In the U s. In virginia overabundant deer eat trees before they reach maturity while nitrogen pollution has changed soil chemistry in Canada and Panama.
and seed production collect insects survey mammals quantify carbon stocks and flows within the ecosystem take soil samples
and on welfare technologies will increasingly target at early detection of signals that predict a health problem of an animal.
and his colleagues found that a pair of the hungry herbivores could reduce phragmites cover from 94 percent to 21 percent on average by the end of the study.
Separate trials showed that horses and cows would also readily eat the invasive grass. In addition to restoring views the controlled grazing allowed native plant species to reestablish themselves in the test plots over time.
because as trees expand into these grassland areas people who are using grassland for cattle production have less grass for animals too Dodds said.
Plants use defenses against pests, but they dont always worksugars are usually known as energy storage units in plants
and the insects that feed on them. But sugars may also be part of a deadly game of tag between plant and insect according to scientists at the Max Planck Institute for Chemical Ecology.
Grasses and crops such as maize attach sugars to chemical defenses called benzoxazinoids to protect themselves from being poisoned by their own protective agents.
Then when an insect starts feeding a plant enzyme removes the sugar to deploy the active toxin.
The Max Planck scientists have discovered now why this defensive strategy fails to work against Spodoptera larvae.
When the researchers examined the frass of these pests â pests that cause enormous crop damage â they found the toxin with sugar still attached.
After the plant removes the sugar the insect reattaches it but in the opposite stereochemical configuration.
which explains the success of Spodoptera species. Plants usually defend themselves against insect feeding by producing toxins or deterrents.
However many insects have become adapted to plant defenses and can feed on plant tissues containing toxins or deterrents without the expected negative effects.
Insects overcome plant defenses by the rapid excretion sequestration or detoxification of toxic substances Not only have contributed such adaptations to the vast diversification of insects in the course of evolution they also support the success of agricultural pests specialized on certain crop plants that jeopardize crop yields every year.
With the abundance of maize grown throughout the world it is not surprising that the crop has many insect pests including larvae of the Genus spodoptera.
In North and South america the fall armyworm Spodoptera frugiperda is an important maize pest causing considerable damage.
Like all cereals and other members of the grass family maize plants defend themselves with chemistry.
The plant also produces an enzyme active in caterpillar guts which cleaves DIMBOA-glucoside to release the sugar.
The free DIMBOA formed as a result causes many insects to die or cease growing but not the fall armyworm.
A group of researchers led by Daniel Giddings Vassã£o and Jonathan Gershenzon from the Department of Biochemistry at the Max Planck Institute for Chemical Ecology in Jena Germany have discovered recently a previously unknown detoxification strategy in these pest insects.
Caterpillars of the fall armyworm and two other Spodoptera species deploy a gut enzyme that catalyzes the attachment of a sugar to the toxic free DIMBOA.
The sugar group is reattached in a mirror-image orientation (forming a (2s)- DIMBOA-glucoside) so that the plant enzyme cannot remove it a second time.
We were surprised that the difference between the insect metabolite and the original plant compound was simply the stereochemical configuration of one atom.
The crucial change however is the fact that the insect metabolite is no longer reactive to the plant enzyme
The elegance of such a mechanism comes from its simplicity yet it saves the insects from being poisoned said Felipe Wouters who performed the experiments for his doctoral thesis at the institute summarizing the results.
Like his colleague Daniel Giddings Vassã£o Felipe Wouters is from Brazil where fall armyworm caused major losses of the maize yield before Bt maize was introduced.
According to a Reuters report this summer Brazilian farmers are complaining that Bt is not protecting the plants against the fall armyworm any longer.
The increasing resistance of pest insects to Bt is another reason to look deeper into the natural insect adaptations against plant defenses.
If we can better understand how much this gut enzyme has helped the fall armyworm to become such a dangerous pest on maize we may be able to use this to our advantage by impairing this insect enzyme
and restoring the full defensive potential of maize against these pests says Daniel Giddings Vassã£o.
Plant-insect interactions involve very complex and dynamic metabolic processes. The importance of the three-dimensional structure of molecules and the stereospecificity of chemical reactions is overlooked often.
These insects can teach us humans a lot about an important chemical concept the idea that a compound
and the encoding genes that are responsible for the detoxification process in the fall armyworm. They also want to look for equivalent enzymes in related species and compare these.
If the researchers can obtain a more comprehensive picture of how benzoxazinoids are metabolized in pest insects they may be able to design better strategies to reduce pest damage.
#Captive whooping cranes released into the wildfour whooping crane chicks raised in captivity began their integration into the wild Saturday as part of the continuing effort to increase the wild population of this endangered species. The cranes hatched
The parent-reared whooping crane chicks were hatched and raised by captive adult whooping cranes. This method relies entirely on the expertise of captive parents who care for exercise
and feed the chicks. These chicks will join a flock of about 95 cranes that inhabit wetlands on the refuge and elsewhere in central Wisconsin during the spring and summer.
in order to establish a migratory flock of whooping cranes in the eastern United states. The Eastern Migratory Flock flies south to wetlands in the Southeast United states for the winter.
Over the past 13 years USGS biologists--dressed in costumes to avoid having the birds imprint on people--have raised between five and 20 whooping crane chicks annually that have been released into the Eastern Migratory Flock said John French leader of the USGS whooping crane
and whooping cranes in Florida this is only the second year it has been attempted with a migratory population.
or threatened bird species to the area said Doug Staller Necedah National Wildlife Refuge manager.
Necedah is the summer home for the bulk of the Eastern Migratory Flock of whooping cranes some
and provides a unique and important opportunity to learn more about these endangered birds. It was only natural for us to be involved in the parent rearing effort.
The parent-reared chicks arrived at Necedah NWR Saturday where they were housed in separate predator resistant enclosures to provide them a safe place for chicks to roost
while they acclimated to their new surroundings near other free-ranging whooping cranes. The pens are located in the vicinity of pairs of adult whooping cranes without chicks of their own.
Such pairs have a tendency to adopt other chicks and when adopted will lead them south during migration
In addition to the four parent-reared chicks released at Necedah NWR seven costumed-reared whooping crane chicks will join the eastern migratory flock this year as well.
All of the releases of whooping cranes in Wisconsin add to the Eastern Migratory Flock a reintroduction project undertaken by a broad coalition of Federal state
At one point in the past researchers believe the Whooping crane population dropped to fewer than two-dozen birds.
Every morning the cherry grower sprinkles the spores into a specially designed dispenser that has been fitted in front of the hive.
and the number of managed hives. This will help prepare Australia for the expected incursion of the Varroa mite
which is causing great damage and cost to bee and horticultural industries around the world.
#Being sheepish about climate adaptationfor thousands of years man has domesticated animals selecting the best traits possible for survival.
Now livestock such as sheep offer an intriguing animal to examine adaptation to climate change with a genetic legacy of centuries of selected breeding and a wealth of livestock genome-wide data available.
The instrument in the trunk quickly detects a large plume of methane emanating from the landfill.
A NASA aircraft soon appears overhead carrying a prototype satellite instrument that records high-resolution images of methane that scientists can use to identify gas plumes.
Creighton Litton and Susan Crow (University of Hawai`i at Manoa) and Dr. Greg Asner (Carnegie Institution for Science) shows that soil carbon storage was constant across a highly constrained 5 degrees
#Search for better biofuels microbes leads to human gutscientists have scoured cow rumens and termite guts for microbes that can efficiently break down plant cell walls for the production of next-generation biofuels
but some of the best microbial candidates actually may reside in the human lower intestine researchers report.
The human microbes appear to be endowed with enzymes that break down a complex plant fiber component more efficiently than the most efficient microbes found in the cow rumen the researchers report.
In looking for biofuels microbes in the cow rumen we found that Prevotella bryantii a bacterium that is known to efficiently break down (the plant fiber) hemicellulose gears up production of one gene more than others
In addition to finding microbes in the cow rumen and termite gut it looks like we can actually make some contributions ourselves he said.
And our bugs seem to have some enzymes that are even better than those in the cow rumen.
Story Source: The above story is provided based on materials by University of Illinois at Urbana-Champaign.
#Mown grass smell sends SOS for help in resisting insect attacksthe smell of cut grass in recent years has been identified as the plantâ##s way of signalling distress
but new research says the aroma also summons beneficial insects to the rescue. â#oewhen there is need for protection the plant signals the environment via the emission of volatile organic compounds which are recognized as a feeding queue for parasitic wasps to come to the plant that is being eaten
and lay eggs in the pest insectâ#said Dr. Michael Kolomiets Texas A&m Agrilife Research plant pathologist in College Station.
The research stems from a look at the function of a large family of lipid-derived molecular signals that regulate differential processes in humans animals and plants according to Kolomiets
The molecular signals are understood less in plants than in animals and humans he noted. â#oepeople take certain drugs such as aspirin to suppress the activity of these signals
#whether by blade of a mower or jaws of a predatory insect â#by producing defensive proteins
and secondary metabolites either to repel the pest or make itself less appetizing he said.
To test how it functions in plant during insect attacks Kolomiets and his team used a mutant corn plant that could not produce the green leaf volatiles mown-grass smell when cut or torn.
And thatâ##s when they observed that the parasitic wasps didnâ##t pay attention to plants without the green leaf volatile. â#oethere are actually two roles for this moleculeâ#he said. â#oefirst it activates the jasmonate hormone
which involves activation of defenses against insects on the plant. Then this molecule since it is a volatile attracts parasitic wasps.
They come to the plant that is being chewed up by insect herbivores and lay eggs in the caterpillarâ##s body. â#oewe have proven that
when you delete these volatiles parasitic wasps are attracted no longer to that planteven when an insect chews on the leaf.
So this volatile is required to attract parasitoids. We have provided genetic evidence that green leafy volatiles have this dual function â#in the plant they activate production of insecticidal compounds
but also they have indirect defense capability because they send an SOS-type signal that results in attraction of parasitic wasps. â#Kolomiets tested the phenomena both in the lab
and in the field. â#oewe did not have to do any artificial infestation because we had plenty of insectsâ#he said. â#oewe have discovered that even under the field conditions
when thereâ##s enough insect pressure then the plants are more susceptible to insect damage
We have found that this gene is required for many many different physiological processes such as drought toleranceâ#he said. â#oewe observed that mutant plants are drought susceptible as well as susceptible to insect feeding.
and how it works. â#Such findings may help plant breeders know how to develop new varieties that are more resistant to insects and drought he noted.
Dwindling wind may tip predator-prey balancebent and tossed by the wind a field of soybean plants presents a challenge for an Asian lady beetle on the hunt for aphids.
But what if the air--and the soybeans--were still? Rising temperatures and shifting precipitation patterns may get the lion's share of our climate change attention
but predators may want to give some thought to wind according to a University of Wisconsin Madison zoologist's study
which is among the first to demonstrate the way global stilling may alter predator-prey relationships.
There are all sorts of other things that are changing in the environment that affect animals
and plants and their interactions says Brandon Barton a UW-Madison postdoctoral researcher. My students and I were standing out in a cornfield one day as big gusts of wind came by
That's good news for hungry lady beetles according to research Barton published in the September issue of the journal Ecology.
Lady beetles eat a major soybean pest the soybean aphid. Barton grew plots of soybeans in alfalfa fields protecting some with wind blocks
He found two-thirds more lady beetles in the plots hidden from the wind and twice as many soybean aphids on the plants growing in the open.
Wind has no direct effect on the aphids tiny insects that hug the plants and anchor themselves while feeding with a needle-like mouthpart called a stylet.
The aphids appear on the plants whether it's windy or not and we showed that in lab experiments Barton says.
But when you add the predators with the wind block the beetles eat something like twice as many aphids.
In his lab trials--simulating wind with fans and windless movement with a machine that tugged on tethered plants to shake
and bend them--a stilled soybean plant represented a smorgasbord for the lady beetle. How do you do your duty as a predator if you're entire world is moving around?
says Barton whose work is funded by the National Science Foundation. If the plant is moving it takes four times as long for the predator to start eating
and it eats less than half as many aphids in an hour. Slower natural wind speeds could reduce the amount of pesticide required to keep soybean aphids from wrecking harvests.
And the wind research may present other opportunities for pest control. By growing trees or not harvesting them around a field you may be able to have an indirect effect on the number of aphids on your soybean plants says Barton who wonders what other close animal relationships may be disrupted by shifting winds.
The mechanism may be different for other predators but it's not hard to start thinking about effects he says.
Think of a wolf or coyote. Larger predators hunting by scent--and the prey trying to detect their predators--may be affected by less wind moving scents around.
Story Source: The above story is provided based on materials by University of Wisconsin-Madison. The original article was written by Chris Barncard.
Note: Materials may be edited for content and length. Journal Reference e
#Using genetic screening to improve Korean white wheatvisiting scientist Dae Wook Kim hopes to develop a line of Korean wheat that does not sprout
when exposed to wet harvest conditions thanks to genetic screening techniques he learned at South dakota State university.
He is working with molecular biologist Jai Rohila of the biology and microbiology department through a two-year project sponsored by the National Institute of Crop science in Suwaon South korea.
Paratuberculosis mainly affects ruminants and causes treatment-resistant diarrhea and wasting among affected animals. The disease can cause considerable economic losses for commercial farms.
The animals produce less milk exhibit fertility problems and are more susceptible to other conditions such as udder inflammation.
Affected animals must be reported and sacrificed. The meat of affected animals is not suitable for consumption
and must be disposed of. The disease usually manifests two to three years after the initial infection.
During this time infected animals shed the bacteria putting the health of the entire herd at risk.
and is passed to the animal's macrophages. These immune cells then migrate through the lymphatic fluid into the lymph nodes the blood and other organs.
and blood of animals suspected of being infected. First author Lorenz Khol of the Clinic for Ruminants at the Vetmeduni Vienna in cooperation with the College of Veterinary medicine at the University of Florida developed a possible alternative method for early diagnosis of the infection.
For the test Khol takes fluid from the lymph vessels at the udder of the animals.
Just a few millilitres are enough to detect the bacterium using PCR (polymerase chain reaction) in the lymph.
After one year about 70 percent of all animals which were tested positive via lymph-PCR had been culled from their herds.
These animals had developed various diseases or a reduced performance that made it necessary to remove the animals from the farm.
In comparison cows with a negative lymph result showed a 27 percent culling rate after one year only.
and the fishing industry new research links short-term reductions in growth and reproduction of marine animals off the California coast to increasing variability in the strength of coastal upwelling currents--currents that supply nutrients
Along the west coast of North america winds lift deep nutrient-rich water into sunlit surface layers fueling vast phytoplankton blooms that ultimately support fish seabirds and marine mammals.
and lower reproductive success for seabirds underscoring the importance of upwelling for the conservation of endangered animals and management of commercially important fisheries.
To study the effects of changing strength of upwelling on marine life the team integrated data on how quickly fish grew every year since the 1940s the timing of seabird egg laying since the 1970s and the fledgling success of seabirds since the 1970s.
Because the birds and fish in this study tended to rebound from each of these events within a year or two the increased variability of upwelling strength has led not to long-term declines.
Black noted that changes in upwelling strength did not affect just fish and seabirds. In a sense these representative species were just the tips of the iceberg.
By studying top level predators we get an upper level view of the entire ecosystem said Black.
Longer or shorter growing seasons influence the type of crops that are planted the pests that are present
and when animals begin feeding (either on plants or animals that eat plants) and reproducing said Schwartz who is familiar with the research
but had no role in it. In the western United states particularly water availability is affected by plants
There was a 65 per cent reduction in large seaweeds a 60 per cent reduction in other algae and invertebrates and a 40 per cent reduction in the overall number of species present.
#Peacocks train is not such a drag afterall: Flight unchanged with and without plumagethe magnificent plumage of the peacock may not be quite the sacrifice to love that it appears to be University of Leeds researchers have discovered.
Dr Graham Askew from the University's School of Biomedical sciences filmed five Indian peacocks taking off using two high-speed video cameras to try to work out
what price male birds pay for carrying the spectacular iridescent feathers they use in displays to attract females.
These feathers weigh about 300g and can exceed 1. 5m so it's expected that the male birds would be making a significant sacrifice in their flight performance for being attractive--possibly giving up their lives
if the train restricts escape from predators such as tigers and leopards in their natural environment Dr Askew said.
He filmed the take-offs of birds carrying full plumage in 3d and then filmed the same birds taking off without their trains.
The display feathers which naturally moult at the end of the breeding season were cropped to judge the change in take off performance between the two states.
To his surprise Dr Askew found there was no significant difference. Dr Askew observed the position of each bird's centre of mass their wing motions
and the movement of the train in take off and then calculated the amount of power used by the birds to accelerate
and gain height over the first two wing beats. He found it was essentially the same regardless of the presence or absence of the train.
Intuitively you expect that the train would detrimentally affect flight performance and so not finding a detectable effect was a bit surprising Dr Askew said.
These birds do not seem to be making quite the sacrifices to look attractive we thought they were.
He added: The train of the peacock is one of the most iconic examples of sexual selection in the animal kingdom.
It has been thought that such elaborate ornamentation carries a functional cost for the bearer. These results therefore have broader ramifications for evolutionary biology's understanding of sexual selection.
Although the drag doubled overcoming that drag is only a tiny part of the power used by the birds during take off.
Therefore the impact of the train on the overall take off performance is negligible allowing birds with
The results do not mean that having an ornate train carries no costs for peacocks.
Dr Askew pointed out that the feathers might adversely affect flight stability and the birds'ability to run.
Just creating the ornate plumage is a costly exercise; male birds invest about 3%of their daily metabolic energy budget in train growth.
Story Source: The above story is provided based on materials by University of Leeds. Note: Materials may be edited for content and length.
which the animal was painted always black or in reddish tones. We were also able to establish that it is very closely related to today's Iberian pig species and specifically to the'Lampiã o del Guadiana'strain.
which are very rare or absent in wild boars (the precursor animals to the domestic pig);
which are presumably the descendents of the animals Spanish colonizers brought to America. Researchers demonstrate that this hypothesis is incorrect
and that there is very little remaining of those first Spanish animals in today's creole pigs
which their research has found to be the victim of herbivorous Sesarma purple marsh crabs run amok.
Recreational fishing has depleted the crab's predators Bertness said resulting in die off where recreational fishing is prominent.
But in some places the grasses have been growing back in in part thanks to the invasion of a new predator of Sesarma.
when you have one of these predator-depletion-triggered die offs is that you lose a lot of the positive feedbacks
Regionally this species can be a serious agricultural pest; however it appears to reach its distributional limits in extremely cold or hot areas.
Together with her colleague from GÃ rlitz Dr. John M. C. Hutchinson and a colleague from the United states Department of agriculture (USDA-APHIS) the scientist has studied the distribution of these mollusks
These new habitats created by humans open new paths for the expansion of the slugs into areas that are normally inhospitable for animals
In principle all areas with a temperate climate can serve as potential habitat for these animals says Hutchinson and offers the following recommendation:
But growers outside the U s. should also focus on developing an integrated management program that considers factors such as optimum planting dates plant densities and pest management.
and made way for the rise of the mammals. But what happened to the plants on which the dinosaurs fed?
and totally eco-friendly sound and odor devices to fight off insects from their cultivated fields.
These areas are an important resource for pollinators and it now seems they even have an impact on the yield of the cultivated crops.
The European grape berry moth and the cicada Scaphoideus titanus are considered to be the major pests of cultivated grape.
or plant growing regulators to protect their crops against pests and diseases. But used in a wrong way pesticides can pose a risk to humans and the surrounding environment.
At the Fondazione Edmund Mach in Italy Ilaria Pertot and her team of the EU research project PURE have found ways to reduce the high pesticide rate in the European grapevine sector by disturbing the mating processes of the pests.
The use of special vibrations and the odor of pheromones will in future help to prevent an offspring of the pests
Camilla Moonen and her team focus on natural pollinators like the wild bee. In experiments they are investigating
whether natural pollinators contribute a higher yield quality. Both of these studies have shown that modern agriculture can still learn from nature
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