simply a 'bottom-up' problem related solely to soil conditions. We found that the trouble also comes from the top down. Drought makes the marsh vulnerable, then the snails move in".

Thousands of acres of salt marsh have disappeared from South Carolina to Texas since 2000, according to several scientific studies. In Louisiana alone, more than 100,000 acres of marsh were severely damaged between June 2000 and September 2001. This drastic decline poses a serious threat to the ecology and economy of the southeastern seaboard and the Gulf Coast. Salt marshes serve as nursery grounds that support commercial fisheries, protect coastline from storm-induced floods, and filter fresh water before it flows out to sea.........

Posted by: Ashley      Permalink


January 4, 2006, 11:11 PM CT

As Amazon's Tree Line Recedes

Scientists have long known that chronic deforestation can spawn a jungle of environmental woes. But now, a study confirms that vanishing forests inflict more than environmental damage: they may cause human diseases, too.

Working in the Peruvian Amazon, a team of researchers from UW-Madison and Johns Hopkins University found that malaria-inducing mosquitoes are likely to bite humans more than 200 times more often in cleared areas versus forested ones. Their results appear this week in the American Journal of Tropical Medicine and Hygiene (Jan. 6, 2005).

"By dramatically changing the landscape, we are tipping the balance in a way that is increasing the risk of malaria transmission," says senior author Jonathan Patz, a former Johns Hopkins scientist and now a professor both in UW-Madison's Nelson Institute for Environmental Studies and the department of population health. "This is one of the most detailed quantitative field studies in the Amazon that directly addresses the potential link between deforestation and malaria".

Over one year, the research team collected mosquitoes at 56 sites in varying stages of deforestation. The sites were located around 14 villages situated along a new road that cuts through the Amazonian rainforest, and connects the towns of Iquitos and Nauta in northeastern Peru. Working in the evenings when mosquitoes are at their thirstiest, the scientists counted how often the insects landed on humans at every site, each of which had been assigned to one of four vegetation categories, including rainforest, shrubby regrowth, cultivated areas and populated villages.........

Posted by: Ashley      Permalink


January 2, 2006, 11:18 PM CT

Forests And Global Warming

Growing a forest might sound like a good idea to combat global warming, since trees draw carbon dioxide from the air and release cool water from their leaves. But they also absorb sunlight, warming the air in the process. According to a new study from the Carnegie Institution's Department of Global Ecology and Lawrence Livermore National Laboratory, planting forests at certain latitudes could make the Earth warmer. Carnegie's Ken Caldeira will present the work at the American Geophysical Union Fall Meeting in San Francisco on December 7, 2005.

The scientists used complex climate modeling software to simulate changes in forest cover and then examined the effects on global climate. Their results were surprising. "We were hoping to find that growing forests in the United States would help slow global warming," Caldeira said. "But if we are not careful, growing forests could make global warming even worse".

The scientists found that while tropical forests help keep Earth cool by evaporating a great deal of water, northern forests tend to warm the Earth because they absorb a lot of sunlight without losing much moisture. In one simulation, the scientists covered much of the northern hemisphere (above 20° latitude) with forests and saw a jump in surface air temperature of more than 6° F. Covering the entire planet's land mass with trees led to a more modest increase of about 2° F.........

Posted by: Jaison      Permalink