Monday, August 25, 2014/ Lincoln (NE) Journal Star
Archive for the ‘Emerging/invasive pests’ Category
Corse Net Infos
Rédigé par Nicole Mari le Mardi 19 Août 2014 à 00:49 | Modifié le Mardi 19 Août 2014 – 12:33
Le fléau de la bactérie, Xylella fastidiosa qui ravage tous les végétaux, des arbres aux plantes, menace la Corse. Devant l’ampleur de la catastrophe potentielle et face à l’inertie des pouvoirs publics, les Nationalistes modérés de Femu a Corsica lancent un appel à la mobilisation des socioprofessionnels. Lors d’une réunion à Riventosa avec les filières concernées, ils ont décidé d’interpeller le préfet et de créer un collectif. Ils donnent rendez-vous le 2 septembre à la faculté de Corte. Explications en vidéo de Jean-Félix Acquaviva, maire de Lozzi et président de l’association des élus de montagne, et d’Agnès Simonpietri, conseillère territoriale de Femu a Corsica.
Plus de 8000 hectares d’oliviers détruits et près de 21000 hectares en quarantaine dans les Pouilles italiennes pour des pertes chiffrées, pour l’instant, à 53 millions €. Près de 150 espèces végétales sauvages et cultivées menacées d’être contaminées. Alors que ses consœurs se cantonnent à une seule espèce, la Xylella fastidiosa attaque tout : oliviers, châtaigniers, agrumes, vignes, chênes, fourrages… et n’épargne même pas les très résistants lauriers roses. Le fléau est d’autant plus redoutable qu’il est difficile à détecter et qu’aucun traitement n’est disponible ! Le seul recours est de couper l’arbre et de le brûler. Après la fièvre catarrhale qui a décimé les troupeaux d’ovins et le cynips qui ravage les châtaigneraies, cette bactérie, qui se propage par les moucherons, les insectes et par n’importe quel plant, promet, si elle n’est pas éradiquée, une catastrophe agricole, économique et environnementale d’une ampleur sans précédent. La plupart des plants cultivés dans l’île sont importés de Sardaigne ou d’Italie, par des professionnels ou des particuliers et, donc, susceptibles d’être porteurs de l’infection.
Devant l’inertie des pouvoirs publics, les Nationalistes modérés tirent la sonnette d’alarme et appellent à la mobilisation générale. Ils ont convié les socioprofessionnels à une réunion informelle, le 18 août à la Casa Pastureccia de Riventosa. En plein boom de la saison touristique, retenus dans leurs exploitations, la plupart, oléiculteurs, castanéiculteurs, maraichers, pépiniéristes… se sont excusés, mais ont envoyé des représentants. Autour de Saveriu Luciani et d’Agnès Simonpietri, élus de Femu a Corsica, de maires ou conseillers municipaux de communes rurales, de membres des chambres d’agriculture, de l’Office national des forêts, du syndicat Via Campagnola, ils ont exprimé leurs inquiétudes et leur détermination. Le président du Sidoc, le syndicat de l’huile d’olive corse, avait, déjà, en octobre 2013, alerté le Préfet de région et le président du Conseil exécutif de l’assemblée territoriale, sur la présence d’un champignon venant des Pouilles. Sans obtenir de réponse.
Déjà infectés ?
L’objectif, dans un premier temps, est de rassembler toutes les informations disponibles sur la bactérie et ses dommages. La première question, qui taraude les intervenants, est de savoir si la Corse est déjà infectée par ce virus qui menace à ses portes. Nul ne le sait réellement. « Sommes-nous certains de ne pas être infectés ? Non ! Des prélèvements sont effectués, mais pas partout ! », assène un membre de la Chambre d’agriculture de Corse-du-Sud. « Je déplore qu’on ne soit même pas en état de dire si la bactérie est présente ou pas en Corse ! Une agricultrice, dans le Sud, nous a parlé d’un champignon et nous a demandé une étude phytosanitaire. Nous attendons les résultats », renchérit un de ses collègues du Nord. « Le risque de contamination est très important. On n’a pas l’impression que les choses ont été prises en main », déplore Agnès Simonpietri, qui rappelle que le gouvernement a refusé d’accorder à la Corse une protection spéciale contre le cynips. Et pourtant, assure-t-elle, « des directives européennes de protection des végétaux permettent aux Etats-membres, qui le souhaitent, de définir des zones protégées ».
Interdire ou pas ?
La 2nde question est : quelle réponse apporter et quelles mesures prendre ? Il paraît évident à tous que les réponses ne peuvent pas être uniquement agricoles. L’une prône le renforcement du passeport sanitaire pour contrôler les importations, notamment sauvages ou individuelles. Mais sera-t-elle suffisante ? Tous en doutent ! L’île ne dispose pas du personnel pour effectuer ces contrôles. La réponse la plus sûre serait l’interdiction simple de toute importation de plants adultes d’Italie, notamment low-cost. A l’instar de ce qui se passe dans de nombreux pays comme l’Australie, les Etats-Unis ou le Mexique. Même si l’interdiction est lourde de conséquences pour les producteurs locaux. « Jusqu’à cette année, les pépiniéristes corses ne pouvaient pas modifier les plants d’oliviers. L’interdiction empêcherait tous les programmes de plantation de se faire. On ne pourra plus planter un seul arbre. La filière ne se développera plus pendant cinq ans, ce qui posera un problème économique », remarque un membre de la Chambre agricole. La discussion achoppe sur les mesures à prendre entre des objectifs contradictoires : l’installation de nouveaux producteurs ou la prévention d’une catastrophe. Et pose, en aval, devant la multiplication des virus en provenance d’Italie du Sud, une vraie problématique : comment développer la production locale pour éviter les importations ?
La création d’un collectif
Au final, les participants à la réunion décident, d’abord, d’interpeler l’Etat, seul compétent en matière de contrôles, et de lui demander de prendre, enfin, ses responsabilités. « Il n’a rien fait pour prévenir la fièvre catarrhale, rien fait pour le cynips ! Là, c’est dramatique ! Si on n’agit pas, tout sera touché », s’insurge un producteur castanéicole. Dans un communiqué qui sera publié prochainement, ils interpellent, donc, le Préfet de région en posant deux questions : « Quelles mesures comptez-vous prendre ? Avec quels moyens ? ». Une cellule oléicole régionale devrait être créée en septembre à la Chambre d’agriculture pour tenter d’y voir plus clair. Face au manque de coordination des socio-professionnels, Saveriu Luciani les exhorte à se rassembler et à s’engager : « Le groupe Femu a Corsica va, à la prochaine session de l’Assemblée de Corse, demander aux élus territoriaux de voter une motion. Mais les motions n’arrêtent rien ! Nous vous apporterons tout le soutien nécessaire, mais l’action doit venir de vous ». Tous, estimant que seule une large mobilisation citoyenne peut empêcher la catastrophe, appellent à un rassemblement à la faculté de Corte, le 2 septembre, pour créer un collectif. Affaire à suivre…
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.
Genetically modified fruit flies deliberately engineered to kill themselves off could help save fruit crops by controlling the pest population without the need for pesticides. That’s the assertion of Oxitec fruit fly team leader Dr. Martha Koukidou, who spoke with www.freshfruitportal.com about the benefits of introducing these flies into the agricultural sector. In opposition is policy research and public interest group GeneWatch. Here, we take a look at both sides.
Mediterranean fruit fly trials are to be carried out in Brazil following official approval for the Oxitec project to take further steps for development.
The National Technical Biosafety Commission, a multidisciplinary body that advises the Brazilian government on biosafety matters, has given the green light for the Oxitec netted field experiments.
The U.K. pioneer in controlling insects that spread disease and damage crops is now putting together further work before those trials actually happen.
Koukidou explains how the current line of defense against pests like fruit flies is insecticides, but the project’s aim is to reduce this usage and save crops as well.
The Oxitec GM fruit flies have a gene which interrupts female development and will only reproduce male offspring.
“We have developed a method whereby you release males in the environment and basically they seek and mate with the wild native females, but all of their daughters will die,” she tells http://www.freshfruitportal.com.
“If you eliminate the females from any given population you are causing the whole population to reduce because it doesn’t matter how many males you have out there, it’s really the females that matter.
“In the case of fruit flies, it is the females that cause damage to agriculture by laying eggs into a fruit, lets say an olive, a peach or whatever else and this egg will develop and hatch larvae, usually maggots; we don’t want to see that in the fruit.
The fruit then becomes prone to secondary infection as the pest tunnels its way through, leaving a hole that is open to bacteria.
“By releasing males and males only that means we do not cause any additional damage to agriculture because the males mate with the wild native females and they don’t affect anything else because the whole method is based on mating.
“They need to mate with the females and by sustained periodic releases, the whole population will drop.
“We believe that this is one of the most environmentally-friendly techniques one can use because it’s totally species specific, does not rely on any chemicals, and does not leave any residue in the environment, the method is self-limiting.”
Koukidou adds that Oxitec has carried out extensive cage separation trials using established wild populations of fruit flies that demonstrated ‘complete elimination of cage population in less than three months’.
“We had excellent outcomes; so the next step for us would be to take those strains into the field.
“We know the term GM causes controversy, however if one looks closely at the technology they will see that it is species specific, it does not affect any other species or anything else in the environment because it relies on mating. And of course we know by default that one species cannot mate with another.”
GeneWatch opposes Oxitec’s fruit flies
GeneWatch director Dr. Helen Wallace has a very different opinion, believing that it’s impossible to predict the long-term outcome possibilities of releasing genetically modified fruit flies into the environment and how, over a period of time, the pests will naturally evolve a resistance to dying off and quite possibly get into the food supply.
“A major concern is that the GM fruit flies are genetically programmed to die at the late larval stage and that will be when many of the flies are still inside when the female lays the eggs,” Wallace said.
“They (Oxitec) already have been approved trials which have not yet taken place, but if those trials take place they will be releasing a GM male to outnumber the wild population by at least a factor of ten to one so we’re talking about millions of GM flies being released and mating with the wild flies.
A key question for Wallace is ‘where will the female offspring that do not survive into adulthood end up?’ and is concerned one possibility could be the food supply.
“Obviously we are concerned about environmental impacts because we’re talking about complex eco systems and a method that is very different from the irradiated flies that they (Oxitec) like to compare it with; so the irradiated ones are sterile, these ones will reproduce and only the females die so male GM adults can survive for multiple generations and it’s almost inevitable that they will spread.
“The technology also uses the antibiotic tetracycline, this is widely used in industrial agriculture and you get high concentrations of it in the environment particularly in animal faeces for example.
“So there is a very real prospect that GM flies will find contaminated areas where they can breed normally and there’s also potential for resistance to develop as the flies evolve. It would be difficult to contain this if anything went wrong.”
Photo: GM sterilization on the horizon for fruit fly fight
Posted in Biological control, Emerging/invasive pests, Insect-plant interaction, Insects, Weeds, tagged IPM Innovation Lab, Parthenium, R. Muniappan, USAID, VA State University, VA Tech, Wondi Mersie, Zygogramma bicolorata on August 22, 2014 | Leave a Comment »
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
Written by Imelda Felix, Finbarr Horgan, and Alex Stuart.
Apple snails (Pomacea spp.) have been a problem for Asian rice farmers for decades. First introduced in the late 1980s to Taiwan and the Philippines, these snails have now spread to most countries in Southeast Asia, as well as East Asia, such as Japan and Korea, where they are among the most damaging pests of rice and other aquatic crops. Recently, established populations of apple snails were found close to major rice-growing regions in Pakistan. India, and Bangladesh. While a few other Asian countries are still free of apple snails, what can these countries expect should the snails someday arrive?
Events in Ecuador might give some clues. In 2005, rice damaged by apple snails was first noticed in Ecuador. Since then, and particularly after severe flooding in 2008, the snail has spread to most of Ecuador’s major rice-growing regions. Losses to the rice sector from apple snails in 2013 alone were estimated at over US$56 million. However, Ecuadorean rice farmers have one big advantage in dealing with apple snails over their Asian counterparts—the snail kite (Rostrhamus sociabilis), a predatory bird that specializes in eating snails.
Flying pest control
The snail kite’s natural range extends from Florida in the United States to subtropical region in Argentina, a region that is also the native habitat of several apple snail species, including the most invasive species: the golden apple snail. West of the Andes, snail kites are largely restricted to mangrove swamps and river estuaries in southern Ecuador, where they likely feed on less invasive snails such as the spike-topped snail.
Prior to the recent apple snail invasion of Ecuador, snail kites were a threatened species. Their population had declined dramatically because of habitat loss and the overuse of agrochemicals. Moreover, farmers often hunted and killed the birds, believing that they damaged livestock. In recent years, as the apple snails have continued to spread, snail kites have become a common feature of the Ecuadorean rice landscape and a welcome sight for farmers. Groups of these birds can be regularly seen perched over rice fields watching for snails, communicating with one another through haunting, rolling caws, or swooping down to catch the snails before gracefully flying off with their prey.
But are snail kites enough to control the snails? We found out that the snail kites first respond to high snail densities by building up their own populations. This means that the snail kites require ample food and suitable habitat for hunting and nesting. Thus, for some time, as the apple snails spread, they escaped the predatory snail kites.
During this time, snail densities peaked, and had terrible effects. A visit to any newly snail-invaded region is a lesson in an ecosystem out of balance: hundreds of bright pink egg masses, containing millions of eggs, can be seen on wooden posts or the trunks of trees near infested ponds and paddy fields. Large patches of rice fields, where the water is deepest, become denuded of rice and other aquatic weeds. Snails, the size of small apples, chew through any remaining green vegetation and decomposing matter at the water’s edges.
Desperate chemical measures
Agrocalidad, Ecuador’s agricultural extension service, has been working with farmers to control snail damage to rice. Experience in Asia had shown that delayed transplanting of rice plants, careful control of water depth, and other cultural control methods could help reduce snail damage. Agrocalidad has shared these methods with tens of thousands of farmers through workshops, talks, theater, videos, posters, and handbooks. However, although Agrocalidad discourages the use of highly toxic insecticides, farmers overwhelmingly used these chemicals, particularly endosulfan, to kill the snails. This reduced snail densities but at high environmental and health costs. Worst of all, farmers noted that the chemicals were also killing their greatest allies—the predatory snail kites. In 2011, the government of Ecuador banned the use of endosulfan, and promoted the use of a more selective molluscicide, methaldehyde—for which the effects on snail kites are still unknown.
Overall, 2013 seems to have seen a decline in snail numbers in some affected areas, particularly in fields at higher elevations. However, a large part of Ecuador’s rice is produced during the dry summer months (June-December) in vegas. Vegas are natural wetlands that are completely flooded for 6 months of the year. In June-July, the water recedes, and farmers track the water levels and plant their rice in a sequential manner in areas of shallow water. This results in an attractive rice landscape with rice of different stages in natural patterns (a system called arroz escalonado or stepped rice). Apple snails in vega systems have remained at very high densities and continue to damage rice significantly. Furthermore, these habitats are highly vulnerable to agrochemicals because they are the natural habitat for a diversity of amphibians, fish, birds, and other fauna and flora.
For scientists, the events in Ecuador are an opportunity to better understand how snails invade rice and how predators and prey interact with each other. Continued monitoring of the situation will highly benefit both scientists and farmers, and could help predict future effects and help design management options as apple snails continue to invade new areas.
Above all, the tremendous negative impact of the invasive apple snail on the Ecuadorean rice sector, despite the presence of a key predator, should encourage snail-free rice-producing countries to be vigilant against possible infestation by tightening quarantine regulations and banning the trade and import of exotic snails. The best way by far to avoid apple snail damage is to ensure that these voracious snails are not introduced to any new regions, where, without natural predators such as snail kites, losses to the rice sector could be even more severe than those experienced in Ecuador.