Feeds:
Posts
Comments

Archive for the ‘Insects’ Category

The Life Cycle of Fall Armyworm

1d ago

Fall armyworm life cycleThe Fall armyworm, Spodoptera frugiperda, is a major invasive pest in Africa. It has a voracious appetite and feeds on more than 80 plant species, including maize, rice, sorghum and sugarcane. Another feature which makes it an incredibly successful invasive species is its ability to spread and reproduce quickly. CABI have developed a poster to show the life cycle of the Fall armyworm, which includes egg, 6 growth stages of caterpillar development (instars), pupa and adult moth. Click here to view the full poster, or read about the life cycle below.

Day 1-3
100-200 eggs are generally laid on the underside of the leaves typically near the base of the plant, close to the junction of the leaf and the stem. These are covered in protective scales rubbed off from the moths abdomen after laying. When populations are high, the eggs may be laid higher up the plants or on nearby vegetation.

Day 3-6
Growth stages 1-3: After hatching, the young caterpillars feed superficially, usually on the undersides of leaves. Feeding results in semitransparent patches, or “windows”, on the leaves. Young caterpillars can spin silken threads which catch the wind and transport the caterpillars to a new plant. The leaf whorl is preferred in young plants, whereas the leaves around the cob silks are attractive in older plants. If the plant has already developed cobs then the caterpillar will eat its way through the protective leaf bracts into the side of the cob where it begins to feed on the developing kernels. Feeding is more active during the night.

Day 6-14
Growth stages 4-6: By stages 4-6, the fall armyworm will have reached the protective region of the whorl, where it does the most damage, resulting in ragged holes in the leaves. Feeding on young plants can kill the growing point, resulting in no new leaves or cobs. Often only 1 or 2 caterpillars found in each whorl, as they become cannibalistic when larger and will eat each other to reduce competition for food. Large quantities of frass (caterpillar poo) , which resembles sawdust, will be present.

Day 14-23
After approximately 14 days the fully grown caterpillar will drop to the ground. The caterpillar will then burrow 2-8 cm into the soil before pupating. The loose silk oval shape cocoon is 20-30 mm in length. If the soil is too hard then the caterpillar will cover itself in leaf debris before pupating. After approximately 8-9 days the adult moth emerges to restart the cycle.

This information has been adapted from ‘Fall Armyworm: Life cycle and damage to Maize’
To read more about what CABI is doing to help control Fall Armyworm in sub-Saharan Africa, please visit www.cabi.org/fallarmyworm

  • Share
  • 1Comment
1 comment
  1. Reblogged this on The Invasives Blog.

 

Read Full Post »

Science/AAAS

Examples of eight fruit fly brains with regions highlighted that are significantly correlated with (clockwise from top left) walking, stopping, increased jumping, increased female chasing, increased wing angle, increased wing grooming, increased wing extension, and backing up.

Kristin Branson

Artificial intelligence helps scientists map behavior in the fruit fly brain

Can you imagine watching 20,000 videos, 16 minutes apiece, of fruit flies walking, grooming, and chasing mates? Fortunately, you don’t have to, because scientists have designed a computer program that can do it faster. Aided by artificial intelligence, researchers have made 100 billion annotations of behavior from 400,000 flies to create a collection of maps linking fly mannerisms to their corresponding brain regions.

Experts say the work is a significant step toward understanding how both simple and complex behaviors can be tied to specific circuits in the brain. “The scale of the study is unprecedented,” says Thomas Serre, a computer vision expert and computational neuroscientist at Brown University. “This is going to be a huge and valuable tool for the community,” adds Bing Zhang, a fly neurobiologist at the University of Missouri in Columbia. “I am sure that follow-up studies will show this is a gold mine.”

At a mere 100,000 neurons—compared with our 86 billion—the small size of the fly brain makes it a good place to pick apart the inner workings of neurobiology. Yet scientists are still far from being able to understand a fly’s every move.

Sign up for our daily newsletter

Get more great content like this delivered right to you!

By providing your email address, you agree to send your email address to the publication. Information provided here is subject to Science’s Privacy Policy.

To conduct the new research, computer scientist Kristin Branson of the Howard Hughes Medical Institute in Ashburn, Virginia, and colleagues acquired 2204 different genetically modified fruit fly strains (Drosophila melanogaster). Each enables the researchers to control different, but sometimes overlapping, subsets of the brain by simply raising the temperature to activate the neurons.

Then it was off to the Fly Bowl, a shallowly sloped, enclosed arena with a camera positioned directly overhead. The team placed groups of 10 male and 10 female flies inside at a time and captured 30,000 frames of video per 16-minute session. A computer program then tracked the coordinates and wing movements of each fly in the dish. The team did this about eight times for each of the strains, recording more than 20,000 videos. “That would be 225 straight days of flies walking around the dish if you watched them all,” Branson says.

Next, the team picked 14 easily recognizable behaviors to study, such as walking backward, touching, or attempting to mate with other flies. This required a researcher to manually label about 9000 frames of footage for each action, which was used to train a machine-learning computer program to recognize and label these behaviors on its own. Then the scientists derived 203 statistics describing the behaviors in the collected data, such as how often the flies walked and their average speed. Thanks to the computer vision, they detected differences between the strains too subtle for the human eye to accurately describe, such as when the flies increased their walking pace by a mere 5% or less.

“When we started this study we had no idea how often we would see behavioral differences,” between the different fly strains, Branson says. Yet it turns out that almost every strain—98% in all—had a significant difference in at least one of the behavior statistics measured. And there were plenty of oddballs: Some superjumpy flies hopped 100 times more often than normal; some males chased other flies 20 times more often than others; and some flies practically never stopped moving, whereas a few couch potatoes barely budged.

Then came the mapping. The scientists divided the fly brain into a novel set of 7065 tiny regions and linked them to the behaviors they had observed. The end product, called the Browsable Atlas of Behavior-Anatomy Maps, shows that some common behaviors, such as walking, are broadly correlated with neural circuits all over the brain, the team reports today in Cell. On the other hand, behaviors that are observed much less frequently, such as female flies chasing males, can be pinpointed to tiny regions of the brain, although this study didn’t prove that any of these regions were absolutely necessary for those behaviors. “We also learned that you can upload an unlimited number of videos on YouTube,” Branson says, noting that clips of all 20,000 videos are available online.

Branson hopes the resource will serve as a launching pad for other neurobiologists seeking to manipulate part of the brain or study a specific behavior. For instance, not much is known about female aggression in fruit flies, and the new maps gives leads for which brain regions might be driving these actions.

Because the genetically modified strains are specific to flies, Serre doesn’t think the results will be immediately applicable to other species, such as mice, but he still views this as a watershed moment for getting researchers excited about using computer vision in neuroscience. “I am usually more tempered in my public comments, but here I was very impressed,” he says.

Read Full Post »

Virginia Tech scientists rally international coalition to stop a pestilent ‘army’

July 13, 2017

A man’s hand holding two larvae next to a damaged corn plant.

A man's hand holding two worms next to a damaged corn plant.
A severely damaged corn plant shown next to two of the fall armyworms responsible for the damage. The pest usually feeds on leaves but during heavy infestations will also eat other parts of the plant, including kernels.

The fall armyworm – devastating to corn in Ethiopia, Tanzania, Kenya, and elsewhere – is subject of an emergency workshop July 14 through 16 in Addis Ababa, Ethiopia, to slow the pest’s advance in Africa and prevent its penetration into Southern Europe and Asia.

A pest native to both North and South America, the fall armyworm first landed in western Africa and reached eastern Africa a year later. The pest has the potential to destroy more than $3 billion in corn throughout Africa and trigger food shortages next year, scientists say.

Virginia Tech’s Muni Muniappan witnessed damage in April in Ethiopia, where he met with struggling farmers.

“The worm is voracious, and it must be controlled soon before the damage spreads,” said Muniappan, an entomologist and director of the Virginia Tech-led Feed the Future Innovation Lab for Integrated Pest Management.

A team of researchers from the lab is partnering with the International Center for Insect Physiology and Ecology in Nairobi, Kenya, to produce the workshop, which gathers stakeholders and experts from five countries (the United States, Ethiopia, Kenya, Niger, and Tanzania) to respond to the threat to the region’s food security.

The United States Agency for International Development, which funds the lab at Virginia Tech, is also sponsoring the workshop, where experts will share techniques with farmers to deploy against the pest.

On the continent less than two years, the fall armyworm has created a path of devastation. Its quick spread and heavy destruction make it difficult to control, leaving farmers few options but to handpick caterpillars off their plants.

The pest’s targets include 80 different plant species, some of which are valuable food crops. Many countries in East Africa experienced a sharp drought last year, which resulted in a humanitarian crisis from which millions of farmers in the region are only now recovering, according to the International Association for the Plant Protection Sciences.

The Integrated Pest Management Innovation Lab team is coordinating research in East Africa seeking ways small-scale farmers can mitigate the pest’s impact. The lab is working to identify biological agents – such as a natural enemy like a wasp – to control the fall armyworm by destroying the pest’s larvae.

Scientists are studying traps made from burlap “gunny sacks” that employ such natural enemies. Other methods under study include establishing plants near rows of crops that can keep the pest contained.

The workshop should allow the Integrated Pest Management Innovation Lab to fine-tune its research objectives, Muniappan said. He also hopes the pest, which can fly hundreds of miles once it transforms to become a moth, can be contained before it becomes widespread.

The Integrated Pest Management Innovation Lab is a project of the Office of International Research, Education, and Development, part of Outreach and International Affairs.

Written by Dana Cruikshank and Stephanie Parker

Read Full Post »

Delta farm press

Boll weevil photo
Mississippi farmers, and others throughout most of the nation’s cotton-producing regions, have saved many millions of dollars by no longer having to battle the boll weevils that had destroyed cotton yields for decades

For nearly a decade, not a single boll weevil in Mississippi

Mississippi is now entering its tenth year free of the boll weevil that cost U.S. producers billions of dollars over the past century.

Hembree Brandon | Jul 11, 2017

As he had done for the past nine years, Farrell Boyd was beaming at the joint annual meeting of the Mississippi Boll Weevil Management Corporation and the Mississippi Farm Bureau Federation Cotton Policy Committee.

“It’s a pleasure for me to echo what I’ve said for the last nine years: Mississippi continues to be boll weevil-free,” said Boyd, who is program manager for the organization. “We’re going into our 10th year and not the first weevil has been caught — which is great! And we’ve gone from over 500 employees during the height of the eradication effort to just five today.”

Royal-Langley

Robert Royal, left, Midnight, Miss., producer/ginner, and James Langley, V&M Cotton Brokers, Yazoo City, Miss., were among those attending the joint annual meeting of the Mississippi Boll Weevil Management Corporation and the Mississippi Farm Bureau Federation Cotton Policy Committee.

Mississippi producers, and others throughout most of the nation’s cotton-producing regions, have saved many millions of dollars by nolonger having to battle the pest that had destroyed cotton yields for decades, he says.

Still, “We’re not letting our guard down — we’re continuing to operate the Mississippi program in a surveillance mode. We have pheromone traps within a mile of every cotton field in the state, and we monitor them throughout the season in case any weevils should slip in on farm equipment coming from the south Texas areas where the eradication effort is still under way.”
SOUTH TEXAS AND MEXICO AREAS REMAIN

Nearly all of the U.S. cotton belt is now weevil-free, Boyd notes. “The only place where weevils still exist is in the Rio Grande Valley bordering Mexico, along the Rio Grande River, and south of Uvalde in the Winter Garden area, which is a reinfestation area. The reinfestation there emphsizes why we have to be so careful — it’s not impossible weevils could reoccur here as a result of being transported in from an infested area. It’s very important that we continue our surveillance program.”

The cooperative program between Mexico, the Texas Boll Weevil Foundation, and APHIS, to provide training and equipment for Mexico has been “very effective” in enhancing the eradication effort in that region, he says. “Unfortunately, they continue to have intermittent problems with drug cartels. A recent report noted that Mexican eradication workers were out of the field several times due to gun battles in the area. That kind of environment makes their eradication effort even more challenging.”Deere picker

deere  picker

Nearly all of the U.S. cotton belt is now boll weevil-free. Only areas in southernmost Texas and across the Rio Grande River in Mexico remain to be eradicated.

But, Boyd says, there has been “significant progress” on both sides of the border. “Through June 12, in the Rio Grande Valley of Texas, they had an 81.4 percent decrease in weevil captures compared to a year ago. In the Mexican program across the river, through June 12 they’d captured 539 weevils, a 91 percent decrease over 2016.”

Both areas have significant increases in cotton acreages this year, he says, which could have an impact on weevil numbers, “but we’re still comfortable that they’re going to achieve eradication. The cooperative effort with Mexico has been a major achievement.”

BUFFER ZONE TO PREVENT REINFESTATION

Starting in 2014, he notes, the National Cotton Council Boll Weevil Action Committee established a buffer zone in the lower Rio Grande Valley to hopefully protect the rest of the cotton belt from weevil intrusion.

“An assessment was levied to fund the buffer zone, and in 2014 each state contributed 50 cents per acre, with 25 cents per acre in years since then. The buffer program will be reevaluated at the end of five years. So far, none of the money collected has been spent because the buffer zone is in the area where the Texas boll weevil eradication is going on, so it hasn’t cost any additional money to maintain the buffer. By the end of this year the fund will have accumulated between $11 million and $12 million, which is about enough to operate the program. So, they’re holding the money in escrow in the event some of it is needed for that.”

Everything is still “looking very promising” for eradication in the lower Rio Grande Valley, Boyd says, “and we’re looking forward to another weevil-free season in Mississippi. We appreciate everyone’s assistance in watching for harvest equipment or other equipment coming into our state from south Texas so we can be sure no weevils sneak in.

Coley Bailey, Jr., Grenada, Miss., producer, and president of the Mississippi Boll Weevil Management Corporation, echoed Boyd’s enthusiasm for the ongoing success of the program: “It’s great to be almost 10 years weevil-free. When I attended my first board meeting we were $60 million in debt; today we’re blessed to be in strong financial condition. But reinfestation could be costly — and we want to do all we can to prevent that from happening.”

Read Full Post »

SE farm press

Sugar Cane Aphids South Carolina Clemson University
Sugarcane aphids colonize a grain sorghum leaf in a South Carolina field.

Sugarcane aphids return to South Carolina

Tiny, hungry and rapidly reproducing sugarcane aphids have made their annual migration to South Carolina to feast on grain sorghum, an agricultural commodity that had been gaining popularity.

Scott Miller Clemson University | Jul 09, 2017

 Tiny, hungry and rapidly reproducing sugarcane aphids have made their annual migration to South Carolina to feast on grain sorghum, an agricultural commodity that had been gaining popularity.

The bugs can’t survive South Carolina winters so they migrate from warmer states each year. Once here, they can quickly colonize plants by the thousands. In addition to injuring or even killing grain sorghum plants, sugarcane aphids secrete a sticky substance that can clog and damage agricultural harvesting equipment. Field trials in other states have shown sugarcane aphids to cause 20-50 percent crop loss in some fields and total loss in others, including in South Carolina.

 Growers should scout fields for aphids once or twice weekly and, in most cases, if more than 50 aphids are found on one leaf, growers should apply an insecticide, said Francis Reay-Jones, an entomologist at Clemson’s Pee Dee Research and Education Center near Florence. Farmers can apply either Transform WG or Sivanto Prime. Refer to the product labels for application instructions. More detailed information on insect control for grain sorghum is available online here.Grain sorghum had become an increasingly popular agricultural commodity before sugarcane aphids first arrived in South Carolina in 2014, said David Gunter, a grain specialist with Clemson University Cooperative Extension. The grain is used for animal feed. It had become a good alternative to dryland corn because of its drought resistance and strong yield potential without the need for costly insecticide treatments.

South Carolina farmers harvested around 14,000 acres of grain sorghum in 2012, more than double the amount harvested five years prior, according to the U.S. Department of Agriculture. Information is not available for more recent years, but Gunter said planted acreage has dropped.

“I think sugarcane aphids have kind of scared off growers, along with commodity prices,” Gunter said.

Data are limited on sugarcane aphid control for grain sorghum because this is a relatively new problem. Sugarcane aphids were first identified in the U.S. in Florida in 1977, but they fed on sugarcane. In 2013, the pest began feeding on grain sorghum, as well, and spread rapidly across the Southeast.

The pest has been spotted as far north as Darlington County, Reay-Jones said.

Some sorghum varieties have shown tolerance to sugarcane aphids. Gunter recommends farmers interested in grain sorghum plant DeKalb DKS 48-07 or 37-07, Pioneer 83p17 or Sorghum Partners SP7715 or SP73B12.

“When I say these varieties are tolerant, that does not mean they are resistant, but it may save farmers one insecticide application,” Gunter said.

Reay-Jones continues to test varieties for tolerance to sugarcane aphids at the Pee Dee Research and Education Center. Fellow Clemson entomologist Jeremy Greene at the university’s Edisto Research and Education Center near Blackville is performing similar testing.

“Tolerant varieties are not a silver bullet. If you get heavy pressure, you’ll still need to apply treatment,” Reay-Jones said.

Reay-Jones also is evaluating the effectiveness of insecticidal seed treatments, developing sampling plans and researching the impact nitrogen fertilization may have on the presence of sugarcane aphids.

 

Read Full Post »

EPPO Reporting Service 2017 no. 6- Diseases

2017/117 First report of ‘Candidatus Liberibacter asiaticus’ in Panama

In February 2016, ‘Candidatus Liberibacter asiaticus’ (associated with huanglongbing – EPPO A1 List) was detected for the first time in Panama. The disease was found on citrus the areas of Guabito and Las Tablas (district of Changuinoa, province of Bocas del Toro). The Ministry of Agriculture has declared a state of phytosanitary emergency and a national contingency plan has been elaborated to contain the disease and its vector, Diaphorina citri (Hemiptera: Liviidae – EPPO A1 List). In July 2016, 101 citrus plants at the sites where the disease was found were destroyed (burnt). In addition to plant destruction and surveys, the development of a national certification scheme for the production of healthy planting material of citrus has been undertaken. The situation of ‘Candidatus Liberibacter asiaticus’ in Panama can be described as follows: Present, only in some areas (province of Bocas del Toro), under official control.

Source: INTERNET Gobierno de la República de Panamá – Noticias (2017-06-05) Más de B/. 1 millón invertirán Panamá y Taiwán en proyecto para control de la enfermedad de los cítricos HLB. http://mida.gob.pa/noticias_id_4875.html – Noticias (2017-06-02) Sector public y privado analizan normativa de viveros cítricos. http://mida.gob.pa/noticias_id_4495.html – Noticias (2016-08-16) MIDA y Embajada de China (Taiwan) coordinan proyectos técnicos. http://www.mida.gob.pa/noticias_id_3977.html – Noticias (2016-07-25) Decomisan plantones de cítricos en puesto de control de cuarentena en Hornitos. http://mida.gob.pa/noticias_id_3898.html – Noticias (2016-06-01) MIDA impulsa plan de emergencia para control de enfermedad en los cítricos. http://www.mida.gob.pa/noticias_id_3739.html República de Panamá. Ministerio de Desarrollo Agropecuario. Resolucion no. OAL039-ADM-2016 of 2016-02-03. Gaceta Oficial Digital, jueves 17 de marzo de 2016 no. 27991. http://extwprlegs1.fao.org/docs/pdf/pan163996.pdf

Pictures: ‘Candidatus Liberibacter asiaticus’. https://gd.eppo.int/taxon/LIBEAS
Additional key words: new record Computer codes: LIBEAS, DIAACI, PA

Read Full Post »

fall-armyworm-frontal-MER-563x744FAW on corn leavesfall-armyworm-frontal-MER-563x744

Maize damaged by the fall armyworm, Spodoptera frujiperda

Photos courtesy of Marlin E. Rice

 

Fall Armyworm Workshop for East Africa

Harmony Hotel, Addis Ababa, Ethiopia, July 14-15, 2017

 Background

The Fall Armyworm (FAW), Spodoptera frugiperda, a native to the tropics and sub tropics of North and South America, is a polyphagous pest attacking more than 80 different plant species, including maize. Maize is a major food staple in sub-Saharan Africa upon which more than 300 million people depend. Depending on the degree of infestation, the FAW can cause huge losses in maize yields and in some cases, total crop loss.

This pest has recently invaded Africa and is ravaging crops in more than 20 countries. It was first reported in Nigeria, West Africa, in early 2016. It soon spread to southern Africa in late 2016 and by early 2017 was confirmed to be in East Africa. If it is not effectively controlled, it is expected to cause $3bn loss to maize in Africa along with serious food shortages expected in the next year.

Needed action

Rapid action, immense awareness creation, and technological innovation, along with national, regional and international collaboration are required to thwart the threat of the fall armyworm in order to avoid severe economic losses among smallholder farmers across Africa. Crucial concerted efforts from international research centers, national research and extension programs, international development organizations, policy makers, and donor communities in East Africa are required to develop and deploy an effective integrated pest management strategy, which can provide sustainable solutions to effectively tackle the adverse effects of the FAW. Millions of East African farmers are currently on the road to recovery from last year’s shocking drought that resulted in a humanitarian crisis. Now, they are facing this new threat to their livelihood.

Workshop objectives

To effectively fight this pest, the IPM Innovation Lab/ Virginia Tech and USAID, in partnership with icipe, is organizing a regional FAW awareness and management workshop. This workshop will bring stakeholders and experts from the United States, Ethiopia, Kenya, Niger, and Tanzania to share their experiences and challenges in dealing with the FAW. The workshop will also include discussions on needed action in terms of research and development in the region. The results and recommendations made from this workshop will be used as feedback to design an effective management strategy to manage the FAW in East Africa and beyond.

On behalf of the workshop organizers

Tadele Tefera

Country Head icipe Ethiopia, PI for IPM Innovation Lab Grains IPM for East Africa Project and IAPPS Coordinator, Region V East Africa

 

Read Full Post »

Older Posts »