All Stages From Life To Death
Taken on the grounds of the Gilcrease Museum in Tulsa, Oklahoma.
I thought it was very cool how this one leaf displays all of the stages from life to death.
Via Flicker.........
Posted by: Jessica Permalink Source
                  |
 Net World Directory Your personal directory for the internet | ||
| Net World Directory: Archives of botany blog |
 | ||
Archives Of Botany Blog From NetworlddirectorySubscribe To Botany Blog RSS Feed 
Taken on the grounds of the Gilcrease Museum in Tulsa, Oklahoma. I thought it was very cool how this one leaf displays all of the stages from life to death. Via Flicker......... Posted by: Jessica Permalink Source Lachenalia Mutabilis
The epithet "mutabilis" means "changeable", in this case referring to the inflorescence - the immature stalk and flowers start blue and turn yellowish-green or pinkish as they age. For photographs of the entire inflorescence with the range of colours, see this page from the International Bulb Society and the Lachenalia page from the Pacific Bulb Society's Wiki. Photography resource link: Nature's Best Photography Magazine's International Awards - scroll down in the middle frame of the page for links to the 2004-2006 award winners. Also, there's a Picture of the Week feature on the site that might interest you......... Posted by: Jessica Permalink Source Wild Bees Make Honeybees Better Pollinators
"As honeybees become more scarce, it becomes more important to have better pollinators," said Sarah Greenleaf, a postdoctoral researcher at UC Davis and first author on the study. As a graduate student at Princeton University, Greenleaf carried out a two-year study of honeybees used to pollinate sunflower crops on farms in Yolo County, Calif., near UC Davis. Compared to honeybees, wild bees did not contribute much directly to crop pollination. But on farms where wild bees were abundant, honeybees were much more effective in pollinating flowers and generating seeds, Greenleaf found. There appear to be two reasons for that. Male wild bees, probably looking for mates, will latch onto worker honeybees, which are sterile females, causing them to move from one flower to another. Secondly, female wild bees appear to "dive bomb" honeybees, forcing them to move. Frequent movement between flowers spreads pollen around more effectively. Greenleaf and her co-author Claire Kremen, now a professor at UC Berkeley, calculated that wild bees contributed about $10 million of value to the $26-million sunflower industry alone......... Posted by: Ashley Permalink Source Watching Seeds In 3D
Scientists have identified individual cells within the seed and rendered them to show their three-dimensional organisation. They have also distinguished an intercellular air network, which should represent an important circulation system for air and perhaps water during germination. However, researchers can't yet assure that this is the path the oxygen follows to "feed" the seed: "Solving this question needs a nano-method to determine the exact composition of air in the network during seed formation, but unfortunately this method is not available yet", explains Silva Lerbs-Mache, the corresponding author of the paper. The researchers used hard X-ray-based quantitative phase tomography at ESRF beamline ID19 to obtain three-dimensional images of an arabidopsis seed. This seed is a model plant for biologists and the first one for which the genome was sequenced. "This approach is to our knowledge the only imaging technique with the penetration capacity and imaged field size suited for an investigation at sub-micrometre resolution of an optically opaque object the size of a seed" explains Peter Cloetens, first author of the paper and scientist at the ESRF. It is applied for the first time to an autonomous living system, observed without object destruction, without staining, in air, and at room temperature......... Posted by: Jessica Permalink Source MIT Team Describes Unique Cloud Forest
In an area that is characterized mostly by desert, the trees have preserved an ecological niche because they exploit a wispy-thin source of water that only occurs seasonally, said Elfatih A.B. Eltahir, professor of civil and environmental engineering, and former MIT graduate student Anke Hildebrandt. After studying the Oman site, they also expressed concern that the unusual forest could be driven into extinction if hungry camels continue eating too much of the foliage. As the greenery disappears it's possible the trees will lose the ability to pull water from the mist and recharge underground reservoirs. A report on their research was published in a recent issue of Geophysical Research Letters. They are also advising the Omani government on handling the problem. The forest is particularly unique, said Eltahir and Hildebrandt, because it "is a water-limited seasonal cloud forest" that is kept alive by water droplets gathered from passing clouds -- ground fog. The water dribbles into the ground and sustains the trees later when the weather is dry. The MIT work suggests the trees actually get more of their water through contact with clouds than via rainfall......... Posted by: Tyler Permalink Source Mechanisms of Sudden Oak Death
California Bay Laurel leaves infected with Phytophthora ramorum
"This project best exemplifies how the capabilities that were established at the DOE JGI for sequencing the human genome are now proving to be essential for addressing important environmental challenges," said Eddy Rubin, DOE JGI Director. "We are now capable of rapidly responding to the urgent needs of the nation's largest industry, agriculture, where genome sequence information can be brought to bear on characterizing such economically important microorganisms as those that cause sudden oak death and soybean root rot. For these pathogens, the genome sequence is the wiring diagram of the cellular processes that can be targeted for novel detection systems and for safe and effective means of control"......... Posted by: Jessica Permalink Source Do green markets actually lead to improvements in environmental quality?
Using a model of impure public goods, Matthew J. Kotchen (University of California, Santa Barbara) analyzes goods that have both private and public components, each of which is available individually. For example, shade-grown coffee is grown not on deforested plantations, but under the canopy of tropical forests. Thus, consumers are not only buying coffee, which is a traditional private good, but also biodiversity conservation. However, consumers also have the option to buy conventional coffee and donate directly to tropical conservation. "Although green markets are promoted to improve environmental quality and promote social welfare, their actual effects may be detrimental to both," writes Kotchen. "These results, along with the conditions sufficient to rule them out, provide new insight into the potential advantages and disadvantages of green markets as a decentralized mechanism of environmental policy"......... Posted by: Ashley Permalink Source Rice Domestiction Confiirmed
Photo courtesy USDA
Jason Londo, Washington University in Arts & Sciences biology doctoral candidate, and his adviser, Barbara A. Schaal, Ph.D., Washington University Spencer T. Olin Professor of Biology in Arts & Sciences, ran genetic tests of more than 300 types of rice, including both wild and domesticated, and found genetic markers that reveal the two major rice types grown today were first grown by humans in India and Myanmar and Thailand (Oryza sativa indica) and in areas in southern China (Oryza sativa japonica). Schaal said that she was surprised and "delighted" by their results. "People have moved rice around so much and the crop crosses with its wild ancestors pretty readily, so I was fully prepared to see no domestication signal whatsoever,," Schaal said. "I would have expected to see clustering of the cultivated rice, but I was delighted to see geographical clustering of the wild rice. I was thrilled that there was even genetic structure in the wild rice." In contrast to rice, other staple crops such as wheat, barley and corn appears to have been domesticated just once in history......... Posted by: Jessica Permalink Source Biological Switch from Plant Molecule
The study offers the first detailed image of chloropyhll-a - the main ingredient in the photosynthesis process - and shows how scientists can use new technology to manipulate the configuration of the spinach molecule in four different arrangements, report Ohio University physicists Saw-Wai Hla and Violeta Iancu in today's early edition of the journal Proceedings of the National Academy of Sciences. The scientists used a scanning tunneling microscope to image chlorophyll-a and then injected it with a single electron to manipulate the molecule into four positions, ranging from straight to curved, at varying speeds. (View a movie here) Though the Ohio University team and others have created two-step molecule switches using scanning tunneling microscope manipulation in the past, the new experiment yields a more complex multi-step switch on the largest organic molecule to date. The work has immediate implications for basic science research, as the configuration of molecules and proteins impacts biological functions. The study also suggests a novel route for creating nanoscale logic circuits or mechanical switches for future medical, computer technology or green energy applications, said Hla, an associate professor of physics......... Posted by: Jessica Permalink Source Weeds In The Garden
A 15-year study of flixweed, a member of the mustard family, helps explain plant population oscillations and may be useful in crop protection.
Credit: Courtesy J.L. Gonzalez-Andujar "The failure to recognize the intrinsic nature of many weed population changes may result in over-application of control inputs, with subsequent negative economic and environmental effects," says Jose Gonzalez-Andujar, who co-authored the study, forthcoming in The American Naturalist, with Cesar Fernandez-Quintanilla and Luis Navarrete. Many populations exhibit cyclic oscillations. Everybody can recall a summer where mosquitoes hindered attempts at al fresco dining. These cycles can be produced by climatic conditions or by internal feedback mechanisms. However, in contrast with studies of insect and animal populations, little attention has been directed at the study of cycles in plants. What happens with your garden weeds? The researchers demonstrate that there are some intrinsic mechanisms that explain observed plant oscillations more specifically, evidence of cycles produced by delayed density dependence in a plant population growing under field conditions. This study can have a capital importance in crop protection......... Posted by: Jessica Permalink Source |
||
| Net World Directory: Navigation |