Home Animal science blog Plant science blog Biology blog

Plant Science Blog

Subscribe To Plant Science Blog RSS Feed  RSS content feed What is RSS feed?

August 4, 2011, 8:22 AM CT

Effects of Rising Carbon Dioxide on Rangelands

Effects of Rising Carbon Dioxide on Rangelands
ARS plant physiologist Jack Morgan is leader of a group replicating anticipated higher carbon dioxide and temperature levels to study their impact on semi-arid rangeland grasses.
Rising carbon dioxide (CO2) levels can reverse the drying effects of predicted higher temperatures on semi-arid rangelands, as per a research studypublished recently in the scientific journal Nature by a team of U.S. Department of Agriculture (USDA) and university scientists.

Warmer temperatures increase water loss to the atmosphere, leading to drier soils. In contrast, higher CO2 levels cause leaf stomatal pores to partly close, lessening the amount of water vapor that escapes and the amount of water plants draw from soil. This newly released study finds that CO2 does more to counterbalance warming-induced water loss than previously expected. In fact, simulations of levels of warming and CO2 predicted for later this century demonstrated no net change in soil water, and actually increased levels of plant growth for warm-season grasses.

"By combining higher temperatures with elevated CO2 levels in an experiment on actual rangeland, these scientists are in the process of developing the scientific knowledge base to help prepare managers of the world's rangelands for what is likely to happen as climate changes in the future," said Edward B. Knipling, administrator of the Agricultural Research Service (ARS), USDA's principal intramural scientific research agency.........

Posted by: Erica      Read more         Source


July 5, 2011, 8:56 PM CT

Cool-season grasses more profitable than warm-season grasses

Cool-season grasses more profitable than warm-season grasses
Access to swine effluent or waste water can help a producer grow more grass. But a Texas AgriLife Researcher says the grass is "greener" economically if it is a cool-season rather than a warm-season variety.

Dr. Seong Park, AgriLife Research economist in Vernon, said while the warm-season grasses appear to have a greater growth boost with swine effluent application, the cool-season grasses have marketing advantages that make it a more viable economic option for producers in the Oklahoma Panhandle and Southern Plains.

Park recently had the results of his study reported in the Journal of American Society of Farm Manager and Rural Appraisal. The study was funded by a U.S. Department of Agriculture grant for "Comprehensive Animal Waste Systems in Semiarid Ecosystems." Cooperators in the study were Dr. Jeffrey Vitale and Dr. Jeffory Hattey, both with Oklahoma State University.

The study reviewed the risk and economics of intensive forage production systems under four alternative types of forage and two alternative nitrogen sources, he said. The results will help farmers make better informed production decisions.

The study compared two cool-season grasses � orchard grass and wheatgrass � with two warm-season grasses � Bermuda grass and buffalo grass, he said. The two nitrogen sources used to fertilize the crop were urea or swine effluent.........

Posted by: Erica      Read more         Source


June 21, 2011, 11:39 PM CT

New not-so-sweet potato resists pests and disease

New not-so-sweet potato resists pests and disease
Scientists from Clemson University and the USDA Agricultural Research Service have developed a new variety of not-so-sweet potato, called Liberty.
image by: Clemson University
Researchers from Clemson University and the USDA Agricultural Research Service have developed a new variety of not-so-sweet potato, called Liberty.

Known as a boniato, or tropical sweet potato, Liberty has a dark red skin and light yellow, dry flesh with a bland flavor. Boniato potatoes originated in the tropical Americas and are grown in south Florida in the United States. They can be served fried, mashed or in soup.

"We developed Liberty because other boniato varieties are susceptible to damage by nematodes (microscopic parasitic worms)," said John Mueller, plant pathologist and director of Clemson's Edisto Research and Education Center in Blackville.

Mueller worked with a team of researchers from the U.S. Vegetable Laboratory in Charleston led by entomologist Mike Jackson. Other USDA Agricultural Research Service team members included agronomist Howard Harrison, plant pathologist Judy Thies and plant geneticist Janice Bohac.

The Liberty potato is highly resistant to nematodes and moderately resistant to insect pests and fusarium wilt, a fungal disease. Liberty potatoes have good baking quality, store well and do not darken after peeling as most boniato potatoes do. Home gardeners, as well as commercial producers and organic growers, can grow the Liberty potato.........

Posted by: Erica      Read more         Source


April 1, 2011, 7:32 AM CT

Sun and shade leaves play different roles in tree canopies

Sun and shade leaves play different roles in tree canopies
'Outer' tree canopy leaves influence the sunlight reaching inner canopy leaves by changing their shape, says a newly released study.

The shape and physiology of leaves within the tree canopy is not constant, and can vary depending on their position within the tree crown. This phenomenon is expected to have important consequences for how trees cope with stress and use resources.

A newly released study describes how the leaves in the outer canopy of olive trees can influence the light environment within the canopy by changing their shape, as more elongated leaves resulted in higher levels of solar radiation inside the crown.

Author Rafael Rubio de Casas and his colleagues found that inner canopy leaves appear to be especially adapted to the use of diffuse solar radiation, which is more constant than direct radiation. They propose that outer canopy leaves change not only to maximize their own performance, but also to create a beneficial environment for the inner canopy leaves. They also suggest that leaves in various positions of the canopy can use different types of solar radiation for photosynthesis and operate at different time windows. Exposed leaves are expected to use direct solar radiation and be more active when the sun is close to the horizon, while shaded leaves specialize in the capture of diffuse radiation and are more active when the sun is higher.........

Posted by: Erica      Read more         Source


March 26, 2011, 10:16 PM CT

stranglers of the tropics

stranglers of the tropics
Credit: National Science Foundation

Kudzu, the plant scourge of the U.S. Southeast. The long tendrils of this woody vine, or liana, are on the move north with a warming climate.

But kudzu appears to be no match for the lianas of the tropics, researchers have found. Data from sites in eight studies show that lianas are overgrowing trees in every instance.

If the trend continues, these "stranglers-of-the-tropics" may suffocate equatorial forest ecosystems.

Tropical forests contain more than half of Earth's terrestrial species, and contribute more than a third of global terrestrial carbon and a third of terrestrial net primary productivity, says ecologist Stefan Schnitzer of the University of Wisconsin-Milwaukee.

Schnitzer is co-author with Frans Bongers of Wageningen University in the Netherlands of a paper on lianas in the current issue of the journal Ecology Letters.

"Any alteration of tropical forests has important ramifications for species diversity, productivity--and ultimately the global carbon cycle," says Schnitzer.

Tropical forests are indeed experiencing large-scale structural changes, the most obvious of which appears to be the increase in lianas, as per Robert Sanford, an NSF program director. The research was funded by the National Science Foundation (NSF)'s Division of Environmental Biology.........

Posted by: Erica      Read more         Source


March 18, 2011, 6:23 PM CT

Pollen also appears outside flowering season

Pollen also appears outside flowering season
A pollen trap.

Credit: AeroUEx

"There is of course a very close relationship between the moment at which pollen is released by plants and the data gathered by the traps used to measure these grains, but this is not always the case", Rafael Tormo, a botanist from the University of Extremadura and co-author of the paper, tells SINC.

His team found delays or advances of up to a week between the time when the pollen of allergenic grass species (from genuses such as Poa, Agrostis, Bromus and Avena) and cupressaceae (cypresses and Arizona pine) are present in the air and their flowering period.

As per the study, which has been reported in the International Journal of Biometeorology, these differences are probably due to the phenomenon of "resuspension" of the grains, caused by the wind and by pollen being transported from distant sources.

"Now, for example, the Holm oaks in Extremadura have not yet flowered, but those in Andalusia have done. If the wind blows from the south, the pollen traps in Extremadura will already be able to detect Holm oak pollen", explains Tormo, who highlights the importance of understanding the phenology of plant flowering in order to draw up precise pollen prognoses for people with allergies.

On the Iberian Peninsula and in the rest of Europe, the process of flowering moves from south to north, in such a way that the pollen traps "anticipate flowering" if the wind blows from the south. Conversely, if the wind blows from the north they may record pollen from more northerly latitudes even if the pollination period in the region they are located in is already over.........

Posted by: Erica      Read more         Source


March 17, 2011, 11:05 PM CT

Optimizing yield and fruit size of figs

Optimizing yield and fruit size of figs
This is a photo showing Breba figs developing on one-year-old shoots.

Credit: Photo by Hein Gerber

The common fig is a subtropical, deciduous fruit tree grown in most Mediterranean-type climates. Eventhough some think that figs appears to be the oldest cultivated fruit species on earth, global expansion of fig crops has been hindered by the narrow research base pertaining to production practices and the limited number of fig cultivars currently available. Recently, three black figs were established in the Mediterranean-type climate of Western Cape Province of South Africa to provide fruit for fresh markets throughout South Africa and Europe.

Hein J. Gerber, Willem J. Steyn, and Karen I. Theron from the Department of Horticultural Science at South Africa's University of Stellenbosch reported on a study they conducted on three fig cultivars in HortScience. The research, conducted as part of Gerber's MScAgric degree requirements, was developed to establish the optimum 1-year-old shoot length to maximize fig fruit yield and quality.

"To maximize yield of good-quality fruit, the most productive shoot lengths (in terms of yield and fruit size) should be determined and strategies devised to maximize the number of these shoots on trees on an annual basis. It is important to study the phenological characteristics of a cultivar to establish optimum shoot characteristics", said Theron, corresponding author of the study. "The objective of our research was to identify the most suitable types of shoots and complete a detailed, comparative study of processes such as budbreak, shoot growth, and yield for each shoot length category".........

Posted by: Erica      Read more         Source


March 17, 2011, 10:53 PM CT

Multimedia in nursery management

Multimedia in nursery management
Instructional multimedia can be effectively used to create virtual field trips in a variety of horticulture-related classes.

Credit: Photo courtesy of Amy N. Wright

Students at land-grant universities are a major source of educated, highly qualified employees for the U.S. nursery industry. To prepare future employees for work in "green" occupations, land-grant institutions have traditionally offered classes in nursery management and production, but availability of qualified faculty, integration of departments, and cutbacks in horticulture programs have contributed to a reduction in the number of nursery management and production (NMP) courses being offered.

In a recent issue of HortTechnology, Amy N. Wright, James A. Robbins, and Mengmeng Gu report on an online survey they designed to gather information about nursery management and production (NMP) course content and enrollment, attitudes regarding the use of multimedia resources in the classroom, and opinions about the use of virtual field trips to supplement or replace traditional field trips.

To find out more about current practices in NMP, a survey was sent to instructors of courses that cover topics in NMP at 97 institutions in the U.S. As per Wright, corresponding author of the study; "Results reflected current organizational and curriculum changes that have impacted traditional horticulture courses such as NMP and in a number of cases have resulted in the merging of NMP courses with other courses such as greenhouse or garden center management." Most of the respondents indicated that the NMP course in their department included at least one field trip.........

Posted by: Erica      Read more         Source


March 15, 2011, 10:39 PM CT

Dairy Farmer fInds Unusual Forage Grass

Dairy Farmer fInds Unusual Forage Grass
A U.S. Department of Agriculture (USDA) grass breeder has rediscovered a forage grass that seems just right for today's intensive rotational grazing.

A farmer's report of an unusual forage grass led Michael Casler, an Agricultural Research Service (ARS) geneticist at the agency's U.S. Dairy Forage Research Center in Madison, Wis., to identify the grass as meadow fescue. Meadow fescue has been long forgotten, eventhough it was popular after being introduced about 50 to 60 years before tall fescue.

ARS is USDA's principal intramural scientific research agency.

Casler has developed a new variety of meadow fescue called Hidden Valley, and its seed is being grown for future release.

Non-toxic fungi called endophytes live inside meadow fescue, helping it survive heat, drought and pests. Unlike the toxic endophytes that inhabit a number of commercial varieties of tall fescue and ryegrass, meadow fescue does not poison livestock.

Charles Opitz found the grass growing in the deep shade of a remnant oak savannah on his dairy farm near Mineral Point, Wis. He reported that the cows love it and produce more milk when they eat it. Casler used DNA markers to identify Opitz's find.

Meadow fescue is very winter-hardy and persistent, having survived decades of farming. It emerged from oak savannah refuges to dominate a number of pastures in the Midwest's driftless region, named for its lack of glacial drift, the material left behind by retreating continental glaciers.........

Posted by: Kelly      Read more         Source


February 14, 2011, 6:48 AM CT

Vines overtaking the American tropics

Vines overtaking the American tropics
Sleeping Beauty's kingdom was overgrown by vines when she fell into a deep sleep. Scientists at the Smithsonian in Panama and the University of Wisconsin at Milwaukee received more than a million dollars from the U.S. National Science Foundation to discover why real vines are overtaking the American tropics. Data from eight sites show that vines are overgrowing trees in all cases.

"We are witnessing a fundamental structural change in the physical make-up of forests that will have a profound impact on the animals, human communities and businesses that depend on them for their livelihoods," said Stefan Schnitzer, research associate at the Smithsonian Tropical Research Institute in Panama and associate professor at the University of Wisconsin at Milwaukee.

Tropical forests hold more than half of the Earth's terrestrial species and much of the planet's carbon. If vines take over tropical forests the rules used to model ecosystem services, such as regulation of the water cycle and carbon storage may no longer apply.

"In 2002, Oliver Phillips, a professor at the University of Leeds in the U.K., published a controversial study claiming that vines were becoming more common in the Amazon," said Schnitzer. "By pulling together data from eight different studies, we now have irrefutable evidence that vines are on the rise not only in the Amazon, but throughout the American tropics".........

Posted by: Erica      Read more         Source


February 8, 2011, 6:50 AM CT

New findings in India's Bt cotton controversy

New findings in India's Bt cotton controversy
Crop yields from India's first genetically modified crop may have been overemphasized, as modest rises in crop yields may come at the expense of sustainable farm management, says a newly released study by a Washington University in St. Louis anthropologist.

The study, by Glenn Stone, PhD, professor of anthropology in Arts & Sciences, appears in the recent issue of the journal World Development.

In his paper, Stone compares village yields in 2003 and 2007, which conveniently had very similar levels of rainfall. "Cotton yields rose 18 percent with the adoption of genetically modified seeds," Stone says. "This is less than what has been reported in some economics studies, but much better than activists have claimed".

Pesticide sprayings also were down by 55 percent with the switch to genetically modified seed.

The crop in question is Bt cotton, genetically modified to produce its own insecticide. Approved for Indian farmers since 2002, the technology is being closely watched because it is the most widely planted GM crop on small farms in the developing world.

A number of activists and commentators, including England's Prince Charles, have accused Bt cotton of failing, ruining small farmers and causing suicides, Stone claims.

Several studies by economists, however, have shown Bt cotton farmers to be getting higher yields when compared with planters of conventional cotton.........

Posted by: Erica      Read more         Source


February 8, 2011, 6:39 AM CT

Phosphorus: Too Much or Too Little?

Phosphorus: Too Much or Too Little?
Fertilizer is rarely an inspiration for an art show, but this week at Arizona State University (ASU), sustainability, fertilizer and phosphorus scarcity will provide fuel for creative vision.

The art show, a juried exhibition with works by artists from Phoenix, Chicago, Portland and Houston, was created in partnership with researchers engaged in the Sustainable Phosphorus Summit, to take place Feb. 3-5, 2011, at ASU.

The summit is funded by the National Science Foundation (NSF).

Phosphate is a type of salt, which is mined for use in industry and as a fertilizer in agriculture.  It is an essential nutrient for life. Without it, people cannot grow food or build bones.

"We need to be concerned about the emerging threat of phosphorus scarcity, as well as the impacts of too much phosphorus through run-off into lakes and oceans," says Matt Kane, program director in NSF's Division of Environmental Biology, which supports the phosphorus summit.

Human activities have increased bioavailable phosphorus in the environment, or phosphorus from runoff, by some 400 percent, but the demand for it continues to increase. Meanwhile, phosphate available in mines--the only viable source--is on the decline.

The summit will explore phosphorus as a limited resource. It will bring together international experts to discuss issues ranging from the biological importance of phosphorus to concerns about national security.........

Posted by: Erica      Read more         Source


February 2, 2011, 7:59 AM CT

Technology protects cotton from caterpillar's appetite

Technology protects cotton from caterpillar's appetite
Aerial photographs show that while the genetically modified crop survived intact, the unprotected plants were destroyed by the caterpillars.
image by: Jeremy Greene
The furry-looking insects start their development smaller than the head of a pin, but the caterpillars soon develop an appetite for cotton as big as the crop.

To demonstrate the insects' destructive power, Clemson University entomologist Jeremy Greene planted two cotton varieties - one genetically modified to provide protection from caterpillars, one not - in a demonstration field at the Edisto Research and Education Center.

The non-protected cotton was planted in a pattern that spelled the word "Tigers." Aerial photographs taken near harvest show that while the genetically modified crop survived intact, the unprotected plants provided three square meals a day for the crop-hungry herbivores.

The demonstration crop was planted in late May last year and grew through the summer.

"We wanted to show the kind of damage caterpillars can do when they're allowed to eat unprotected cotton freely," Greene said.

Cotton is a multimillion dollar crop in the Palmetto State involving hundreds of farms and thousands of jobs.

Nearly all cotton varieties planted in South Carolina contain genes found in the naturally occurring Bacillus thuringiensis, or Bt, that help the plant make its own insecticide.

Bt cotton is genetically modified with specific genes from Bacillus thuringiensis. Think of it as in-plant insecticide, Greene said. This technology has been commercially available since 1996, but improvements over the years have enhanced the control of major pests.........

Posted by: Erica      Read more         Source


February 2, 2011, 7:52 AM CT

Home and Away: Are Invasive Plant Species Really That Special?

Home and Away: Are Invasive Plant Species Really That Special?
Invasive plant species are a serious environmental, economic and social problem worldwide. Their abundance can lead to lost native biodiversity and ecosystem functions, such as nutrient cycling.

Despite substantial research, however, little is known about why some species dominate new habitats over native plants that technically should have the advantage.

A common but rarely tested assumption, say biologists, is that these plants behave in a special way, making them more abundant when introduced into communities versus native plants that are already there.

If true, it would mean that biosecurity screening procedures need to address how species will behave once introduced to nonnative communities--very difficult to get right, scientists have found.

Researchers in a global collaboration called the Nutrient Network tested this "abundance assumption" for 26 plant species at 39 locations on four continents and found numerous problems with it.

The results are published in a paper in the current issue of the journal Ecology Letters

"Predicting success of invading species is difficult and uncertain, but very important," says Henry Gholz, program director in the National Science Foundation (NSF)'s Division of Environmental Biology, which funds the Nutrient Network.........

Posted by: Erica      Read more         Source


Sun, 30 Jan 2011 17:07:33 GMT

Kalanchoe fedtschenkoi

Kalanchoe fedtschenkoi
Another entry from Claire today. She writes:

This photograph of Kalanchoe fedtschenkoi was taken at the Rutgers Floriculture Greenhouse by Elena (mycologie@Flickr) and provided to us via the BPotD Flickr Pool. Much appreciated, Elena!

Kalanchoe fedtschenkoi belongs to a family of succulent herbaceous species and soft-stemmed shrubs, the Crassulaceae. Crassulaceae has about 34 genera and 1370 species spread over a wide range of the world (frequently in drier regions). This family is known for CAM photosynthesis, which they and many other groups of taxa utilize. CAM is an acronym for Crassulacean Acid Metabolism, an adaptive strategy to allow maximum water storage.

This beautiful species is a native of Madagascar, but is widely cultivated as an ornamental and houseplant. As it is a succulent, it requires little water and is very low maintenance. Kalanchoe fedtschenkoi easily establishes and can take root from even one leaf being transplanted (it has escaped cultivation and become invasive in some subtropical places).

The common name is lavender scallop, due to the slightly purplish/pinkish tinge of the leaves. Some pictures of the vegetative parts can be found on the University of Connecticut"s Ecology & Evolutionary Biology Greenhouses site: Kalanchoe fedtschenkoi.

Posted by: Daniel Mosquin      Read more     Source


January 28, 2011, 7:09 AM CT

Call for regulation of rare plant sales

Call for regulation of rare plant sales
eople are increasingly obtaining endangered or threatened plants, often illegally, and moving them outside their native range, as per an article in the journal Nature by Patrick Shirey and Gary Lamberti in the department of biological sciences at the University of Notre Dame.

As per their research last year, nearly 10 percent of the 753 plants listed as threatened and endangered under the US Endangered Species Act are being sold � or, at least, advertised � online. A number of buyers are horticulturalists who want flowers for their gardens. But increasingly, anecdotal evidence suggests that online shoppers include individuals and citizen groups involved in 'assisted colonization' projects. Here, species or genetic subtypes at risk of extinction are moved to non-native environments in which they might thrive � in the face of climate change, for instance.

Some private groups who want to protect the plants, such as the Torreya Guardians, are legally planting seedlings of the Florida torreya outside its current range to aid species conservation. However, Shirey urges government agencies to take more of a leadership role to monitor translocations because of the risks linked to introducing new species. The widespread transfer of endangered or threatened plants poses both environmental and economic risks.........

Posted by: Erica      Read more         Source


January 25, 2011, 7:29 AM CT

Wheat resistance genes failing

Wheat resistance genes failing
Wheat with resistance genes (left) shows little damage from Hessian flies, while a non-resistant variety (right) has been largely destroyed. (Photo courtesy of Dr. Michael Boyd, University of Missouri)

A number of of the genes that allow wheat to ward off Hessian flies are no longer effective in the southeastern United States, and care should be taken to ensure that resistance genes that so far haven't been utilized in commercial wheat lines are used prudently, as per U.S. Department of Agriculture and Purdue University scientists.

An analysis of wheat lines carrying resistance genes from dozens of locations throughout the Southeast showed that some give little or no resistance to the Hessian fly, a major pest of wheat that can cause millions of dollars in damage to wheat crops each year. Others, even those considered the most effective, are allowing wheat to become susceptible to the fly larvae, which feed on and kill the plants.

Wheat resistance genes recognize avirulent Hessian flies and activate a defense response that kills the fly larvae attacking the plant. However, this leads to strains of the fly that can overcome resistant wheat, much like insects becoming resistant to pesticides.

"The number of genes available to protect wheat is limited. There really aren't that a number of," said Richard Shukle, a research scientist with the USDA Agricultural Research Service Crop Production and Pest Control Research Unit and Purdue adjunct associate professor of entomology. "In the Southeast, having multiple generations of Hessian fly each year enhances the ability of these flies to overcome wheat's resistance".........

Posted by: Erica      Read more         Source


January 21, 2011, 10:21 PM CT

How isolated are mountain top plant populations?

How isolated are mountain top plant populations?
This is Penstemon pachyphyllus and a bumblebee.

Credit: Courtesy of Andrea Kramer, Chicago Botanic Garden.

Do mountain tops act as sky islands for species that live at high elevations? Are plant populations on these mountain tops isolated from one another because the valleys between them act as barriers, or can pollinators act as bridges allowing genes to flow among distant populations?

Dr. Andrea Kramer and his colleagues from the Chicago Botanic Garden and the University of Illinois at Chicago were interested in pursuing these questions, especially for a genus of plants, Penstemon (Plantaginaceae), endemic to the Great Basin region of the Western United States. They published their findings in the recent issue of the American Journal of Botany (http://www.amjbot.org/cgi/content/full/98/1/109).

The flow of genetic material between populations maintains a species. In plants, if populations are separated by a landscape barrier such that pollen or seeds are unable to traverse either over or through, then the populations will begin to differ, either via mutations or genetic drift over time. However, habitat fragmentation and distance may not always be barriers, depending on the species and their modes of dispersal. And sometimes studies surprise us with their findings.

"These questions become increasingly important in places like the Great Basin as we consider the effects of climate change on native plant communities and the wildlife that depend upon them," Kramer commented. "The majority of the Great Basin region's species diversity is located on mountain tops, and as a generally warming climate drives species to higher elevations, the distance between mountaintop plant populations increases and more is mandatory of the pollinators in order to traverse the arid valleys between them."........

Posted by: Erica      Read more         Source


January 16, 2011, 10:11 PM CT

New software quantifies leaf venation networks

New software quantifies leaf venation networks
This is a screenshot of the LEAF GUI software. Images to the right of the original and modified images correspond to the region contained within the zoom rectangle shown on the original image.

Credit: Copyright American Society of Plant Biologists; dx.doi.org/10.1104/pp.110.162834

Plant biologists are facing pressure to quantify the response of plants to changing environments and to breed plants that can respond to such changes. One method of monitoring the response of plants to different environments is by studying their vein network patterns. These networks impact whole plant photosynthesis and the mechanical properties of leaves, and vary between species that have evolved or have been bred under different environmental conditions.

To help address the challenge of how to quickly examine a large quantity of leaves, scientists at the Georgia Institute of Technology have developed a user-assisted software tool that extracts macroscopic vein structures directly from leaf images.

"The software can be used to help identify genes responsible for key leaf venation network traits and to test ecological and evolutionary hypotheses regarding the structure and function of leaf venation networks," said Joshua Weitz, an assistant professor in the Georgia Tech School of Biology.

The program, called Leaf Extraction and Analysis Framework Graphical User Interface (LEAF GUI), enables researchers and breeders to measure the properties of thousands of veins much more quickly than manual image analysis tools.

Details of the LEAF GUI software program were reported in the "Breakthrough Technologies" section of the recent issue of the journal Plant Physiology Development of the software, which is available for download at www.leafgui.org, was supported by the Defense Advanced Research Projects Agency (DARPA) and the Burroughs Welcome Fund.........

Posted by: Erica      Read more         Source


January 16, 2011, 9:18 PM CT

Heavy metals and pesticides threaten

Heavy metals and pesticides threaten
cultivation of strawberries in the affected area to wetland Domingo Rubio.

Credit: Barba-Brioso et al.

The Estero de Domingo Rubio wetland, located near the Marismas del Odiel Natural Area in the Huelva estuary, is regionally, nationally and internationally protected thanks to its ecological value. However, its tributary rivers and the R�a de Huelva estuary pump manmade pollutants into it, which could affect its water quality and ecosystem.

Industrial activity, accumulations of dangerous waste, the expansion of farming, and excessive extraction of sand and gravel for the construction industry are the leading threats to the Estero de Domingo Rubio wetland, the tidal system of which plays a "crucial" role in transporting and dispersing pollutants.

The wetland is "periodically flooded with high levels of dissolved elements such as copper (Cu), arsenic (As), cadmium (Cd), cobalt (Co), chrome (Cr), nickel (Ni) and zinc (Zn), which come from the water entering the estuary, which is affected by pollution from the mining industry", Cinta Barba-Brioso, co-author of the study and a researcher at the University of Seville (US), tells SINC.

The study, which has recently been reported in the Marine Pollution Bulletin, shows that the wetland's tidal channel also receives acid lixiviates (liquid pollutants) that come from the dumping of sulphurous waste, industrial waste outflow pipes, and abandoned chemical plants, which all contribute to its metallic "enrichment".........

Posted by: Erica      Read more         Source


January 16, 2011, 8:56 PM CT

Green Super Rice is coming

Green Super Rice is coming
Rice bred to perform well in the toughest conditions where the poorest farmers grow rice is a step away from reaching farmers thanks to a major project led by the Chinese Academy of Agricultural Sciences and the International Rice Research Institute (IRRI).

Green Super Rice is actually a mix of more than 250 different potential rice varieties and hybrids variously adapted to difficult growing conditions such as drought and low inputs, including no pesticide and less fertilizer, and with rapid establishment rates to out-compete weeds, thus reducing the need for herbicides. More types of Green Super Rice that combine a number of of these traits are in the pipeline.

As published in the latest issue of Rice Today, Green Super Rice is already in the hands of national agricultural agencies in key rice-growing countries for testing and development.

Green Super Rice is an example of what is needed as part of a "Greener Revolution," which is called for by rice researchers around the world and is one of the driving concepts behind the Global Rice Science Partnership (GRiSP) - a plan to improve international partnerships in rice research, its delivery, and impact that would also ensure that rice is grown in an environmentally sustainable way.

With the theme Rice for Future Generations, the 3rd International Rice Congress held in November last year was the perfect venue for the launch of GRiSP. Incredible sharing of rice research and ideas occurred, which Rice Today features in a suite of stories outlining some of the highlights and activities of the event that was attended by more than 1,900 people.........

Posted by: Erica      Read more         Source


Mon, 17 Jan 2011 01:03:27 GMT

Parnassia fimbriata

Parnassia fimbriata
A bit of BPotD news before today"s entry: we finally have a date and time set to transition the web site over to the new server. It"s been a real headache for months, but hopefully the pain will be over by mid-week next week. On Monday @ 10am local time, we"ll start to move the site over. Unfortunately, since we"re also moving to a new server, the web site domain name needs to be pointed to the new server, and that means it may be a couple days before you are able to access content on the new site while the name propagates to the various Internet Service Providers. The old site will still be running for a few days, but comments will be turned off. Fingers crossed that all goes well!

The last time I featured a Parnassia on BPotD (over 5 years ago: Parnassia glauca), I wrote that the genus had been moved out of the Saxifragaceae (you"ll see that in many classification systems) and even out of the Saxifragales (the order containing the Saxifragaceae and related families) and into the Parnassiaceae (within the Celastrales). A number of research groups have since studied the relationships between Parnassiaceae and Celastraceae; current thought provisionally places Parnassia within the Celastraceae, but it seems (after reading the Phylogeny section on the linked page) that this may yet revert to being split again.

This August photograph of Parnassia fimbriata (fringed grass-of-Parnassus or Rocky Mountain grass-of-Parnassus) was taken only meters away from a second of British Columbia"s four Parnassia species, Parnassia kotzebuei. Parnassia is another genus I am always thrilled to encounter, as it was one of the first dozen or so I learned to recognize in Manitoba.

Parnassia fimbriata is native to much of western North America, where it grows in moist sites (fens, bogs, streamside, seeps, wet meadows) at elevations ranging from lowland to alpine. It is the tallest of these herbaceous species in British Columbia, occasionally reaching 50cm in height (though more typically 15 to 30cm). Parnassia kotzebuei, by comparison, is the shortest, ranging from 6-20cm.

Parnassia is a reference to Mount Parnassus; Linnaeus applied the name to the genus based on an account in Materia Medica, a written work by the Greek physician Dioscorides (Dioscorides called it Agrostis En Parnasso). The Plants for a Future database contains a listing of historical medicinal uses for Parnassia palustris, the species thought to have been described by Dioscorides (who also said of it: "That which grows in Cilicia (which the inhabitants call cinna) inflames rude beasts if often fed on when it is moist".

For additional photographs, see Calphotos: Parnassia fimbriata or Southwest Colorado Wildflowers: Parnassia fimbriata.

Posted by: Daniel Mosquin      Read more     Source


January 11, 2011, 6:54 AM CT

Strawberry Genome Sequence Promises Better Berries

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

Miscanthus has a fighting chance against weeds
Miscanthus is a perennial grass being investigated at the University of Illinois in Urbana-Champaign as a cellulosic bioenergy feedstock, pictured here beside switchgrass, a native prairie grass.

Credit: Eric Anderson, University of Illinois

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 10, 2011, 6:21 AM CT

Wildflower colors tell butterflies how to do their jobs

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


Mon, 10 Jan 2011 04:06:14 GMT

The Color Orange Was Named After The Fruit

The Color Orange Was Named After The Fruit
The color orange was named after the fruit, not the other way around. Before then, the English speaking world referred to the orange color as geoluhread, which literally translates to "yellow-red." The word orange itself was introduced to English through the Spanish word "naranja," which came from the Sanskrit word nāraga, which literally means "orange tree."

In the early 16th century, the word orange gradually started being used to not only refer to the fruit, but also what we now know of as the color orange.

Posted by: Gerard      Read more     Source


Mon, 10 Jan 2011 03:30:51 GMT

Thevetia peruviana

Thevetia peruviana
Today"s entry was written by Claire:

This photograph of Thevetia peruviana was taken by Qamar Mehdi (S.Q. Medhi@Flickr) of Lahore, Pakistan and provided via the Botany Photo of the Day Flickr Pool. Thank you Qamar!

Apocynaceae includes over 4500 species, with the highest diversity in tropical and subtropical regions (though there are temperate representatives as well). Thevetia peruviana is among the subtropicals. Probably native to Mexico, it has naturalized in much of the neotropics. It is also widely cultivated throughout all tropical regions, where it tends to bloom year-round. This shrub"s flowers range from the lovely apricot colour seen in Qamar"s photograph to coral, yellow, white, and even tan.

A glance at the leaves might remind of oleander (Nerium oleander). In fact, it is sometimes called yellow oleander, and the species are close relatives. Both are evergreen shrubs and have five petals arranged in an attractive whorl. Also like oleander, Thevetia peruviana is extremely toxic in all parts of the plant, containing cardiac glycosides (toxins poisonous to most vertebrates). Several bird species are known to be resistant to the toxins, including the Asian koel, bulbul, myna, and the common grey hornbill. For those animals not resistant to the poisons, the toxic effects include unpleasant cardiac and gastrointestinal symptoms (that I shouldn"t list here) when ingested. To give an idea of its strength, though, the International Programme on Chemical Safety cites a report with respect to Thevetia peruviana stating: "The absorption of the equivalent of two Thevetia peruviana leaves may be sufficient to kill a 12.5 kg (28lb) child (Ellenhorn and Barceloux, 1988)". Be wary if you use this species as an ornamental in your garden or indoor plant!

Posted by: Daniel Mosquin      Read more     Source


January 7, 2011, 6:56 AM CT

Statistical Analysis for Crop Performance

Statistical Analysis for Crop Performance
American Society of Agronomy
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

Biofuel grasslands better for birds
A Henslow's sparrow, threatened in Michigan, in its prairie habitat. Photo by Matt Sileo

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

Making plant breeding easier
The loss of function of RF1A1/ALDH2B2, a fertility restorer (RF) protein causes maize susceptibility to Helminthosporium maydis, the causal agent that was responsible for the maize southern corn leaf blight epidemic in 1972. The disease symptoms on a maize leaf are pictured.

Credit: Photo by Simeon O. Kotchoni

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


December 30, 2010, 6:44 AM CT

Hybrid string blossom thinner tested in peach orchards

Hybrid string blossom thinner tested in peach orchards
The new thinner prototype thins blossoms in perpendicular V or open center trained peach trees.

Credit: Photo by M. Wherley

Peach producers have traditionally relied heavily on hand thinning, a necessary but costly and labor-intensive field practice. Impacted by increasing labor costs and a limited workforce, peach and other stone fruit growers are turning to mechanical methods such as string thinners to minimize the need for hand thinning. A new ''hybrid'' string thinner prototype showed promising results when it was reviewed in four U.S. growing regions; the trials resulted in significant labor savings and increased peach size.

As per Pennsylvania State University's T. Auxt Baugher, corresponding author for the research report published in HortTechnology, the goal of the study was to determine if a new string thinner prototype designed to thin vase or angled tree canopies could be adapted for varying orchard systems. Trials with the hybrid mechanical blossom string thinner were performed in California, South Carolina, Washington, and Pennsylvania commercial orchards. The prototype used in the experiments was a hybrid of a vertical rotating string thinner designed to remove apple blossoms in organic orchards and a horizontal prototype reviewed in prior peach thinning trials. The scientists reviewed blossom removal rate, fruit set, labor mandatory for follow-up hand thinning, fruit size distribution at harvest, yield, and economic impact. Additional information was collected using case study interviews of growers and orchard managers.........

Posted by: Erica      Read more         Source

  Blogroll
  • Health Quotes
  • What is this?
  • Vacation blog
  • Zitlife
  • Blueday
  • Blogspan
  • Zit Meds



  • Older Blog Entries   1   2   3   4   5   6   7   8   9   10   11   12   13   14   15   16   17   18   19   20   21   22   23   24   25   26   27   28   29   30   31   32   33   34   35   36   37   38   39   40   41   42   43   44   45   46   47   48   49   50   51   52  
    Avocado fruit, recipes    Zit life    Zit Meds