January 16, 2011, 8:39 PM CT

LCD projector used to control brain and muscles of tiny organisms

Scientists are using inexpensive components from ordinary liquid crystal display (LCD) projectors to control the brain and muscles of tiny organisms, including freely moving worms. Red, green and blue lights from a projector activate light-sensitive microbial proteins that are genetically engineered into the worms, allowing the scientists to switch neurons on and off like light bulbs and turn muscles on and off like engines.

Use of the LCD technology to control small animals advances the field of optogenetics -- a mix of optical and genetic techniques that has given scientists unparalleled control over brain circuits in laboratory animals. Until now, the technique could be used only with larger animals by placement of an optical fiber into an animal's brain, or mandatory illumination of an animal's entire body.

A paper published Jan. 9 in the advance online edition of the journal Nature Methods describes how the inexpensive illumination technology allows scientists to stimulate and silence specific neurons and muscles of freely moving worms, while precisely controlling the location, duration, frequency and intensity of the light.

"This illumination instrument significantly enhances our ability to control, alter, observe and investigate how neurons, muscles and circuits ultimately produce behavior in animals," said Hang Lu, an associate professor in the School of Chemical & Biomolecular Engineering at the Georgia Institute of Technology......... Posted by: Kelly      Read more         Source

January 11, 2011, 6:54 AM CT

Strawberry Genome Sequence Promises Better Berries

An international team of researchers, including several from the University of New Hampshire, have completed the first DNA sequence of any strawberry plant, giving breeders much-needed tools to create tastier, healthier strawberries. Tom Davis, professor of biological sciences at UNH, and postdoctoral researcher Bo Liu were significant contributors to the genome sequence of the woodland strawberry, which was published last month in the journal Nature Genetics.

"We now have a resource for everybody who's interested in strawberry genetics. We can answer questions that before would have been impossible to address," says Davis, who has been working on the strawberry genome project since 2006 as part of the international Strawberry Genome Sequencing Consortium.

For instance, says Davis, breeders can now look at the DNA "fingerprint" of strawberry plants to more easily breed those with enhanced flavor, aroma, or antioxidant properties. Or they could breed more disease-resistant berries, decreasing the significant amount of spraying that cultivated strawberries currently need to thrive and thus enhancing the berry's healthful qualities.

Further, the woodland strawberry is a member of the Rosaceae family, which includes apples, peaches, cherries, raspberries, and almonds, all economically important and popular crops; scientists say the DNA sequence of the strawberry genome will inform the breeding of these other fruits. "We can now begin to understand how evolution works at the level of the genome on this family of plants we all enjoy," says Davis......... Posted by: Erica      Read more         Source

January 11, 2011, 6:44 AM CT

Miscanthus has a fighting chance against weeds

University of Illinois research reports that several herbicides used on corn also have good selectivity to Miscanthus x giganteus (Giant Miscanthus), a potential bioenergy feedstock.

"No herbicides are currently labeled for use in Giant Miscanthus grown for biomass," said Eric Anderson, an instructor of bioenergy for the Center of Advanced BioEnergy Research at the University of Illinois. "Our research shows that several herbicides used on corn are also safe on this rhizomatous grass".

M. x giganteus is sterile and predominantly grown by vegetative propagation, or planting rhizomes instead of seed. This can be a very costly investment and requires a 1- to 2-year establishment period. Anderson's research showed that Giant Miscanthus does not compete well with weeds during establishment, particularly early emerging weeds.

"There's a great cost in establishing Giant Miscanthus," Anderson said. "It's important to protect this investment, particularly if it goes commercial. When weeds outcompete Giant Miscanthus, the result is stunted growth and lack of tillering. Basically, you are risking the crop's ability to overwinter".

The study, funded by the Ingersoll Fellowship, the Illinois Council on Food and Agricultural Research and the Energy Biosciences Institute, screened 16 post-herbicides and 6 pre-herbicides in a greenhouse setting. Several herbicides, especially those with significant activity on grass species, caused plant injury ranging from 6 to 71 percent and/or reduced M. x giganteus dry mass by 33 to 78 percent......... Posted by: Erica      Read more         Source

January 11, 2011, 6:30 AM CT

Lake Erie hypoxic zone doesn't affect all fish

Large hypoxic zones low in oxygen long have been thought to have negative influences on aquatic life, but a Purdue University study shows that while these so-called dead zones have an adverse affect, not all species are impacted equally.

Tomas Hook, an assistant professor of forestry and natural resources, and former Purdue postdoctoral researcher Kristen Arend used output from a model to estimate how much dissolved oxygen was present in Lake Erie's hypoxic zone each day from 1987 to 2005. That information was compared with biological information for four fish species to assess the hypoxic zone's impact on the sustainability of their habitats.

"The term 'dead zone' sounds really scary," Hook said. "But in a lot of cases a hypoxic zone will not be negative for all fish species".

Lake Erie's hypoxic zone is very large - about the size of Rhode Island and Delaware combined. And while the Gulf of Mexico's dead zone has received more attention, during some years Lake Erie's zone appears to be greater in volume.

Hypoxia occurs when water has less than two parts per million of dissolved oxygen. Discharge of nutrients, such as nitrogen and phosphorus, leads to excess algae growth. When that algae settles to the bottom and decomposes, oxygen is consumed......... Posted by: Kelly      Read more         Source

January 11, 2011, 6:13 AM CT

Shellfish is now safer to eat

New technology to make shellfish safer to eat has been pioneered by researchers at Queen's University Belfast.

The new test, developed at Queen's Institute for Agri-Food and Land Use, not only ensures shellfish are free of toxins before they reach the food chain but is likely to revolutionise the global fishing industry.

While the current process for monitoring potentially dangerous toxins in shellfish takes up to two days, the new test slashes the testing time to just 30 minutes using new biosensor technology and provides a much more reliable result.

The test detects paralytic shellfish poisons, which paralyse anyone who consumes them and kills around 25 per cent people who are poisoned.

Leading the project is Professor Chris Elliott, Director of the Institute of Agri-Food and Land Use at Queen's School of Biological Sciences, who said: "Toxins secreted by algae, and which concentrate in shellfish, are a major hazard to consumers and can bring huge economic losses to the aquaculture industry.

"While the existence of these toxins has been known for some time, there have been major concerns about the effectiveness of tests used to detect them. There is also growing evidence that climate change is causing a number of more toxic episodes across the world, resulting in the closure of affected shellfish beds......... Posted by: Kelly      Read more         Source

January 10, 2011, 6:29 AM CT

Ginger for conserving stag beetles

The humble ginger root could be the key to conserving the UK's largest and most spectacular terrestrial beetle � the stag beetle. Ecologists from Royal Holloway, University of London and the University of York have developed a series of new methods to monitor stag beetle numbers � including ginger lures to trap adult beetles and tiny microphones to detect sounds made by the larvae in their underground nests. Conservation efforts have been hampered until now because ecologists lacked a reliable way of monitoring stag beetle numbers.

The new research, reported in the Royal Entomological Society's journal Insect Conservation and Diversity, observed that a combination of ginger-baited aerial traps to catch adult stag beetles, plus tiny microphones to record the underground larvae's sounds and samplers to detect the chemicals they emit, give an accurate picture of the species' abundance.

As per Dr Deborah Harvey, one of the study's authors: "Our new methods offer genuine promise for monitoring the population of this elusive and rare insect, one that we think is declining across much of its European range. We need to know where the stag beetle lives � and in what numbers � to be able to conserve it effectively".

Harvey and her colleagues discovered ginger was irresistible to adult stag beetles only after testing the attractiveness of a number of other fruit and vegetables � including banana, strawberry, tomato and cherry � as well as wine and beer. Ginger works because it contains large amounts of alpha copaene, a chemical known to attract other insects that live in dead and decaying wood......... Posted by: Kelly      Read more         Source

January 10, 2011, 6:21 AM CT

Wildflower colors tell butterflies how to do their jobs

The recipe for making one species into two requires time and some kind of separation, like being on different islands or something else that discourages gene flow between the two budding species.

In the case of common Texas wildflowers that share meadows and roadside ditches, color-coding apparently does the trick.

Duke University graduate student Robin Hopkins has found the first evidence of a specific genetic change that helps two closely related wildflowers avoid creating costly hybrids. It results in one of the normally light blue flowers being tagged with a reddish color to appear less appetizing to the pollinating butterflies which prefer blue.

"There are big questions about evolution that are addressed by flower color," said Hopkins, who successfully defended her doctoral dissertation just weeks before seeing the same work appear in the prestigious journal Nature

What Hopkins found, with her thesis adviser, Duke biology professor Mark Rausher, is the first clear genetic evidence for something called reinforcement in plants. Reinforcement keeps two similar proto-species moving apart by discouraging hybrid matings. Flower color had been expected to aid reinforcement, but the genes had not been found.

In animals or insects, reinforcement might be accomplished by a small difference in scent, plumage or mating rituals. But plants don't dance or choose their mates. So they apparently exert some choice by using color to discourage the butterflies from mingling their pollen, Hopkins said......... Posted by: Kelly      Read more         Source

January 7, 2011, 6:56 AM CT

Statistical Analysis for Crop Performance

Researchers at Rothamsted Research, United Kingdom, in collaboration with the International Center for Agriculture Research in the Dry Areas (ICARDA), Syria have developed a method of accounting for spatial trend in single crop field trials. Spatial trend refers to the variations in crop yield and other characteristics observed when repeating this single crop field trial.

Commonly plant breeders will grow several replicate plots to assess the breed line in different environments and then compare the results to commercial or standard varieties of the crop. When resources or seed are scarce, breeders will grow only a single plot of a test line alongside many other standard varieties acting as check plots.

"The results have shown that adjustment for spatial trend within the trials is possible and gives improved accuracy on the estimates of line performance," says Sue Welham, one of the authors of the study.

A crop developed by Dr. Miloudi Nachit at ICARDA was used to illustrate spatial trend in this particular experimental design. The teams then used simulations to further demonstrate the dramatic increase in precision in estimating the performance of a line while adjusting for spatial trend. However, these measurements are not without their flaws.

As per Welham, "One drawback to the use of spatial adjustment is the possible subjectivity and difficulty in the choice of a model"......... Posted by: Erica      Read more         Source

January 6, 2011, 6:13 PM CT

Biofuel grasslands better for birds

Developing biofuel from native perennials instead of corn in the Midwest's rolling grasslands would better protect threatened bird populations, Michigan State University research suggests.

Federal mandates and market forces both are expected to promote rising biofuel production, MSU biologist Bruce Robertson says, but the environmental consequences of turning more acreage over to row crops for fuel are a serious concern.

Ethanol in America is chiefly made from corn, but research is focusing on how to cost-effectively process cellulosic sources such as wood, corn stalks and grasses. Perennial grasses promise low cost and energy inputs - planting, fertilizing, watering - and the newly released study quantifies substantial environmental benefits.

"Native perennial grasses might provide an opportunity to produce biomass in ways that are compatible with the conservation of biodiversity and important ecosystem services such as pest control," Robertson said. "This work demonstrates that next-generation biofuel crops have potential to provide a new source of habitat for a threatened group of birds".

With its rich variety of ecosystems, including historic prairie, southern Michigan provided a convenient place to compare bird populations in 20 sites of varying size for each of the three fuel feedstocks. Grassland birds are of special concern, Robertson said, having suffered more dramatic population losses than any other group of North American birds......... Posted by: Kelly      Read more         Source

January 5, 2011, 6:50 AM CT

Making plant breeding easier

University of Illinois research has resulted in the development of a novel and widely applicable molecular tool that can serve as a road map for making plant breeding easier to understand. Scientists developed a unified nomenclature for male fertility restorer (RF) proteins in higher plants that can make rapid advancements in plant breeding.

"Understanding the mechanism by which RF genes suppress the male sterile phenotype and restore fertility to plants is critical for continued improvements in hybrid technology," said Manfredo J. Seufferheld, U of I assistant professor of crop sciences.

To reach this goal, Seufferheld teamed up with post-doctoral scientists Simeon O. Kotchoni and Emma W. Gachomo of Purdue University, and Jose C. Jimenez-Lopez of the Estacion Experimental del Zaidin, Consejo Superior de Investigaciones Cientificas (CSIC) in Granada, Spain, to develop a simplified genetic-based nomenclature that automatically catalogues the entire RF gene products into families and subfamilies.

"Up to now, there has been no unified nomenclature for naming the RF proteins," Seufferheld said. "As the systematic sequencing of new plant species has increased in recent years, naming has been simply arbitrary. We have had 'chaos' in the databases. The RF information in the databases could not be adequately handled in the context of comparative functional genomics"......... Posted by: Erica      Read more         Source