Home Animal science blog Plant science blog Biology blog

Biology Blog

Subscribe To Biology Blog RSS Feed  RSS content feed What is RSS feed?

November 18, 2009, 11:43 PM CT

With a beam of light

With a beam of light
This tiny worm became temporarily paralyzed when scientists fed it a light-sensitive material, or "photoswitch," and then exposed it to ultraviolet light. Credit: American Chemical Societypress esc to close
In an advance with overtones of Star Trek phasers and other sci-fi ray guns, scientists in Canada are reporting development of an internal on-off "switch" that paralyzes animals when exposed to a beam of ultraviolet light. The animals stay paralyzed even when the light is turned off. When exposed to ordinary light, the animals become unparalyzed and wake up. Their study appears in the Journal of the American Chemical Society (JACS). It reports the first demonstration of such a light-activated switch in animals.

Neil Branda and colleagues point out that such "photoswitches" -- light-sensitive materials that undergo photoreactions -- have been available for years. Scientists use them in research. Doctors use light-sensitive materials and photoreactions in medicine in photodynamic therapy to treat certain forms of cancer. Those light-sensitive materials, however, do not have the reversibility that exists in photoswitching.

The JACS report describes development and successful testing of a photoswitch composed of the light-sensitive material, dithienylethene. The scientists grew transparent, pinhead-sized worms (C. elegans) and fed them a dithienylethene. When exposed to ultraviolet light, the worms turned blue and became paralyzed. When exposed to visible light, the dithienylethene became colorless again and the worms' paralysis ended. Many of the worms lived through the paralyze-unparalyze cycle. Scientists were not sure how the switch causes paralysis. The study demonstrates that photoswitches may have great potential in turning photodynamic therapy on and off, and for other applications in medicine and research, they indicate.........

Posted by: Kelly      Read more         Source


November 18, 2009, 11:16 PM CT

How crops survive drought

How crops survive drought
This image shows abscisic acid (purple molecule at center) inside its receptor. Carbon atoms are purple, oxygen atoms are red and hydrogen atoms are not shown. The phosphatase, which also makes contact with the receptor, is shown in green.

Credit: Cutler lab, UC Riverside.

Breakthrough research done earlier this year by a plant cell biologist at the University of California, Riverside has greatly accelerated scientists' knowledge on how plants and crops can survive difficult environmental conditions such as drought.

Working on abscisic acid (ABA), a stress hormone produced naturally by plants, Sean Cutler's laboratory showed in April 2009 how ABA helps plants survive by inhibiting their growth in times when water is unavailable research that has important agricultural implications.

The Cutler lab, with contributions from a team of international leaders in the field, showed that in drought conditions certain receptor proteins in plants perceive ABA, causing them to inhibit an enzyme called a phosphatase. The receptor protein is at the top of a signaling pathway in plants, functioning like a boss relaying orders to the team below that then executes particular decisions in the cell.

Now recent published studies show how those orders are relayed at the molecular level. ABA first binds to the receptor proteins. Like a series of standing dominoes that begins to knock over, this then alters signaling enzymes that, in turn, activate other proteins resulting, eventually, in the halting of plant growth and activation of other protective mechanisms.........

Posted by: Erica      Read more         Source


November 18, 2009, 11:06 PM CT

Evolution of Highly Toxic Box Jellyfish

Evolution of Highly Toxic Box Jellyfish
Craybdea branchi, a box jellyfish native to the South African coast. (Image courtesy of Brent Viljoen)
With thousands of stinging cells that can emit deadly venom from tentacles that can reach ten feet in length, the 50 or so species of box jellyfish have long been of interest to researchers and to the public. Yet little has been known about the evolution of this early branch in the animal tree of life.

In a paper published November 18 in the Proceedings of the Royal Society, NOAA scientists Allen Collins, Bastian Bentlage and Cheryl Lewis Ames of the Northeast Fisheries Science Center's National Systematics Laboratory and his colleagues from the University of Kansas, Pacific Biosciences Research Center in Hawaii and the University of Queensland in Australia have unraveled the evolutionary relationships among the various species of box jellyfish, thereby providing insight into the evolution of their toxicity.

"By determining the relationships among the different box jellyfish, some of which are capable of killing a healthy human, this study can help in the future development of antivenoms and therapys for their stings," said Collins, a specialist in Cnidaria (pronounced nidaria), the phylum of animals that includes box jellyfish. "Scientists will now be able to make more informed choices about organisms for future venom studies, and make predictions on which species are likely to be of public health concern in addition to the known culprits".........

Posted by: Kelly      Read more         Source


November 17, 2009, 8:46 AM CT

Right-Handed Chimpanzees: Origin of Human Language

Right-Handed Chimpanzees: Origin of Human Language
female in order to greet her. (Credit: William D. Hopkins)
Most of the linguistic functions in humans are controlled by the left cerebral hemisphere. A study of captive chimpanzees at the Yerkes National Primate Research Center (Atlanta, Georgia), published in the January 2010 issue of Elsevier's Cortex, suggests that this "hemispheric lateralization" for language may have its evolutionary roots in the gestural communication of our common ancestors. A great majority of the chimpanzees in the study showed a significant bias towards right-handed gestures when communicating, which may reflect a similar dominance of the left hemisphere for communication in chimpanzees as that seen for language functions in humans.

A team of researchers, supervised by Prof. William D. Hopkins of Agnes Scott College (Decatur, Georgia), studied hand-use in 70 captive chimpanzees over a period of 10 months, recording a variety of communicative gestures specific to chimpanzees. These included 'arm threat', 'extend arm' or 'hand-slap' gestures produced in different social contexts, such as attention-getting interactions, shared excitation, threat, aggression, greeting, reconciliation or invitations for grooming or for play. The gestures were directed at the human observers, as well as toward other chimpanzees.

"The degree of predominance of the right hand for gestures is one of the most pronounced we have ever found in chimpanzees compared to other non-communicative manual actions. We already found such manual biases in this species for pointing gestures exclusively directed to humans. These additional data clearly showed that right-handedness for gestures is not specifically associated to interactions with humans, but generalizes to intraspecific communication," notes Prof. Hopkins.........

Posted by: Kelly      Read more         Source


November 17, 2009, 8:37 AM CT

New atlas by tracking Penguins and sea lions

New atlas by tracking Penguins and sea lions
Southern elephant seals were fitted with GPS collars to help provide data for the new atlas. (Credit: Valeria Falabella/Wildlife Conservation Society)
Recording hundreds of thousands of individual uplinks from satellite transmitters fitted on penguins, albatrosses, sea lions, and other marine animals, the Wildlife Conservation Society (WCS) and BirdLife International have released the first-ever atlas of the Patagonian Sea a globally important but poorly understood South American marine ecosystem.

The atlas contains the most accurate maps ever assembled for this ecosystem revealing key migratory corridors that span from coastlines to deep-sea feeding areas off the continental shelf hundreds of miles away.

Data for the atlas was gathered by a team of 25 researchers working over a 10-year period a number of of them supported by the National Research Council of Argentina (CONICET). The team tracked 16 species of marine animals, which produced some 280,000 individual uplinks of data over the Patagonian Sea, a huge area ranging from southern Brazil to southern Chile.

Called Atlas of the Patagonian Sea: Species and Spaces, the 300-page book was edited by Valeria Falabella and Claudio Campagna of the Wildlife Conservation Society, and John Croxall of Birdlife International.

The atlas, which is in English and Spanish, will be used to help inform potential policy decisions in the region such as managing fisheries and charting transportation routes of oil tankers. This vast region, which spans 3 million square kilometers (1.1 million square miles), is becoming increasingly threatened by burgeoning development and overfishing.........

Posted by: Kelly      Read more         Source


November 17, 2009, 8:05 AM CT

Plants prefer their kin

Plants prefer their kin
Plants don't mind sharing space with their kin but when they're potted with strangers of the same species they start invigorating their leaves, a study by McMaster University reveals.

The research, which appears in the current issue of the American Journal of Botany, suggests non-kin plants will not only compete underground for soil nutrients, but will attempt to muscle out the competition above ground in the ongoing struggle for light.

It follows prior research from McMaster University which observed that plants can recognize their kin through root systems and will compete more strongly for soil nutrients and water with non-sibling plants.

"This is the first study that shows plants are responding to kin at the above ground level," explains Guillermo Murphy, main author of the study and a graduate student in the Department of Biology at McMaster University. "When they recognize their kin, they grow differently in shape, taller, with more branches and fewer resources into leaves, therefore allowing their siblings to access precious sunlight."

When scientists planted seedlings of a North American species of shade-loving Impatiens in the same pot, they reacted mildly with other offspring from the same mother plant. But when planted among non-kin of the same species, the plants shift extra resources into growing leaves.........

Posted by: Erica      Read more         Source


November 13, 2009, 8:01 AM CT

Sponges recycle carbon to give life to coral reefs

Sponges recycle carbon to give life to coral reefs
Coral reefs support some of the most diverse ecosystems on the planet, yet they thrive in a marine desert. So how do reefs sustain their thriving populations?

Marine biologist Fleur Van Duyl from the Royal Netherlands Institute for Sea Research is fascinated by the energy budgets that support coral reefs in this impoverished environment. As per van Duyl's former student, Jasper De Goeij, Halisarca caerulea sponges grow in the deep dark cavities beneath reefs, and 90% of their diet is composed of dissolved organic carbon, which is inedible for most other reef residents. But when De Goeij measured the amount of carbon that the brightly coloured sponges consumed he observed that they consume half of their own weight each day, yet they never grew. What were the sponges doing with the carbon? Were the sponges really consuming that much carbon, or was there a problem with De Goeij's measurements? He had to find out where the carbon was going to back up his measurements and publishes his discovery that sponges have one of the fastest cell division rates ever measured, and instead of growing they discard the cells. Essentially, the sponges recycle carbon that would otherwise be lost to the reef. De Goeij publishes his discovery on November 13 2009 in The Journal of Experimental Biology at http://jeb.biologists.org.........

Posted by: Kelly      Read more         Source


November 12, 2009, 6:13 PM CT

First aquarium to breed dwarf cuttlefish

First aquarium to breed dwarf cuttlefish
They may look like a cluster of purple grapes, but these inky balls are actually eggs from a dwarf cuttlefish, Sepia bandensis. As the eggs continue to develop, they become translucent, at which point the babies can be seen swimming inside their egg casings. To date, more than 350 dwarf cuttlefish have hatched at the California Academy of Sciences, most of which have been sent to other aquariums and research institutions. The academy is the first institution in the country to successfully breed these animals.

Credit: Richard Ross, California Academy of Sciences

Anchored to an algae-covered rock in a 120-gallon tank at the California Academy of Sciences' Steinhart Aquarium, a cluster of inky-colored cuttlefish eggs is beginning to swellevidence of success for the Academy's new captive breeding program for dwarf cuttlefish, Sepia bandensis. The program, pioneered by Academy biologist Richard Ross, is the first of its kind in a U.S. aquarium, and offers the Academy and other institutions the opportunity to study and display a species that is both captivating andat 2-4 inches in lengthless resource-intensive to keep than its larger relatives. "By establishing a stable breeding population," Ross explains, "our hope is to make it easier for aquariums to showcase cuttlefish and their remarkable characteristics without impacting wild populations".

While called "cuttlefish," these animals are actually not fish at allthey are members of the class Cephalopoda, which also includes octopus, squid, and the chambered nautilus. Perhaps best known for their highly developed brains, nervous systems, and eyes, cephalopods are a fascinating group of animals to both scientists and aquarium visitors. For scientists, cephalopods' advanced capabilities pose a host of unanswered questions about the nature of intelligence in invertebrates and vertebrates. For everyday observers, the dwarf cuttlefish is a captivating ambassador to its Cephalopoda class, and its native Indo-Pacific region. Able to rapidly change its skin color, Sepia bandensis frequently flashes moving patterns across its skin, and can quickly blend into its surroundingsphenomena that can be seen regularly in the Steinhart Aquarium display. Beneath that ever-changing skin, the dwarf cuttlefish's physiology is equally remarkable, with three hearts, and an esophagus that passes through its brain.........

Posted by: Kelly      Read more         Source


November 11, 2009, 10:06 PM CT

The inner realm of living cells

The inner realm of living cells
A tiny glass fiber is used to vaporize contents of cells to study the cell contents.

Credit: American Chemical Society

Researchers in Washington, DC, are reporting development and successful tests of a new way for exploring the insides of living cells, the microscopic building blocks of all known plants and animals. They explode the cell while it is still living inside a plant or animal, vaporize its contents, and sniff. The study appears in online in ACS' journal Analytical Chemistry

Akos Vertes and Bindesh Shrestha note that knowing the contents of cells is the key to understanding how healthy cells differ from those in disease. Until now, however, the only way to "look" inside an individual cell was to remove it from its natural environment in an animal or plant, or change its environment. But doing so changed the cell. Researchers never knew whether one cell differed from another because of the disease, or because they had removed it to a new environment.

The new report describes development of a new technique that uses laser pulses focused through a tiny glass fiber to explode a cell and turn its contents into vapor. Researchers then use a laboratory instrument to analyze the vapor and get a profile of the chemicals inside. It can reveal differences between diseased and healthy cells, even between adjacent cells in the same tissue. The researchers used this new technique to analyze the contents of living plant and animal cells and show that it quickly and accurately identified important chemical details that would have been overlooked using conventional techniques.........

Posted by: Janet      Read more         Source


November 11, 2009, 8:07 AM CT

World's first voluntary gorilla blood pressure reading

World's first voluntary gorilla blood pressure reading
Ozzie, a 48-year-old male western lowland gorilla at Zoo Atlanta, was the first gorilla to voluntarily have his blood pressure measured with the Gorilla Tough Cuff designed by Georgia Tech students.

Credit: Zoo Atlanta
Zoo Atlanta recently became the first zoological institution in the world to obtain voluntary blood pressure readings from a gorilla. This groundbreaking stride was made possible by the Gorilla Tough Cuff, a blood pressure reading system devised through partnership with the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University.

Created as a senior design project by biomedical engineering undergraduates David Sotto, Nisha Bhatia, Stephanie Drewicz and Scott Seaman, the prototype has now been successfully tested on one of Zoo Atlanta's 22 western lowland gorillas. The students also had guidance from Hanjoong Jo, the Ada Lee and Pete Correll Professor in Biomedical Engineering and the Division of Cardiology; and Professor Franklin Bost, the Coulter Department director of design instruction.

"Zoo Atlanta is home to the nation's largest collection of gorillas, so there is an ongoing responsibility to contribute to the zoological community's understanding of their care," said Dennis Kelly, President and CEO. "We are proud to have spearheaded an effort that will ultimately benefit gorillas living in captive settings around the world."

The Gorilla Tough Cuff operates in the same manner as the mechanism familiar to humans, with the patient slipping an arm into a cuff. As the cuff inflates, the blood pressure reading is measured and displayed on a monitor. The student design team's biggest set of challenges, however, was constructing a durable, comfortable cuff large enough to fit an adult male gorilla weighing upwards of 300 pounds.........

Posted by: Kelly      Read more         Source


November 11, 2009, 8:00 AM CT

Eyeless, mouthless worms lurk in the dark

Eyeless, mouthless worms lurk in the dark
This photograph shows a female of an as yet un-named boneworm in the genus Osedax, which has been carefully removed from the whale bone in which it was growing. This worm has green, feathery palps, which extract oxygen from seawater. At its lower end are an ovisac and bulbous "roots," which would normally be embedded in the whale bone.
Image: © 2009 Greg Rouse
It sounds like a classic horror story-eyeless, mouthless worms lurk in the dark, settling onto dead animals and sending out green "roots" to devour their bones. In fact, such worms do exist in the deep sea. They were first discovered in 2002 by scientists at the Monterey Bay Aquarium Research Institute (MBARI), who were using a robot submarine to explore Monterey Canyon. But that wasn't the end of the story. After "planting" several dead whales on the seafloor, a team of biologists recently announced that as a number of as 15 different species of boneworms may live in Monterey Bay alone.

After years of study, the scientists have begun to piece together the bizarre story of the boneworms, all of which are in the genus Osedax. The worms start out as microscopic larvae, drifting through the darkness of the deep sea. At some point they encounter a large dead animal on the seafloor. It appears to be a whale, an elephant seal, or even the carcass of a cow that washed out to sea during a storm. Following chemical cues, the tiny larvae settle down onto the bones of the dead animal.

Once settled, the boneworms grow quickly, like weeds after a rain. One end of each worm develops feathery palps, which extract oxygen from seawater. The other end of the worm develops root-like appendages that grow down into the bone. Bacteria within these roots are believed to digest proteins and perhaps lipids within the bones, providing nutrition for the worms.........

Posted by: Kelly      Read more         Source


November 10, 2009, 9:00 AM CT

Fig-wasps travel hundreds of miles

Fig-wasps travel hundreds of miles
Illustrations and photographs credit and © Simon van Noort (Iziko Museums of Cape Town)
They may only be 1.5mm in size, but the tiny wasps that pollinate fig trees can travel over 160km in less than 48 hours, as per research from researchers at the University of Leeds. The fig wasps are transporting pollen ten times further than previously recorded for any insect.

The fig wasps travel these distances in search of trees to lay their eggs, which offers hope that trees pollinated by similar creatures have a good chance of surviving if they become isolated through deforestation.

"Fig trees provide very important food for vertebrates," explains Dr Stephen Compton of the University's Faculty of Biological Sciences. "More birds and animals feed on fig trees than on any other plant in the rainforest. Our research shows that trees pollinated by this type of insect should be very resistant to forest fragmentation".

"Fig wasps are weak flyers," added Dr Compton. "They fly up in an air column and are then carried by wind until they sense host figs at which point they drop close to the ground and hunt out the scent of the tree which is specific to them.

"As adult wasps live for just 48 hours, they must have travelled these distances incredibly fast. It took our field researchers and volunteers nearly two weeks to walk 250km and map the fig trees used in the research".........

Posted by: Kelly      Read more         Source


November 5, 2009, 8:42 AM CT

Making better broccoli

Making better broccoli
Carotenoidsfat-soluble plant compounds found in some vegetablesare essential to the human diet and reportedly offer important health benefits to consumers. Plant carotenoids are the most important source of vitamin A in the human diet; the carotenoids lutein and zeaxanthin, found in corn and leafy greens vegetable such as kale, broccoli, and spinach, are widely considered to be valuable antioxidants capable of protecting humans from chronic diseases including age-related macular degeneration, cancer, and cardiovascular disease.

Vegetables in the cabbage family (such as kale, cauliflower, and broccoli) have long been known as particularly good sources of dietary carotenoids. Recently, broccoli has emerged as the stand-out member of the species, providing more carotenoids to American consumers than any of its cabbage-family relatives. Yet, little has been understood about the carotenoid make-up of this popular green vegetableuntil now.

Mark W. Farnham of the U.S. Department of Agriculture, Agricultural Research Service, Charleston, South Carolina, and Dean A. Kopsell from the Plant Sciences Department, University of Tennessee, Knoxville, designed a research study aimed at finding out more about the carotenoid content of field-grown broccoli and determining the effects of genetics and the environment on carotenoid levels. The duo's research confirmed that broccoli heads contain abundant levels of lutein, an antioxidant usually thought to provide nutritional support to eyes and skin. Other carotenoids like beta-carotene, violaxanthin, neoxanthin, and antheraxanthin were also found in broccoli heads, but lutein was clearly the most significant, accounting for about half of all carotenoids measured.........

Posted by: Erica      Read more         Source


November 5, 2009, 8:39 AM CT

Indoor plants to fight air pollution

Indoor plants to fight air pollution
Hemigraphis alternata, or purple waffle plant, one of the highest rated ornamentals for removing indoor air pollutants.

Credit: Photo courtesy of Dr. Stanley Kays

Air quality in homes, offices, and other indoor spaces is becoming a major health concern, especially in developed countries where people often spend more than 90% of their time indoors. Surprisingly, indoor air has been reported to be as much as 12 times more polluted than outdoor air in some areas. Indoor air pollutants emanate from paints, varnishes, adhesives, furnishings, clothing, solvents, building materials, and even tap water. A long list of volatile organic compounds, or VOCs [including benzene, xylene, hexane, heptane, octane, decane, trichloroethylene (TCE), and methylene chloride], have been shown to cause illnesses in people who are exposed to the compounds in indoor spaces. Acute illnesses like asthma and nausea and chronic diseases including cancer, neurologic, reproductive, developmental, and respiratory disorders are all associated with exposure to VOCs. Harmful indoor pollutants represent a serious health problem that is responsible for more than 1.6 million deaths each year, as per a 2002 World Health Organization report.

Stanley J. Kays, Department of Horticulture, University of Georgia, was the lead researcher of a study published in HortScience that tested ornamental indoor plants for their ability to remove harmful VOCs from indoor air. As per Kays, some indoor plants have the ability to effectively remove harmful VOCs from the air, and not only have the ability to improve our physical health, but also have been shown to enhance our psychological health. Adding these plants to indoor spaces can reduce stress, increase task performance, and reduce symptoms of ill health.........

Posted by: Erica      Read more         Source


November 5, 2009, 8:37 AM CT

Seeking flower variety

Seeking flower variety
Florists and other retailers who sell flowers and plants can now add another tool to their marketing kit. A recent study of "consumption values" may help them understand what influences consumers' choices in regard to floral purchases, and how to better design marketing efforts and purchase stock that can increase customers and sales.

Li-Chun Huang from National Taiwan University and Tzu-Fang Yeh from Da-Yeh University headed a research project that reviewed the differences in floral consumption values across consumer groups (the full study appears in a recent issue of HortTechnology).

A consumer survey was conducted in cities and rural areas in Taiwan in 2006 where 677 participants were surveyed. As per responses to a survey question that asked whether they purchased flowers, participants were divided into two categories: ''users'' and ''nonusers'' of flowers.

The majority of survey participants indicated that the following values (in descending order) influenced their floral purchases: showing care to others, emotion conditioning, and "sensory hedonics", a phenomenon in which consumers perceive the value of flowers based on touching, smelling, or tasting them. Interestingly, those participants identified as "heavy users" of flowers revealed different priorities, rating "emotion conditioning" as more important than "showing care to others". The scientists note that this implies that "heavy users" make more frequent floral purchase flowers partly because they are more emotionally stimulated by flowers. Heavy users also rated "curiosity fulfillment" higher, leading to them to look for more novelty and variety when purchasing flowers.........

Posted by: Erica      Read more         Source


November 4, 2009, 8:19 AM CT

Sustainably grown garlic

Sustainably grown garlic
Colorful new varieties of garlic are becoming popular with consumers.

Credit: Photo courtesy of Gayle M. Volk

Consumer interest in new and diverse types of garlic is on the rise. Fueled by factors including the growth of the "local foods" movement, interest in world cuisines, and widespread reports touting its numerous health benefits, demand for high-quality, locally grown garlic is increasing throughout the U.S.

While most grocery stores in carry the familiar white, "softneck" garlic (which is most often imported), varieties of "hardneck" garlic in colorful hues of purple, magenta, pink, and white are becoming more available at local vegetable stands and through direct-marketing programs. The results of a recent study of 10 garlic cultivars can help farmers identify niche regional markets and offer new, in-demand garlic varieties to consumers.

Hundreds of garlic (Allium sativum L.) cultivars are available from seed companies, retailers, and germplasm collections. Increasingly, growers purchase bulbs from nonlocal sources and are often disappointed by unpredictable yields. Garlic bulbs resulting from seed stock purchased in other regions may not display the characteristicssuch as bulb size, shape, and colorfeatured in the catalogs.

Gayle M. Volk of the National Center for Genetic Resources Preservation, U.S. Department of Agriculture's Agricultural Research Service in Fort Collins, and David Stern of the Garlic Seed Foundation authored a study designed to determine which garlic traits are stable and which traits vary depending on where the garlic is grown. As per the study published in a recent issue of HortScience and funded primarily by the Northeast Sustainable Agricultural Research and Education program, previous research has shown that traits such as clove number, clove skin coloration, and topset number are representative of cultivar type across growth locations, whereas "phenotypic" traits such as bulb wrapper color, bulb size, and bulb elemental composition are specific to sites.........

Posted by: Erica      Read more         Source


November 4, 2009, 8:16 AM CT

Pecan trees benefit from thinning

Pecan trees benefit from thinning
Mechanical thinning of pecan trees is shown using a tree shaker with a hydraulic shaker head.

Credit: Photo courtesy of Dr. M. Lenny Wells

Pecan trees, like many fruit trees, have a tendency to bear fruit in cycles, producing a large crop in one or two years, followed by one or two years with little or no crop. This cycle, called "alternate bearing", is the most profit-limiting biological problem facing pecan producers; the inconsistent production pattern creates supply and marketing challenges that can have severe negative effects on the pecan industry.

Producers have experienced success using mechanical fruit thinning as a way to minimize the effects of alternate bearing on several pecan cultivars. While the protocol for mechanical crop thinning has been established for some pecan cultivars grown in Oklahoma and Kansas, little research has been conducted regarding the economic value and potential profitability of fruit thinning of cultivars found in the southeastern United States. To address this issue, researchers at the University of Georgia's Department of Horticulture studied the effects of mechanical fruit thinning on pecan yield, nut quality, and profitability using 'Sumner' and 'Cape Fear' pecan trees, two important cultivars prevalent in areas of the southeastern U.S. The research study was published in a recent issue of HortTechnology

Ten 20-year-old trees of both 'Sumner' and 'Cape Fear' were used for the study. Trees grown in Tifton loamy sand soil in a commercial pecan orchard in Irwin County, Georgia, were used for the study. The trees were spaced 40 x 40 feet and were drip-irrigated. Treatments were replicated five times in a randomized complete-block design. Five trees of each cultivar were mechanically thinned using a tree shaker with a hydraulic shaker heada process called trunk shakingto remove 30% to 40% of the fruit on each tree, and five trees were not thinned.........

Posted by: Erica      Read more         Source


November 4, 2009, 8:15 AM CT

For African violets

For African violets
People like to feel the soft, often hairy leaves of African violets, but touching the leaves can cause damage to the plants.

Credit: Photo by Donna Dollins
African violets have a mixed reputation. Their delicate, colorful flowers and furry, soft leaves make them a favorite among home gardeners and growers. But the striking plants are often regarded as temperamental: a precise recipe of light, moisture, warm temperatures, high humidity, and fertilizer is mandatory to encourage african violets to grow and flower.

A recently published study by researchers Julia C. Brotton and Janet C. Cole from the Department of Horticulture and Landscape Architecture at Oklahoma State University (in a recent issue of HortTechnology) could provide african violet enthusiasts with important care information about the finicky flower.

Because of their brightly colored flowers and hairy leaves, people are attracted to african violets and often want to touch the leaves and flowers. But how does all this attention affect the plants? The research team set out to determine the effect of "brushing" african violet leaves on plant growth and quality. Cole explained, "Because (african violet) growers work in conditions that can contribute to the development of dry, irritated skin, a number of growers use body lotions to help soothe and moisturize their dry skin. A number of consumers also use these products. Our study researched whether touching or "brushing" african violet leaves causes damage, especially when body lotion or other skin care products have been applied to hands before touching the plants".........

Posted by: Erica      Read more         Source


November 4, 2009, 8:10 AM CT

White sharks in the north Pacific

White sharks in the north Pacific
A white shark tagged with both acoustic (front) and pop-up satellite (rear) tags. The acoustic tag is detected when the shark swims within 250 m of a listening station, while the pop-up satellite tag records information about location, temperature and depth -- and relays it to the laboratory when the tag releases itself from the shark.

Credit: Courtesy: TOPP

The white shark appears to be the ultimate loner of the ocean, cruising thousands of miles in a solitary trek, but a team of scientists has discovered that the sharks have maintained such a consistent pattern of migration that over tens of thousands of years the white sharks in the northeastern Pacific Ocean have separated themselves into a population genetically distinct from sharks elsewhere in the world.

"White sharks are a large, highly mobile species," said Salvador Jorgensen, a postdoctoral scholar at Stanford's Hopkins Marine Station. "They can go just about anywhere they want in the ocean, so it's really surprising that their migratory behaviors lead to the formation of isolated populations".

Researchers with the Tagging of Pacific Predators (TOPP) program combined satellite tagging, passive acoustic monitoring and genetic tags to study white sharks (Carcharodon carcharias) popularly known as great white sharks in the North Pacific. The team consisted of scientists from Stanford University, University of California-Davis, Point Reyes Bird Observatory and the Pelagic Shark Research Foundation, and the details of their study are to be published online Nov. 3 by the Proceedings of the Royal Society B

The fact that the northeastern Pacific white sharks undergo such a consistent, large-scale migration, and that they are all closely related and distinct from other known white shark populations, suggests that it is possible to conduct long-term population evaluation and monitoring of these animals.........

Posted by: Kelly      Read more         Source


November 4, 2009, 7:59 AM CT

Cultured pearls from the queen conch

Cultured pearls from the queen conch
The queen conch is the largest molluscan gastropod of the six conch species found in the shallow seagrass beds of Florida, the Bahamas, Bermuda, the Caribbean Islands and the northern coasts of Central and South America.

Credit: FAU's Harbor Branch Oceanographic Institute

For more than 25 years, all attempts at culturing pearls from the queen conch (Strombus gigas) have been unsuccessfuluntil now. For the first time, novel and proprietary seeding techniques to produce beaded (nucleated) and non-beaded cultured pearls from the queen conch have been developed by researchers from Florida Atlantic University's Harbor Branch Oceanographic Institute (HBOI). With less than two years of research and experimentation, Drs. Hctor Acosta-Salmn and Megan Davis, co-inventors, have produced more than 200 cultured pearls using the techniques they developed. Previous to this breakthrough, no high-quality queen conch pearl had been cultured. This discovery opens up a unique opportunity to introduce a new gem to the industry. This significant accomplishment is comparable to that of the Japanese in the 1920s when they commercially applied the original pearl culture techniques developed for pearl oysters.

HBOI has been working with the Gemological Institute of America (GIA) to conduct extensive laboratory testing of the queen conch cultured pearls. In its independent analysis, GIA used techniques that included conventional gemological examination, chemical composition, spectroscopy, spectrometry and microscopy. HBOI and GIA plan to jointly publish the results of these trials in an upcoming issue of GIA's scientific journal, Gems & Gemology........

Posted by: Kelly      Read more         Source

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



  • 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   53   54   55   56   57   58   59   60   61   62   63   64   65   66   67   68   69   70   71   72   73   74   75   76   77   78   79   80   81   82   83   84   85   86   87   88   89   90   91   92   93   94   95   96   97   98   99   100   101   102   103   104   105   106   107   108   109   110   111   112   113   114   115   116   117   118   119   120   121   122   123   124   125   126   127   128   129   130   131   132   133   134   135   136   137   138   139   140   141   142   143   144   145   146   147   148   149   150   151  
    World Science    cme courses