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2017/065 First reports of a new bacterial leaf blight of rice caused by Pantoea anana and Pantoea stewartii in Benin and Togo

In Benin, surveys were carried out from 2011 to 2015 in rice fields to assess the importance of bacterial leaf blight caused by Xanthomonas oryzae pv. oryzae (EPPO A1 List). Symptomatic leaf samples were collected and tested. As all isolates gave negative results in a multiplex PCR test for X. oryzae, further studies were conducted and revealed the presence of bacteria belonging to the genus Pantoea. Molecular and pathogenicity tests (to fulfill Koch’s postulates) confirmed that the bacteria which had been isolated from rice leaves were P. ananatis and P. stewartii (EPPO A2 List). It is noted that symptoms were  observed in all surveyed localities (14 sites) with a disease incidence varying from 30 to 100%. In Togo, surveys were also carried out in 2013 and 2014 in the main rice-growing regions (Kovié and Kpalimé) to evaluate the prevalence of plant-pathogenic bacteria. Rice leaves showing characteristic symptoms of bacterial leaf blight were collected and tested. Similarly, the bacteria which were isolated from rice leaves and grains were shown to be P. ananatis and P. stewartii. According to the authors, this is the first time that P. ananatis and P. stewartii species are found causing a leaf blight disease on rice crops in Benin and Togo. According to the EPPO Secretariat this is also the first time that P. stewartii is reported from Africa.

Source: Kini K, Agnimonhan R, Afolabi O, Milan B, Soglonou B, Gbogbo V, Koebnik R, Silué D (2017) First report of a new bacterial leaf blight of rice caused by Pantoea ananatis and Pantoea stewartii in Benin. Plant Disease 101(1), p 242. Kini K, Agnimonhan R, Afolabi O, Soglonou B, Silué D, Koebnik R (2017) First report of a new bacterial leaf blight of rice caused by Pantoea ananatis and Pantoea stewartii in Togo. Plant Disease 101(1), 241-242.

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From Pestnet

USDA releases proposals to fight citrus greening & diamondback moths

In the past two weeks, USDA’s Animal and Plant Health Inspection Service (APHIS) has released documents on proposals to release two genetically modified (GM) organisms: diamondback moths and a virus designed to control the citrus greening disease attacking the citrus industry.

DB moth

Diamondback moths are a global pest of cruciferous crops such as broccoli, Brussel sprouts and cabbage. On April 18, the USDA released a draft environmental assessment of a proposed experiment by a Cornell entomologist with GM diamondback moths.

The scientist, Anthony Shelton, plans to release tens of thousands of GM moths into a 10-acre vegetable field to test their potential as an “insecticide-free” control option for diamondback moths. The GM moths have been engineered to repress female survival, known as a “female autocidal trait.”

You can read the full assessment which concludes it will have no harmful effects here.

Citrus Greening
A Florida nursery, Southern Gardens Citrus Nursery, is proposing the release of a GM virus, Citrus tristeza virus, which has been engineered to express bacteria-fighting proteins found in spinach. The GM virus, which has been undergoing controlled field tests since 2010, would be grafted — not sprayed — onto citrus trees in Florida. USDA has announced its intent to launch an environmental impact statement on Southern Garden’s proposal.

source: dtnpf.com

Publication date: 4/25/2017

Diamondback moths are a global pest of cruciferous crops such as broccoli, Brussel sprouts and cabbage. On April 18, the USDA released a draft environmental assessment of a proposed experiment by a Cornell entomologist with GM diamondback moths.

The scientist, Anthony Shelton, plans to release tens of thousands of GM moths into a 10-acre vegetable field to test their potential as an “insecticide-free” control option for diamondback moths. The GM moths have been engineered to repress female survival, known as a “female autocidal trait.”

You can read the full assessment which concludes it will have no harmful effects here.

Citrus Greening
A Florida nursery, Southern Gardens Citrus Nursery, is proposing the release of a GM virus, Citrus tristeza virus, which has been engineered to express bacteria-fighting proteins found in spinach. The GM virus, which has been undergoing controlled field tests since 2010, would be grafted — not sprayed — onto citrus trees in Florida. USDA has announced its intent to launch an environmental impact statement on Southern Garden’s proposal.

source: dtnpf.com

Publication date: 4/25/2017

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From Pestnet

reliefweb
http://reliefweb.int/report/kenya/fall-armyworm-spreads-east-africa

Report

from Food and Agriculture Organization of the United Nations

Published on 25 Apr 2017 — View Original

25/04/2017

As millions of east African farmers seek to recover from a devastating drought, they face a new threat – the fall armyworm. The pest has been recently detected in Kenya and is suspected to have entered the country from Uganda. It is also known to be present in Burundi, Ethiopia and Rwanda.

The fall armyworm was first reported in western Kenya by farmers in March 2017, and immediately confirmed by the Kenya Plant Health Inspectorate Service and Kenya Agricultural and Livestock Research Organisation. The initial counties infested were Busia, TransNzoia, Bungoma, Uasin Gishu and Nandi.

However, the pest has rapidly spread to key maize- and wheat-producing counties, including Kericho, Bomet and Narok in South Rift, as well as Nakuru and Baringo in Central Rift. Further, there are unconfirmed reports of presence of the pest in eastern and coastal areas. The major crop currently being ravaged by the pest is maize, which is at various stages of growth, ranging from germination to shoulder-high (nearing tasselling).

In Kenya, the Government has sought to respond quickly and effectively to prevent an outbreak from dampening prospects for the recently started main cereal-cropping season. With extension service providers and farmers not having much or any knowledge or skills on how to control and manage the fall armyworm, the Government has formed a platform to coordinate development of intervention strategies. However, as yet there are no funds available for implementation. Early this year, the Ministry of Agriculture and Natural Resources of Ethiopia received a report from Mizan Plant Health Clinic, which had intercepted the fall armyworm in five woredas (districs) of three zones – Bench-Maji, Kaffa and Sheka – located in southwestern Ethiopia, where early maize planting begins during January, February and March.

The Horn of Africa is already facing a regional humanitarian crisis, triggered by drought and leading to skyrocketing food insecurity, particularly among livestock-owning communities, with lives and livelihoods devastated across the region. Today, almost 18 million people in the Horn of Africa are severely food insecure as consecutive seasons of poor rainfall have led to crop failures, widespread pasture and water shortages, reduced opportunities for rural employment, increasing livestock deaths, rising food prices and rapidly diminishing access to food for poor households.

Drought has hit hardest in rural areas, where food security, nutrition and income generation is largely dependent on local agricultural and livestock production. In Somalia, Kenya, Ethiopia, Djibouti, South Sudan and Uganda, drought has scorched crops and rangelands, dried water sources and led to increasing rates of starvation, disease and death among livestock. Families are employing extreme coping strategies to survive, including skipping meals, selling productive assets and the migration or displacement of entire households.

The ongoing planting season represents one of the main opportunities to tackle hunger and protect lives and livelihoods in the region. However, with fall armyworm having a preference for maize and other cereals, an outbreak threatens to further undermine the food security of families that can ill afford another crisis. The pest is known to cause 100 percent crop losses.

There is urgent need therefore to support the county and national governments to halt further spread and damage. Failure to control the pest would result in serious food, economic and social insecurity in Kenya, and indeed in Eastern and Central Africa.

On 25 April 2017, FAO convened a technical meeting in Nairobi, Kenya to deliberate on the fall armyworm response with the Governments and partners in Southern Africa. The outcomes of this meeting were then deliberated at an Africa-wide meeting organized by FAO, the Alliance for a Green Revolution and the International Maize and Wheat Improvement Centre in Nairobi on 27 and 28 April. The meeting reviewed the status of fall armyworm incidence and impact in Africa, discussed the available technological options for minimizing the damage caused by the pest and provide concrete recommendations on the strategy for effective management of fall armyworm in Africa. The meeting will also identify appropriate partnerships to develop and deploy short, medium and long-term solutions to the farming communities in Africa.

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fresh plaza logo

Kiwi bacteriosis control now a reality

The international Journal of Plant Disease and Protection finally published the research financed by MIPAAF and coordinated by Prof. Giorgio M. Balestra which saw the cooperation between the Department of Agricultural Sciences (DAFNE) of Università della Tuscia and the Department of Life Sciences and Biotechnology (SVeB) of the University of Ferrara

Title: “Microparticles containing gallic and ellagic acids for the biological control of bacterial diseases of kiwifruit plants

Authors: Antonio Rossetti, Angelo Mazzaglia, Massimo Muganu, Marco Paolocci, Maddalena Sguizzato, Elisabetta Esposito, Rita Cortesi, Giorgio Mariano Balestra.

It is a lengthy study that demonstrates how it is possible to use vegetable substances to monitor the different phytopathogenic bacteria that cause much worry in all the areas growing Actinidia spp..

The cultivation of actinidia to produce kiwis has become increasingly important in Italy as well as in various areas around the world. At the same time, however, bacterial diseases are affecting its cultivation. The most dangerous is without doubt the bacterial canker caused by Pseudomonas syringae pv. actinidiae (Pss) Takikawa et al., also known as Psa, which damages all vegetative organs.

Serious damage is caused also by the drop in temperatures in spring, as is the case this year, associated with other two bacteria – Pseudomonas syringae pv. syringae (Pv) van Hall, responsible for floral bud necrosis and Pseudomonas viridiflava (Burkholder) Dowson, the bacterial blight which affects leaves and floral organs.

In Italy, prevention is carried out by using copper salts as well as a biological control agent (B. a. subsp. plantarum ceppo D747) during blossoming. Other areas outside the EU employ antibiotics with serious repercussions on the environment and leading to the development of antibiotic-resistant bacteria strains.

This study assessed the effectiveness of gallic and ellagic acids, i.e. natural substances that are easily attainable from many vegetable tissues and with high anti-microbial properties.

These natural, active principles proved effective as pure substances both in the lab and in vivo (greenhouses, then open-field actinidia orchards naturally affected by Pss, Pv and Psa).The vegetable active principles significantly reduced the various bacterial populations as well as the damage caused both through artificial contamination and by using them on orchards naturally affected by Pss, Pv and Psa.

In association with the intrinsic activities, the active principles proved particularly effective when employed through micro-formulations in micro-capsules, thus preventing alterations (physical-chemical) and enabling a controlled release of the principles over two weeks protecting all vegetable organs.

In addition, the activity of these formulations on both plant development and final production was also assessed. All parameters showed how these micro-formulations do not affect plant development (the plants treated with micro-capsules had a higher chlorophyll content in the leaves and the fruits, though with the same size and Brix level, were more compact).

The results obtained with this study represent a significant contribution towards the attainment of formulations that can successfully counter dangerous micro-organisms like those affecting actinidia with a sustainable/organic approach.

Reducing the use of copper salts to protect crops is a process dictated by the EU. As of January 2018, further reductions of Cu++ will be introduced, thus valid alternatives must be found.

This study suggests how gallic and ellagic acids, when formulated together in microformulations, can be successfully employed in sustainable/organic defence strategies against pathologies like those currently affecting actinidia.

The active principles and technology used in this research constitute an important base, as what described can be applied to different pathogens/ crops, thus reducing the use of chemicals and therefore chemical residue.

Additional studies are currently being carried out concerning organic nano-formulations for the protection of different crops both in the fields and during the storage and commercialisation stages. They aim at a further reduction of the (natural) active principles used, at a prolonged controlled release and at making it so that formulations can penetrate fruit/plants and target the pathogen.

For further information:
Prof. Giorgio M. Balestra
DAFNE (Department for Agriculture, Forestry, Nature and Energy)
University of Tuscia
Via S. Camillo de Lellis
01100 Viterbo
Tel.: (+39) 0761 357474
Cell.: (+39) 333 4246404
Fax: (+39) 0761 357473
Email: balestra@unitus.it
Web: www.unitus.it
Skype: giorba5618
Personal page: www.dafne.unitus.it/web/interna.asp?idPag=1118

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terradaily-454

Scientists suggest the world should brace itself for a new wave of biological invasions

FLORA AND FAUNA

Scientists suggest the world should brace itself for a new wave of biological invasions
by Staff Writers
Cambridge UK (SPX) May 04, 2017

A global invasion.

We are all becoming increasingly familiar with the impacts of invasive species. Knotweed from Japan can destroy building foundations, zebra mussels from eastern Europe can clog-up drinking water pipes, and an Asian fungus is causing ash tree die-back in our forests. Now an international team of scientists has identified how our rapidly changing world will bring new types of invaders, often from very unexpected places.

non-native-plantings-have-impact-on-diversity-insect-populations-lg

Invasive non-native species are among the greatest drivers of biodiversity loss on the planet and cost the British economy Pounds 1.7bn each year. “Our study found that environmental change, new biotechnology and even political instability are all likely to result in new invasions that we should all be worried about” said Dr. David Aldridge of Cambridge University, who hosted the meeting of 17 scientists from across four continents.

Globalization of the Arctic, emergence of invasive microbial pathogens, advances in genomic modification technology, and changing agricultural practices were judged to be among the 14 most significant issues potentially affecting how invasive species are studied and managed over the next two decades. “We have identified some potential game-changers” said Prof. Anthony Ricciardi from McGill University, who led the study.

Globalization of the Arctic
Until now, the Arctic has been among the least accessible regions on the planet, escaping extensive alien species invasions like those that have affected temperate and tropical areas of the world. However, the rapid loss of sea ice is opening the region to shipping, oil and mineral extraction, fishing, tourism, and shoreline development – all of which facilitate introductions of alien species.

The loss of sea ice is also creating a major new corridor for international shipping between the Pacific and Atlantic Oceans, which will affect invasion risks throughout the Northern Hemisphere. “The gold rush has begun for major expansion of human activities in the Arctic, with the potential for large-scale alien species transfers” says Dr. Greg Ruiz (Smithsonian Environmental Research Center).

Emergence and spread of invasive microbial pathogens
Disease-causing bacteria, water molds, fungi and viruses are being given increasing opportunities to spread into regions where they never previously existed and where they may attack new hosts. They can also undergo rapid genetic changes that cause previously innocuous forms to become virulent.

Invasive microbes have devastated populations of animal and plants that have had no evolutionary exposure and thus no immunity to them.

Recent examples include: the chytrid fungus “Bsal” that is killing salamanders in Europe; the white-nose fungus that is destroying bat colonies in North America; and sea star wasting disease along the Pacific coast of North America, considered to be among the worst wildlife die-offs ever recorded. The proliferation of microbial pathogens is a burgeoning threat to biodiversity, agriculture, forestry and fisheries.

Biotechnological advances and applications
Advances in genomic modification tools hold both promise and challenges for managing invasive species. Very recently, genetically modified versions of an invasive mosquito were released in the Florida Keys in a controversial attempt to interfere with the mosquito’s reproductive life cycle, thereby preventing it from vectoring the spread of invasive Zika, Dengue and Chikungunya viruses to humans.

“The push to use genetically modified agents to control invasive species will continue to grow”, says Prof. Hugh MacIsaac (University of Windsor), “and with it will come public opposition and the view that we are opening Pandora’s Box”.

Changing agricultural practices
The team also identified changing agricultural practices as a potential source of invasion threats. Virtually unregulated new agricultural crops and practices open the door to potentially disastrous unintended consequences. An Asian cricket species reared for “cricket flour” – all the rage in the USA – has already established in the wild. Worse, as a disease ravages this species, farmers have imported other kinds of crickets that might well invade in nature.

But possibly the biggest threat of all is the growing use by agribusiness of soil bacteria and fungi to increase crop production. “The cultivation and distribution of ‘growth enhancing’ microbes could cause some crop plants or plant species residing near agricultural fields to become invasive pests” says Prof. Daniel Simberloff (University of Tennessee).

Invasive species denialism
An additional challenge is public perception of invasion science. Scientific evidence on invasive species impacts is under attack, with much of the opposition value-based rather than science-based. This form of science denialism involves a rejection of peer-reviewed evidence along with an attempt to re-frame, downplay or even deny the role of invasive alien species in global environmental change.

“Denialism in science is not new, but its growth in the context of invasive species is especially worrying for people trying to conserve unique native biodiversity” says Prof. Tim Blackburn (University College London). “Manufacturing doubt about the negative impacts of invasive species can delay mitigating action to the point where it is too late.”

Research paper

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Cucumber green mottle mosaic virus could have entered Queensland through imported seeds – ABC News (Australian Broadcasting Corporation)

//4654321.fls.doubleclick.net/activityi;src=4654321;type=abcne0;cat=abcne000;ord=4463444923102;~oref=http%3A%2F%2Fwww.abc.net.au%2Fnews%2F2017-05-04%2Fcucumber-green-mottle-mosaic-virus-imported-seed-biosecurity-qld%2F8494354?

Ccucumber green mottle virus could have entered Queensland through imported seeds

 

Posted 3 May 2017, 3:18pmWed 3 May 2017, 3:18pm

Biosecurity authorities are trying to figure out how a fruit and vegetable rotting disease broke out in Queensland, but have initial suspicions it was through imported seed.

Farmers from the Bundaberg region are angry cucumber green mottle mosaic virus (CGMMV) has recently been discovered on five local properties, owned by two growers.

CGMMV causes internal rot and discolouration in some cucurbit family fruit and vegetables, and its discovery comes months after an outbreak of white spot disease decimated the aquaculture industry in south-east Queensland.

Biosecurity Queensland spokesman Mike Ashton said the virus was not harmful to humans, but could ravage parts of the agriculture industry if a widespread outbreak occurs.

He said there was a possibility the virus was brought onto the infected farms by imported seeds.

That is considering the businesses operate independently and do not share personnel and equipment.

“That kind of increases the risk that perhaps it was seed that was the source of the introduction,” he said.

“It’s highly unlikely that we’ll ever be able to pinpoint exactly how it got introduced.”

“We’re certainly doing tracing investigations to try and identify the source.”

Farmers like Gino Marcon are angry there has been an outbreak of another virus, and are switching to less risky crops.

Mr Marcon normally grows a wide range of vegetables on his farm, but this year, he is only growing tomatoes to avoid CGMMV.

“We’ve actually stopped growing cucumbers, we’ve sort of got a wait-and-see attitude at the moment,” Mr Marcon said.

“We’re a bit worried that the disease may affect our zucchini production, so we’ve switched over to 100 per cent tomato production in our greenhouses.”

He blamed biosecurity authorities for the outbreak.

“We’ve lost confidence in the system and that’s the biosecurity system,” Mr Marcon said.

“We think it’s not broken, it’s shredded to bits. It’s simply not working.

“I think the whole system needs to be overhauled, we’re not getting value for money for the money being allocated to biosecurity.

“[Politicians] need to look long and hard at the whole system and change it.”

Mr Ashton rejects the allegation that the system has failed.

“We have managed to restrict the disease to a very small number of properties in Queensland,” he said.

“Unlike the Northern Territory and increasingly so in Western Australia where the disease has become quite established.”

There have been previous outbreaks of CGMMV in the Territory and WA, and an isolated case at Charters Towers in North Queensland in 2015.

Biosecurity Queensland hope the Charters Towers farm will be declared clear of the virus later this year.

The Federal Agriculture Department introduced mandatory imported seed testing to try and combat CGMMV in 2014.

In a statement, the department said it uses a sample size more than four times the size (9,400 seeds) than that used internationally (2,000).

It said that gave a high level of confidence in the results.

Topics: pest-management, rural, quarantine, crop-harvesting, agricultural-policy, vegetables, activism-and-lobbying, agricultural-crops, fruit, fruits, bundaberg-4670, qld

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SE farm press

Boll Weevil USDA Agricultural Research Service

The weevil: an historical look at the ‘war’ that changed Southern cotton

The boll weevil and its hunger for cotton was powerful enough to forge an unprecedented partnership between farmers, legislators and scientists.

Dominic Reisig | May 18, 2017

The boll weevil is not much to look at – just a grayish, little beetle with an impressively long snout. But this particular beetle, and its hunger for cotton, was powerful enough to forge an unprecedented partnership between farmers, legislators and scientists. And that partnership showed how much can be accomplished when scientists and farmers work together.

What adult boll weevils lack in size they make up for with their larvae’s ability to feed on and destroy cotton. Boll weevils entered the U.S. from Mexico in the late 1800s, when they were first spotted in Texas. By the 1920s they had spread through all of the major cotton-producing areas in the country. The scope of the damage was breathtaking, as were the control efforts thrown at this insect: at one time, one-third of the insecticide used in the U.S. was used to combat boll weevils.

Editor’s Note: This was originally posted on the North Carolina State University website.

In 1903, the chief of the U.S. Department of Agriculture (USDA)

testified before Congress that the insect’s outbreaks were a “wave of evil,” and that afflicted areas in Mexico had abandoned cotton production altogether. Indeed, many scholars agree that the impact was so great on the rural South’s cotton-dependent economy that it was one of the causes of the “Great Migration,” when African Americans moved en masse to the northern U.S. during the early 1900s.Despite the arrival of the boll weevil, cotton production at first actually increased in the U.S., because the price of cotton increased as the boll weevil ran some cotton growers out of business. Cotton production moved in advance of the weevil, creating a boom in cotton plantings in areas that were weevil-free. But as the cotton spread, so did the boll weevil – costing cotton growers billions in revenue.

Declaring War on the Weevil

Then, in 1958, something novel happened. The National Cotton Council of America unanimously agreed, for the first time ever, on a piece of farm legislation. Among other things, that legislation called for cotton research to be expanded – and the boll weevil to be eliminated.

This was an unusual step for many reasons. First, efforts had been made to eradicate insects in livestock before, but no one had ever tried it with a crop pest; this was breaking new ground. Second, this was going to cost a lot of money, which would require the support of the federal government. Third, nobody had yet come up with a way to eradicate the insect. Finally, once eradication began, the eradication process would become a common pool resource. Because of this, cooperation would be vital, given that there would be a temptation for individuals, or whole regions, to get a free ride, relying on the contributions of their neighbors to the eradication effort. So mandatory farmer participation was a must. One by one, each of the challenges were addressed, requiring close collaboration at every step.

Insect eradication was not an entirely new concept. The promoter of eradication was a USDA Agricultural Research Service (USDA-ARS) scientist named Edward Knipling, who had come up with an idea called the sterile insect technique. This technique was pioneered in the 1950s to eliminate screwworm, a parasitic insect pest of cattle. The sterile insect technique relies on flooding the environment with lots of sterile males. Those males then mate with females, but don’t produce any offspring. Knipling now envisioned eradication of the boll weevil, recognizing that it had two chinks in its armor. First, it was an exotic species, which meant that it could be present without some of the parasites and predators that weakened populations in its native Mexico. Second, it was reliant on a single host plant, cotton, which was also not native to the U.S.

Unfortunately, the sterile insect technique bombed. One million sterile boll weevil males were released in a trial. But the sterile males couldn’t compete with their virile wild counterparts and the trial was unsuccessful.

If eradication was going to take place, scientists would have to develop a new method. To that end, the federal government, state governments, and various cotton foundations and associations appropriated millions of dollars to support the research needed to develop the necessary tools for eradication.

For example, Congress funded USDA-ARS laboratories in many states, including one on the campus of Mississippi State University that was critical to creating many of the tools needed for eradication. This support continued through the eradication effort, ensuring that the insect could be eliminated beginning in Virginia and northeastern North Carolina, and moving steadily southward.

But the researchers of eradication faced a significant challenge up front. They knew that, for eradication to be successful, there had to be a very effective method of controlling boll weevils – one with a success rate of close to 100 percent. And that would require a significant leap over the available control techniques.

During the 1950s, controlling boll weevil infestations required multiple applications of very harsh and toxic insecticides (e.g., aldrin, azinphosmethyl, benzene hexachloride, chlordane, dieldrin, toxaphene, malathion, methyl parathion, and parathion). But a separate scientific advance was just around the corner.

New Weapons

In the 1960s, researchers were just beginning to understand the importance of insect pheromones, the chemicals produced by insect species that change behavior of other individuals in the species. USDA-ARS scientists discovered the sex attractant pheromones of the boll weevil – the combination of chemicals that allowed male boll weevils to find female boll weevils. These researchers were able to perfect a synthetic attractant pheromone blend, creating a lure that could be used to trap the amorous boll weevils. This advance would prove to be the linchpin for successful eradication, as weevils could be attracted, trapped, and monitored.

Another major breakthrough was the discovery of a method of control that increased success from 85-90 percent control to 98-99 percent.

Insect development is dependent on temperature, and lower temperatures slow down weevil development and reproduction. Mississippi scientists discovered that, by making multiple insecticide applications at short intervals during the autumn, they could both reduce the last reproductive generation of the weevils and significantly limit the survival of potentially overwintering adults. This was termed the reproduction-diapause control method.

The combination of the pheromone traps and the reproduction-diapause control method meant that, given cooperation on an area-wide basis, the boll weevil might be eradicated. And the pheromone traps cold also be used to confirm whether eradication efforts were successful. This one-two punch was tested in a pilot program in Alabama, Mississippi and Louisiana during the early 1970s. The pilot program couldn’t prove that this approach would eradicate boll weevils, but it was successful enough at reducing population levels that government, industry and research officials opted to proceed with a large-scale approach. This next step involved rolling out two companion trials in the late 1970s: one trial took place in Mississippi using the best known control methods for boll weevil at the time, while another trial tested the reproduction-diapause control method in North Carolina and Virginia.

Cooperation was critical to the North Carolina/Virginia trial. The federal government came through with enough funding to support 50 percent of the trial, while the state of North Carolina agreed to pick up another 25 percent of the cost. And more than three-quarters of North Carolina cotton growers approved of the eradication, agreeing to fund the remaining 25 percent. Meanwhile, a new insecticide had become available, diflubenzuron, which proved to make the eradication even more successful.

After three years, the reproduction-diapause method proved so successful that only one weevil was trapped in the North Carolina/Virginia eradication area. Moreover, this weevil was thought to be left over in a contaminated trap that hadn’t been cleaned properly. Insecticide use plummeted after eradication, but expansion and continuation of the program was not easy. Problems with funding, grower support in new eradication areas, and outbreaks of other pests, resulting from intensive insecticide applications used in eradication efforts – which obliterated beneficial insects that normally kept pests in check – slowed the process However, by 2009, the boll weevil was declared eradicated from all U.S. cotton-producing states, with one exception: Texas, which is the biggest cotton producer in the country.

A Fragile Victory

Which brings us to 2017. Eradication efforts have been stalled at the Texas-Mexico border, largely due to the instability created by illegal drug trafficking. That instability has effectively made large cotton farms in Mexico inaccessible for treatment, creating a welcoming habitat for boll weevil populations to rebound. Another problem in Mexico is the presence of non-cotton plant species that can host boll weevil. Further efforts to limit cooperation across the border, including the proposed border wall, ensure that the boll weevil’s “wave of evil” remains a looming threat. As a result, there is an ongoing battle to keep boll weevils in check in the Lower Rio Grande Valley of Texas, funded by an ongoing annual assessment from cotton-producing states, which is aimed at preventing – and tracking – the spread of boll weevil populations.

But this story also highlights the fact that that the boll weevil has been largely conquered in the U.S., thanks to cooperation among growers, scientists and government officials – and due, in large part, to federal research funding. For example, in the southeastern U.S., a boll weevil has not been captured in a pheromone trap in 14 years. And those federal investments, made across the South, continue to pay dividends in the form of new projects, which are poised to tackle today’s native and invasive insects due to the investments made from boll weevil eradication.

For example, those early investments by state and federal governments created the USDA-ARS research system that is still present today across the southern U.S., including the facility at Mississippi State. This system continues to make a difference for U.S. farms. Research units in areas that still have boll weevil populations are using cutting-edge technologies, such as population genetics and aerial infrared imaging, to track movement of the species and identify potential patches of host plants for destruction. As boll weevils have been slowly eradicated, state by state, these researchers and facilities have shifted research priorities to other issues and pests affecting crop production. No one wants to fight another hundred-year war with a plant pest.

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