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Tuancoal (CC BY-SA)/Wikimedia Commons

Do insects feel pain?

On Drive with Richard Glover

It is easy to throw away any sense of empathy when giving a fly a dose of bug spray or stomping on an ant, but should we be more considerate of how these little critters might feel?

Dr Eliza Middleton from The University of Sydney’s Invertebrate Behaviour and Ecology Lab breaks down the known science when it comes to how insects experience pain.

Duration: 9min 2sec

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Genetic literacy project

Ugandan farmers struggling with cassava viruses await GMO solution

Cassava is a major staple food for millions of people in the tropical regions of the world.

In Uganda it is a major food crop for people in East and Northern Uganda. But it is particularly important for people in the West Nile region, with families preparing it as a main course, accompanied by dry fish or smoked beef. It’s prepared with peanut butter, fried beans, green vegetable stew and other sauces.

However, production of cassava is significantly hampered by Cassava Brown Streak Virus (CBSV) and Ugandan cassava brown streak virus (UCBSV), which have devasted yields in the East African region. And farmers are eagerly awaiting new varieties – including the potential for GMO versions – with stronger defenses.

Early this year I traveled to the West Nile region to speak with farmers engaged in growing the crop as commercial venture. A number of them expressed disappointment since most traditional cassava varieties they have been growing have succumbed to the viruses.

Making matters worse is the fact that the hybrid Nase14, once recommended for its ability to stave off CBSV, is losing its effectiveness.

Farmers’ perspective

Abdallah Drasiku is a farmer growing hybrid cassava varieties Nase19, Naro Cas1 and Naro Cas2 on the family’s land in Olali village in Arua District. The 80-acre tract is used for mixed farming – with sections dedicated to maize, tobacco and cassava.

He started growing cassava in 2012 when he planted TME14 on a 12-acre section, but it was severely damaged by the virus. The following year, he planted Naro Cas varieties on a 20-acre tract and he was able to supply over 800 bags of cassava stalk to the National Agricultural Advisory Service. He later milled the processed tuber and obtained 200 bags, each weighing 100kg.

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Cassava damaged by Brown Streak Virus. Image credit: Lominda Afedraru

But the following year, his efforts were again hurt by the virus, destroying his dream of another bumper harvest.

Drasiku is a university graduate who has since embarked on farming as a business and is not thinking of looking for employment. He hopes now that the scientists at the National Agricultural Research Organization will be able to release new GMO cassava varieties to commercial farmers.  Said Drasiku:

“I am aware that our scientists have been breeding GMO cassava variety which has shown resistance to CBSV. However I do not understand the reason why such a crop with viability to increase our income must be released when there is a law regulating it. Is there a way scientists can come up with an option of releasing GMO crops to farmers minus an existing law?”

There is still considerable uncertainty, however, regarding Uganda and GMO crops. The nation’s parliament on October 4, 2017, passed the long-awaited Biosafety Act of 2017. However, the president questioned some sections of the law. It was returned to parliament and the committee responsible for the bill to make amendments. The law is again awaiting the president’s signature.

Farmers in West Nile no longer look upon cassava as simply a subsistence crop. They see it as a viable commercial crop. The demand is increasing in refugee camps in the region and neighboring countries, Democratic Republic of Congo and South Sudan.

He is ready to embrace new hybrid crops developed by NARO scientists – including GMO varieties.

“At the moment my major source of income is from selling cassava stalk and cassava flour processed from hybrid varieties. I am sure the GMO variety has the potential of giving maximum yield since it is resistant to CBSV.”

He is aware of applied science in breeding hybrid cassava varieties which farmers have planted and people have consumed it and this applies to GMO cassava and other GMO crops. To him, what is important to note is that farmers will have the option to choose whether to grow GMO crops, hybrid or the traditional varieties.

Robert Cwinya Ai is another farmer, who has benefited from hybrid cassava varieties.

He planted Nase14 and Naro Cas1 on 6 acre land in 2015 and so far he has sold cassava stalk worth 350 bags to NGO’s distributing to refugees settled in the district.

But he argues that the harvest from these hybrids is not sufficient, since some plants tend to succumb to CBSV:

“I have been in touch with agronomists from Abi Zonal Agricultural Research and Development Institute (AbiZard) in Arua because they advise farmers about cassava disease management. When we spot whitefly which spreads the virus, we try to spray them with chemicals which are costly. We need an appropriate solution and that is release of GMO cassava variety.”

Scientists from NARO have educated the farmers about the importance of growing cassava with readily available market in brewing industries.

In Uganda, ethanol is being used to make alcoholic drinks, fuel and solvent. Ethanol produced from cassava is a better alternative for gasoline, promises cleaner combustion, promotes a healthier environment and is economically viable.

The starch from cassava is also used in the industrial sector to make glue, animal feeds, paper, plywood and textiles. To Cwinya Ai growing GMO cassava would help farmers meet the demand from those industries.

Legislator’s perspective

One of the area legislators, Denis Lee Oguzu, who seems opposed to the GMO bill notes that “the innovations by NARO scientists including application of modern biotechnology are good because farmers are able to grow crop varieties on commercial basis. My only concern is that let NARO scientists take the lead in sensitizing farmers about this technology,”

He notes that amendments must be done for the law to address concerns regarding industrial biotechnology, environment and pharmaceuticals.

GMO cassava Polination 5 4 18 2
Image credit: Lominda Afedraru

Breeding of GMO cassava

The need to stay ahead of various viruses that threatened cassava has been an ongoing endeavor throughout the region. East Africa CBSV, which leads to rotting of cassava tubers, was first reported in Tanzania in 1936, followed by Kenya in 1950 and Uganda in 2004, said Dr. Titus Alicai, head of root crops at the National Crop Resources Research Institute (NaCRRI).

Farmers also have faced Cassava Mosaic Virus, which causes yellowing and wrinkling of cassava leaves thereby affecting growth of the tuber.

Developing a GMO variety has been an ongoing effort since 2006, through a regional established partnership with the Virus Resistant Cassava for Africa (VIRCA).

VIRCA is a collaborative research and development program established by the Donald Danforth Plant Science Center in the US, the National Crops Resources Research Institute (NaCRRI) Uganda and the Kenya Agricultural and Livestock Research Organisation (KALRO).

Breeding work is ongoing both in Kenya and Mubuku Irrigation Scheme in Kasese where scientists are selecting varieties resistant to both CBSV and CMV for distribution to farmers in the near future.

Dr Andrew Kigundu, project manager of VIRCA said the breeding effort obtained genes from cassava variety called TME204 with resistant genes which have were introduced to Nase14 and 19 varieties. Scientists planted the transgenic variety in Kasese at the field trial site alongside Nase 14, 19 and 3 which has resistance to CMV.

Breeders pick up flowers from the resistant varieties and rub against flowers of other varieties. The seed was left to grow and later harvested for processing.

Cassava plantlets have been grown from the generated seed in greenhouses and transplanted in fields. It has shown promising results with resistance to both diseases.

Lominda Afedraru is a freelance science journalist in Uganda who specializes in agriculture, health, environment, climate change and marine science. Follow her on the Daily Monitor web site www.monitor.co.ug, Facebook or Twitter @lominda25

 

 

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By: Nala Rogers, Staff Writer

Inside Science

May 2, 2018

Sick Plants May Attract Distant Bacteria as Medicine

New study shows how sand sedges lure beneficial bacteria to their roots.

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This experimental setup allows researchers to place bacteria at the ends of the glass tubes, then measure how much bacteria moves toward the plants.

Image credits: Kristin Schulz-Bohm

Rights information: This photo can be reproduced only with this Inside Science article.

Wednesday, May 2, 2018 – 12:15

Nala Rogers, Staff Writer

(Inside Science) — If there were a prize for long-distance, interspecies communication, few people would think to nominate a bacterium and a scraggly, grasslike plant. But according to a recent study, the roots of one such plant can call bacterial allies several inches away — a veritable marathon for tiny soil bacteria. Preliminary data suggest that the plants may even adjust their messages when they get sick, calling in different bacteria to act as medicine.

Scientists already knew that plants send signals above ground to communicate with animals. Flowers, for example, attract bees and other pollinators using color and scent. Some plants also use scent chemicals to call for help when they are attacked by plant-eating insects, luring in parasitic wasps that attack the insect herbivores.

But comparatively little is known about how plants communicate with microbes below ground. Plants rely on a complex microbiome to help them obtain nutrients from the soil, but most research on plants and soil microbes has focused on interactions that happen right at the edges of plant roots, said Paolina Garbeva, a microbial chemical ecologist at the Netherlands Institute of Ecology in Wageningen.

Garbeva and her colleagues suspected that plants use volatiles — substances that easily evaporate and can diffuse through air and water — to send long-distance “scent” messages belowground as well as above. In a study published this past January in The ISME Journal, they collected and analyzed the volatiles released by sand sedge roots, and then tested how bacteria responded to those volatiles.

To test the responses of bacteria, they filled glass cups with sterilized soil that contained no living bacteria, and used some of the cups to grow sand sedge plants. Each cup was connected to four horizontal glass tubes about 4 inches in length, which were also filled with sterile soil. The researchers placed a mixture of bacteria at the outer ends of the tubes, then measured how much of each strain of bacteria traveled through the tubes toward the cup.

Cups that contained plants attracted up to three times as many bacterial cells per strain as cups without plants, suggesting that bacteria were detecting the plants’ presence from 4 to 5 inches away, said Garbeva. The bacteria were presumably responding to volatiles released by the plants’ roots, since only volatile compounds could effectively diffuse so far through the soil, she said.
Next, the researchers infected some of the plants with a fungal disease. The infected plants released a different mix of volatiles from their roots, which in turn attracted a different suite of bacteria. When the researchers grew these bacteria in petri dishes with the infectious fungus, they found that the bacteria halted the fungus’s growth, raising the tantalizing possibility that the plant was recruiting specific bacteria as medicine.

The medicine-recruitment idea is still highly speculative, noted Garbeva. She and her colleagues are currently testing whether the bacteria attracted by sick plants can effectively combat the disease on the plants themselves. They have not yet compared the antifungal properties of the bacteria attracted by sick versus healthy plants, so it’s possible that healthy plants’ bacteria are just as good at stopping the fungus.

Moreover, these types of ecological processes are often context-dependent, said Sergio Rasmann, an ecologist at the University of Neuchatel in Switzerland, who was not involved in the study. If the researchers were to repeat their experiments while changing something like temperature or humidity, he said, they might get different results.

Nevertheless, the results are “very exciting,” said Rasmann. “The idea of plants recruiting microbes is not completely new. But the fact that they actively produce some chemicals in the soil to attract them — that’s very new,” he said.

Garbeva hopes that by examining the types of bacteria plants attract in nature, scientists may someday identify strains that could be added to crops as probiotics. Different strains may help with particular problems such as disease or drought, she said.

“Soil has the highest microbial diversity in the world,” said Garbeva. “We can find how plants can attract bacteria that are beneficial for them, and maybe we can use these bacteria in the future for plant protection.”

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Author Bio & Story Archive

Nala Rogers is a staff writer and editor at Inside Science, where she covers the Earth and Creature beats. She has a bachelor’s degree in biology from the University of Utah and a graduate certificate in science communication from U.C. Santa Cruz. Before joining Inside Science, she wrote for diverse outlets including Science, Nature, the San Jose Mercury News, and Scientific American. In her spare time she likes to explore wilderness.

 

 

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Report shows growth for agriculture, but sector still faces hurdles

Children help out in a field in Kampong Speu province in 2015.

Children help out in a field in Kampong Speu province in 2015. Victoria Mørck Madsen

 

The total export of agricultural products rose to 5.13 million tonnes last year, up from 4.7 million tonnes the year before, a sign that the sector was on the right track according to Agriculture Minister Veng Sokhon.

Speaking on Monday at the release of the ministry’s 2017 annual report, Sokhon said that while farming in Cambodia had seen remarkable growth in the past few years, more work needed to be done to increase exports, ensure crops were processed in the country and increase compliance with health and safety standards.

“Our sector still faces a lot of challenges, and we need to discuss and seek the solutions in order to match with the government policy on the developing agriculture sector,” the minister said. “How do we intervene to increase productivity, quality, and safety in order to respond to market needs?”

Rice exports grew by 17.3 percent to reach 635,697 tonnes last year, while rubber also expanded by 30.14 percent to reach 188,832 tonnes, according to the report.

Widespread smuggling continues to account for much of the country’s agricultural trade. More than 40 percent of Cambodia’s rice exports go through informal channels according to a recent UN estimate, while rubber plantations and processing companies have complained that small-scale farmers get higher prices for their crops by selling to Vietnamese brokers instead of complying with Cambodia’s tax laws.

Sokhon did not mention smuggling in his speech on Monday.

The export of cashew nuts grew 20 percent last year to 87,853 tonnes according to statistics provided by the ministry, although information about the cashew sector was not included in the report.

The government announced a plan in January to export 1 million tonnes of cashews by 2028 with the help of the Vietnamese government, but no plans have been released about how that target would be reached.

 

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Ghana News Agency

http://www.ghananewsagency.org/science/ghana-to-focus-on-bio-rational-products-for-management-of-faw-131321

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Ghana to focus on bio-rational products for management of FAW

By Belinda Ayamgha, GNA

Accra, April 13, GNA – The Ministry of Food and Agriculture says it has shifted its focus from synthetic insecticides to bio-rational products, for the management of the Fall Armyworm (FAW) infestation, as part of its short, medium and long-term management measures.

The focus on bio-rational products is to ensure minimum pest resistance by the FAW, which is higher with the use of synthetic insecticides.

Dr Mrs Felicia Ansah, Director of Plant Protection and Regulatory Services at MoFA, said this when she briefed Journalists on the current situation of the FAW problem.

She noted that the FAW had come to stay, as it could not be completely eradicated but managed, as in the case of Brazil, which had been managing the FAW infestation for the past 40 years, and was currently one of the biggest exporters of maize.

Ghana had thus modelled its management measures after the Brazilian experience.

These measures, she said, include the deployment of pheromone trap catches in various locations across the country to ascertain the levels of infestation, training of MoFA staff and farmers on scouting, early detection and sustainable management of the pest in the event of an outbreak.

She explained that the best way to manage the infestation on farms was to detect the pests early at the larvae stage, and not when they became full grown moths. That is when they did the most damage to crops.

Other measures being undertaken by the Ministry are the distribution of pesticides to all district offices in the country where farmers can access in FAW infestations, the formation and training of Nnoboa Spraying Teams in farming communities and intensification of public awareness creation for farmers and the general public.

According to Dr Ansah, Ghana had commenced scouting of natural enemies of the FAW, which once identified, will be reared to help reduce the population of the pests.

“In the long term, only biological control agents, microbial insecticides and botanicals/organic products will be used to manage FAW in Ghana,” she said.

She said a total of 249,054 hectares of maize were affected and sprayed, out of which 234,807 hectares recovered and 14, 247 totally destroyed in the previous season, adding that there was a likelihood for more infestations in the 2018 farming season.

Dr Ansah stressed the need for the media to be circumspect in how they reported issues around the FAW infestation as it had implications for trade.

She urged the media to collaborate with the Ministry to educate farmers on how to manage the FAW.

She said the pockets of FAW infestations being currently experienced in some districts in the Ashanti, Brong-Ahafo, Eastern, Volta and Western Regions had been blown out of proportion as it was a pre-season production infestation.

“We would like you to appreciate that this is a Phytosanitary or Public Plant Health Issue, with trade implications and must be communicated in a professional manner. Media coverage should rather be geared towards improving the knowledge and skills of our farmers,” she said.

GNA

 

 

 

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Exploding ant

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New ‘exploding ant’ species also blocks invaders with its massive head

ABC Science

Anyone who’s accidentally stood on an ant nest will know just how good they are at defending their home, but a new species of “exploding ant” takes it to the next level.

When confronted by an enemy insect, these tree-dwellers latch onto their foe, tear open their own body wall and release yellow toxic goo onto their rival, slowing or killing it.

And while this “explosion” doesn’t exactly blow them to bits, it also spells the end for the defending ant, said Alice Laciny, a PhD student at the Natural History Museum in Vienna.

She and her colleagues discovered the new species, dubbed Colobopsis explodens, in the rainforests of Borneo and their findings were published today in the journal ZooKeys.

“It’s a bit like the mechanism of when a bee stings,” she said.

Such “suicidal defence” is only common in social insects, such as ants, bees and termites, she added.

“An ant colony shouldn’t be treated as a family of individuals, but really like a super organism, and each ant acts more like a cell in a body and it has its own role to play.”

Active and passive resistance

This explosive behaviour was first described in an ant species from Singapore in 1916, but it’s a rare ability — and no new exploding species have been described since the 1930s.

What’s more, it’s only the minor workers in a C. explodens colony that are capable of self-detonating.

Their body is filled with long glands, which hold the sticky goo. When they contract their backside hard enough, the liquid oozes out, like toothpaste squeezed from a tube.

But many ant species are polymorphic, according to Alan Andersen, an ant ecologist at Charles Darwin University.

“This means the workers come in different shapes and sizes.”

C. explodens is no exception. Where minor workers look like a pretty normal ant, the beefier major workers have a relatively gigantic head.

“The entrance to their nest is a small hole, pretty much exactly the same diameter as the head of the major workers,” Ms Laciny said.

“So they actually just stick their head in the hole and plug it up, so nothing can get inside.

While Australia doesn’t host any exploding ants, we do have a few species with so-called “plug head” members, Professor Andersen said.

A coastal species — Camponotus anderseni, named after Professor Andersen — lives in the twigs of mangroves in the Top End.

“Their nests are inundated by the tides every tidal cycle, so the nest of these ants is underwater for large periods of time every day.”

When the tide comes in, plug-head ants wander up to the entrances and lodge their head in to create a water-tight seal.

It’s such an effective way to keep stuff out of the nest — whether it be invading insects or the ocean — that plugging behaviour has independently evolved over and over again.

A slightly different plugging action is carried out by some ant species in the US, Professor Andersen said.

These drop stones in the entrances of a more-dominant ant species, effectively trapping them inside until they can bust their way out.

More bizarre but brilliant behaviours

Another group of ants with an incredible defence mechanism found in Australia is the trap-jaw ants, said James Cook University ant ecologist Lori Lach.

These sport a pair of long, straight mandibles that are usually held open until tiny trigger hairs on the inside of the mandibles are tripped and the jaw snaps shut.

“It’s helpful to capture prey, but it’s also been documented that if they’re threatened, they snap them against the ground.

“The force propels them to flip away. They essentially do backflips away.”

Along with plug-heads, exploders and backflippers, some ants have also found ways to avoid threats from above.

Leafcutter ants must contend with parasitic flies, which lay their eggs on ant heads, Dr Lach said.

“When the egg hatches, the larvae burrow into the ant head and eat it from the inside out.”

So when foraging leafcutters head out above ground, they need a bodyguard.

This comes in the form of a tiny worker ant which sits atop the leaf, Dr Lach said.

“They’re there to shoo away the flies that might come and lay their eggs on the heads of the larger ants.

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