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Archive for the ‘Insects’ Category

Released: 29-Sep-2014 4:00 PM EDT
Source Newsroom: University of Wisconsin-Madison

Citations
Proceedings of the National Academy of Sciences, Sep-2014
Newswise — MADISON, Wis. — Mountain pine beetles get a bad rap, and understandably so. The grain-of-rice-sized insects are responsible for killing pine trees over tens of millions of acres in the Western U.S. and Canada over the last decade.
But contrary to popular belief, these pests may not be to blame for more severe wildfires like those that have recently swept through the region. Instead, weather and topography play a greater role in the ecological severity of fires than these bark-boring beetles.
New research led by the University of Wisconsin-Madison and the Washington State Department of Natural Resources provides some of the first rigorous field data to test whether fires that burn in areas impacted by mountain pine beetles are more ecologically severe than in those not attacked by the native bug.
In a study published this week in the Proceedings of the National Academy of Sciences, UW-Madison zoology professor Monica Turner and her graduate student, Brian Harvey, show pine beetle outbreaks contributed little to the severity of six wildfires that affected more than 75,000 acres in the Northern Rocky Mountains in 2011. They also show that the beetle outbreaks, which occurred from 2000 through 2010, have not directly impacted post-fire recovery of the forests. The study does not, however, address fire behavior, such as how quickly fires spread or how dangerous they are to fight.
While the findings may exonerate the insect scapegoats, they should also help ecosystem managers better respond to changes in the face of climate-driven disturbances, like drought and warmer temperatures.
Large, severe fires are typical in the lodgepole pine forests found throughout the region, even without mountain pine beetle outbreaks. However, as the climate has warmed, outbreaks and big fires have both become more common. The phenomenon of more beetles has meant more dead trees, and some have grown concerned about how beetle attacks and wildfires may interact.
“The conventional wisdom is that a forest of dead trees is a tinder box just waiting to burn up,” says Turner, who has long studied the forest landscape of the Mountain West. “There were very little data out there but a lot of concern.”
Forests attacked by bark beetles — which burrow into the bark of lodgepole pines to mate and incubate their larvae — can seem nothing more than ample kindling for a raging blaze, with their dead wood and dry, reddish-brown needles.
The burrows the beetles carve under the bark of pines, called galleries, choke off water and nutrient circulation in the trees. The trees die and, for the first couple of years, they hold on to their dry, lifeless needles. Scientists call this the “red stage,” and some believe these trees could fuel more severe fires.
By year three, most beetle-attacked trees have entered the “gray stage,” dropping their once green pine foliage, becoming needleless wood carcasses.
Earlier studies from Turner’s group suggested that beetle outbreaks would not lead to more severe fires. But without actual fires, the interaction could not be tested.
However, in 2011, wildfires throughout eastern Idaho and western Montana — in forests that had experienced varying mountain pine beetle outbreak impacts — provided opportunity for the research team to begin to answer the question: Do the two disturbances, beetle attacks and wildfire, together change the ecological response of the forest to fire?
Fortunately for the team, among the burned areas studied were pine stands that had not been attacked by beetles. These areas served as controls. Others suffered a range of mortality from the beetles; in some stands, beetles killed nearly 90 percent of the trees prior to wildfire. The fires that raged also ran the spectrum of severity, allowing the researchers to compare a number of variables.
Some study plots comprised mostly live trees, while others contained mostly red-stage or gray-stage trees — allowing the researchers to assess whether plots with red-stage trees (with dry needles) experienced greater levels of fire severity than plots with mostly gray-stage trees (no needles), as they and others had expected.
The study team examined ecosystem indicators of fire severity, such as how many trees were killed by fire and how much char covered the forests.
Engaging in what Harvey calls “post-fire detective work,” in 2012, the scientific team evaluated fire severity in each study plot and stripped sections of bark from over 10,000 trees to determine what killed them, beetles or fire. Beetle galleries can remain visible under the bark even after fire.
As they sifted through the blackened trees and forest floor, the team became covered with ash and soot.
“We looked like coal miners when we were done,” says Harvey.
They found that the severity of the outbreak and whether trees were in the red or gray stage had almost no effect on fire severity under moderate burning conditions.
Only under more extreme fire-burning conditions — when it was hot, dry and windy — did areas with more beetle-killed trees show signs of more ecologically severe fires, such as more deeply burned trunks and crowns (the part of the tree that includes its limbs and needles). The presence of more gray-stage trees actually had a stronger impact on fire severity than the amount of red-stage trees, to the surprise of the scientists.
Overall, however, Turner says the effects of beetle outbreaks on fire severity took a back seat to stronger drivers — primarily weather and topography. Fire severity increased under more extreme weather, regardless of pre-fire outbreaks, and forest stands higher in the landscape burned more severely than those at lower elevation as fires moved uphill, building momentum.
“No one says beetle-killed forests won’t burn,” says Turner. “The data set looks at whether they burn with different severity compared to unattacked forests burning under similar conditions.”
The team was also interested in whether beetle outbreaks slowed the recovery of the forests after fires. Lodgepole pines are adapted to fire, containing two types of seed-carrying cones: those that release seeds as soon as they mature and those that require fire to open, blanketing the forest floor with potential new life following a blaze.
By counting the number of post-fire tree seedlings in their plots, the researchers found very little beetle-related impact. Tree seedlings were most numerous where more of the fire-killed trees bore the fire-adapted, or serotinous, cones. Beetle-killed trees likely contributed to post-fire seedling establishment, too, as their seeds remain viable in cones if they are not consumed in fire. Only high-reaching char from tall flames reduced the number of seed-spreading cones.
The scientists emphasize the results may differ in other forest types or with different lengths of time between beetle outbreaks and fire.
“These are both natural disturbances, fire and beetle outbreaks,” says Turner. “It’s not surprising the ecosystem has these mechanisms to be resilient. What we as people see as catastrophes are not always catastrophes to the ecosystem.”
The study was funded by Joint Fire Science Program Grants and the National Park Service/George Melendez Wright Climate Change Fellowship.

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Shawn463

Monday, August 25, 2014/ Lincoln (NE) Journal Star

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sci dev logo

 

http://www.scidev.net/global/farming/news/benin-starts-feeling-the-cost-of-rice-pests.html

Speed read
Benin is now storing some 150,000 tonnes of rice on farms

But insect pests are taking a financial toll on the stores, destroying up to five per cent of rice

Regional variations could reveal more about the best ways to tackle the pests

BeninDD7BCB078ED1A45800578978E33866E0 image credit: Flickr/IRRI Images

[COTONOU, BENIN] Insect pests that attack stored rice are causing financial losses to farmers in Benin, researchers report in the first such study of the crop in the country. But they also found significant regional differences in damage.

According to their paper, published in the Journal of Applied Sciences earlier this year (21 February), rice production in the past was not high enough in Benin to justify long-term storage on farms so insect damage was less significant.

But since 2009, rice production has increased in many African countries and storage has become common practice. In 2012, Benin recorded 150,000 tonnes of stored paddy rice.

The researchers sampled 65 rice stores around the country and carried out a survey among farmers to determine their views on the economic importance of insect damage.

For a storage period of four to six months, they found financial losses were up to 21,315 Francs of the African Financial Community (around US$42) per tonne of stored rice in the south of the country and up to US$16 in the north.

By weight, they reported losses of about 5.5 per cent after six months of storage in the south, four per cent in the central region and 1.6 per cent in the north.

The damage caused by insect pests includes a reduction in nutritional value, grain discolouration, reduced germination, bad odour and taste, and the formation of mycotoxins that can cause serious illness in consumers, says lead author Abou Togola, an entomologist at the Africa Rice Centre (AfricaRice) in Benin.

 

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The Gympie Times

12th Aug 2014 5:17 AM

http://www.gympietimes.com.au/news/new-lures-use-pheromones-trap-and-monitor-bugs/2348506/

NEW innovative lures for trapping major horticultural pests will soon give growers an effective tool for better on-farm integrated pest management.

Department of Agriculture, Fisheries and Forestry business manager Jodie Campbell said the new traps would help growers control both banana spotting bugs and fruit spotting bugs, leading to less crop damage and improved productivity.

“Banana spotting bugs and fruit spotting bugs are two major pests of a wide range of tropical and subtropical crops including avocado, macadamia, papaya, mango, limes and custard apples,” she said.

“These pests were notoriously difficult to monitor, which is a large reason why growers in tropical and sub-tropical regions of Australia were forced to use broad-spectrum cover sprays.

“After more than 20 years of research and development, DAFF entomologists are now seeing very promising results from these new lures that use pheromones to trap and monitor the bugs.

“The pheromone lures have been effective in attracting both male and female spotting bugs and the ‘sticky panel’ trap component we designed is highly effective at catching these bugs.

“We are now at the stage of working with a commercial partner to maximise the potential of the lures to benefit the Australian horticultural industry.

“This is great news for growers, who will be able to access this technology from around mid-2015.”

Organic Crop Protectants was selected as the commercial partner to take the innovative lure technology to the market.

“OCP is a well-qualified company that has been commercially focused in the business of integrated pest and disease management for over 20 years,” Ms Campbell said.

“OCP’s plan will be to support further research and optimise the lures and traps into an integrated pest management system.

“The aim is to provide effective integrated pest management tools that give farmers better confidence to make the transition to more sustainable farming practices.”

The selection of OCP as the commercial partner for the new traps was undertaken through an open, competitive tender process by DAFF and Horticulture Australia.

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Daily Trust

http://allafrica.com/stories/201408141365.html?viewall=1

By Ojoma Akor
Cocoa is a very important cash crop in Ghana and is one of the main contributors to the country’s foreign exchange earnings. But like other crops, it is also plagued by various diseases and pests.

The Cocoa Research Institute of Ghana (CRIG) is called Tafo Cocoa Station when it was established in 1938 and later changed its name to the West African Cocoa Research Institute (WACRI) in 1944. It has mandate of conducting research to facilitate improved production of disease-free or disease-resistant cocoa, not only in the Gold Coast (now Ghana) but also in other West African countries which were under British rule, including Nigeria.

However, various countries later established their own research institutions after they gained independence and Ghana renamed WACRI as the Cocoa Research Institute of Ghana (CRIG).

The Cocoa Research Institute of Nigeria (CRIN) was established in Ibadan, Oyo State, on December 1, 1964, as a successor autonomous research organisation to the Nigerian substation of the defunct West African Cocoa Research Institute (WACRI).

According to the Executive Director of Cocoa Research Institute of Ghana (CRIG), Dr Franklin Amoah, the institute was established in 1938 after a farmer observed some unusual symptoms on his cocoa tree as a result of diseases, particularly the swollen shoot disease in 1936.

The institute was established to look into the case and other diseases and pests problems that came up. It later became a centre for research for post-graduate students from different countries.

Amoah said when it comes to research on Cocoa, Ghana and Nigeria have many things in common, adding: “The Cocoa Research Institute of Nigeria was formerly a substation of our institute until after independence when they decided to be autonomous.

“But since then we have had a lot of collaboration and share a lot of things, including research findings. Virtually every year I travel to Ukraine where I collaborate with the Cocoa Research Institute of Nigeria,” he told media fellows of the Biosciences for Farming in Africa (B4FA) when they visited the institute in Tafo, Ghana in April.

He said the diseases and pests of cocoa are major problems but the research institute has been doing its best to keep the disease and pests under control, adding that the two major diseases that affect cocoa are the swollen shoot disease and black pod disease.

“As at now, we are managing the swollen shoot disease, we have not found any major cure for it. It is a viral disease. As I speak over two million cocoa trees have been removed, eradicated, cut out and replanted while the breeders are also trying to develop materials which are very resistant or tolerant to the disease.

“We are also putting other agronomic practices to ensure that the spread of the disease is minimised. We have what we call the barrier cropping where core plot of cocoa is surrounded by two or three lines of non host plants.”

He said the swollen shoot is a major cocoa disease in Ghana, Nigeria, Cote d’Ivoire and Togo, adding that the symptoms vary with environmental conditions. The symptoms include the swelling of the root or stem, leaf discolouration and death of the trees, thus, affecting crop yields.

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http://www.vtnews.vt.edu/articles/2014/08/082214-outreach-oiredspeckledbeetle.html

BLACKSBURG, Va., Aug. 22, 2014 – An invasive weed poses a serious and frightening threat to farming families in Ethiopia, but scientists from a Virginia Tech-led program have unleashed a new weapon in the fight against hunger: a tiny, speckled beetle.

The weed, called parthenium, is so destructive that farmers in the east African nation have despairingly given it the nickname “faramsissa” in Amharic, which, translated, means “sign your land away.” Farmers have doused the weed in pesticides and ripped it out with their hands, but it has only spread further.

After a decade-long effort, scientists from the Integrated Pest Management Innovation Lab released a parthenium-eating beetle called Zygogramma bicolorata.

“Extensive research has shown us that the beetle eats and breeds only on parthenium leaves,” said Muni Muniappan, director of the Integrated Pest Management Innovation Lab, a program funded by the U.S. Agency for International Development. “It’s been tested in Australia, India, South Africa, and Mexico with similar results.”

Parthenium is native to the Americas, where a suite of natural enemies that includes the Zygogramma beetle keeps the weed in check. But in the early 1970s, parthenium entered Ethiopia in shipments of food aid from the United States. With no serious contenders, the plant flourished.

In the past three decades, parthenium has become the second most common weed in Ethiopia, suppressing the growth of all other plants and wreaking havoc in the fields and gardens of smallholder farmers.

“The plant is an aggressive invader. A single plant can produce 25,000 seeds and completes its life cycle in six to eight weeks,” said Wondi Mersie, a Virginia State University professor and principal investigator of the Virginia Tech-led project. “It displaces native species, affects human health, and negatively impacts quality of life.”

Parthenium is poisonous. People who come into contact with it can suffer from skin irritations, bronchial asthma, and fever. Animals that eat it can experience intestinal damage, and their milk and meat becomes bitter and useless.

The Innovation Lab built a quarantine facility in 2007 to ensure that the pea-sized beetle had eyes for parthenium alone. Testing under quarantine is one of the crucial steps involved in biological control, a rigorously tested method where an invasive species’ natural enemies are used to regulate it.

“Opportunities for biocontrol in Ethiopia are huge, and there would be enormous benefits,” said Arne Witt, a biologist not associated with the Virginia Tech program who works with UK-based nonprofit CABI.

After a laborious process involving many agencies and much red tape, Zygogramma bicolorata was approved for release. Researchers collaborated with farmers, local government officials, and extension agents to construct a breeding facility and increase the number of beetles.

Finally, on July 16, the Innovation Lab team joined a group of about 30 scientists and farmers in Wollenchitti, Ethiopia, to release the insects. The group moved from parthenium patch to parthenium patch, dumping beetles from containers.

Ethiopian researchers will monitor the sites and assess the impact. As a second step, scientists are poised to release a stem-boring weevil that will join Zygogramma. But even these measures will not eliminate parthenium from Ethiopian farmland.

“Biocontrol is control, not eradication,” said Witt. “But it means that a farmer sprays less pesticide. We need an integrated strategy, and biological control is the most cost-effective strategy – let’s embrace it.”

The Integrated Pest Management Innovation Lab is managed by the Office of International Research and Education at Virginia Tech.

Dedicated to its motto, Ut Prosim (That I May Serve), Virginia Tech takes a hands-on, engaging approach to education, preparing scholars to be leaders in their fields and communities. As the commonwealth’s most comprehensive university and its leading research institution, Virginia Tech offers 225 undergraduate and graduate degree programs to more than 31,000 students and manages a research portfolio of $496 million. The university fulfills its land-grant mission of transforming knowledge to practice through technological leadership and by fueling economic growth and job creation locally, regionally, and across Virginia.

Written by Kelly Izlar

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diamond back moth

Dear Colleagues,

I am happy to inform that University of Agricultural Sciences – Bangalore, India in association with AVRDC-The World Vegetable Center (Taiwan) and Cornell University (USA) will be organizing the Seventh International Workshop on Management of the Diamondback Moth and Other Crucifer Insect Pests during March 23-27, 2015 in Bangalore, India.

The website for Registration and other workshop related details is http://www.dbmworkshopindia.org/. The website will soon be updated with additional details.

I shall appreciate if you could share this information with your colleagues and the Graduate students in your organization.
Thanks for your attention, and looking forward to have your support and participation in this workshop.

With Regards,
Srini

Dr. R. Srinivasan PhD
Entomologist and Head of Entomology Group
AVRDC-The World Vegetable Center
60 Yi Ming Liao, Shanhua
Tainan 74151, Taiwan
Ph:+886 6 583 7801 Extn.426 (O); 812 (R)
Fax:+886 6 583 0009
E-mail: srini.ramasamy@worldveg.org
Website: http://www.avrdc.org

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