When threatened by bees elephants shake their heads in an effort to knock the insects away as well as running
and communicate about honeybees and humans is being used to reduce human-elephant conflict in Kenya.
and Save the Elephants have built scores of'beehive fences'around local farms that protect precious fields from crop-raiding elephants.'
And the bark beetle is putting spruces all over Switzerland under increasing pressure because an additional generation of pests could hatch each year due to the rising temperatures.
and comes under increased pressure from bark beetles. This also reduces the protective effect against avalanches and rockfalls.
#Success of new bug-fighting approach may vary from field to fielda new technique to fight crop insect pests may affect different insect populations differently researchers report.
They analyzed RNA interference (RNAI) a method that uses genetic material to silence specific genes--in this case genes known to give insect pests an advantage.
-Ching Chu entomology research associate Weilin Sun Illinois Natural history Survey insect behaviorist Joseph Spencer and U. of I. entomology professor Barry Pittendrigh.
Controlling the western corn rootworm costs growers more than $1 billion a year in the U s. Current methods for keeping the bug in check--crop rotation
They found that microbes in the guts of rotation-resistant rootworms help those beetles that stray into soybean fields survive on soybean leaves for a few days--just long enough for the females to lay their eggs in soil that will be planted in corn the following year.
Rather than studying a laboratory population of insects in the new analysis the team tested RNAI on rootworm beetles collected from fields in three locations in the Midwest--two in Illinois with established rotation-resistant populations
After generations in the laboratory insects gradually lose their natural diversity Seufferheld said. This makes it easier to control them
and may not accurately reflect actual insect responses in the field he said. Seufferheld now works for Monsanto and is based in Buenos aires where he is in charge of insect resistance management.
The team targeted two genes that are regulated differently in rotation-resistant and non-resistant rootworms. The first Dvrs5 codes for an enzyme that helps the rootworms digest plant proteins.
The second att 1 aids in the insects'immune response. These genes have been found to play a role in rootworm resistance to crop rotation.
(which involves feeding it to the bugs) influenced enzyme activity in the rootworm gut. They also recorded how long the beetles survived on soybean leaves after ingesting RNAI.
As expected the RNAI targeting Dvrs5 reduced that enzyme's activity in all three rootworm populations.
But the treatment had less of an effect on rotation-resistant beetles (activity dropped to about 48 percent) than on their nonresistant counterparts (enzyme activity dropped to 24 percent.
But the study does offer important insights into the complexity of insect biology Seufferheld said.
and the insects that feed on those crops this knowledge will help us develop better pest-management strategies that are more in tune with nature.
This is important evidence that insect populations vary in their response to RNAI and might be influenced by other selective events Pittendrigh said.
Although insect-eating bats have been shown to avoid foraging in light-polluted areas this is the first study to show that fruit-eating bats also avoid lit areas.
Woodland salamanders facilitate the capture of this carbon before it is released by feeding on invertebrates (beetles earthworms snails ants etc.
#Predators delay pest resistance to Bt cropscrops genetically modified with the bacterium Bt (Bacillus thuringiensis) produce proteins that kill pest insects.
Cornell research shows that the combination of natural enemies such as ladybeetles with Bt crops delays a pestâ##s ability to evolve resistance to these insecticidal proteins. â#oethis is demonstrated the first example of a predator being able
to delay the evolution of resistance in an insect pest to a Bt cropâ#said Anthony Shelton a professor of entomology at Cornell University's New york state Agricultural Experiment Station in Geneva N y
Bt is a soil bacterium that produces proteins that are toxic to some species of caterpillars
and beetles when they are ingested but have been proven safe to humans and many natural enemies including predaceous ladybirds.
Bt genes have been engineered into a variety of crops to control insect pests. Since farmers began planting Bt crops in 1996 with 70 million hectares planted in the United states in 2012 there have been only three clear-cut cases in agriculture of resistance in caterpillars
and one in a beetle. â#oeresistance to Bt crops is said surprisingly uncommonâ Shelton. To delay or prevent insect pests from evolving resistance to Bt crops the U s. Environmental protection agency promotes the use of multiple Bt genes in plants
and the practice of growing refuges of non-Bt plants that serve as a reservoir for insects with Bt susceptible genes. â#oeour paper argues there is another factor involved:
the conservation of natural enemies of the pest speciesâ#said Shelton. These predators can reduce the number of potentially resistant individuals in a pest population and delay evolution of resistance to Bt.
In the study the researchers set up large cages in a greenhouse. Each cage contained Bt broccoli and refuges of non-Bt broccoli.
They studied populations of diamondback moth (Plutella xylostella) larvae a pest of broccoli and their natural enemies ladybird beetles (Coleomegilla maculata) for six generations.
The results showed that diamondback moth populations were reduced in the treatment containing ladybird beetles and unsprayed non-Bt refuge plants.
In contrast Bt plants with no refuge were defoliated completely in treatments without ladybirds after only four to five generations showing rapid development of resistance in the pests.
and predators diamondback moth populations were reduced but the larvae more quickly evolved resistance to the Bt plants. â#oethese results demonstrate the effectiveness of Bt plants in controlling the pest population the lack of effect of Bt on the predators
The BEEHAVE model published today in the Journal of Applied Ecology was created to investigate the losses of honeybee colonies that have been reported in recent years
and to identify the best course of action for improving honeybee health. A team of scientists led by Professor Juliet Osborne from the Environment and Sustainability Institute University of Exeter (and previously at Rothamsted Research) developed BEEHAVE
which simulates the life of a colony including the queen's egg laying brood care by nurse bees
To build the simulation the scientists brought together existing honeybee research and data to develop a new model that integrated processes occurring inside and outside the hive.
The first results of the model show that colonies infested with a common parasitic mite (varroa) can be much more vulnerable to food shortages.
BEEHAVE simulations show that good food sources close to the hive will make a real difference to the colony
Addressing forage availability is critical to maintaining healthy hives and colonies over the long term. Professor Osborne added:
Professor Osborne's research group studies the behaviour and ecology of bees and other pollinators.
This virtual hive is an important new research tool to help us understand how changes to the environment impact on bee health.
and beekeeping practices will benefit honeybees the most. Dr David Aston President of The british Beekeepers Association commented that:
a highly specialized species of tephritid fruit fly whose larvae actually feed on the seeds of the native Barberry was found to have a tenfold higher population density on its new host plant the Oregon grape reports Dr. Harald Auge a biologist at the UFZ.
and then cut open to examine any infestation by the larvae of the tephritid fruit fly (Rhagoletis meigenii).
If the larva is able to develop it will often feed on all of the seeds in the berry.
This mechanism is employed also to defend it from the tephritid fruit fly. If a seed is infested with the parasite later on the developing larva will feed on both seeds.
If however the plant aborts the infested seed then the parasite in that seed will also die
Instead it appears to'speculate'that the larva could die naturally which is a possibility.
But how does the Barberry know what is in store for it after the tephritid fruit fly has punctured a berry?
The Oregon grape that is closely related to the Barberry has been living in Europe for some 200 years with the risk of being infested by the tephritid fruit fly
Dung beetles recount the nature of the pastthe biologists behind the new research findings synthesized decades of studies on fossil beetles focusing on beetles associated with the dung of large animals in the past or with woodlands and trees.
Their findings reveal that dung beetles were much more frequent in the previous interglacial period (from 132000 to 110000 years ago) compared with the early Holocene (the present interglacial period before agriculture from 10000 to 5000 years ago.
One of the surprising results is that woodland beetles were much less dominant in the previous interglacial period than in the early Holocene
The composition of the beetles in the fossil sites tells us that the proportion and number of the wild large animals declined after the appearance of modern man.
Another danger of a more homogeneous global food basket is that it makes agriculture more vulnerable to major threats like drought insect pests and diseases
pesticidesresistance to pesticides has now been recorded in nearly a thousand pest species including more than 500 insects 218 weeds and 190 fungi that attack plants.
The recorded cases of resistance in insects mites and other arthropods which include resistance to multiple pesticides per species more than doubled from 5141 in 1990 to 11254 in 2013.
and managing insect resistance to corn and cotton plants genetically engineered to produce proteins from the bacterium Bacillus thuringiensis (Bt).
but are not toxic to people wildlife or even most insects. Organic growers have used Bt toxins in sprays for decades
The cost of this insidious beetle to U s. corn growers has been estimated at one billion dollars annually.
Noting that insects have been evolving resistance to natural plant defenses for millions of years and that this year marks the 100th anniversary of the first reported case of insecticide resistance he concludes Finding ways to delay resistance is a never-ending challenge with any pest management approach.
Flowers attract pollinators fruits attract seed-dispersing animals plants express stress responses and organisms communicate with each other in many ways via color.
Lake Eyre dragon lizards Ctenophorus maculosus are found exclusively in salt deserts in southern Australia where they feed on dead insects blown onto the salt crust.
and Plant Health Inspection Services (APHIS) and the Wildlife Conservation Society (WCS) demonstrates that it is possible to qualify bison coming from an infected herd as free of brucellosis using quarantine procedures.
In response to Interagency Bison Management Plan (IBMP) guidelines on federal and state bison management actions the USDA APHIS Brucellosis Eradication:
Rhyan APHIS Veterinary Officer. Additionally this study was a great example of the benefits to be gained from several agencies pooling resources
and insect fossils suggesting the Bering land bridge wasn't just barren grassy tundra steppe
#Controlling zebra chip disease from the inside outzebra chip disease in potatoes is currently being managed by controlling the potato psyllid with insecticides.
which is transmitted by the psyllid said Dr. Ron French Agrilife Extension plant pathologist in Amarillo.
Biological control methods can target psyllid populations in a field but it takes a while for them to be effective
and by then the insect has transmitted already the bacterium into the plant especially if that psyllid flew into the field.
It only takes a few hours for a psyllid to acquire and transmit the bacterium from plant to plant French said.
French is conducting his studies using alternative controls as a part of the U s. Department of agriculture-National Institute of Food
so that any negative impacts the psyllid bacterium disease or pesticide use are having on the plant can translate into improved yields.
when psyllid populations in the field and the instances of zebra chip were said significant French.
and the psyllid as well he said. We hope to be able to do laboratory studies to determine
Year after year there are differences in the field as far as climate disease pressure insect pressure--so sometimes we have to go to the lab to figure out why it works one time and not another.
The third and last approach he is studying is using plant nutrients to offset the damage caused by the psyllid
but that does not take into account foliar symptoms potential insect damage and other yield-limiting factors he said.
and is transmitted by the citrus psyllid. After several years of work French said his studies are beginning to raise more interest from the industry to get products labeled or at least tested.
New and improved varieties of cowpeas have numerous adaptive traits of agronomic importance such as 60-70 day maturity drought tolerance heat tolerance aphid resistance
and heat tolerant genes but also develop a platform for mapping genes controlling several other biotic and abiotic stress tolerances such as aphid resistance and low phosphorus tolerance both
and using antibiotics in hives to keep the bees disease-free. To help regulate honey safety We have strict import laws that apply to honey coming from certain countries he says.
and hives Bryant contends. That in turn will greatly increase the cost of food. The result might be oranges
#Characterization of stink bug saliva proteins opens door to controlling pestsbrown marmorated stink bugs cause millions of dollars in crop losses across the United states because of the damage their saliva does to plant tissues.
Researchers at Penn State have developed methods to extract the insect saliva and identify the major protein components which could lead to new pest control approaches.
Until now essentially nothing was known about the composition of stink bug saliva which is surprising given the importance of these insects as pests
By identifying the major protein components of saliva it now may be possible to target the specific factors in saliva that are essential for their feeding and therefore design new approaches for controlling stink bugs.
According to Felton stink bugs produce two types of saliva that are required for successful feeding. Watery saliva helps stink bugs to digest their food.
Sheath saliva surrounds stink bugs'mouthparts and hardens to prevent spillage of sap during feeding.
when the insect is finished feeding. Unlike a chewing insect which causes damage by removing plant tissue stink bugs pierce plant tissue
and suck nutrients from the plant said Michelle Peiffer research support assistant. During this process stink bugs also deposit saliva onto the plant.
The interaction between this saliva and the plant is what causes the cosmetic and physiological changes that make crops unmarketable.
and Peiffer first collected adult bugs from homes and fields in central Pennsylvania and maintained them in their laboratory.
The researchers chilled the insects on ice. As the insects returned to room temperature their watery saliva was secreted from the tips of their beaks.
The team collected this saliva processed it and analyzed it for protein content. To collect sheath saliva the scientists placed organic grape tomatoes in the cages.
After two days of stink bug feeding they removed the tomatoes from the cages and used forceps to extract the hardened sheaths from the surfaces of the tomatoes.
These results reveal that the protein composition of the sheath is a mixture of insect
but rather it represents the natural coalescing of insect -and plant-derived proteins that occurs during formation of the sheath and subsequent feeding.
and to analyze the proteins should be generally applicable for any species of stink bug.
#Sterile flies save food crops, millions of dollars in eradication effortsirradiated sterile flies dropped over seaports
But blasting these secret-suitor insects with radiation via electron beams X-rays or gamma-rays tends to make them weaker than typical males
What sterile-insect operations need says University of Florida insect physiologist Daniel Hahn is the insect world's version of George Clooney:
and last that sterilizing insects in a low-oxygen environment helps create suitors who more closely resemble the suave Clooney than do sterilized those in a normal-oxygen environment.
Our males (insects) are not only more sexually competitive they are maintaining their sexual competitiveness and their virility into old age Hahn said
The sterile insect technique or SIT has been used for decades and is considered a much preferable alternative to spraying pesticides over urban or suburban areas near major ports.
In this biological control method large numbers of sterile male insects are released to compete with wild males for the attention of invasive wild females.
The technique has been used effectively against the Mediterranean fruit fly called the Medfly and the cattle-infesting screw-worm fly among others.
Florida spends roughly $6 million a year using SIT to prevent Mediterranean fruit fly infestations while California spends about $17 million a year.
Because of the inherent dangers in importing even one Mediterranean fruit fly into the state in their recent studies LÃ pez-Martã nez and Hahn investigated the physiological effects of applying low-oxygen treatments prior
the Caribbean fruit fly and the invasive cactus moth. The low-oxygen effect has been known for decades
They suspected and found that under the low-oxygen conditions the insects'cells would produce antioxidants that can help better protect them from the off-target radiation damage.
Some operations that rear and sterilize insects such as one in Guatemala that produces many of the sterile medflies dropped over Florida's major ports roughly every seven days do employ low-oxygen conditions called hypoxia or anoxia.
and sterilize the cactus moth. The reseachers found using a low-oxygen environment during sterilization boosted the sterile males'longevity as well as their ability to attract and successfully mate.
They found that the positive effects of low-oxygen treatments even extended into their'old age'--in the insects'case about 30 days under cushy laboratory conditions.
#Moths trapped with plant-produced sex pheromonea collaborative experiment involving a Kansas State university biochemist may mark the beginning of an effective environmentally friendly plant-based method of insect control.
and moth enzymes to engineer plants that emitted sex pheromones that mimic those naturally produced by two species of moths.
The research recently appeared in the journal Nature Communications A plant factory for moth pheromone production.
and insects that are used to attract mates or relay danger. Currently insect pests are managed with pesticides and synthetic pheromones--the latter
of which confuse the insect and prevent it from breeding or enable it to be trapped. While these pheromones can be made chemically it can be a toxic process to produce them Durrett said.
What we demonstrated in this study is a more environmentally friendly approach that avoids the need to use toxic chemicals
The study focused on the bird-cherry ermine moth and the orchard ermine moth--two insects that feed on the leaves of orchard trees
and as caterpillars can strip trees of their bark. Durrett helped the Swedish researchers use enzymes from plants
and moths to create a biological pathway that made it possible for plants to produce the moths'sex pheromones.
He contributed an enzyme from the burning bush plant that performed the final step in the synthesis process essentially turning plants into pheromone production factories.
The result was plants that produced pheromones that mimicked the sex pheromones of both moth species. The Swedish researchers baited moth traps with the plant-produced pheromone.
They found that each trap attracted an average of 130 male moths--half the number of catches possible with synthetic pheromones
While a proof-of-concept experiment engineering plants to be insect pheromone-producing factories creates an environmentally friendly alternative to pesticides as well as an easier
and less expensive method of synthesizing insect pheromones Durrett said. None of the enzymes that were put together would interact with each other naturally so it was really exciting to see this pathway work
#Genetic secret of mosquito resistance to DDT, bed net insecticides discoveredresearchers from LSTM have found that a single genetic mutation causes resistance to DDT
The researchers led by Dr Charles Wondji used a wide range of methods to narrow down how the resistance works finding a single mutation in the GSTE2 gene which makes insects break down DDT
They have shown also that this gene makes insects resistant to pyrethroids raising the concern that GSTE2 gene could protect mosquitoes against the major insecticides used in public health.
Mosquitoes (Anopheles funestus) are vectors of malaria and most strategies for combating the spread of the disease focus on control of mosquito populations using insecticides.
The spread of resistance genes could hold back efforts to prevent the disease. The authors say that knowing how resistance works will help to develop tests
and stop these genes from spreading amongst mosquito populations. Charles Wondji said:''We found a population of mosquitoes fully resistant to DDT (no mortality
when they were treated with DDT) but also to pyrethroids. So we wanted to elucidate the molecular basis of that resistance in the population
'They took mosquitoes from Pahou in Benin which were resistant to DDT and pyrethroids and mosquitoes from a laboratory fully susceptible strain and did a genome wide comparison study.
They identified the GSTE2 gene as being upregulated--producing a lot of protein--in Benin mosquitoes. They found that a single mutation (L119f) changed a non-resistant version of the GSTE2 gene to a DDT resistant version.
They designed a DNA-based diagnostic test for this type of resistance (metabolic resistance) and confirmed that this mutation was found in mosquitoes from other areas of the world with DDT resistance
but was completely absent in regions without. X-ray crystallography of the protein coded by the gene illustrated exactly how the mutation conferred resistance by opening up the'active site'where DDT molecules bind to the protein so more can be broken down.
This means that the mosquito can survive by breaking down the poison into nontoxic substances..
They also introduced the gene into fruit flies (Drosophila melanogaster) and found they became resistant to DDT
and pyrethroids compared to controls confirming that just this single mutation is enough to make mosquitoes resistant to both DDT and permethrin.
'For the first time we have been able to identify a molecular marker for metabolic resistance (the type of resistance most likely to lead to control failure) in a mosquito population
#As hubs for bees, pollinators, flowers may be crucial in disease transmissionlike a kindergarten or a busy airport where cold viruses and other germs circulate freely flowers are common gathering places where pollinators such as bees
and butterflies can pick up fungal bacterial or viral infections that might be as benign as the sniffles
or as debilitating as influenza. But almost nothing is known regarding how pathogens of pollinators are transmitted at flowers postdoctoral researcher Scott Mcart
and Professor Lynn Adler at the University of Massachusetts Amherst write. As major hubs of plant-animal interactions throughout the world flowers are ideal venues for the transmission of microbes among plants and animals.
As the authors point out Given recent concerns about pollinator declines caused in part by pathogens the role of floral traits in mediating pathogen transmission is a key area for further research.
They say their synthesis could help efforts to control economically devastating pollinator-vectored plant pathogens such as fire blight
Traditionally research on flower evolution has focused largely on selection by pollinators but as Mcart and colleagues point out pollinators that also transmit pathogens may reduce the benefits to the plant of attracting them depending on the costs and benefits of pollination.
The researchers say more work is needed before scientists can know whether a flower's chemical or physical traits determine the likelihood that pathogens are transmitted for example
and whether infection by pathogens is an inevitable consequence of pollinator visitation. Plant pathologists have made great strides in identifying floral traits that mediate host plant resistance to floral pathogens in individual systems;
From the pollinator's perspective there has been surprisingly little work elucidating the role of flowers and floral traits for pathogen transmission.
Given recent concerns about pollinator declines caused in part by pathogens understanding the role of floral traits in disease transmission is a key missing element say Mcart and colleagues.
In many creatures'eyes visual cells are distributed evenly in an obvious pattern such as the familiar hexagonal compact eyes of insects.
and mongoose lemurs that eat a mix of fruit leaves seeds flowers nectar and insects.
#Managed honeybees linked to new diseases in wild bees, UK study showsdiseases that are managed common in honeybee colonies are now widespread in the UK's wild bumblebees according to research published in Nature.
The study suggests that some diseases are being driven into wild bumblebee populations from managed honeybees.
Dr Matthias FÃ rst and Professor Mark Brown from Royal Holloway University of London (who worked in collaboration with Dr Dino Mcmahon
and Professor Robert Paxton at Queen's university Belfast and Professor Juliet Osborne working at Rothamsted Research and the University of Exeter) say the research provides vital information for beekeepers across the world to ensure honeybee management
This research assessed common honeybee diseases to determine if they could pass from honeybees to bumblebees.
It showed that deformed wing virus (DWV) and the fungal parasite Nosema ceranae--both of which have major negative impacts on honeybee health--can infect worker bumblebees
and in the case of DWV reduce their lifespan. Honeybees and bumblebees were collected then from 26 sites across the UK
and screened for the presence of the parasites. Both parasites were widespread in bumblebees and honeybees across the UK.
Dr FÃ rst explained: One of the novel aspects of our study is that we show that deformed wing virus
which is one of the main causes of honeybee deaths worldwide is not only broadly present in bumblebees
and studied genetic similarities between DWV in different pollinator populations. Three factors suggest that honeybees are spreading the parasites into wild bumblebees:
honeybees have higher background levels of the virus and the fungus than bumblebees; bumblebee infection is predicted by patterns of honeybee infection;
and honeybees and bumblebees at the same sites share genetic strains of DWV. We have known for a long time that parasites are behind declines in honeybees said Professor Brown.
What our data show is that these same pathogens are circulating widely across our wild
and managed pollinators. Infected honeybees can leave traces of disease like a fungal spore or virus particle on the flowers that they visit and these may then infect wild bees.
While recent studies have provided anecdotal reports of the presence of honeybee parasites in other pollinators this is the first study to determine the epidemiology of these parasites across the landscape.
The results suggest an urgent need for management recommendations to reduce the threat of emerging diseases to our wild
and managed bees. Professor Brown added: National societies and agencies both in the UK and globally currently manage so-called honeybee diseases on the basis that they are a threat only to honeybees.
While they are doing great work our research shows that this premise is not true
and that the picture is much more complex. Policies to manage these diseases need to take into account threats to wild pollinators
and be designed to reduce the impact of these diseases not just on managed honeybees but on our wild bumblebees too.
Story Source: The above story is provided based on materials by Biotechnology and Biological sciences Research Council. Note:
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