Showing posts with label Research and Studies. Show all posts
Pesticides Confuse Bees : Study Suggests
Posted by Unknown in Beekeeping, Honey Bee, Pesticide, Research and Studies on Tuesday, 14 May 2013
John von Radowitz, PA
Times of Malta
 |
| Insecticides disrupt their learning, threatening survival and reducing pollination |
Commonly used pesticides confuse bees by disrupting the learning circuits in their brains, a study has found.
The effects
could make it harder for bees to forage among flowers for food, thereby
threatening their survival and reducing pollination.
Bees exposed to
two kinds of pesticide were slower to learn or completely forgot
important associations between floral scents and nectar.
The impact of the chemicals increased when they were combined together.
One group of
compounds tested were neonicotinoids, which are related to nicotine and
used around the world to control a variety of pests. The other
pesticide, coumaphos, is employed outside the EU to kill the Varroa mite
that attacks honeybees.
In the laboratory, scientists exposed bees’ brains to levels of the pesticides similar to those found in the wild.
They then
recorded electrical activity from cells from a higher order bee brain
structure called the ‘mushroom body’ which is important for memory and
learning. Forty per cent of a bees’ neurons can be found in the mushroom
bodies.
The results showed that both chemicals targeted this region of the bee brain, causing a loss of function.
Other research
by collaborating scientists showed that up to 30 per cent of honeybees
exposed to combinations of the pesticides for four days failed to learn
and performed poorly in memory tests.
The findings are published in the journal Nature Communications.
Geraldine
Wright, from the University of Newcastle, said: “Pollinators perform
sophisticated behaviours while foraging that require them to learn and
remember floral traits associated with food. Disruption in this
important function has profound implications for honeybee colony
survival, because bees that cannot learn will not be able to find food.”
Christopher
Connelly, whose team at the University of Dundee conducted the brain
recordings, said: “Much discussion of the risks posed by the
neonicotinoid insecticides has raised important questions of their
suitability for use in our environment.
However, little
consideration has been given to the miticidal pesticides introduced
directly into honeybee hives to protect the bees from the Varroa mite.
We find that both have negative impact on honeybee brain function.
“Together,
these studies highlight potential dangers to pollinators of continued
exposure to pesticides that target the insect nervous system and the
importance of identifying combinations of pesticides that could
profoundly impact pollinator survival.”
Bee expert
Francis Ratnieks, professor of apiculture at the University of Sussex,
said: “Bees are wonderful creatures in their own right, and are of
increasing importance to our own food supply through pollination. This
makes it extremely important that we understand what affects their
health and causes declines in their populations.
“It’s no
surprise that insecticides at high concentrations are harmful, but we
don’t know whether the low levels of neonicotinoid insecticides in the
nectar and pollen of treated plants, such as oil seed rape, are harmful
in the real world.
“This new
research gives us basic knowledge of how these insecticides affect
specific cells in the honeybee brain that play a role in honeybee
learning and behaviour.”
Reduced numbers
of flowers and wildlife habitats due to the intensification of farming
was probably the most important factor behind bee loss.
Ratnieks added that coumaphos could not legally be used to control Varroa mites in the UK and EU.
Wheat Disease Threatens Global Food Supplies
Posted by Unknown in Plant Diseases, Research and Studies, Wheat on Sunday, 12 May 2013
By Miriam Hall
An
international team of researchers has warned that a destructive wheat
disease could threaten global food security and is calling for a
doubling in funding to develop disease-resistant varieties.
Wheat stem rust - also known as UG99 - is an aggressive fungus and one of the most destructive wheat diseases.
It was first found in Uganda, but has spread through the Middle East, destroying wheat crops.
CSIRO scientist Darren Kriticos
- who authored a report about how to keep ahead of the disease - says
the wheat industry has been protected so far by developing resistant
varieties.
He says wheat
stem rust is a global problem and unless there is a long-term plan,
wheat-producing countries - including Australia - will be at risk.
"It's headed for Australia. It's not a matter of if it gets to Australia, it's a matter of when," he said.
"So it's
imperative for Australia's wheat production and wheat production
security to ensure that we have varieties of wheat that are resistant."
Mr Kriticos
wants wheat-producing countries around the world to collectively invest
$50 million a year to research new ways to protect crops.
"If that investment isn't made we're going to run into problems," he said.
"There will be outbreaks of new emerging strands so this isn't a problem that we can fix with a one-off investment."
Professor of Applied Economics at the University of Minnesota Phil Pardey agrees that a long-term approach is needed.
"It's not just getting the investments right today; it's keeping them right that's the problem," he said.
"It's trying to
get that policy message across that whilst Australia might be carrying
its fair share globally, we certainly indicate that research in this
area needs to double.
"And if you don't, the natural consequences are you expose yourself to a much higher risk of crop failures."
He says agricultural research and development is not often in the spotlight.
"They're not probably particularly sexy to most people in thinking about [research and development]," he said.
"But when you
start paying more for your food at the supermarket, you start to notice.
We've seen a major increase in food commodity prices in the last five
to 10 years.
"What happens
in terms of your food bill on a week-to-week basis at a supermarket
directly relates back to the amounts and types of investments in
[research and development]."
Farmer Bruce Schwartz - who has grown wheat for decades - has seen first-hand how damaging crop diseases can be.
"The disease problems that we do have change with the seasons," he said.
"They can be really bad one year and not so bad the next."
He keeps a close watch on new varieties as a way of protecting his wheat.
"A lot of money goes into research and development," he said.
"They're trying
really hard to find remedies for all these diseases but every time they
think they've nearly got there, something else pops up."
The paper warning about the threat of wheat stem rust was published in the journal Science today.
Poultry Litter Not Responsible for Weed Surge
Posted by Unknown in Bedding and Litter, Poultry, Research and Studies, Weed, Weed Control on Friday, 29 March 2013
You don’t catch a cold from cold weather. Rubbing a corn kernel on a wart and then burying it under the doorstep will not make the wart dry up. And you don’t get weeds in your fields from applying poultry litter.
At least that’s what the little research currently available shows.
“We don’t have a lot of research on whether applying poultry litter to cropland increases weed pressure,” says Joseph Payne, Oklahoma State University Extension livestock specialist.
Payne, speaking during a weed management session at the annual No-Till Oklahoma Conference yesterday in Norman, said research as far back as 1934 indicates that poultry litter carries almost no weed seed.
A study back then indicated that only about 0.02 percent of seeds fed to chickens were viable in the poultry litter.
“It’s a real challenge to get a seed to survive a chicken’s digestive system,” Payne said. “The gizzard grinds everything up.” Also, chickens eat pelletized rations, which are heated to the point that weed seed would not remain viable.
“So we should not see weed seed in poultry litter.” Still, Payne gets questions from farmers who have noticed a “flurry of weed growth,” following application of chicken litter. “Ís chicken litter the source?”
More recent research indicates it’s highly unlikely. Payne said a study at N.C. State University in 1995 tested poultry litter products. Products that were fumigated before application showed no weed seed germination. Products that were not fumigated showed numerous weeds. Consequently, one might assume that the poultry litter did carry weed seed.
Not so fast. The study also looked at commercial fertilizer products. Products that were fumigated before application showed no weed growth. Products not fumigated showed “numerous weeds.”
The fumigation, not the nutrient, was the difference, Payne said.
Another study at Auburn University using sterile potting mix with the poultry litter came to the same conclusion. “Poultry litter is not a source of weed seed.”
What happens, Payne says, is that nutrition, whether biological or commercial, stimulates weed growth.
The litter does have value, he added. A litter product with an analysis of 63-61-50 includes $26 worth of nitrogen, $26 worth of phosphorus and $23 worth of potassium per ton. Add $2 for liming value and the total value is $77 per ton.
Payne said he would not pay that for poultry litter but would buy commercial fertilizer if nutrients were deficient. At a lower price, $40 per ton, poultry litter might be a better value.
“But remember, nutrients only have value if there is a deficiency in the soil.”
And that’s not chicken feed.
Thoroughbred Race Horses All Traced to One 17th-Century Mare
Posted by Unknown in Genetics, Horse and Equine, Research and Studies, UK on Tuesday, 29 January 2013
(ABC News)
All the great names in thoroughbred horse racing — from Secretariat to
Man O’War, from Seabiscuit to Seattle Slew — they’re all related, and a
team of geneticists has now traced their talent for speed back to a
single ancestor. The “speed gene” that made them all so fast was
apparently a genetic aberration, and it probably started with one
British mare who lived in the mid-17th century.
Emmeline
Hill of University College Dublin led a team that analyzed DNA in 593
horses from 22 modern breeds, as well as museum specimens from 12
historically famous stallions. Modern genetics have become sophisticated
enough that they could tell, with considerable precision, what the
horses had in common.
“The
results show that the ‘speed gene’ entered the thoroughbred from a
single founder, which was most likely a British mare about 300 years ago
when local British horse types were the pre-eminent racing horses,
prior to the formal foundation of the thoroughbred racehorse,” said Hill
in a prepared statement.
She and her colleagues published their findings in the journal Nature Communications.
Lest
this seem like some arcane animal study, it does involve a big-money
sport and, more important, questions about how genetic characteristics
can be inherited and traced. If you can decipher the genes that make
thoroughbreds so fast, say the researchers, you can also find clues to
genetic diseases in people. Thoroughbred horses are useful for study
because the records of their ancestry are — forgive the pun — really,
really thorough, going back centuries.
The
great speed horses all shared two genes associated with muscle
development. The combination did not show up in regular farm horses, or
donkeys, or zebras.
Horses
with the two genes were consistently top sprinters. It’s no accident
that the Kentucky Derby is a mile and a quarter, usually won in just
more than two minutes. Other genetic combinations were found in horses
that were slower but able to run longer.
Place your bets.
Researchers Aim to Flick The High-Carbon Switch on Rice
Posted by Unknown in Genetics, Research and Studies, Rice on Monday, 28 January 2013
'C4 photosynthesis', as used by maize and sorghum, could greatly boost rice yields, after a decade of slowing improvements.
Codename: C4
rice project. Mission: to modify photosynthesis in rice to boost crop
yields. Duration: 15 to 25 years. This might sound like science fiction,
but it is already under way at the International Rice Research
Institute (IRRI) in
the Philippines, where William Paul Quick and his team have been working
since 2008 on changing the photosynthesis process in rice from the C3
carbon-fixation mechanism, common to 98% of all plants, to its much more
efficient C4 counterpart.
Some 50
species, including maize and sorghum, have completed this step
naturally, enabling the plants to devote most of their energy to
carbon-fixing, and thus to growth. "At present we are studying how far
the cell structures and enzymes required to achieve C4-type
photosynthesis are already present in rice and closely related plants,"
says Nourollah Ahmadi, a rice specialist at France's Centre for International Co-operation on Farming Research for Development. "The
aim is to activate the available but as yet inactive cell structures
and enzymes and to introduce the ones that are lacking by genetic
transformation, drawing on other plants."
This could
increase output by as much as 50%, bringing about another green
revolution, capable of responding to the foreseeable demand for food in
2050, when there will be 9 billion mouths to feed. Rice is currently the
staple foodstuff for more half the world's population, with more than 1
billion people depending on rice farming for their livelihoods. "For
every additional billion people, an extra 100m tonnes of rice will need
to be produced," says Ahmadi. In contrast, the annual increase in yields
has slowed since the 1990s, from 2% to just 1%.
Research into
rice now concentrates on creating varieties that are more productive and
more resistant to the various forms of stress, caused by disease (such
as pyriculiariosis) or environmental factors (flooding, drought, extreme
temperatures and high salt concentrations).
"Rice will be
one of the cereals most affected by climate change," says Robert
Zeigler, the head of IRRI. "So it's vital to prepare production systems
and rice growers for change if we want to maintain a certain dynamic."
Hopes are consequently high for the programme launched by IRRI and China
to sequence the genome of 10,000 of the 120,000 known rice varieties.
The first results are due in June.
"Thanks to new
sequencing techniques, we can determine the specific features of the
genome of any particular variety," says Mathieu Lorieux, a geneticist at
France's Development Research Institute (IRD). "Our work then consists
in cross-breeding the most useful species to obtain new ones that meet
consumer demands and environmental constraints, and are resistant to
disease."
Lorieux is
taking part in a programme to overcome the sterility barrier between
Asian (Oryza sativa) and African rice (Oryza glaberrima), the idea being
to develop hybrid varieties combining the former's productivity with
the robustness of the latter. He is also working on the plant's
architecture, so that each shoot produces more grain.
In 2011 IRRI launched a four-year programme on the Mekong delta, in Vietnam, to add flood and salt-tolerant genes to rice.
"More or less
all over the world, the potential yield from rice is about 10 tonnes a
hectare, whereas the global average is only 4.5 tonnes," Ahmadi
explains. "But the effort required to bridge this gap is increasing all
the time."
No transgenic
rice varieties are currently being cultivated, but "golden rice", a
variety developed a decade ago to have added vitamin-A, did cause
controversy. Lorieux is certain we shall one day eat transgenic rice:
"If a new disease appears and there are no resistant rice varieties, we
shall have to look for a resistant gene elsewhere or maybe make a
synthetic gene ... or give up growing rice."
This article originally appeared in Le MondeGilles van KoteGuardian Weekly
Farm & Forest Can Develop Together According To Scientists
Posted by Unknown in Agriculture and Farming, Fertility of Land, Forest, India, Research and Studies, Soil Issue, Soil Management, Sustainable Agriculture on Sunday, 27 January 2013
Agriculture
and forest can exist in harmony with each other and sustainable
development too can take place provided things are planned in that
manner.
Unfortunately,
lack of coherent and sustainable planning, a result of absence of a
'land use policy' in the country, is not allowing that to happen. As
along as human beings do not break the balance and interfere with
ecology, agriculture and forest need not be in conflict with each other.
This was the opinion of almost every speaker at the inaugural programme of a two-day brainstorming session on 'Agriculture and Forest: Conflicting Domains or Symbiotic Paradigm' organized by the National Bureau of Soil Survey and Land Use Planning (NBSS&LUP) on Tuesday.
S
M Virmani, former chief scientist of International Crop Research
Institute of Semi-Arid Tropics, Hyderabad, said that forest was capable
of giving every thing human beings could ask for including shelter,
food, and medicines but it was our greed that was leading to a situation
of conflict. Giving examples of gradual disappearance of sparrow from
urban ecology and tigers from forests, he said these were manmade
disasters. The man-animal conflict was an example of man encroaching
upon tiger's territory rather than tiger encroaching on human land. He
warned that unless we traced the causes of this conflict. the required
damage control was not possible.
A
K Joshi, principal chief conservator of forests (PCCF), Maharashtra,
spoke about the nature and conflict between people, animal, forest and
agriculture activities and also mentioned the importance of symbiosis of
these activities.
He also spoke about the livelihood opportunities through ecotourism in the tribal belts.
Ram
Prasad, ex-PCCF Madhya Pradesh, explained the role of water management
through forest for agriculture purpose and importance of forest planning
for watershed management to provide maximum benefits to farmers in the
lower reaches. Forest and agriculture both were land based, occupying a
continuum on the landscape and their co-existence was necessary for
sustainable livelihood in the tribal areas, he said.
He
also mentioned that agriculture was the main beneficiary of forest
ecosystem, conservation of forest could provide satisfaction provided
policies were formulated to address specific issues, he added.
Dipak
Sarkar, NBBS&LUP director, stressed on the role of forests in
carbon storage as trees were the biggest source of carbon sequestration.
He pointed out that cutting of forests led to huge soil erosion which
had a devastating effect on both forest ecosystem as well as human life.
Ashok
Sharma, chief general manager of Forest Development Corporation of
Maharashtra, traced the root cause of various problems to improper
policies. He categorically stated that disregarding scientific
principles of management could eventually lead to vegetation anarchy
both in forestry and agriculture. He called for a comprehensive
landscape management policy.
Arun
Chaturvedi, principal scientist and head of land use planning at
NBBS&LUP, spoke on symbiosis of agriculture and forests. He observed
that climate change would affect rainfed agriculture and increase
pressure on the forests.
He stressed on the need for creating awareness among farmers about value of non-timber forest produce.
He
said in erstwhile forested areas, it was not possible to sustain a
family of even 4-5 persons on one or two hectare of land. The income
from agriculture needed to be supplemented with additional income from
forest produce or other ancillary activities like poultry, pisciculture
small ruminant animals etc.
Expert View
*
Since forests are biggest source of carbon-dioxide sequestration,
conscious efforts should be done to increase forest cover without
displacing forest dwellers
* Efforts must be made to minimize global warming caused through agriculture
* Agriculture growth should shift from horizontal to vertical
* Identify faults in existing forest and agriculture development processes and make efforts to rectify them
* Evolve better and scientific policies of land use for sustainable forest and agriculture development
* Develop a land use policy for country
* Increase per hectare productivity of agriculture and diversify agriculture
Times of India
Choose Chicken Over Beef To Cut Stroke Risk - Study
Posted by Unknown in Beef, Chicken, Health Issues, Meat, Research and Studies
(Reuters)
- While a high-protein diet may have health benefits, not all protein
is equal -- eating lots of red meat raises the risk of having a stroke
while poultry lowers it, according to a U.S. study.
"The
main message from this paper is that the type of protein or the protein
package is really important for the risk of stroke," Frank Hu at the
Harvard School of Public Health said of the study, which was published
in the journal Stroke.
"We have to consider protein in the context of the foods."
Hu
and a team of researchers collected data from two massive health
surveys that tracked nearly 130,000 men and women from roughly middle
age to their senior and elderly years.
Over the 20-some years of the study, nearly 1,400 men and more than 2,600 women had a stroke.
To
see what influence different types of dietary protein had on the risk
of stroke, the researchers divided up the people in the study based on
how much red meat, poultry, fish, dairy and other sources of protein
they typically ate each day.
Men
who ate more than two servings of red meat each day, which was at the
high end of the meat eaters, had a 28 percent increased risk of stroke
compared to men who on average had a third of a serving of red meat each
day, the low end of the meat eaters.
Women
who ate nearly two servings of red meat a day had a 19 percent higher
risk of stroke than women who ate less than half a serving each day.
Swapping
in one serving of poultry lowered stroke risk by 27 percent, a serving
of nuts or fish was linked to a 17 percent drop, and a serving of dairy
dropped the risk by 10 to 11 percent.
A
serving of red meat was considered to be 113 to 170 grams (4 to 6 oz)
of beef, or a hamburger patty. A serving of poultry was considered to be
113 grams.
People
who ate the most chicken or turkey each day, about a half serving for
women and three-quarters of a serving for men, had a 13 percent reduced
risk of stroke compared with those who ate barely more than a serving a
day.
Researchers
did not prove that beef is to blame for the increased number of
strokes, but Adam Bernstein, lead author of the study, said it could be
that the fat and iron in red meat play a role.
An
earlier study led by Susanna Larsson at the Karolinska Institute in
Stockholm, Sweden, also found that eating red meat had a link to the
risk of stroke.
"I
do not think that poultry has been considered as a protein source that
might lower the risk of stroke. This is new," Larsson told Reuters
Health in an email.
One
surprise was that fish seemed to offer no protection against stroke,
although Bernstein said it was possible that the benefits of fish depend
on how it's served.
Red Meat vs White Meat
Posted by Unknown in Meat, Research and Studies on Sunday, 9 September 2012
Whether it's beef or chicken you're in the mood for, it's okay, as long as they are both lean meat.
The Chicago Center of Clinical Research examined the changes in blood cholesterol in nearly 200 men and women, a study funded by the National Cattlemen's Beef Association, in the Archives of Internal Medicine.
These men and women were to follow the federal governments' National Cholesterol Education Program heart-healthy diet for 36 weeks. During these nine months, the subjects were directed to consume either six ounces of beef, veal or six ounces of chicken or fish per day, for five to seven days a week.
The results showed that cholesterol levels had decreased by 1.0 percent in patients assigned to lean red meat and by 1.8 percent in those assigned to lean white meat. LDL or "bad" cholesterol reduced by 1.7 percent in patients eating primarily lean red meat and 2.9 percent in those eating primarily lean white meat. "Good" cholesterol, HDL-thought to help protect against heart disease-increased two percent in both groups.
Dailynews.yahoo.com,
June 28, 1999
