By Fiona Emdin. Reblogged from the CGIAR CCFAS blog. Different doctors treat different types of diseases. When the villagers of Rohal Suong in Cambodia feel sick, they can consult a doctor. Now when their crops are sick, they can also go to another doctor, a plant health advisor, who can provide information on the best […]
Archive for the ‘Pest diagnostics’ Category
When Jon Eisenback, professor of plant nematology at Virginia Tech’s College of Agriculture and Life Sciences, conducted nematode surveys on vegetables and rice in Cambodia this past August, one of the most surprising things he encountered in the vegetable fields was, in a word, nothing.
“One of the biggest finds from that trip was almost completely sterile soil,” Eisenback said of the surveys he and postdoctoral associate Paulo Viera conducted in vegetable farms near Siem Reap.
They visited farms growing cucumbers, sweet melons, eggplants, tomatoes, and cantaloupes to assess whether any of them were suffering from nematode invasions, but they found that all the crops were grown under plastic with drip irrigation. They had been covered with so many pesticides that there was nearly nothing living – the soil was essentially ruined.
Jon Eisenback, second from right, professor of plant nematology at Virginia Tech’s College of Agriculture and Life Sciences, testing soil in the fields of Cambodia with postdoctoral associate Paulo Viera, second from left.
Plant parasitic nematodes are microscopic roundworms that cause significant damage to many crops. In Cambodia, a country with nearly half of its labor force in agriculture, nematodes can create big problems for food production.
Because of our program’s focus on biocontrol and biopesticides to alleviate agricultural pest problems, Eisenback said that the vegetable IPM project would increase chances that vegetable farmers in Cambodia would stop the soil-killing overuse of pesticides.
After surveying the vegetable fields in the north, Eisenback and Viera traveled to the south of the country to conduct nematode surveys on rice. Given the dearth of scientific literature published on nematodes in Cambodia relating to rice, Eisenback and Viera weren’t sure what to expect. However, they found that the rice fields they surveyed showed a significant loss of production caused by the rice root nematode.
“Every root we looked at had lesions,” Eisenback said. The culprit was a parasitic nematode called Hirschmanniella mucronata. “Rice roots should be creamy white. These were speckled with brown and orange lesions.”
Eisenback expects that these nematodes could cause a 20 to 30 percent crop loss of rice in affected fields.
The next step is field demonstrations; to undertake them, half the fields should be treated with nematicide to measure the effect. Eisenback also said he hopes to continue the survey to see what other nematodes are there.
“I would suspect that there are other fields with other nematode problems.”
As for the vegetable fields with the sterile soil near Siem Reap, Eisenback offered a recommendation for them as well: Don’t use so many toxic pesticides.
With IPM IL’s projects up and running in the region, that should soon become less of a problem.
Halyomorpha halys now affecting apple orchards in Piedmont
The brown marmorated stink bug (Halyomorpha halys) is not the only harmful pentatomidae that can be found in orchards, so it is very important to be able to recognise the other species as well. Agrion technicians have therefore prepared the table below to make them easier to recognise.
H. halys compared to other bugs
In the Piedmont area, this insect has two generations a year and spends winter in sheltered environments such as houses, warehouses, etc. Due to this year’s mild weather, it managed to survive even in the fields.
Graziano Vittone, Agrion technical coordination manager, warns producers about the brown marmorated stink bug. “Now that the peach season is ending, you must monitor your apple orchards. Inspect the trees, especially the upper foliage, or shake them after placing a film underneath to count how many fall to the ground. These are both time-consuming operations, but they enable growers to assess the problem.”
“You must intervene as soon as you notice the insect on the outer trees as, if it colonises the orchard, it will be too late and most of the produce will be damaged.”
In all other cases, it must be stressed that bugs reach apple orchards from kiwi trees, peach orchards and cereal crops, so the edges must be constantly checked and protection barriers must be put in place.
Agrion -Fondazione per la ricerca l’innovazione e lo sviluppo tecnologico dell’agricoltura piemontese
Via Falicetto, 24
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Delta Farm Press
A new mobile-friendly field guide will help farmers quickly diagnose soybean diseases, like Septoria brown spot (shown in image), in their fields. It can be found at guide.utcrops.com.
The University of Tennessee Department of Entomology and Plant Pathology has released a mobile-friendly disease field guide that will help growers, agents and consultants quickly assess foliar diseases in their soybean fields. This new resource can be found at http://www.guide.utcrops.com.
The guide features general information on all foliar diseases that pose an economic threat to Tennessee’s soybean crop.
Proper identification is made easier through video instruction and a comprehensive photo gallery. These features allow users to easily compare what they are seeing on the screen with what they are seeing in the field.
Once the problem is identified, users can view management options for each disease, including information on variety selection, fungicide efficacy and resistance.
Heather Kelly, assistant professor with UT’s Department of Entomology and Plant Pathology, designed the new guide. Her goal was to create an informative site that would look great and function well on the devices most growers are using — smartphones.
“This guide should make it easier for producers to quickly identify diseases and make management decisions,” says Kelly, “and since it’s mobile friendly, it will also be user-friendly when producers access it in the field.”
While the guide currently features only soybean disease information, Kelly says the site will eventually include information and identification tools for diseases that affect other row crops. She adds that the mobile friendly guide can also be easily viewed on a laptop or desktop computer.
Three resources on line for weed identification. All from the US. This is taken from “Help with weed identification” http://www.whav.net/cms/help-with-weed-identification/
Start with University Weed Identification sites such as those at Michigan State University (http://www.msuturfweeds.net/id-tool/broadleaf/), The University of Missouri (http://weedid.missouri.edu) and New Mexico State University (http://weeds.nmsu.edu/weedid.php).
Drones could be the answer to early disease detection in banana crops
A researcher is looking into the possibility of using remote sensing to detect diseases in banana crops.
University of New England PhD candidate Aaron Aeberli said different sensor systems could be attached to satellites or drones.
“Remote sensing records the interaction of different objects to different levels of electromagnetic radiation systems,” he said.
Mr Aeberli said the technology was already being used in other crops such as sugar cane, wheat, cotton and peanuts.
“A lot of the broadfield cropping systems have used them overseas to find out yield and other predictions like that,” he said.
“There’s potential to find out the health of the different plants, and if we can work on it enough, the potential to detect disease occurrence.”
Diseases could be detected early through the application of thermal imaging.
“It uses a different part of the spectrum to monitor the warmth or heat of the object, and a lot of plants, their function is impaired by disease, particularly the heat or thermal regulation,” Mr Aeberli said.
“There is potential to notice changes in the leaf temperature if the plant is no longer able to function normally.
“Some of the bigger crops like wheat, they use it a fair amount and it does save them time. It can help with production and management systems.”
Technology to be trialled in Queensland
Mr Aeberli is hoping to develop the technology further for the banana industry.
He is collaborating with the Queensland Department of Agriculture and Fisheries and Horticulture Innovation Australia on upcoming trials in far north Queensland.
“We’re looking to take some satellite imagery and we’ll go into the field and try and evaluate this satellite imagery, so that the field conditions reflect what we’ve been taking from the satellites,” he said.
“We’re also looking at the use of UAVs (unmanned aerial vehicles) for a similar system.”
There could be potential for banana growers to one day monitor the health of their own crops by drones.
“It’s early days so we need to work out what systems work,” Mr Aeberli said.
“I wouldn’t necessarily go out and tell everyone to buy a drone at this point in time, but once a valid system that works has been set up, there’s potential for that.”
SAO JOSE DOS CAMPOS, Brazil (Thomson Reuters Foundation) – Despite years of experience, Charlei Sousa finds himself struggling to grow maize. A lack of rain took half his last crop, and he says uneven rainfall has for years become a worsening problem in his fields in Montes Claros.
“We don’t know anymore how and when to grow,” said Sousa, a family farmer who plants about 30 hectares (74 acres) of maize in the north of Minas Gerais state, which lies within a semi-arid region of Brazil.
Changes in weather patterns linked to climate change are challenging the traditional knowledge of family farmers in Brazil, particularly those in traditionally dry areas of nine northern states, where land is used mainly to grow subsistence amounts of maize, rice, beans and cassava.
But help may be on the way. This season, Sousa will take a new ally to the field with him: a smartphone app. Used as a sort of in-field diary, it will record what is planted and when, how much fertilizer is used, geographical data about the field, photos and other details.
A few hundreds kilometers away, in São José dos Campos, in São Paulo state, scientists receive the data in real time. The information produced by Sousa and other family farmers will feed a new system designed to monitor the risk of crop failure in Brazilian semi-arid areas.
“There is no such monitoring being done in real time, with information coming directly from the producer,” said Ana Paula Cunha, a researcher at National Center for Monitoring and Early Warning of Natural Disasters (Cemaden).
The center, together with Applied Systems Analysis and the National Institute of Science and Technology, developed the app called Agrisupport.
With the help of farmers, scientists at Cemaden say they will be able to predict up to two months in advance whether the semi-arid region faces a risk of crop failure.
Alongside the information from farmers, researchers will rely on measurements of humidity, temperature, wind and solar radiation coming from monitoring equipment installed in nine states.
Those will be fed into mathematical models that researchers run on the institute’s computers, and turned into forecasts for farmers and others in Brazil.
“We want to provide information about the crop productivity loss for all municipalities of the semi-arid region,” said Regina Alvalá, a coordinator at Cemaden. The first report is expected to be available by the end of 2016.
PLANNING FOR PAYOUTS
The forecasts are expected to be particularly important for the federal government. Since 2003, Brasilia has offered financial compensation for family farmers from semi-arid regions who lose at least 50 percent of their crop. This type of insurance is known as “crop-guarantee”.
“For the decision maker, information on the risk of crop failure is vital because it is possible to have a better view of how much will be paid for insurance,” Alvalá said.
“But the information is also relevant to the producer,” she said. “For example, if a farmer wants to extend the planted area but the forecast shows the weather conditions won´t be good enough for the type of crop raised, the farmer can save the seeds.”
According to government data, around 63,000 family farmers applied for crop-guarantee insurance payouts last year. The government provides 850 Brazilian reais (around $215) per producer, paid in five installments. But many farmers complain the amount is too low and doesn’t cover their costs.
Access to the Agrisupport app could be another way of cutting farmer losses in dry areas. Reinaldo Oliveira, an agronomist at Technical Assistance and Rural Extension (Emater), a state agency, is working directly with farmers to help them use the tool.
“The mobile phone is already used by family farmers on a daily basis. But to send information through the app it’s also important to have a good internet connection, which is not always possible in some regions,” he said.
Still, farmers able to send through a photo of a crop pest, for instance, can get feedback on what do about it in as little as a few minutes, Oliveira said.
Sousa has already tested the app. Besides providing information about what he’s planning to grow and how much of it, he will also report on his harvest and receive advice on how to take better care of his crop.
“I think this application will help small farmers to organize themselves better. We shall know in advance which is the best time to start planting. This information can help us to save money,” Sousa said.
(Reporting by Nadia Pontes; editing by Laurie Goering :; Please credit the Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, climate change, women’s rights, trafficking and property rights. Visit news.trust.org/climate)