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Archive for the ‘Plant breeding’ Category

Lentil breeding advances set to continue

North Queensland Register

Gregor Heard

Gregor Heard@grheard20 Oct 2021, 3 p.m.Grains

Agriculture Victoria lentil breeder Arun Shunmugam with a promising line of yet to be commercially released lentils in a trial at the pulse trial site at Propodollah, near Nhill, last week.

 Agriculture Victoria lentil breeder Arun Shunmugam with a promising line of yet to be commercially released lentils in a trial at the pulse trial site at Propodollah, near Nhill, last week.Aa

IN A YEAR with many contenders for most lucrative crop lentils are making a solid charge.

Values are in excess of $1000 a tonne, primarily in light of a lack of product from the world’s largest exporter of the legume, Canada, and an easing of tariffs from the world’s largest importer, India.https://7d116f708d3262b63c59ece0b6732cc5.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

RELATED: New field peas

It has farmers in the lentil belt through Victoria and South Australia excited about this year’s harvest, with a kind season in regions such as the Wimmera meaning many crops are displaying outstanding yield potential.

Given the buzz around the crop at present it is no wonder lentils were one of the major talking points at last week’s Southern Pulse Field Day near Nhill in Victoria’s Wimmera.

Agriculture Victoria pulse breeders Jason Brand and Arun Shunmugam said there were a number of promising new developments in the lentil breeding pipeline.

In particular two cultivars yet to be commercialised are performing well in trials, with Dr Brand saying there was huge yield potential in the two lines.

Dr Shunmugam said other focuses of breeders included looking to incorporate more frost resistant genetic material along with further advances in herbicide resistant and tolerant varieties.

The crowd at the Nhill field day said Clearfield / imi-tolerant lines such as Hallmark and Hurricane were popular as they gave flexibility within the rotation and reduced the plant-back risk when planted following another Clearfield line.

Dr Brand said frost and waterlogging tolerance remained two key objectives.

He said there was a complex interaction which meant plants just metres apart could fare vastly differently.

“You can see even in the trials here that some plants look like they’ve incurred frost damage and just a couple of metres away with slightly different soil type and slightly higher up they are unaffected.

“Some form of tolerance to both these stresses would be a great win for the industry,” Dr Brand said.

He said the breeding sector wanted feedback from growers about what herbicide tolerance traits were wanted.

“It is a complex one as we have to manage market expectations and maximum residue limits in with what is going to work well agronomically, but we’re really keen to hear what growers would be interested in seeing in future varieties,” he said.

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The story behind the 100% public GM bean reaching Brazilian plates

Daniel Norero | August 31, 2021

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Common bean. Credit: Portal Voz da Comunidade
Common bean. Credit: Portal Voz da Comunidade

This article or excerpt is included in the GLP’s daily curated selection of ideologically diverse news, opinion and analysis of biotechnology innovation.In some Brazilian supermarkets, it is already possible to buy a new genetically modified (GM) common bean, which bears the corresponding GM labeling as required by local regulations. Nothing about this event would be news, considering that Brazil is the second global power in the production of GM crops after the United States and has seen its stores full of products with GM labels. However, this new bean isn’t another of many GM corn and soybeans typically created by North American companies, but rather a 100% locally developed crop by scientists from a state-owned company in the Amazonian giant.

The journey for this new biotech bean to reach Brazilian markets was long and not free of obstacles. It began in the search for a solution to the troublesome Bean Golden Mosaic Virus (BGMV) that can wipe out more than half of a farmer’s bean plants. This pathogen is transmitted by the whitefly, and causes losses estimated at 300,000 tons per year, enough to feed 15 million people.

“BGMV is a serious problem in tomatoes, soybeans and other plants, but in beans it’s also transmitted by whiteflies in a persistent way. When the insect already acquires the virus, it begins to transmit it throughout its life,” says Francisco Aragão, senior researcher at the Brazilian Agricultural Research Corporation (EMBRAPA) and co-creator of the new Brazilian GM bean. “That is why it is difficult to develop a resistance strategy and it’s also known that if you have only one whitefly per plant, you can already have 100% infection.”

Dr. Francisco Aragao (right) and Dr. Josias Faria (left), “fathers” of the Brazilian GM bean. Photo taken in January 2020 in a GM bean field in the city of Río Verde, Goias state. Credit: Francisco Aragao.

Before the new GM bean, the only BGMV control methods were cultural management, biological control, and the use of pesticides to control the virus host -the whitefly- with little results. “The average application [of pesticides] in a season is 10 times, but there are producers who apply 20 times or more. Even with those apps it is still possible to lose everything on some occasions. And if there is soy nearby, it will be very difficult to control the whitefly population in your beans,” says Aragao.

“The prices of insecticides are very expensive and for small farmers it’s difficult to have to use it so many times. In Brazil we have a very large area -about 1.2 million acres- where it’s not recommended to plant beans due to the great loss probability”.Follow the latest news and policy debates on agricultural biotech and biomedicine? Subscribe to our newsletter.SIGN UP

Not just for COVID: RNA also protects crops

Since the 1960s, EMBRAPA researchers have searched for bean cultivars with natural resistance to BGMV throughout the Americas, but results were unsatisfactory. Once only cultivars with only partial resistance and not adapted to Brazilian conditions were identified, EMBRAPA decided to invest in modern biotechnology and GMOs.

“This started in the 90’s when we began to try, on the one hand, to transform beans, which is still one of the most difficult plants to be genetically transformed, and on the other, to study the virus and develop strategies to obtain resistant plants,” Aragao relates. Together with his colleague, Josias Faria, they tried some biotechnological strategies such as antisense RNA -expression of the complementary RNA strand of a gene- and lethal transdominance -expression of a mutated protein that is essential for virus replication-, unfortunately without results or only partial resistance.

“With RNA interference technology, we started in the early 2000s,” Aragao says about RNAi, a natural defense mechanism in plants that “silences genes” but that wasn’t yet fully understood then. Despite this, in the 90’s there had already been success with the Hawaiian papaya, where genetic modification through interfering RNA would save the island’s farmers from the papaya ringspot virus.

How does it work? You’ve probably read or seen a lot in the headlines of the last year about RNA vaccines for COVID-19. In this case, the modifying mechanism with interfering RNA isn’t very different, and it literally works as a “vaccine” for crops. Scientists inserted a DNA fragment of the virus into the nuclear genome of the plant, with the aim of making it produce small double-stranded RNA molecules -known as small interfering RNA or siRNA- that silence the viral rep gene, a key gene for the virus’s replication cycle. As a consequence, the virus is unable to express this gene, its viral replication is interrupted and plants become resistant to the virus. In simple terms, you get a plant “vaccinated” against BGMV.

So in the future, not only will we protect ourselves from pandemics with RNA vaccines, our food can also be protected from deadly viruses with this technology.

It should be noted that this “gene silencing” method is a plant natural mechanism. A normal bean plant that is infected will generate siRNAs later, but not in conditions or levels to deal with the pathogen. With genetic engineering, scientists anticipate and adapt this natural system so that it is triggered the moment the virus enters the plant and it defends itself effectively.

“Something we observe is that flies acquire the virus from plants, but the virus doesn’t replicate in the fly, but in plants… and so the flies acquire more and more viruses,” adds Aragao. “We also observe that when viruliferous flies are put on modified plants, the viral load decreases in the fly, since it releases the virus and has no place to absorb more.”

“It’s interesting and we observe that the same happens for neighboring -not modified- plants”, Aragao indicates, about a potential protector effect that modified beans would have on neighboring conventional crops. “We hope that farmers who produce conventional beans alongside GM bean farmers will also benefit.”

Comparison between an elite line of GM bean resistant to BGMV (right) with healthy leaves and pods, and its conventional counterpart (left) with marked roughness and chlorosis, as well as deformed pods caused by BGMV. Credit: Souza, 2018

From the laboratory to the field

In 2004 the Aragao and Farias team developed the first bean plant immune to BGMV with the siRNA strategy. From 24 modified lines in total, two were immune, and line “5.1” was finally selected–so named since it derives from experiment number 5. “Then we began to do the greenhouse trials, after field trials, the biosafety analyzes and we generated all the data needed to answer all the questions from the National Technical Commission for Biosafety (CTNBio)”, says Aragao.

Aragao and Faria’s team demonstrated that this new GM bean was safe for human consumption, nutritionally equivalent, and had no effects on the environment different than conventional beans. For example, off-target or epigenetic effects were ruled out, and it’s important to note that the inserted transgene doesn’t generate any new proteins, but only small RNAs, which are very unstable molecules and are degraded during food processing.

The collected information was presented to the CTNBio regulators in 2010, approving its commercial release in 2011, a historic milestone as it was developed entirely by a public entity and was the first GM bean in the world. However, why has it taken about a decade to hit the market since that approval?

“We still didn’t have commercial cultivars, and it hasn’t been possible to develop them before because -here in Brazil- all field trials require authorization and also, each field must be in a certified area,” says Aragao about the Brazilian regulatory system. “And for the data generation rules of a new variety, it must be considered that Brazil has five areas for the bean, and we must carry out trials in at least three zones, of each one of the areas, for two years.”

Due to the cumbersomeness of the certification system, EMBRAPA preferred to wait for the commercial release of line 5.1 and only then to breed it with local varieties and endow them with virus resistance. “After commercial approval, you can sow wherever you want and it’s very difficult to have approval for all areas and zones before commercial approval,” adds Aragao.Related article:  15 years after debuting GMO crops, Colombia’s switch has benefited farmers and environment

After more than 31 field trials analyzing agronomic performance, the first GM cultivars of a Pinto -or Carioca- variety suitable for commercial use had already been obtained in 2015. The average yield of the modified cultivar was almost 20% higher than conventional varieties, and in areas with a high incidence of the virus, the profitability of GM beans was 78% higher.

GM bean field in the city of Río Verde, Goias state, in January 2020. Credit: Francisco Aragao

A fascinating piece of information that should be highlighted is the absolute immunity the modified plants have demonstrated since event 5.1 was obtained. “The losses from BGMV are zero. Every year, since we started experimental planting and until the commercial one, we never observe a single plant with the virus, the plants are totally immune,” says Aragao. A strong contrast with the high level of losses in conventional beans that ranges from 40% to 100% of the plants, and the remaining grain is usually deformed or not suitable for sale.

“With this bean, the idea is to have a reduction in pesticide applications. Instead of doing 10 or even 25 applications, the idea is to only do 3 applications (for other pests). What we did was create something more sustainable and safer for consumers”.

Consumer perception and exports

The rules and regulations were not the only problem to be overcome. Since 2015 it had been time to evaluate the best strategy to bring the new GM Pinto bean, a variety that is planted on more than three million hectares and represents 70% of the beans consumed in the country, to Brazilian tables.

“We started to see how to launch it, because beans are not like soybeans, corn or cotton for us. First, it’s a plant that is there on our plate and is consumed every day. Second, it is much more than a staple food, it has a cultural value,” emphasizes Aragao. Since 2015 they had discussed how to conduct the commercial launch, which did not take place until  the second half of 2020, after the seeds multiplication for the first sale.

What has been the attitude of farmers and consumers? In the case of farmers, apparently a success. “The sale of seed has been 100%. The seed producers didn’t sell more because they didn’t have any more,” says Aragao with a laugh. Regarding consumers, it’s still too early to evaluate it, but considering that supermarkets have been selling many products with GMO labeling for years -because GM corn or soybeans derivatives- Aragao hopes that there will be no rejections with the new bean. “If you go to the street and do a survey asking people if they would eat GMOs, probably 40-60% will say no, but in the supermarket they buy it without any problem,” he emphasizes.

Pinto bean package with the new GM variety. It bears the GM label in a yellow triangle with a letter T inside, and below the text: “Product elaborated from GM beans”. Credit: ChileBio

The fact that the Pinto bean produced in Brazil is destined for exclusive local consumption -unlike other varieties- facilitated its commercial release. “We also have modified black beans [from event 5.1], but for now we decided not to launch to the market, since Brazil exports black beans. For example, we have feijoada that is exported canned, and we don’t want to have problems in other countries,” says Aragao.

Genetic editing and new developments

Aragao and his team continue to work on improvements for this Brazilian bean and are already integrating new gene editing technologies to give it greater drought tolerance, decrease phytates (anti-nutritional components), and bestow resistance to other important bean viruses, such as carlavirus.

He also mentions an interesting work carried out with a GMO approach in collaboration with the Instituto Tecnológico de Monterrey from México in 2016, managing to increase the level of folate (vitamins B9) 150 times, an essential nutrient in fetal development and whose deficiency in pregnant women generates babies with severe congenital problems.

Dr. Francisco Aragao with other GM crops developed under his leadership: A folate-biofortified lettuce (left) and a ricin-free castor bean (right). Credit: ISTOÉ/Embrapa

Other side projects that Aragao and his team are working on include GM lettuce and castor beans. “In lettuce we are working towards virus resistance and an increase in the folate level. We are running field trials and it’s practically ready, but we don’t have all the biosafety data yet. We want to achieve resistance to two very important viruses in lettuce -all over the world – and stack it together with the increase in folate in the same line.”

In castor bean, they seek to eliminate ricin, a highly toxic compound from seeds that makes its use in animal feed unfeasible. “Castor oil plant is a very interesting plant for semi-arid areas, it has a tremendous tolerance to drought and saline soils. The idea is to use a plant like this to obtain not only oil, but also a source of protein for animals,” says Aragao. “The cake that remains after oil extraction is used as fertilizer, but using it as protein for animals would be a much more noble and sustainable purpose.”

Local efforts and science denialism

Until now there has been no opposition from activists and NGOs against the commercial release of the new GM bean. “The anti-GMO groups here in Brazil are fighting against Argentine HB4 wheat, so at least they have forgotten about the bean,” says Aragao. The HB4 wheat he mentions is the first in the world to be approved for commercial release in the neighboring country, but it was conditional on import approval by Brazil, the largest buyer of Argentine wheat.

“Some of the anti-GMO (activists) now claim to be in favor of science for the COVID vaccine. Here we see an example of science denialism. They are deniers depending on the technology, and they don’t consider that some of the modern vaccines are GMOs. To claim that GMOs aren’t safe is simply science denialism. All the scientific data shows that they are safe,” remarks Aragao.

Another important point is that EMBRAPA’s GM bean dismantles the classic narrative against GMOs on the grounds of alleged monopolies or that it’s an exclusive technology of large companies and rich countries. “GM beans are important to show that this technology is not only for big farmers, since we have many small bean farmers in Brazil. Why only for soy, corn and cotton? Why only for large farmers?” asks Aragao.

“It is a technology that can be used for small farmers and to address local problems and crops. Large companies aren’t going to invest in sweet potatoes, cassava, beans or peanuts. They prefer to invest in crops of large areas that are grown in different countries. That is why developing countries have to make an investment in their own problems, and why not, with technologies like this one,” he concludes.

In Brazil, there is hope that this biotechnological solution, fruit of ingenuity and effort of the public sector of Brazil, will be an example to be followed by other Latin American, African and Asian countries. This GM bean approval is a preferrable alternative to walking the European path that has been hindering this technology for more than two decades. Following the Brazilian path shows how to develop local solutions to local problems.

Daniel Norero is a science communications consultant and fellow at the Cornell Alliance for Science. He studied biochemistry at the Catholic University of Chile. Follow him on Twitter @DanielNorero

The GLP featured this article to reflect the diversity of news, opinion and analysis. The viewpoint is the author’s own. The GLP’s goal is to stimulate constructive discourse on challenging science issues.

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CRISPR sows seeds of change in agricultural biotechnology

Since its introduction in 2012, CRISPR-based genetic engineering technology has transformed biotechnology and opened new possibilities in biomedicine. Currently, CRISPR is driving development in yet another domain—agriculture. Although CRISPR has been slower to realize agricultural applications than biotechnology and biomedical applications, it is ready to help us cope with an array of agricultural challenges that include an expanding population, a rapidly warming climate, and a shrinking supply of arable land.

Nearly a decade after Charpentier and Doudna’s landmark study demonstrating that CRISPR systems could be programmed for targeted DNA cleavage in vitro (Jinek et al. Science 2012; 337(6096), 816–821), scientists have started to make good use of CRISPR systems in agricultural biotechnology (agbiotech). In fact, the first genome-edited agricultural product has already hit the market in Japan. This product is a tomato called the Sicilian Rouge High GABA. It was engineered by Sanatech Seed, and it is meant to help consumers reduce their blood pressure. If this product does well, it may encourage other agbiotech companies to ramp up their own CRISPR genome editing programs.

CRISPR has both practical and regulatory advantages over traditional plant breeding and genetic modification methods. Consequently, CRISPR is looking increasingly attractive to agbiotech companies that hope to engineer products that can improve human health and the environment.

“It’s all about genetic variability,” affirms Sam Eathington, PhD, the chief technology officer at Corteva Agriscience, one of the Big Four seed companies. “In some crops, we don’t have as much variability as we’d like. There are times that variability is locked up in parts of the genome that you just can’t unlock easily. Or you bring in a gene for improved disease resistance from a wild species that can intermate, but you bring along a whole bunch of stuff that’s detrimental.” CRISPR can overcome those obstacles, accessing that variability while removing unwanted baggage.

Read the complete article at www.genengnews.com.

Publication date: Thu 12 Aug 2021

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Wineries in California have been under siege for decades. There’s finally hope that grapevines can be saved from bacterial disease

Agostino Petroni | August 12, 2021

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Pierce's disease. Credit: California Department of Food and Agriculture
Pierce’s disease. Credit: California Department of Food and Agriculture

This article or excerpt is included in the GLP’s daily curated selection of ideologically diverse news, opinion and analysis of biotechnology innovation.In 1961, Adam Tolmach planted a five-acre vineyard on land he had inherited from his grandfather in the wine-growing region of Ventura County, California, a few miles east of Santa Barbara. As an undergraduate, Tolmach had studied grape growing and winemaking (areas of study known as viticulture and enology, respectively) and then worked for a couple of years at a winery not far from his grandfather’s land. In 1983, he started producing his own wines, which he sells under the Ojai Vineyard label.

Over the years, Tolmach’s grapevines began to suffer. The plants lost vigor and the leaves dried. It turned out the vineyard was affected by Pierce’s disease, a sickness that had long plagued southern California, but had become more severe in the 1990s after the invasion of the glassy-winged sharpshooter, a large leafhopper insect that feeds on plant fluids and can spread a bacterium known as Xylella fastidiosa, usually just called Xylella (pronounced zy-LEL’-uh). This bacterium has existed in the United States since as far back as the 1880s, and over the years, it has destroyed at least 35,000 acres of the nation’s vineyards.

Adam Tolmach. Credit: Ojai Vinyard

Tolmach witnessed the slow but certain death of his grapevines. By 1995, there were just too many missing plants, he said. So he decided to pull out the infected vineyard. To continue making wine, he bought grapes from other producers. Tolmach became a winemaker with no vineyard of his own.

Every year, American winemakers lose about $56 million worth of vines, while government agencies, nurseries, and the University of California system invest another $48 million in prevention efforts, according to research published in the journal California Agriculture. At least 340 plant species serve as hosts to Xylella, though the bacteria only harm some of them. Across the globe, Xylella has devastated orange trees in Brazil and olive fields in southern Italy, and recently a newly identified species, Xylella taiwanensis, has been infecting pear trees in Taiwan. As of now, there is no permanent solution. Each time a Xylella species has invaded a new region, it has proved impossible to eradicate.

Countries have long fretted about the potential for infected plant imports to spread the bacteria, and more recently, climate change has been identified as an additional threat, pushing the disease vectors’ habitat north, both in Europe and in the U.S. As winters become warmer, experts say, Xylella could enter new territories, upending their regional economies and landscapes.

Yet there might be some hope. After 40 years of crossbreeding European grape varieties with wild grapes, a plant geneticist recently patented five hybrid grapes that appear to be resistant to Pierce’s disease. While scientists caution that it’s not yet clear how long the resistance will endure, wine producers like Tolmach hope that these new grapes will allow their vineyards to flourish once again.

A variety of grape species are indigenous to America, and a recent study suggests that Native Americans might have used them to make alcoholic beverages more than 500 years ago. In North America, native varieties tend to have thick skin and an astringent, peppery, acidic taste that is quite different from the grapes used in most wines.

In the 1500s, Spanish settlers brought Vitis vinifera, the common European grapevine for winemaking, to Florida. Farmers never succeeded in cultivating European grapes in the new territory — after a few years, the plants would just die. Then, in the 1860s, the Los Angeles Vineyard Society led grape-planting efforts in the Santa Ana Valley. By 1883, there were a total of 50 wineries and 10,000 acres of grapevines. Then, just a couple of years later, the grapevines had all died inexplicably.

In 1889, the U.S. Department of Agriculture instructed one of the first formally trained American plant pathologists, Newton Pierce, to figure out what was killing the European grapevines. Pierce studied the disease, eventually speculating that it was caused by a microorganism, but he never identified one. Still, in recognition of his effort, the disease was eventually named after him.

In the 1970s, a University of California, Berkeley entomologist named Alexander Purcell helped solve the mystery. At the time, researchers were beginning to think Pierce’s disease was caused by bacteria but had yet to pin down a culprit. Purcell and his colleagues proved the then-unnamed Xylella was responsible by growing the bacterium from samples taken from plants infected by blue-green sharpshooters, and then directly infecting healthy plants with the lab-grown pathogen. Over time, a more complete picture of disease transmission emerged.

The glassy-winged sharpshooter feeds on the green stems and leaves of grapevine plants, which contain water and dissolved nutrients, Purcell told Undark. If the plant is infected with Xylella, some of the bacteria linger in the insect’s needle-like mouthparts. The next time the glassy-winged sharpshooter feeds upon a grapevine, the insect can transfer the Xylella to the new plant. Inside the plant’s vascular tissues, the bacteria multiply, obstructing the normal flow of water and nutrients and interfering with the plant’s metabolism and physiology — a process that ultimately kills the plant.

In the late 1980s, Purcell mapped swaths of the U.S. and Europe by how conducive they are to disease spread. Knowing that Xylella do not thrive in regions with cold winters, that are far from large bodies of water, and that lack a disease-carrying vector such as the glassy-winged sharpshooter, Purcell drew out maps by hand. He then marked the regions with the right combination of geographic and climatic conditions to allow for Pierce’s disease to spread, noticing a pattern emerge.

At the time, the European Union was not very concerned about Xylella, though Purcell contends that the bacteria had almost certainly arrived in the region. In talks and at conferences, he warned that European countries were facing a great danger. He urged the E.U. to increase its regulations of plant imports. Those warnings went unheeded, Purcell said, and in 2017, Pierce’s disease was first detected on the grapevines of the Spanish island of Mallorca, jeopardizing the future of winemaking there. Today, Xylella is spreading through the Mediterranean region and other parts of Europe — just as Purcell predicted.

The glassy-winged sharpshooter spreads Xylella bacteria when it feeds on the vascular tissues of plants. Credit: Courtesy of University of California, Riverside

Alberto Fereres, a Spanish entomologist and researcher at the Spanish National Research Council, is concerned about the devastating effects of the European outbreaks, including one in southern Italy that has infected and killed 20 million olive trees, more than a third of the region’s population. “[Xylella] is present in many more countries than we indeed thought,” Fereres said, adding that his research group recently discovered that the bacteria have been present in Spain for more than 20 years, but for much of that time it only lived in plants that don’t show symptoms of the disease.

Fereres hopes at least some plants will adapt to the presence of the bacteria and that farmers will be able to control the indigenous European vector, the meadow spittlebug, by tilling the land to kill the bug’s juveniles and placing barriers or nets to separate the insects from susceptible plants.

So far, the U.S. has largely used insecticides to get rid of infected insects. The Temecula Valley in California, for example, experienced a severe outbreak of Pierce’s disease in the late 1990s. Back then, stakeholders managed to defeat the disease in less than two years by introducing specific pesticides into the farming of grapevines.

Matt Daugherty, an entomologist at the University of California, Riverside, studied the resulting decline in Temecula’s glassy-winged sharpshooter population. He said the insect’s numbers remained low until around 2017, when the population exploded for a second time.

“Now the bad news is this,” Purcell said: “After about 18 years, the insect is now resistant to the insecticide.” In entomology, Purcell added, such resistance is common if the same insecticide is used year after year. He and Fereres maintain that pesticides are not a viable long-term solution to the problem. In some countries, this approach has also run up against public opinion. In Italy, for example, consumers have strongly opposed the use of pesticides on olive trees threatened by Xylella.

Rodrigo Almeida, a plant pathologist at the University of California, Berkeley, warns that climate change might worsen the situation: While low winter temperatures in many grape-growing regions have traditionally limited the spread of Pierce’s disease, the past few years have brought warmer winters, allowing Xylella to spread.Follow the latest news and policy debates on agricultural biotech and biomedicine? Subscribe to our newsletter.SIGN UP

“With warming temperatures and warmer winters, you’re going to have sort of more disease where you already have it, and you’re probably going to see the range expand north as well,” Almeida said. Warmer temperatures favor greater survival of the insects and increase the likelihood that an infection will persist through the winter. Almeida added that it’s difficult to predict precisely how much the disease will increase and how it will impact the new territories, but that there is the possibility that the disease will find a home in areas where a dry climate combines with warmer winters.

“We’re expecting things to get worse and worse,” Daugherty said.

Yet, in territories where European grapes die because of Xylella, wild indigenous grape varieties that are not a good fit for winemaking thrive. Those plants bear a unique gene that prevents them from succumbing to the disease, and that specific gene could be a counteroffensive to the bacteria and might well change the future of winemaking.

In 1989, University of California, Davis plant geneticist and viticulturist Andrew Walker inherited grapevine seeds that he was told were produced from crossbreeding two known Vitis species. But as the plants grew, he soon noticed they were behaving weirdly. For one thing, their vines had sprouted fine hairs along the stems. More importantly, the plants proved resistant to Pierce’s disease. Walker decided to investigate. Perhaps, he speculated, the parent plants, which were still flourishing in an abandoned vineyard owned by his university, had accidentally crossbred with the native grapevines that were growing wild nearby.

Indeed, this turned out to be the case. Vitis arizonica grows wild in the southwest U.S. and Mexico, and Walker matched the genetic fingerprint of the male V. arizonica in his own plants. The wild plant carries a dominant gene that passes along Pierce’s disease resistant traits to its offspring.

Sensing that this could lead to breakthrough for new varieties of grapevine, Walker began the slow process of crossbreeding. This technique goes back about 10,000 years and involves selectively breeding plants and animals with desired traits. In this case, Walker wanted to cross disease-resistant V. arizonica with winemaking varieties like cabernet sauvignon.

A grapevine leaf affected by Pierce’s disease. As the plant’s vascular structure is obstructed by bacteria, the flow of water and nutrients is impeded, and the leaves become brown and dry. Credit: Agricultural Research Service/USDA

The first generation’s seedlings all carried the gene for disease resistance. Walker selected the highest quality among them, and when the plants flowered, he crossed them again with various V. vinifera varieties. He did this for four to five generations, reaching a point where 97 percent of the plant’s genome came from V. vinifera and 3 percent came from V. arizonica. It took Walker about 20 years to develop these new plants, five varieties of which have been patented and given out to a few producers, and sold through a handful of nurseries. Tolmach, the winemaker from Ojai, was one of the few lucky ones to receive them.

“I guess what’s shocking to me is that the quality is there — these can be standalone wines by themselves,” said Tolmach. In 2017, he planted about 1,800 plants on 1.2 acres with four of Walker’s varieties, and he recently bottled the 2019 vintages. (These vintages won’t be available until this fall, when they will be priced between $30 and $40 per bottle, which is comparable to his vintages that use traditional grapes.) Tolmach said that his new plants are healthy and thriving with no sign of the disease, and he’s now thinking of planting more on a 10-acre vineyard that he purchased in northern Santa Barbara County.

Matt Kettmann, a California writer and wine critic who has been following Tolmach’s work for years, tasted Tolmach’s wines produced with resistant grape varieties. He said they are unique and interesting wines with characteristics reminiscent of wines of European heritage. He described Tolmach’s 2019 wine using Walker’s paseante noir grape as tasting of “black cherry, mocha, clove, baking spice,” while praising its “smooth texture and rich mouthfeel.” “That one,” said Kettmann, “was really kind of impressive to me.”

Kettmann anticipates that the new wines will be appreciated by connoisseurs, but he wonders how the larger American market will respond. Europeans emphasize the value of terroir — the taste imparted to a wine by a particular region’s soil, topography, and climate. Americans, on the other hand, tend to care more about the variety of the grape, like pinot gris, cabernet sauvignon, or zinfandel — and Walker’s varieties are entirely new.

“Tradition is a huge consideration in choosing wine varieties for winemaking. Can you name any new grape varieties introduced during the last 50 years that are now widely used for wine?” wrote Purcell in an email.

It’s also not clear whether new genotypes of Xylella might evolve to infect the hybrid grapes, Purcell and Fereres wrote to Undark. Currently, only a single gene confers the resistance. For this reason, it might be necessary to incorporate new resistance genes by crossbreeding additional varieties of grapevine, said Purcell.

Still, growers like Tolmach are excited by Walker’s resistant varieties, and some are planting them in areas that have been impacted by Xylella, Walker saidThough Tolmach has made wines with the new grapes exclusively, he suggests many wineries may opt to blend the grapes with other mainstream varieties.

For his part, Walker believes that any skepticism about his grapes’ novelty will fade in the face of climate change. “It is going to force people to reevaluate how we improve grapevines,” he said.

Agostino Petroni is a journalist, author, and a 2021 Pulitzer Reporting Fellow. His work appears in a number of outlets, including National Geographic, BBC, and Atlas Obscura. Find Agostino on Twitter @PetroniAgostino

A version of this article was originally posted at Undark and is reposted here with permission. Undark can be found on Twitter @undarkmag

The GLP featured this article to reflect the diversity of news, opinion and analysis. The viewpoint is the author’s own. The GLP’s goal is to stimulate constructive discourse on challenging science issues.

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Preview(opens in a new tab)Add titleGene editing poised to spark innovation in herbicide- and disease-resistant sugar cane

Gene editing poised to spark innovation in herbicide- and disease-resistant sugar cane

Julie Wurth | CABBI | July 22, 2021

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Credit: Fawakih
Credit: Fawakih

This article or excerpt is included in the GLP’s daily curated selection of ideologically diverse news, opinion and analysis of biotechnology innovation.

Sugarcane is one of the most productive plants on Earth, providing 80 percent of the sugar and 30 percent of the bioethanol produced worldwide. Its size and efficient use of water and light give it tremendous potential for the production of renewable value-added bioproducts and biofuels.

But the highly complex sugarcane genome poses challenges for conventional breeding, requiring more than a decade of trials for the development of an improved cultivar.

Two recently published innovations by University of Florida researchers at the Department of Energy’s Center for Advanced Bioenergy and Bioproducts Innovation (CABBI) demonstrated the first successful precision breeding of sugarcane by using CRISPR/Cas9 genome editing — a far more targeted and efficient way to develop new varieties.

CRISPR/Cas9 allows scientists to introduce precision changes in almost any gene and, depending on the selected approach, to turn the gene off or replace it with a superior version. The latter is technically more challenging and has rarely been reported for crops so far.Follow the latest news and policy debates on agricultural biotech and biomedicine? Subscribe to our newsletter.SIGN UP

“Now we have very effective tools to modify sugarcane into a crop with higher productivity or improved sustainability,” [researcher Fredy] Altpeter said. “It’s important since sugarcane is the ideal crop to fuel the emerging bioeconomy.”

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Bt Cotton adoption in Punjab has resulted in net economic, environmental benefits: Study

Vikas VasudevaCHANDIGARH, JUNE 21, 2021 19:34 ISTUPDATED: JUNE 22, 2021 15:52 IST

Yields have stabilised after its commercialisation, says expert

Amid the perpetual debate surrounding Bt cotton’s positive and negative impacts, a recent study titled — ‘Long-term impact of Bt cotton: An empirical evidence from North India’ — has said its adoption in Punjab in the past over a decade has resulted in net economic and environmental benefits.

Also read: Comment | The flawed spin to India’s cotton story

The research was funded by the Agricultural Extension Division of the Indian Council of Agricultural Research under extramural project “Impact evaluation of integrated pest management technologies”. The study was jointly done by the Punjab Agricultural University at Ludhiana, the Sher-e-Kashmir University of Agricultural Sciences and Technology in Jammu (SKUAST) and the Noida-based Amity University, and has been recently published in the Journal of Cleaner Production Elsevier.

“Since the commercialisation of Bt cotton, there has been reduction in insecticide use by volume and applications, decline in environmental and human health impact associated with insecticide use, more so with the reduction in the use of highly hazardous and riskiest insecticides, and reduction in the expenses associated with insecticide use. Also, cotton yields in the past 13 years have been stable, the only exception being 2015. Yet over the past 13 years, pesticide use has gradually increased in Bt hybrids and reduced in non-Bt varieties, primarily driven by the use of fungicide, which was not applied in cotton in 2003 and 2004.

“Akin to the discovery of synthetic pesticides in the 1940s, which was proclaimed as ‘silver bullet technology’ by entomologists, the complete reliance on Bt cotton without incorporating it into the integrated pest management (IPM) system led to outbreak of whitefly in northern India and pink bollworm in western India in 2015; thus, resistance to Bt cotton is yet to become a significant problem. Compatibility of Bt with IPM is not a given when we have weaker institutional setting with ad hoc IPM system and the contrarian view that Bt cotton has been a failure in India, in this case Punjab, lacks empirical evidence,” professor Rajinder Peshin of SKUAST told The Hindu.

Bt (Bacillus thuringiensis) cotton has been commercially grown in India for the past 19 years. The Genetic Engineering Approval Committee (GEAC) approved the release of Bt cotton for commercial cultivation in 2002 in western and southern parts of the country. In Punjab, Bt cotton was released for cultivation in 2005. Before the release, it was adopted by 72% farmers on 22% of the cotton area. However, a lot of questions have been raised recently on its impact.

“To find out the long-term socio-economic and environmental impacts of Bt cotton cultivation on cleaner production, we revisited cotton growers surveyed in 2003 and 2004 again in 2016-17. Before-after, with-without, and difference-in-differences [with and without sample attrition] within farm comparisons were analysed to find the impact of Bt cotton over time. Our results show that sucking insect pests have replaced bollworms as the key pests.

Decline in insecticide applications

“There has been a steep decline in insecticide applications to control bollworms, the target pest of Bt cotton, by 97%; however, this has been offset by an increase in the insecticide application by 154% to control sucking pests. Moreover, the increase in pesticide use was driven by the use of fungicides, which were not applied in cotton earlier, and increased use of herbicides.

“Our results show overall positive impact of Bt cotton on volume of insecticide active ingredients (a.i.) applied, insecticide applications, use of highly hazardous and riskiest insecticides, and resultant environmental impact of the field use of insecticides on cotton. Yields have stabilised after the commercialisation of Bt cotton,” said Mr. Peshin.


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May 24, 2021“Father of Hybrid Rice” Yuan Longping’s Legacy: An agricultural innovation that helps feed the world

“Father of Hybrid Rice” Yuan Longping’s Legacy: An agricultural innovation that helps feed the world

Rice is a staple food and provides 20% of the daily calorie needs of more than half of the population worldwide. With the looming increase in population projected to reach about 8.5 billion people by 2030, how can we feed the world sustainably?

In 1973, Dr. Yuan Longping successfully cultivated the first high-yielding hybrid rice strain after almost a decade of hybrid rice research. Since then, several varieties of hybrid rice have been developed and deployed to end hunger and improve the livelihoods of smallholder farmers across the world.

“If half of the rice-growing areas in the world are replaced with hybrid rice varieties with a 2 t/ha yield advantage, it is estimated that total global rice production would increase by another 150 million tons annually. This could feed 400‒500 million more people each year. This would truly be a significant contribution to ensure food security and peace all over the world,” writes Dr. Yuan in his Rice Today opinion piece,  Hybrid rice for global food security.

Among the numerous awards and recognitions that he received for this contribution to agriculture and food security, Dr. Yuan was awarded the prestigious World Food Prize in 2004, the foremost international award recognizing individuals who have increased the quality, quantity, or availability of food in the world. Dr. Yuan “discovered a genetic phenomenon in rice and then developed the technologies essential for breeding the first hybrid rice variety ever created.” He shared the recognition with African plant breeder, Dr. Monty Jones.

President emeritus of the World Food Prize and vice-chairman of the Yuan Longping International Rice Development Forum Kenneth M. Quinn said of Dr. Yuan, “Like [Norman] Borlaug, Professor Yuan was incredibly humble, never seeking fame or adulation, rather focused only on hard work and results that could help eradicate poverty and uplift people out of hunger. Professor Yuan, similarly, believed deeply in the power of science as the multiplier of the harvest.”

Most recently, Dr. Yuan worked with his team on a third-generation hybrid rice variety. Reports from late last year cite that this third-generation hybrid rice achieved a yield of 911.7 kg per mu (about 667 square meters) in an experiment in China’s Hunan Province.

“The adoption of agricultural innovations like the hybrid rice technology will help in bringing about rice self-sufficiency in rice-dependent countries,” IRRI Director General Jean Balié said. “Hybrid rice’s yield advantage is instrumental in feeding a growing population with fewer resources. We will be forever grateful for Dr. Yuan Longping’s dedication and hard work on hybrid rice research which paved the way for the development and deployment of several high-performing rice varieties.”

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Is genetically modified corn the answer to fall armyworm? 

ABC Rural / By Megan HughesPosted 3ddays ago

A close up of a caterpillar on a stalk of corn. It's clear the grub has done a lot of damage
Fall armyworm has been detected across the country from North Queensland to Western Australia and even Tasmania.(Supplied: DPIRD)

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  • It’s a tiny caterpillar that’s difficult to detect, but for more than a year it’s been having a massive impact on crops in Australia, especially corn. 

Key points:

  • Fall armyworm is causing damage to corn crops around Australia 
  • Farmers are asking whether genetically modified corn could help
  • The Maize Association says it will need whole-of-industry support before GM corn can be introduced  

Fall armyworm (FAW) has infiltrated six states and territories and is so hard to control farmers are whispering about a method that’s been off the table for almost two decades — genetically modified (GM) corn.

Maize Association of Australia chairman Stephen Wilson said questions were being raised about whether GM corn could manage the armyworm incursion.

“Anecdotally, I am hearing from the field farmers saying we need GM to help us control the insect,” he said. 

“It’s a major discussion point for the industry as a whole because for the last three decades we, as an industry, as the Maize Association, have been working uniformly to say we do not need GM in Australia.” 

Lessons from the US 

Since arriving in Australia in February 2020, fall armyworm has been detected in Queensland, the Northern Territory, Western Australia, New South Wales, Victoria and, most recently, in Tasmania. 

Fall armyworm is native to the United States, where it has devastated multiple agricultural crops, but growers there have different tools to fight it. 

Fall armyworm on corn plants
Fall armyworm outbreaks are contained by insecticide use and GM crops in the United States.(Supplied: Queensland Department of Agriculture and Fisheries)

North Carolina State University professor and extension specialist Dr Dominic Reisig said in their industry, corn was genetically modified to produce insecticidal proteins that naturally occurred in a bacteria found in soil. It is known as BT corn.

Dr Reisig said while it was not specifically designed to treat FAW it had had an impact. 

“It was first commercially planted in 1996 but that particular crop that was planted did not control fall armyworm,” he said.

“So it wasn’t until different BT toxins were introduced that we really started to see fall armyworm control. 

“But because it’s a sporadic outbreak pest throughout the US it wasn’t like a huge, earth-shattering moment when we were able to control fall armyworm.” 

Are GMO crops the silver bullet? 

According to Dr Reisig, treating FAW across ag industries was a multi-pronged approach with insecticides and a GM crop. 

He said in corn the pest could infest a crop in different stages of its development. 

“Once it gets into the whirl it’s very difficult to control,” he said. 

“But the good thing is when it attacks in those (earlier) stages it’s not that damaging to yield — so the corn looks really bad but it usually pops out of it and it’s not a problem. 

“If fall armyworm attacks later in the season when maize has an ear, then it’s a problem. 

“Once it’s inside that ear you can’t control it and then it’s a really damaging pest in terms of yield and it’s really difficult to control with insecticides so BT (corn) is the way to go.”

He said insecticides were able to control the pest in other crops like soya beans or vegetables because the plants were structured differently.

Weighing up the losses 

Australia only grows three GM crops — cotton, safflower and canola. 

A sea of yellow flowers under a blue sky as the canola crop is in full bloom.
Canola is one of thee genetically modified crops in Australia.(Supplied: Riverine Plains Inc)

Corn has remained GM-free and, as a consequence, the industry has been able to access different markets including Japan and Korea. 

“End users such as snack food and cornflake breakfast cereal manufacturers have told us the whole time they do not want GM in their raw materials,” Mr Wilson said. 

“It would impact on both the export market and also on all the domestic markets — everything from dairy cows utilising the maize as grain or silage right through to beef cattle and right through to human consumption. 

“It’s a major, major, major impact that would need to be agreed to by all sectors of the industry.” 

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A person opens a corn's covering to check if it's ripe.
Australia has been able to access multiple international markets as the corn grown here is GM free.(Pexels: Frank Meriño)

He said any trial would be complicated.

“You have all the regulatory issues of actually bringing germplasm into the country, you have the quarantine issues of having the facilities that could handle the GM product, then you’ve got the issues of field testing,” he said. 

“It would be a long, drawn-out process and we’d have to consider the impact on the industry as a whole because it’s very hard, if not impossible, to have part-GM, part-non-GM. 

“It’s a very expensive process and it makes the non-GM corn being in the minority a very expensive product that people have to pay a premium for.” 

In a statement, a spokesperson from the Federal Department of Agriculture, Water and the Environment said genetically modified maize seeds may only be imported into Australia under an import permit issued by the department, but that no applications had been made. 

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ToBRFV resistant tomatoes

In 2020, Enza Zaden announced the discovery of the tomato brown rugose fruit virus (ToBRFV) High Resistance gene, a complete solution for ToBRFV. Since the announcement, we’ve worked hard with resistant trials material achieving excellent results. “We see no symptoms at all in the plants, while the disease pressure is very high,” says Oscar Lara, Senior Tomato Product Specialist, about the first trials in Mexico.

No symptoms at all
At the Enza Zaden trial location in Mexico, the high resistance (HR) varieties are placed next to susceptible ones. There you can clearly see the difference. The susceptible tomato varieties show different foliage disorders such as a yellow mosaic pattern. The affected plants also stay behind in growth.

“You can clearly see how well our high resistant varieties withstand ToBRFV,” says Oscar Lara. “In comparison to the plants of susceptible varieties, the resistant ones look very healthy with a dark green colour, show no symptoms at all and have good growth. All our trialled HR tomato varieties do not show any symptoms at all.”

Exciting news
Enza Zaden is running parallel tests in different countries with varieties with high resistance to ToBRFV. “Our trials in Europe, North America, and the Middle East show that we have qualitatively good tomato cultivars with a confirmed high resistance level,” says Kees Könst, Crop research Director. “This is exciting news for all parties involved in the tomato growing industry. We know there is a lot at stake for our customers, so we continue to work hard to make HR varieties available for the market. We expect to have these ready in the coming years,” says Könst.

High performing and high resistance
Enza Zaden has a long history in breeding tomatoes. “We have an extended range of tomato varieties, from large beef to tasty vine tomatoes (truss tomatoes) and from baby plum tomatoes to pink varieties for the Asian market. This basis of high performing varieties combined with the gene we discovered, will enable us to deliver the high performing varieties with high resistance to ToBRFV.”

Why is a high resistance level so critical?
“With an intermediate resistance (IR) level, the virus propagation is delayed but ToBRFV can still enter tomato plants – plants that may eventually show symptoms,” says Könst. “With a high resistance level, plants and fruits do not host the virus at all. This means they won’t be a source for spreading the virus and that the detection test will come back negative. Growing a variety with high resistance can be the difference between making a profit or losing the crop.”For more information Enza Zadeninfo@enzazaden.com
www.enzazaden.com

Publication date: Tue 13 Apr 2021

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JULY 20, 2020

Returning to farming’s roots in the battle against the ‘billion-dollar beetle’

by University of Arizona

Returning to farming's roots in the battle against the 'billion-dollar beetle'
Western corn rootworm larvae can devour the tips of corn roots, robbing the plants of nutrients and making them susceptible to falling over. Credit: Cyril Hertz, Lingfei Hu and Matthias Erb, University of Bern, Switzerland

Nicknamed the “billion-dollar beetle” for its enormous economic costs to growers in the United States each year, the western corn rootworm is one of the most devastating pests farmers face.https://3777ec3032f89ac36b1a5fe5c7568749.safeframe.googlesyndication.com/safeframe/1-0-37/html/container.html

“They are quite insidious. They’re in the soil gnawing away at the roots and cutting off the terminal ends of the roots—the lifeblood of corn,” said Bruce Tabashnik, Regents Professor and head of the University of Arizona Department of Entomology. “And if they’re damaging enough, the corn plants actually fall over.”

Genetically modified crops have been an important tool in the battle against pests such as these, increasing yields while reducing farmers’ reliance on broad-spectrum insecticides that can be harmful to people and the environment.

Corn was genetically engineered to produce proteins from the bacterium Bacillus thuringiensis, or Bt, that kill rootworm larvae but are not toxic to humans or wildlife. The technology was introduced in 2003 and has helped keep the corn rootworm at bay, but the pest has begun to evolve resistance.

“So, now the efficacy of this technology is threatened and if farmers were to lose Bt corn, the western corn rootworm would become a billion-dollar pest again,” said Yves Carrière, a professor of entomology in the College of Agriculture and Life Sciences.

Crop Rotation in Mitigating Pest Resistance

Carrière is lead author of a study to be published in PNAS that evaluated the effectiveness of crop rotation in mitigating the damage caused by resistant corn rootworms. Tabashnik and colleagues from North Carolina State University, the University of California-Davis, McGill University and Stockholm University coauthored the study.

Crop rotation, the practice of growing different crops in the same field across seasons, has long been used for pest control. In 2016, the U.S. Environmental Protection Agency mandated crop rotation as a primary means of reducing the damage to Bt corn fields caused by resistant corn rootworms, but there have been limited scientific studies to support the efficacy of this tactic.https://googleads.g.doubleclick.net/pagead/ads?client=ca-pub-0536483524803400&output=html&h=280&slotname=5350699939&adk=2265749427&adf=625945176&w=750&fwrn=4&fwrnh=100&lmt=1595996918&rafmt=1&psa=1&guci=2.2.0.0.2.2.0.0&format=750×280&url=https%3A%2F%2Fphys.org%2Fnews%2F2020-07-farming-roots-billion-dollar-beetle.html&flash=0&fwr=0&rpe=1&resp_fmts=3&wgl=1&dt=1595996918602&bpp=11&bdt=88&idt=147&shv=r20200727&cbv=r20190131&ptt=9&saldr=aa&abxe=1&cookie=ID%3Dfd49ee1f356c7aad-2230268791c20026%3AT%3D1595996908%3AS%3DALNI_MZ__AIkhsEMsw1AjrlZUCXlh_wvFw&correlator=2622896222429&frm=20&pv=2&ga_vid=683244895.1595996911&ga_sid=1595996919&ga_hid=1573871060&ga_fc=0&iag=0&icsg=2271232&dssz=26&mdo=0&mso=0&u_tz=-300&u_his=2&u_java=0&u_h=1080&u_w=1920&u_ah=1040&u_aw=1920&u_cd=24&u_nplug=3&u_nmime=4&adx=447&ady=2184&biw=1903&bih=969&scr_x=0&scr_y=0&oid=3&pvsid=1003068873479674&pem=0&rx=0&eae=0&fc=896&brdim=0%2C0%2C0%2C0%2C1920%2C0%2C1920%2C1040%2C1920%2C969&vis=1&rsz=%7C%7CpeEbr%7C&abl=CS&pfx=0&fu=8320&bc=31&ifi=1&uci=a!1&btvi=1&fsb=1&xpc=7ptrOeJu1R&p=https%3A//phys.org&dtd=154

Carrière and his team rigorously tested this approach by analyzing six years of field data from 25 crop reporting districts in Illinois, Iowa and Minnesota—three states facing some of the most severe rootworm damage to Bt cornfields.

The results show that rotation works. By cycling different types of Bt corn and rotating corn with other crops, farmers greatly reduced rootworm damage.

Most notably, crop rotation was effective even in areas of Illinois and Iowa where rootworm resistance to corn and soybean rotation had been previously reported.

According to the study, crop rotation provides several other benefits as well, including increased yield, reductions in fertilizer use and better pest control across the board.

“Farmers have to diversify their Bt crops and rotate,” Carrière said. “Diversify the landscape and the use of pest control methods. No one technology is the silver bullet.”

Returning to farming's roots in the battle against the 'billion-dollar beetle'
Western corn rootworm beetle on corn tassels. Credit: Joseph L. Spencer, Illinois Natural History Survey, University of Illinois at Urbana-Champaign

A Multipronged Approach

Tabashnik relates the research back to UArizona’s work with the pink bollworm, in which researchers spearheaded a management program to suppress the pink bollworm’s resistance to Bt cotton.

“The key to eradicating pink bollworm in the U.S. was integrating Bt cotton with other control tactics,” Tabashnik said. “We succeeded, whereas this voracious invasive pest rapidly evolved resistance to Bt cotton in India, where the genetically engineered crop was used alone.”

In collaboration with cotton growers, UArizona scientists sustained the efficacy of Bt cotton against pink bollworm by establishing the “refuge strategy,” in which non-Bt crops are planted near Bt crops to allow survival of susceptible insects. The strategy has become the primary approach used worldwide to delay the adaptation of insect pests to genetically engineered crops.

Although farmers have used refuges to thwart the rootworm’s resistance to Bt corn, this strategy alone has proven insufficient against the pest.

“During the last decade, we have learned that refuges are often not sufficient to delay resistance in pests like the corn rootworm,” Carrière said. “It would be wise to diversify management tactics before such pests evolve resistance. This approach, called integrated pest management, is vital for preserving the benefits of biotechnology.”

Returning to Agricultural Roots

In many ways, the study reaffirms traditional agricultural knowledge.

“People have been rotating crops since the dawn of farming. The new agricultural technology we develop can only be sustained if we put it in the context of things we’ve known for thousands of years,” Tabashnik said. “If we just put it out there and forget what we’ve learned in terms of rotating crops, it won’t last.”

The authors emphasize that increasing crop rotation is essential for sustaining the economic and environmental benefits provided by rootworm-active Bt corn. During the six years of the study, the average percentage of corn rotated to other crops per state ranged from about 55-75%.

“This is one of the most important applications of Bt crops in the United States,” Carrière said. “If we lose this technology and we start using soil insecticides again, it’s going to have a big negative environmental impact.”


Explore furtherScientists offer recommendations for delaying resistance to Bt corn in western corn rootworm


More information: Crop rotation mitigates impacts of corn rootworm resistance to transgenic Bt corn, PNAS (2020). DOI: 10.1073/pnas.2003604117Journal information:Proceedings of the National Academy of SciencesProvided by University of Arizona

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CGIAR – Gender and breeding intiatives
http://www.rtb.cgiar.org/gender-breeding-initiative/news-and-opinions/news/plant-breeders-could-let-women-farmers-guide-them/

Plant breeders produce new varieties for their customers: farmers. To predict what kinds of new varieties are likely to offer significant benefits to farmers, breeders may turn to their customers to evaluate which characteristics might make a new variety more acceptable. A comprehensive review of many such evaluations suggests that if breeders were to pay more attention to what women need, it could increase the usefulness of new varieties in many ways.

[Gender and Farmer Preferences for Varietal Traits: Evidence and Issues for Crop Improvement], published in Plant Breeding Reviews, came out of a workshop of the Gender and Breeding Initiative, led by the CGIAR Research Program on Roots, Tubers and Bananas (RTB). The authors scanned the published literature looking for research that addressed plant breeding, seed selection, trait evaluation and similar ideas and that specifically reported data from women about their varietal preferences. The paper describes their analysis.

Although 39 papers met the criteria, the authors say that none of them focused on gender differences for trait preferences as a primary objective. Women evaluated traits and varieties, but understanding their preferences was never the primary reason for any of the studies. The studies covered a wide variety of crops, countries and agricultural production and food systems. Despite the high diversity and specificity of these cases, the authors identified some trends and patterns.

Security versus productivity

Women and men sometimes have diametrically opposed views about what matters in a plant variety. Women mention traits related to their family’s food security, such as earliness, multiple harvests and pest and disease resistance, more often than men. Men, by contrast, mention varieties with market appeal — high yields, low labor requirements — more often than women.

“Women preferred traits conferring stability or the capacity to produce under stressful conditions,” said Jacqueline Ashby, one of the study authors and Senior Advisor on Gender Research at the CGIAR System Office at the time of the research.

There are differences after the harvest too. Women are more likely to be concerned about traits such as ease of processing and lower processing losses or medicinal properties, reflecting their concern with food quality, while men focus on storage life and marketability.

“Women tend to be responsible for food preparation, and thus have more detailed knowledge about what a good variety should bring to the table,” said Eva Weltzien of the University of Wisconsin and another of the paper’s authors. “If women cannot prepare more food from grain produced by a higher yielding variety, because losses during food preparation are higher than the yield advantages from the new variety, they will not adopt the new variety and will discourage the men from doing so.”

Women are responsible for ensuring that their family is well-fed, and that influences their preferences. In Ethiopia, for example, women say that they are the ones who have to maintain early and drought-tolerant sorghum varieties because “they are the first to hear a starving child cry”.

Same crop, different needs

Many crops are grown by women and men, albeit under different circumstances and sometimes with diverse goals. Very often, women prefer traits that will deliver an assured harvest from the poorer conditions of their plots. In West Africa, the fields on which women grow sorghum are low in fertility because they are allocated those fields at the end of the rotation and they do not have access to manure. They prefer early and tall sorghum varieties, which make the most of poor conditions.

This example, and several others, show that, as the authors note, “even within the same agro‐ecology and village, women and men may be cultivating the same crop under contrasting conditions and thus will have different trait preferences”.

Women tend to value characteristics of crop varieties differently from men when they have different roles and responsibilities during the crop production cycle. For example, when women are primarily responsible for weeding, harvesting or threshing, they will appreciate variety traits that reduce weeding and their workload.

It is also common that women use specific parts of plants that men are less interested in, and ignoring their preferences can block the uptake of an otherwise better variety. In Ethiopia, for example, women objected to more productive short-strawed sorghum varieties partly because they would increase their work, but also because they would reduce the income women earn by selling the sorghum stalks as fuel.

Let women decide

Some crops are seen as “women’s crops,” among them groundnut and Bambara groundnut in West Africa, finger millet in East Africa and traditional vegetables across Africa and Asia. The literature contained no research on gendered trait preferences for these women’s crops which, the authors note, “warrants further research”.

“In fact,” said Jacqueline Ashby, “the idea that some crops are ‘women’s crops’ is questionable. More to the point, whenever women grow any crop for home consumption using rudimentary technology, their opinions about what would improve the crop have been largely ignored by modern breeding.”

GBI and the Excellence in Breeding CGIAR platform have already teamed up to pilot a more systematic approach to ensuring that women’s trait preferences are included in the product profiles that guide the work of plant breeders.

Should the aim be to produce separate varieties for women and men? Probably not.

“It is costly and difficult to develop new varieties,” Eva Weltzien explained. “In most cases it will be better to combine the traits that women and men prefer. For example, there may be no real yield disadvantage for taller sorghum plants.”

Better, Weltzien said, to ensure that women’s preferences are being met. In Ethiopia, a new sorghum variety that is tall and high-yielding improves the likelihood that the improved variety might be adopted, because women and men will want it.


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