Conserving biodiversity: Biocontrol for sustainable agriculture.


May 22, 2023

Laura Hollis

Conserving biodiversity: biocontrol for sustainable agriculture

Can biocontrol help protect biodiversity? Biodiversity refers to all the living things on Earth, including how they interact with each other. A rich biodiversity means a healthy planet. 

A bee on tomato flowers
A bee on flowers of tomato crop. Image: Ajcespedes from Getty Images

However, biodiversity is in decline. The IPBES identified the main contributors to biodiversity loss as the changing use of the sea and land, direct exploitation of organisms, climate change, pollution and invasive species

PlantwisePlus is working to ensure the agricultural sector is part of a healthy landscape with clean water and air and healthy soils, where biodiversity is protected through sustainable approaches to crop pest and disease management.

Pests and diseases constantly threaten farmers’ crops. As a result, pesticides are often the first option when faced with an outbreak. The excessive and misuse of harmful chemicals is particularly damaging to biodiversity. As well as killing off target pests, chemicals also harm beneficial insects such as pollinators and natural enemies. 

PlantwisePlus recognises the urgent need to increase the uptake of lower-risk plant protection. As such, the programme promotes the use of low-risk plant protection solutions such as biological control (biocontrol).

Biocontrol uses living organisms such as natural enemies, predators, parasites or disease-causing organisms to reduce pest populations. Biocontrol is a sustainable and environmentally friendly alternative to chemical pesticides that is also economically efficient, as once natural enemies are established, they provide ongoing control without further cost or intervention.

There are three main types of biocontrol.

Classical biocontrol

Papaya mealybug on papaya fruit
Papaya mealybug on papaya fruit. Image: CABI

Classical biocontrol uses host-specific natural enemies from the pests’ region of origin to control the introduced non-native species. It is primarily used to control invasive species.

In Kenya, PlantwisePlus and partners are working to implement a classical biological control strategy to manage papaya mealybug (Paracoccus marginatus). The invasive pest has been devastating papaya crops in Kenya. A CABI study in 2019 found it caused an estimated 57% yield losses across five counties.

PlantwisePlus has been testing the efficacy of the parasitoid wasp, Acerophagus papayae, as a biological control agent. A parasitoid lives on or inside a host and always kills the host. In contrast, a parasite is an organism that lives in or on a host but does not kill the host.

The parasitoid wasp is native to the Americas and after host range testing in quarantine, researchers released A. papayae in the coastal counties of Mombasa, Kwale, and Kilifi in December 2021. The parasitoid is now established at these pilot sites and controlling the pest.

Find out more about the classical biocontrol strategy to control papaya mealybug.

Augmentative biocontrol

This form of biocontrol involves the mass production and periodic release of large numbers of biocontrol agents to control a pest. 

Fall armyworm on maize
Fall armyworm on maize. Image: CABI

PlantwisePlus has been working with partners in Pakistan to pilot mass production facilities for another parasitic belonging to the genus Trichogramma. Wasps belonging to this genus are commonly sold commercially worldwide, for augmentative biological control of various lepidopteran pests in agriculture and horticulture.

Conservation biocontrol

This form of biocontrol manages pests through the modification of the environment or existing practices to protect and enhance populations of specific natural enemies or other organisms.

CABI scientist Léna Durocher-Granger has been researching the biocontrol of fall armyworm (FAW) in Zambia. The team has identified 15 naturally occurring parasitoid species.

Maize farmers trialing intercropping with nectariferous plants
Maize farmers trialing intercropping with nectariferous plants © Léna Durocher-Granger

Studies have shown that these parasitoids attack up to 45% of the FAW eggs and larvae during the crop cycle. Intercropping maize with nectar-producing plants can help to increase the populations of these beneficial insects. These plants provide food and shelter for the insects, which helps them to survive and reproduce. As a result, there are more insects available to control the FAW population.  

Find out more about conservation biocontrol in Zambia.

CABI Bioprotection Portal

The CABI Bioprotection Portal is an open-access tool that enables users to discover information about registered biocontrol and biopesticide products around the world. Available online and offline, the CABI Bioprotection Portal helps growers and agricultural advisors to identify, source and correctly apply biocontrol and biopesticide products against problematic pests in their crops. The portal is accessible online and offline via smartphones, tablets and desktops.

Visit the CABI Bioprotection Portal

biocontrol, biodiversity, plant health

Agriculture and International Development, Crop health

Invading insects are transforming Antarctic soils



May 10, 2023

by British Antarctic Survey The midge is originally a native of South Georgia before arriving in Signy. Credit: Pete Bucktrout – BAS

A tiny flightless midge that has colonized Antarctica’s Signy Island is driving fundamental changes to the island’s soil ecosystem.

https://58fd2258f1b862b1918712b0b74c5a24.safeframe.googlesyndication.com/safeframe/1-0-40/html/container.html

Research by experts at the British Antarctic Survey (BAS) in collaboration with the University of Birmingham has revealed that a non-native midge species is significantly increasing rates of plant decomposition, resulting in three to five-fold increases in soil nitrate levels compared to sites where only native invertebrates occur.

The study, published in the journal Soil Biology and Biochemistry, was part of a Ph.D. project completed by Dr. Jesamine Bartlett jointly between Birmingham and BAS, and outlines how the midge, Eretmoptera murphyi, is altering soil ecosystems on the island. The insect is a decomposer, feeding on dead organic matter across the island which releases large amounts of nutrients into the soil.

Dr. Bartlett, lead author of the study, says, “Antarctic soils are very nutrient limited systems because decomposition rates are so slow. The nutrients are there, but it has taken this invasive midge to unlock them on Signy Island. It is an ‘ecosystem engineer’ in a similar way to earthworms in temperate soil systems.”

Eretmoptera murphyi, is a native of South Georgia—an island in the sub-Antarctic region. It was introduced to Signy Island by accident during a botany experiment in the 1960s, although its proliferation only became apparent during the 1980s. Prior to this, the only terrestrial sites on Signy with high nutrient levels were those associated with marine species coming ashore, for example penguin colonies and seal wallows.

The level of nitrates measured in soil colonized by Eretmoptera was comparable to that found close to seal wallows, despite the midge being only a few millimeters in size. This is because population densities of midge larvae can reach in excess of 20,000 individuals per m2 at some sites.

Spread by humans, mostly by hitching a ride on the soles of boots of researchers and tourists, the midge has gradually expanded the area it has colonized on the island. It can even survive in sea water for periods of time, leading to conjecture that it could eventually reach other islands.

Professor Peter Convey, a terrestrial ecologist at BAS, says, “A particular feature of the Antarctic is that it has had very few invading species so far and protecting this ecosystem is a very high priority. While at some level, there’s plenty of awareness of the implications of invading species, this research really highlights how the tiniest of animals can still have a hugely significant impact.”

The hostile Antarctic environment is a huge barrier to these invading species with very low temperatures, moisture, and nutrient availability. Alongside rising temperatures in the region, the nutrients released by the midges will start to allow more of these invaders.

Dr. Scott Hayward, an ecologist at the University of Birmingham and co-author, says, “The activity of the midges on Signy, in combination with climate change, potentially ‘opens the door’ for other species to become established which can further accelerate climate change. The midge has the capacity to survive in many Antarctic locations, so monitoring the spread and impacts on Signy is vital for our understanding of other Antarctic ecosystems.”

More information: Jesamine C. Bartlett et al, Ecological consequences of a single introduced species to the Antarctic: terrestrial impacts of the invasive midge Eretmoptera murphyi on Signy Island, Soil Biology and Biochemistry (2023). DOI: 10.1016/j.soilbio.2023.108965

Provided by British Antarctic Survey


Explore further

When ‘alien’ insects attack Antarctica


USA: Reducing Fusarium Head Blight in Winter Barley


USA: Reducing Fusarium Head Blight in Winter Barley

USDA Agricultural Research Service sent this bulletin at 05/15/2023 10:10 AM EDT

View as a webpage ARS News Service ARS News Service Timing Matters When Reducing Fusarium Head Blight in Winter Barley For media inquiries contact: Jessica Ryan, (301) 892-0085
May 15, 2023 When Fusarium head blight (FHB) threatens winter barley, the best time to apply a fungicide is about six days after full barley head emergence, according to a recent study published in Plant Disease. FHB, also known as scab, is a fungal disease that attacks small grains, discoloring the heads and contaminating the grain with the mycotoxin deoxynivalenol (DON), a toxic compound also known as vomitoxin. For barley, the most common grain used to make malt for beer and spirits, even a small amount of DON can cause crops to be rejected by purchasers. The disease in malted barley kernels may lead to gushing, or the rapid and uncontrolled foaming of beer, making the crop unusable for beer production. In a four-year study, researchers with the U.S. Department of Agriculture (USDA)’s Agricultural Research Service (ARS) and the University of Minnesota assessed three different fungicides for FHB reduction. The researchers evaluated the amount of DON present in mature winter barley heads following a fungicide application at one of three growth stages — half heading, full heading, and six days after full barley head emergence.  A stalk of healthy barley next to infected barley Healthy resistant barley (right) and susceptible barley shows symptoms of Fusarium head blight (left). (Photo by Brian Steffenson, University of Minnesota)  “The latest timing of fungicide application reduced DON significantly more than the early timing for all three fungicides tested in the study,”said Christina Cowger, small grains pathologist at ARS’s Plant Science Research Unit in Raleigh, North Carolina. “Applying fungicide before all heads were emerged did not significantly reduce DON in winter barley as compared to not spraying at all. If scab is threatening, growers should wait about six days after barley heads have all appeared before applying fungicide.” According to Cowger, eastern U.S. barley growers have two main tools for FHB management —plant moderately resistant varieties and apply a fungicide. By understanding the best timing for fungicide to minimize FHB, growers can manage high-FHB epidemic years and maximize profits from malting barley. FHB is one of the factors limiting the global production of barley since it can result in yield loss and economic damage. According to the American Phytopathological Society, the disease has cost U.S. wheat and barley farmers more than $3 billion since 1990. “Year in and year out, FHB is the disease that most threatens profitable wheat and barley production in the U.S.,” Cowger said. “Knowing how to get the most out of our FHB management tools is key to small grain profitability.” The Agricultural Research Service is the U.S. Department of Agriculture’s chief scientific in-house research agency. Daily, ARS focuses on solutions to agricultural problems affecting America. Each dollar invested in U.S. agricultural research results in $20 of economic impact. Interested in reading more about ARS research? Visit our news archive U.S. DEPARTMENT OF AGRICULTURE
Agricultural Research Service

France: Enhancing biocontrol | Global Plant Protection News


Science16 May 2023 12:36 am AEST

https://4276c3b3807f224c7c6bf0fd7e7334cf.safeframe.googlesyndication.com/safeframe/1-0-40/html/container.html

INRAE – National Research Institute for Agriculture, Food and Environment

The Egyptian cotton leafworm (Spodoptera littoralis) is a pest species in France. It is found throughout the Mediterranean Basin as well as in Africa and the Middle East. Moth larvae are extremely polyphagous[1] and cause damage to diverse crop species (e.g., corn, legumes, cotton, tomatoes, peppers). As part of broader efforts to reduce pesticide levels, we must develop effective biocontrol methods. Such strategies often rely on disrupting reproduction and trapping moths using, most commonly, sex pheromones. However, pheromone synthesis is an expensive process, and it thus remains important to have other control strategies on hand. To this end, we need to improve our understanding of olfactory receptors in this moth.

In 2019, these research collaborators identified OR5, an olfactory receptor in the Egyptian cotton leafworm that recognises the main compound in the female sex pheromone blend. In this new study, the scientists explored the receptor’s evolutionary trajectory within Spodoptera to better characterise its functionality and specificity. They used a combined approach in which they resurrected ancestral receptors in the laboratory, with the help of computer analysis, and they modelled the 3D structure of the receptors. They were thus able to determine that OR5 appeared around 7 million years ago. The researchers also employed site-directed mutagenesis[2] to explore OR5’s genetic fine-tuning, which allowed them to identify the eight amino acids (AAs) behind the receptor’s high degree of specificity. This finding is particularly unexpected, given that past research on receptor evolution has suggested just one or two AA substitutions suffice to change the functionality of ecologically important receptors.

We must clarify how olfactory receptors emerge and acquire specificity over evolutionary time if we wish to anticipate the development of resistance to pheromone-based plant protection products. This research advances the above goal and, additionally, clarifies the function of OR5, a highly specific receptor that is essential in the reproduction of two Spodoptera species—the Egyptian cotton leafworm and the tobacco cutworm (S. litura). The latter occurs mostly in Asia and is also polyphagous. The discoveries detailed above will help spur the development of new biocontrol strategies that rely on (1) agonist molecules, which occupy receptors to the exclusion of the key pheromone compound, or (2) antagonist molecules, which block the receptor from being activated by the key pheromone compound.

This study arose from a collaboration between the Institute of Ecology and Environmental Sciences of Paris (iEES Paris; under the aegis of INRAE, Sorbonne University, CNRS, IRD, UPEC, and Paris Cité University) and the Chinese National Institute of Plant Protection. It was the fruit of the BiPi International Associated Laboratory.


[1]Polyphagous organisms feed on many different species

[2]Site-directed mutagenesis is a technique that introduces one or more precise mutations into a gene to study the functional impacts on the encoded protein.

/Public Release. This material from the originating organization/author(s) might be of the point-in-time nature, and edited for clarity, style and length. Mirage.News does not take institutional positions or sides, and all views, positions, and conclusions expressed herein are solely those of the author(s).View in full here.

Tags:3D, Africa, Asia, chinese, collaboration, Egypt, France, international, Mediterranean, Middle East, mutations, Paris, protection, reproduction, Scientists, university

The growing urgency of fungal disease in crops


Skip to main content

Advertisement

Nature

More political and public awareness of the plight of the world’s crops when it comes to fungal disease is crucial to stave off a major threat to global food security.

Facebook Email

A dark cloud of dust from smut surrounds a machine harvesting crops on a sunny day
Clouds of dust caused by a fungus engulf a crop field. Credit: Darren Hauck/Reuters

In October 2022, the World Health Organization (WHO) published its first list of fungal pathogens that infect humans, and warned that certain increasingly abundant disease-causing fungal strains have acquired resistance to known antifungals1. Even though more than 1.5 million people die each year from fungal diseases, the WHO’s list is the first global effort to systematically prioritize surveillance, research and development, and public-health interventions for fungal pathogens.

Yet fungi pose another major threat to human health — one that has received even less attention than infections in people.

Hundreds of fungal diseases affect the 168 crops listed as important in human nutrition by the Food and Agricultural Organization (FAO) of the United Nations. Despite widespread spraying of fungicides and the planting of cultivars bred to be more disease resilient, growers worldwide lose between 10% and 23% of their crops to fungal disease every year, and another 10–20% post-harvest2. In fact, the five most important calorie crops — rice, wheat, maize (corn), soya beans and potatoes — can be affected by rice blast fungus, wheat stem rust, corn smut, soybean rust and potato late blight disease (caused by a water mould oomycete), respectively. And losses from these fungi equate to enough food to provide some 600 million to 4,000 million people with 2,000 calories every day for one year3. Such losses are likely to increase in a warming world4,5.

Much more awareness of the plight of the world’s crops as a result of fungal disease is needed, as is more government and private- sector investment in crop fungal research.

Adaptive potential unleashed

In a 2019 list of 137 pests and pathogens (ranked according to impact), fungi dominate the first to sixth places for diseases affecting each of the world’s 5 most important calorie crops6. Wheat, for example, is grown over more land area than any other crop, with production yielding around 18% of all the calories consumed globally each year. Despite mitigation practices, current crop losses worldwide from infections by the Septoria tritici blotch disease-causing fungus Zymoseptoria tritici, the main wheat pathogen in temperate areas, range from 5% to 50%7. Losses caused by the wheat stem rust fungus Puccinia graminis, which frequents more tropical climates, range from 10% to 70% of the harvest3. Commodity crops, such as bananas and coffee, which in many countries generate revenue that is used to purchase calorie crops, are also vulnerable to fungal diseases.Bacterial defence repurposed to fight blight

Fungi are hugely effective pathogens. They produce massive amounts of spores. The spores of some species can persist in soil and remain viable for up to 40 years. In other species, airborne spores can disperse over distances ranging from a few metres to hundreds or even thousands of kilometres. Wheat stem rust, for example, produces airborne spores that can travel between continents8, although many other fungi produce prolific numbers of spores more locally, promoting disease spread within and between adjacent fields.

Fungi also exhibit a phenomenal degree of genetic variation and plasticity9. Over the past decade or so, genome-wide studies have revealed extensive genetic diversity between and within species of fungi. Although some fungal pathogens undergo frequent sexual recombination, genetic variation can be generated through other processes, too. These include mutational changes conferred by transposable elements (DNA sequences that can change their position in the genome), mitotic (asexual) recombination and the horizontal transfer of genetic material — in some cases, between fungal species, or between fungi and bacteria or plants.

A perfect storm

Current problems have arisen because the adaptability of fungi has met modern agricultural practices.

Most monocultures entail vast areas of genetically uniform crops. (The world’s largest monoculture is a field of more than 14,000 hectares of genetically uniform wheat in Canada.) These provide ideal feeding and breeding grounds for such a prolific and fast-evolving group of organisms. Added to this, the increasingly widespread use of antifungal treatments that target a single fungal cellular process (for example, compounds called azoles target an enzyme needed for the formation of fungal cell membranes) has led to the emergence of fungicide resistance.

Ever harder to control. A line chart showing the increase of antifungal use in agriculture leading to higher resistance.
Source: T. M. Heick et al. in Applied Crop Protection 2018 Ch. 4 (DCA, 2018)

Together, the azoles, the strobilurins and the succinate dehydrogenase inhibitors (all of which are single-target-site antifungals) comprise more than 77% of the global fungicide market10. Moreover, between 2021 and 2028, the market for fungicides is projected to grow by around 4.9% per year — largely thanks to increasing use in low-income countries.

An open question is how the impacts of fungal diseases on crops will be affected by climate change. Although little is known about the response of major plant pathogens to climate change, increasing temperatures in the Northern Hemisphere will drive the evolution of new temperature tolerances in fungal pathogens, and the establishment of pathogens that previously were restricted to more southerly regions4,5. In fact, since the 1990s, fungal pathogens have been moving polewards at around 7 km per year4. Growers have already reported wheat stem rust infections — which normally occur in the tropics — in Ireland and England.

Increasing temperatures might also affect interactions between plants and their microbiomes, including endophytic fungi (symbionts that live in plants). Harmless endophytic fungi could become pathogenic as plants change their physiologies in response to environmental stresses11, which has been demonstrated in studies of the model plant Arabidopsis thaliana12. Moreover, tolerance to higher temperatures in fungi could increase the likelihood of opportunistic soil-dwelling pathogens hopping hosts, and becoming pathogenic in animals or humans13.

With the pressures on the food system from a growing human population added to these problems — over the next 30 years, the global population is projected to grow to 9.7 billion — humanity is on track for unprecedented challenges to food production.

Early promise

Better protecting the world’s crops from fungal disease will require a much more unified approach than has been achieved so far — with closer collaboration between farmers, the agricultural industry, plant breeders, plant-disease biologists, governments and policymakers, even philanthropic funders.

It is no longer enough to focus on crop husbandry (such as the clearing or burning of diseased plant tissues), conventional methods of breeding plants for single disease-resistance genes, or the spraying of predominantly single-target-site fungicides. Growers and other stakeholders must exploit various technical innovations to more effectively monitor, manage and mitigate plant disease. Several approaches are already being developed or used to limit disease impacts and protect crop yields; in combination, these approaches could help farmers to sustain their yields in the coming decades.

Discovery and development of antifungals. The development of fungicides has been largely orchestrated in the agrochemical crop-protection industry. It has so far relied on the serendipitous discovery of antifungals following large-scale screening of compounds, such as the by-products of the pharmaceutical industry — and, since the 1980s, on the synthesis of chemical variants of known compounds, such as the strobilurins and the azoles.

However, it is time to move away from reliance on single-target-site fungicides, and to search for compounds that target multiple processes in the pathogen. In 2020, an inter-disciplinary research team at the University of Exeter, UK, revealed an interesting candidate molecule — a lipophilic cation (C18-SMe2+) that targets several fungal processes (including the synthesis of the energy-carrying molecule ATP, as well as programmed cell death)14. This molecule provides significant crop protection against Septoria tritici blotch in wheat, rice blast in rice13 and Panama TR4 disease in bananas15.

A close-up of corn smut in a field of corn
Corn smut, a disease caused by the fungus Ustilago maydis, affects maize (corn) crops.Credit: Getty

Increasing diversity in agricultural fields. Planting seed mixtures that combine several crop cultivars carrying different resistance genes could provide an important way to slow down pathogen evolution.

In 2022, around 25% of the total wheat production in Denmark used mixed cultivars, selected because they grow at a similar pace and carry complementary disease-resistance genes. This collaborative venture (involving breeders, farmers, environmentalists and scientists) provided promising results in terms of reducing the severity of both Septoria tritici blotch and yellow and brown rust in mixed cultivars without incurring yield loss (L. Nistrup Jørgensen, pers. comm.).

Indeed, these cultivars could reduce the spread of disease and the erosion of crop-resistance genes16.

Early disease detection and surveillance. Artificial intelligence (AI), satellites, remote- sensing tools (such as drones), incentives to persuade farmers to report disease and community-science projects that engage the public in the reporting of plant diseases (both in crops and in wild species) are beginning to engender more effective surveillance of fungal disease.

A collaborative scientist initiative called OpenWheatBlast aims to collect research outputs and data on the emerging wheat blast disease. The fast and easy data sharing allows discoveries to be made, resulting in faster disease control (see go.nature.com/42s25a3). Meanwhile, for the Cape Citizen Science project, an initiative funded by Stellenbosch University in South Africa, researchers are asking people who are interested in science to hunt for the oomycete Phytophthora spp. in South African vegetation (https://citsci.co.za/disease/) — to create records of the presence and spread of this pathogen.

Data collected through AI, community- science projects and so on could be integrated with disease records and collated into, for example, the PlantwisePlus programme (see go.nature.com/3mlgxnn) led by the Centre for Agricultural and Bioscience International, a non-profit intergovernmental organization. The results could also be integrated with climate data obtained from meteorological offices (for example, see go.nature.com/3ukk5hu) and so inform the building of models that predict when and where plant fungal diseases will occur5. More accurate disease predictions could, in turn, trigger early interventions to offset the loss of crops.

A biosecurity sign stands in front of a banana farm on an overcast day
A quarantined banana farm near Cairns in Queensland, Australia.Credit: Suzanne Long/Alamy

Disease resistance and plant immunity. Conventional plant-breeding practices have involved introducing into a given cultivar one or two genes that confer resistance to a particular disease, known as R genes. But although pathogens can overcome this R-gene-mediated resistance in a few years, it can take 10–20 years to go from researchers unmasking an R gene to an agriculture company selling the new cultivar. Incorporating two or more R genes (known as R-gene pyramiding or stacking) can broaden resistance to a diversity of pathogens. Yet field studies have documented how resistance achieved through this means can be short-lived17.

Most R genes encode proteins with a nucleotide-binding site and a leucine-rich repeat region, which act as receptors in the plant cell. These receptors recognize particular pathogen-produced molecules. However, plants possess an earlier detection system for pathogens, involving extracellular receptor proteins that recognize pathogen elicitor molecules, such as chitin and glucan. (Chitin and glucan are present in the fungal cell wall.) These receptors are known as pattern-recognition receptors (PRRs). This type of ‘immune boosting’ could be combined with new R-gene-edited cultivars or through R-gene pyramiding using conventional breeding to provide more durable and broader resistance to major pathogens.

A significant barrier to exploiting this approach in a way that is fast and efficient — particularly in Europe — is public and political resistance to the use of transgenic plants. In March, however, the UK Genetic Technology (Precision Breeding) Act was passed into law; this will enable the development and marketing of gene-edited crops in the United Kingdom. In principle, practices such as ‘immune boosting’, combined with the incorporation of two or more R genes into crops, could endow more durable and broader disease resistance.

Exploiting biologics and crop biotics. Biologics are a broad category of products derived from living organisms. Just as interest in probiotics in medicine has grown over the past decade, so too has interest in the use of biologics in crop protection. This is evidenced by the projected rise in investment by governments and stakeholders.

Strategies currently being explored include the exploitation of living antagonists of plant pathogens, such as the fungus Trichoderma spp., and spraying crops with natural antimicrobial compounds, such as polyoxins, which inhibit the synthesis of chitin (for example, polyoxin D zinc salt)18. Trichoderma strains can impede fungal phytopathogens either indirectly, for example by competing for nutrients and space, or directly, by parasitizing fungi. And in the past decade, researchers have identified other fungal and bacterial endophytes that can help to suppress disease.Indigenous knowledge is key to sustainable food systems

Plants do not grow alone — they associate with diverse microbial communities, which can play a part in plant development, stress tolerance and disease resistance. Over the past decade, new methods for profiling microbes have revealed the existence of beneficial microbial networks. The discovery that some microbial species always co-occur, whereas others never do, is essential knowledge in the design of consortia of microbes that can be applied to soil to promote plant growth and enhance disease protection. Indeed, the challenges ahead will include translating these discoveries from laboratory settings to fields of crops, and ensuring that synthetic, beneficial microbial communities persist once they are introduced, and do not adversely affect the native microbiota, or become pathogenic themselves18.

RNA trafficking between plants and fungi. In 2013, a research team showed that small RNAs (sRNAs) from the grey mould fungus Botrytis cinerea can silence plant host genes involved in immunity19. Some of the researchers then showed that double stranded RNAs (dsRNAs) and sRNAs from the fungus could protect vegetables and fruit against grey mould disease for up to ten days20. However, RNAs (usually encapsulated in tiny vesicles) are not only transferred from the fungus to the host — plant hosts also dispatch vesicles to suppress fungal virulence genes.

A growing number of researchers and newly founded technology companies are now looking to harness these naturally occurring RNA interference (RNAi) based trafficking systems to better protect crops against fungal disease. Currently, investigators are exploring two possible ways of using RNAs. One of these, called host-induced gene silencing or HIGS, relies on the genetic modification of crops. But this approach is lengthy, costly and can’t be implemented in the many countries where genetically modified plants remain banned. Therefore the main focus is now on spray-induced gene silencing or SIGS, in which sRNAs or dsRNAs are directly applied to plants, as a new, environmentally friendly and non-genetically modified crop-protection strategy21.

Several studies have documented the efficacy of RNAi in providing resistance to common fungal pathogens22. However, research is still needed to understand how these external RNAs are taken up and transported between the plant and fungal cells. Moreover, although progress is being made in the application of RNAs to crops, questions remain about the stability of the molecules.

A global body for plant health

Between January 2020 and January 2023, the UK Research and Innovation (UKRI) council allocated around US$686 million to COVID-19 research, and almost 225,000 papers on COVID-19 were published globally. (We conducted a search on the Scopus and Web of Science databases, using ‘COVID’ and ‘SARS-CoV-2’ as keywords.) During the same period, the UKRI spent around $30 million on fungal crop research and, globally, around 4,000 papers on crops and fungal disease were published. (Scopus and Web of Science key words were ‘crops’ and ‘fungal disease’.) Given that food security engenders health and well-being, agriculture and farmers are arguably just as crucial to human health as medicine and health-care providers.

Addressing the threat to human health posed by fungal crop diseases will require greater engagement with the problem, and more investment in research from governments, philanthropic organizations and private companies.

The International Plant Protection Convention (IPPC) is a body supported by the FAO that aims to protect the world’s plant resources from pathogens. It is much less well known than other bodies that deal with threats to human well-being, such as the WHO. The 180 member states that are signatories of the IPPC treaty must work together to change that.

Because viruses and bacteria dominate as agents of human disease, these microbes have received much more attention than have fungi. Yet in crops, fungi are by far the most important agents of disease. The WHO’s list of fungal pathogens that infect humans is a step towards bringing more attention to this extraordinary but understudied group of microbes. But addressing the greatest threats to food security — and so to human health — must include tending to the devastating impacts fungi are having, and will keep having, on the world’s food supply.

Nature 617, 31-34 (2023)

doi: https://doi.org/10.1038/d41586-023-01465-4

References

  1. Fisher, M. C. & Denning, D. W. Nature Rev. Microbiol. 21, 211–212 (2023).Article  PubMed  Google Scholar 
  2. Steinberg, G. & Gurr, S. J. Fungal Genet. Biol. 144, 103476 (2020).Article  PubMed  Google Scholar 
  3. Fisher, M. C. et al. Nature 484, 186–194 (2012).Article  PubMed  Google Scholar 
  4. Bebber, D. P., Ramotowski, M. A. T. & Gurr, S. J. Nature Clim. Change 3, 985–988 (2013).Article  Google Scholar 
  5. Chaloner, T. M., Gurr, S. J. & Bebber, D. P. Nature Clim. Change 11, 710–715 (2021).Article  Google Scholar 
  6. Savary, S. et al. Nature Ecol. Evol. 3, 430–439 (2019).Article  PubMed  Google Scholar 
  7. Fones, H. & Gurr, S. Fungal Genet. Biol. 79, 3–7 (2015).Article  PubMed  Google Scholar 
  8. Brown, J. K. M. & Hovmøller, M. S. Science 297, 537–541 (2002).Article  PubMed  Google Scholar 
  9. Möller, M. & Stukenbrock, E. H. Nature Rev. Microbiol. 15, 756–771 (2017).Article  PubMed  Google Scholar 
  10. Oliver, R. P. & Hewitt, H. G. Fungicides in Crop Protection (CABI, 2014). Google Scholar 
  11. Karasov, T. L., Chae, E., Herman, J. J. & Bergelson, J. Plant Cell 29, 666–680 (2017).Article  PubMed  Google Scholar 
  12. Mesny, F. et al. Nature Commun. 12, 7227 (2021).Article  PubMed  Google Scholar 
  13. Garcia-Solache, M. A. & Casadevall, A. mBio 1, e00061-10 (2010).Article  PubMed  Google Scholar 
  14. Steinberg, G. et al. Nature Commun. 11, 1608 (2020).Article  PubMed  Google Scholar 
  15. Cannon, S. et al. PLoS Pathog. 18, e1010860 (2022).Article  PubMed  Google Scholar 
  16. Orellana-Torrejon, C., Vidal, T., Saint-Jean, S. & Suffert, F. Plant Pathol. 71, 1537–1549 (2022).Article  Google Scholar 
  17. Balesdent, M.-H. et al. Phytopathology 112, 2126–2137 (2022).Article  Google Scholar 
  18. Lahlali, R. et al. Microorganisms 10, 596 (2022).Article  PubMed  Google Scholar 
  19. Weiberg, A. et al. Science 342, 118–123 (2013).Article  PubMed  Google Scholar 
  20. Wang, M. et al. Nature Plants 2, 16151 (2016).Article  PubMed  Google Scholar 
  21. Wang, M. & Jin, H. Trends Microbiol. 25, 4–6 (2017).Article  PubMed  Google Scholar 
  22. Niu, D. et al. Curr. Opin. Biotechnol. 70, 204–212 (2021).Article  PubMed  Google Scholar 

Download references

Competing Interests

The authors declare no competing interests.

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily. Email address I agree my information will be processed in accordance with the Nature and Springer Nature Limited Privacy Policy.

Nature (Nature) ISSN 1476-4687 (online) ISSN 0028-0836 (print)

nature.com sitemap

About Nature Portfolio

Discover content

Publishing policies

Author & Researcher services

Libraries & institutions

Advertising & partnerships

Career development

Regional websites

© 2023 Springer Nature Limited https://www.mainadv.com/retargeting/live/zanox_rtg.aspx?Key=zx&visitorIp=Springerlink_DE&pageType=generic

New Zealand: Warming climate could deliver new crops, and blights.


May 5, 2023

Editors’ notes

by Better Border Biosecurity (B3) Credit: Pixabay/CC0 Public Domain

New, invasive plant-destroying insects, weeds and diseases will increasingly challenge New Zealand’s borders as a warming climate and other global “megatrends” make our plants and ecosystems more exposed and vulnerable; a new report proposes.

https://1cecf2ca2e0eddfcbd7d85fa2164c2c7.safeframe.googlesyndication.com/safeframe/1-0-40/html/container.html

The prediction is contained in the “Global Change and New Zealand Biosecurity” report, published today by the Better Border Biosecurity (B3) research collaboration. The report is the culmination of a two-year government funded B3 research project to review how global changes could impact New Zealand’s plant biosecurity system and the various productive and natural ecosystems it protects.

B3 is a national biosecurity collaboration that links world-class scientists with government agencies, industry and iwi to collectively strengthen New Zealand’s defenses and protect our precious plants.

B3 project leader Nicolas Meurisse was one of four report authors. The invasion ecologist says New Zealand is already experiencing the negative impacts of established invasive species and future changes in land use and agricultural practices will exacerbate some of these impacts. Other trends such as climate change and globally increasing pest emergences and movements will also challenge our ability to prevent future invasions.

“Biological invasions are already a big concern for New Zealand with its unique insular ecosystems and being home to one of the highest proportions of threatened indigenous species in the world. Our economy is also very dependent on our primary sector. We knew global change would bring more challenges so we began to study what these were likely to be and how we can prepare for them.”

The project team reviewed the many “global megatrends” that will affect our future and, specifically, New Zealand’s plant border biosecurity systems. They found megatrends and their impacts were interconnected and complex and the resulting future, consequently, extremely difficult to predict. However, megatrends such as changes in trade routes, extreme weather, sea and air currents, human movement, and international conflict are all likely to result in an increased risk of entry to New Zealand by “alien” plant pests.

Meurisse says one of the most predictable—and impactful—megatrends is rising CO2 levels and resulting warmer climates. This became a focus of the report. Climate change will affect our growing environments and the pests and diseases that threaten them, both “sleeper” threats already in New Zealand and new “alien” ones, and significantly affect future biosecurity risk.

The report found:

  • Existing crops, such as kiwifruit, citrus, grapes and avocados, may be grown in new areas as local climates change; new crops may become viable, such as peanuts, soybeans, chickpeas, quinoa, oats, pineapple, banana and rice. Other land use changes will likely favor more forestry and dairy industries, and reduced sheep and beef production.
  • These current and future crops, as well as plants in natural landscapes (which cannot be moved to suit warmer climates), will likely be threatened by new suites of pests, weeds and pathogens that may or may not already be present in New Zealand.
  • Predicting exactly which ‘alien’ pest and pathogen species will emerge and threaten New Zealand as a result of global change will be difficult, so New Zealand’s border biosecurity system must be robust, resilient and responsive to new threats as they appear. A key factor will be the health of our ecosystems and their resilience to extreme events, such as local floods, droughts, and wildfires. These events may facilitate spread of pests and diseases, which in turn affect the resilience of ecosystems to extreme events.

Meurisse says natural environments, such as native forests, may be especially vulnerable to invading biosecurity threats. These could be adversely impacted by the combined effects of biological invasions, climate warming and other human-related pressures.

The report says research is needed to address the biosecurity implications of global megatrends, including climate change and ensure New Zealand’s border system is robust, resilient and responsive to the wide range of future biosecurity challenges, both predictable and unpredictable. Examples include developing new methods to forecast, track and monitor changing border pressures, and better understanding the vulnerabilities of New Zealand plants and ecosystems and potential impacts of invasive pests and pathogens.

The report concludes: “It is impossible to predict the future, particularly in an area as complex as global change where so many factors are interacting. Preparing for future biosecurity challenges needs to be a collective task to ensure we are able to respond as needed to protect New Zealand’s unique plant systems.”

B3 Co Director Māori Alby Marsh says the collaboration has a new Māori Strategy that, among other things, recognizes Te Tiriti and the overarching principles of Partnership, Protection and Participation with Mana Whenua in all B3 research programs.

“It is important for us as researchers to be inclusive with our science by fostering deeper meaningful relationships to better understand mātauranga and develop programs of research that encourages broader representation and participation. The Global Change and New Zealand Biosecurity report highlights coming issues of huge importance for tangata whenua and the plants they grow and nurture. Mātauranga Māori experts are also observing this change and are trying to understand the impacts of climate warming. For example, ‘tohu’ or environmental indicators and the timing of their occurrence may be changing which could have a bearing on the timing of planting or harvest,” he says.

Provided by Better Border Biosecurity (B3)

Is the EU ready to join the global gene editing revolution?


Is the EU ready to join the global gene editing revolution?

Dr Petra Jorasch

May 2023

Science for Sustainable Agriculture

Facebook
Twitter
LinkedIn

Regulatory authorities around world are moving rapidly to clarify their stance on new plant breeding technologies such as gene editing. Nearly all are determining that certain gene edited crops should be regulated in the same way as conventionally bred crops, rather than as GMOs. As the European Commission prepares to unveil its plans for the future regulation of these techniques, is the EU ready to join the global gene editing revolution, or will we remain locked in a political and regulatory time warp, asks Dr Petra Jorasch.

Major new developments in gene editing are now taking place with increasing frequency, as the world looks to harness the potential of genetic innovation to tackle urgent global challenges of food security, improved nutrition, climate change and pressure on finite natural resources of land, energy and water.

Just in the past couple of months, for example, the Canadian Government confirmed that gene edited crops without foreign genes will be regulated in the same way as conventionally bred varieties, and the UK Parliament approved new legislation in England which removes gene edited, or ‘precision bred’, plants and animals from the scope of restrictive GMO rules. In doing so, they joined a growing list of countries around the world seeking to encourage the use of these more precise breeding methods, including the United States, Japan, Australia, Argentina and Brazil.   

Over the same period, the Chinese Government approved its first gene edited food crop, a soybean high in healthy oleic acid, the Philippines approved a gene edited ‘non-browning’ banana designed to reduce food waste, and the US authorities cleared a new type of mustard greens, gene edited for reduced bitterness and improved flavour.

Here in Europe, we continue to see major research breakthroughs in these technologies, including the recent announcement that researchers at Wageningen University in the Netherlands have used CRISPR/Cas gene editing technology to make potato plants resistant to late blight disease caused by Phytophthora infestans without inserting foreign DNA in the potato genome. It is hard to overstate the potential significance of this breakthrough, not only in safeguarding harvests from a devastating fungal infection, but also in reducing the need for pesticide sprays.       

As the pace of these exciting developments accelerates around the world, a key question set to be answered over the coming months is whether Europe will join in, or remain locked out?

The European Commission is preparing to publish its long-awaited proposal for future regulation of the products of new genomic techniques (NGT), which are currently classified as GMOs in line with a European Court ruling dating back to July 2018.

In a study following this ruling the Commission concluded that the EU’s 20-year-old GMO rules are ‘not fit for purpose’ to regulate these new breeding methods, largely because those regulations were put in place years before gene editing technologies were even dreamt of.

But will the Commission’s proposal follow other countries in determining that NGT plant products which could have occurred naturally or been produced by conventional means should be regulated in the same way as their conventionally bred counterparts? Or will it succumb to the anti-science lobby, imposing GMO-style traceability, labelling and coexistence obligations for these conventional-like NGTs, which will not only deter innovation and cement the EU’s future as a museum of agriculture, but also risk trade-related challenges as gene editing becomes one of the default delivery models for global crop genetic improvement?

Earlier this month, 20 European value chain organisations, including Euroseeds, signed a joint open letter urging the Commission to treat conventional-like NGT plants  in the same manner as their conventionally bred counterparts to avoid regulatory discrimination of similar products.

In the letter, all 20 organisations – representing EU farming, food and feed processing, plant breeding, scientific research and input supply organisations – underlined their commitment to transparency and information sharing to support customer and consumer choice.

Following the recent example of Canada, which has introduced a registry for gene edited plant varieties to ensure transparency and choice, the joint letter points out that national variety lists and the European Common Catalogue could be used to provide freedom of choice to farmers and growers, and allow value chains wishing to avoid the use of conventional-like NGT plants in their production to do so. Already today, for example, some private organic certification schemes exclude plant varieties bred using certain exempted methods of genetic modification such as cytoplast fusion. These private standards are observed, and the respective value chains co-exist, without the need for a specific regulatory framework, but through varietal information provided by the seed sector.

However, transparency does not necessarily imply a requirement for traceability (and/or labelling). Transparency stands at the beginning of value chains and, as such, does not disrupt food chain operations and product flows but provides freedom of choice for farmers and growers. A requirement for mandatory labelling of one particular breeding method would not only incur additional costs within the supply chain, but could also erroneously be perceived by some consumers as a warning statement and so discriminate unfairly against conventional-like NGT products. This in turn could prevent the potential of NGT plants to contribute to sustainable agricultural production and food security from being realised.

Where NGT plant products could equally have been produced using other conventional breeding methods (which are not subject to a mandatory labelling requirement), it would also constitute a breach of the fundamental principles of non-discrimination of like-products and factual information under General Food Law.

The joint value chain letter also highlighted the challenges of detection and identification of NGT plant products for market control and enforcement purposes. Since it is not technically possible to distinguish how the genetic change in a conventional-like NGT plant occurred (because it is conventional-like!), it is highly unlikely that laboratory tests would ever be able to detect and identify the presence of NGT-derived plant products in food or feed entering the EU market, creating enforcement issues and legal uncertainty for operators. The EU regulatory system risks losing trust if it is unenforceable and, with this, becomes vulnerable to fraud.   

Any mandatory traceability or segregation requirements (eg paper trail systems) for technically similar products would bring significant costs and logistical burdens for operators, which are not aligned with current food trade and processing operations, and as such would represent a further, unjustified barrier to the adoption of NGT plants in the EU.

Finally, in relation to the coexistence of farming systems and international trade, the joint letter points out that, today, EU regulations do not impose coexistence measures between conventional and organic farming, even though some organic farming standards already exclude plant varieties from certain non-regulated-GMO breeding methods. Similarly, the US, with which the EU has agreed equivalency schemes for organic food, does not impose specific coexistence measures between organic and conventional farmers (including for conventional-like NGT products). This has the obvious advantage for US organic growers and food producers that such food will also be accepted as organic in the EU. In sharp contrast, always imposing risk assessment and traceability plus labelling requirements (as well as coexistence measures) for conventional-like NGT plants and products would be incompatible with organic standards in third countries like the US. This would endanger well-established equivalency standards and international organic value chains.

In short, imposing traceability and labelling requirements, and coexistence measures that place specific obligations on farmers growing conventional-like NGT varieties, would have negative implications for the competitiveness of the EU agri-food value chain as well as the enforceability of regulations.

It would also be at odds with the EU’s guiding regulatory principles of practicality, proportionality and non-discrimination.  

Our policy-makers have a unique opportunity to embrace and enable the use of these more precise breeding technologies in European agriculture, and to improve prospects for delivering the sustainability objectives set out in the EU’s Green Deal.

Is the EU ready to join the global gene editing revolution, or will we remain locked in a political and regulatory time warp?

Petra Jorasch holds a PhD in plant molecular biology from the University of Hamburg. She is an internationally recognised science, communication and industry advocacy expert with more than 20 years of experience in and a deep knowledge of the relevant policy frameworks for seeds, plant science and breeding, access and use of plant genetic resources as well as relevant intellectual property protection systems. Petra worked for 13 years in the German seed sector at the interface of science and industry, managing intellectual property rights, public-private partnerships and technology transfer. From 2014-2017 she was Vice Secretary General of the German Plant Breeders’ Association (BDP) and its research branch GFPi (German Federation for Plant innovation). Petra joined Euroseeds in February 2017 as the spokesperson of the EU plant breeding sector on modern plant breeding methods and innovative technologies.

Social Media: LinkedIn: https://www.linkedin.com/in/petra-jorasch-57120a56/ 

Twitter: @pjorasch

Contact us

Montana, USA: Research into wheat stem sawfly biocontrol.


Reagan Colyer, MSU News Service
May 19, 2023

BOZEMAN – Research from a Montana State University alumna published recently in the journal Physiological Entomology could have tangible impact for Montana agricultural producers who deal with perennial damage from wheat stem sawflies. 

Laissa Cavallini, who completed her master’s degree in entomology in spring 2022, worked alongside professor David Weaver and department head Bob Peterson in the Department of Land Resources and Environmental Sciences in MSU’s College of Agriculture. The project examined two species of parasitic wasps that act as biocontrols for wheat stem sawfly. Cavallini explored the nutritional needs of those wasps to explore ways of boosting their effectiveness as biocontrols — a pest management tactic that involves using one organism to manage another.

The insects, called Bracon cephi and Bracon lissogaster, are small orange wasps that can detect the presence of wheat stem sawfly larvae inside a wheat stem. They then inject a paralyzing toxin into the sawfly larvae before laying their own eggs. When the wasp eggs hatch, the immature wasps kill and consume the immobilized sawfly.

B. lissogaster, a small wasp species that acts as a natural biocontrol to wheat stem sawfly, was the subject of a recent publication by MSU alumna Laissa Cavallini. Photo by Robert Peterson.

“Something interesting about these parasitoids and about wheat stem sawfly itself is that the organisms are all native,” said Cavallini, who completed her undergraduate work in her home country of Brazil before joining Weaver’s lab in 2018 as a graduate student. “What’s more, these two species are the only ones known to parasitize the wheat stem sawfly.”

That unique relationship means that B. cephi and B. lissogaster are naturally suited to act as biocontrols for wheat stem sawflies but are limited by a short lifespan in wheat fields. Cavallini’s work examined the nutritional needs of the parasitic wasps to see if their diet could increase their lifespan and potentially make them more effective management tools.

“I thought it was a nice opportunity to work with parasitoids and look into controlling insect pests in a way that’s less harmful to the environment,” said Cavallini. “We already knew that some parasitoids were able to feed on nectar, but we didn’t have a lot of information in the beginning. We saw an opportunity to see if that was the same here in Montana.”

Because Montana has a dry, arid climate, Cavallini said, it was necessary to identify whether the wasps could readily access plant nectar as a food and water source. Depending on the type of plant, a lack of water could mean the nectar forms crystals that are difficult to consume or, most often, the nectar is stored in a part of the plant that the small insects can’t easily reach. Cavallini built on research done by a previous graduate student, Dayane Reis, to determine whether ingesting sugar had an impact on the wasps’ lifespan. The insects were fed sucrose, the same type of sugar that they would get from plant nectar.

“We noticed that sugars helped them a lot,” Cavallini said. “They need this resource. Feeding on water, they would live for two to five days, and feeding on sugar, some of them lived for 60 days or longer.”

It was an important finding, Cavallini said, and it confirmed the hypothesis that nectar could make a large difference in the effectiveness of the parasitoids as biocontrols. But the team still had to gauge whether the wasps could access plant nectar on or near agricultural fields, so they next investigated whether the lab findings could be replicated in an agricultural setting and explored crops that could serve as a source of nectar.

Cowpea, a pulse crop that produces extrafloral nectar, could be a viable food source for two species of wasps that act as natural biocontrols for wheat stem sawflies.

Ultimately, the team identified cowpea as a potential partner crop to serve as a food source for the two parasitoid species. A type of pulse crop, cowpea was appealing for several reasons. It produces extrafloral nectar, meaning its nectar is more easily accessible for insects like B. cephi and B. lissogaster, providing an ideal food source to help them live longer and work more effectively in wheat stem sawfly management. Additionally, heat and drought tolerant cowpea also provides many of the same benefits as other pulse crops, like peas and lentils. It fixes nitrogen in soil, reducing the need for nitrogen fertilizer, and it helps to prevent erosion and maintain soil moisture, making it a good candidate as a rotational crop in years when a field may otherwise be left fallow, said Cavallini. 

“Another important part of this research is that we don’t have cowpea being widely grown in Montana,” she said. “We didn’t know if the parasitoids, which are native, would be attracted to it. But we found that they were able to perceive odors from cowpea plants and move to feed on the extrafloral nectar.”

Because the experiments with cowpea were done in a lab, Cavallini said field tests are needed to determine if those results can be replicated on a farm. She added that incorporating this biocontrol could be effective alongside the development of solid-stemmed wheat varieties that are more difficult for sawflies to burrow into. As Cavallini moves on to a doctoral program at North Carolina State University, she hopes future graduate students at MSU will continue those explorations.

“Altogether, this research has the potential to have important impacts on how wheat stem sawfly is managed in Montana,” Cavallini said.

David Weaver, Department of Land Resources and Environmental Sciences, weaver@montana.edu or 406-994-7608

Republishing

You may republish MSU News Service articles for free, online or in print. Questions? Contact us at msunews@montana.edu or 406-994-4565.

High-Resolution Images

For high-resolution promotional images visit the pressroom

Plant science’s biggest problems | Global Plant Protection News


Plant science’s biggest problems

May 20, 2023 – Science

Alison Snyder
Illustration of a microscope with a flower extending from the eyepiece and tube
Illustration: Natalie Peeples/Axios

Plant scientists are increasingly concerned about how plants will fare as climates change across the planet — and what role plants themselves can take in addressing one of the world’s most pressing problems.

Driving the news: A recent survey takes the pulse of the plant science community — a group of researchers whose subjects are often overlooked but critically support life on Earth.

  • An international panel of 15 researchers from five continents analyzed more than 600 questions collected from plant scientists, horticulturalists, gardeners, other experts and “botanically curious non-experts.”
  • They identified 100 pressing questions facing plant science, ranging from how plant scientists can collaborate with city designers and how plants can be grown in space to fundamental questions about plant pathogens and the genomes and evolution of plants.
  • More than 20% of the questions focused on climate change: how it will affect plant diseases and where plants can grow, as well as whether farming seaweed and other crops under the sea could reduce the impact of climate change, among other topics.

Flashback: When a similar survey was done in 2011 the questions focused more on what could be learned from plants.

  • “This time around the questions were more about, ‘what do we do to save them?’” says Emily May Armstrong, an interdisciplinary plant researcher and co-author of the study that appeared in New Phytologist.
  • There were also questions focused on determining which plants can best help the capture of carbon in soil, how plants can mitigate flooding, and how microbiomes can be leveraged to develop plants that can help to mitigate the effects of climate change.

What’s happening: Plant scientists are studying a range of climate-related topics. These include:

  • Seagrass as a way to capture and store carbon. A key question is what traits give these plants the ability to efficiently remove carbon.
  • Sequestering carbon in other plants — trees and crops.
  • Increasing the efficiency of photosynthesis and developing climate-resilient crops
  • Plants — such as switchgrass and black cottonwood — as a source of biofuel

What they’re saying: Climate change is “an enormous obstacle that will require a multidisciplinary approach. It affects molecular, physiological, ecological and all levels of plant growth and the plant life cycle,” says Marie Klein, a Ph.D. candidate at the University of California, Davis, who organized the “Plants in the Climate Crisis” symposium held last week at the university.

https://ce4c8b225ba31c32202c61bb80ff71b5.safeframe.googlesyndication.com/safeframe/1-0-40/html/container.html

What to watch: The survey organizers say the questions highlighted the importance of including scientists worldwide, insights from non-experts, and the need for more funding.

  • “This time they heard the voice of the Global South,” says Shyam Phartyal, a seed ecologist at Nalanda University in Rajgir, India, and co-author of the paper.
  • Plant sciences continue to struggle with biases: A recent study of more than 300,000 scientific articles published in the field over the past 20 years found “authors in Northern America arecited nearlytwice as many times as authors based in Sub-Saharan Africa and Latin America, despite publishing in journals with similar impact factors,” Rose Marks of Michigan State University and her colleagues wrote earlier this year in the journal PNAS.
  • They also found gender imbalances that tip to male authors and that most studies “focus on economically important crop and model species, and a wealth of biodiversity is underrepresented in the literature.”

https://ce4c8b225ba31c32202c61bb80ff71b5.safeframe.googlesyndication.com/safeframe/1-0-40/html/container.html

Australia: GM Fruit Claimed To Resist Panama Disease


May 21, 2023

Olga

Scientists from Australia’s Queensland University of Technology have submitted the results of their research — a genetically modified Cavendish banana — to regulators for approval, claiming that the fruit could serve as a safety net for the industry, which is suffering from the continued spread of the destructive Panama disease fungus, also known as Fusarium wilt.

The banana variety, known as QCAV-4, has been genetically modified to be resistant to Panama disease tropical race 4, which currently poses a grave threat to the global banana supply. The TR4 strain has had a severe impact on production throughout Southeast Asia, causing the Philippines, one of the world’s leading banana exporters, to slip from second to third place in last year’s global export rankings.

If authorized by regulators, QCAV-4 would become the first genetically modified fruit permitted for cultivation and consumption in Australia, as well as the world’s first approved genetically modified banana variety. However, even if the fruit is given a green light, the research team does not plan to immediately release it for commercial production or consumption. According to professor James Dale, who led the research on QCAV-4, the variety provides a potential remedy for growers in the event that Panama disease wipes out the Australian banana sector.

Cavendish bananas gained popularity after plantations of the previously dominant variety, Gros Michel, were ravaged by the Panama TR1 outbreak in the 1950s, and they now account for approximately half of commercial banana production globally. The TR4 strain, which emerged in Taiwan in the 1990s and quickly spread to China, Indonesia, Malaysia, the Philippines and even northern Australia, is now threatening the Cavendish cultivar, which was previously thought to be resistant to Fusarium wilt. The TR4 strain was also detected in Colombia in 2019, Peru in 2021 and Venezuela in 2023, raising fears about the potential eradication of much of the world’s banana crop, given that Latin America and the Caribbean dominate the global supply. In 2022, approximately 77% of the world’s banana exports originated from Latin America and the Caribbean, followed by 20% from Asia and the remainder from Africa.

QCAV-4 was engineered over 20 years of research by introducing a resistance gene from a wild banana that is immune to TR4 into the Cavendish. “We did a much, much bigger field trial that we planted in 2018, and that’s still going,” Dale said. After four years of trials, the QCAV-4 variety had a 2% infection rate, compared with rates of 95% and 75% in two lots of regular Cavendish plants. “If the disease gets going [in Australia] like it has in the Philippines … we’ve got this banana in the back pocket and we’ll be able to pull it out,” he noted.

In the opinion of Australia’s Office of the Gene Technology Regulator, the recent achievement represents a significant milestone; nonetheless, there are still many steps to be taken. A spokesperson for the regulator stated that “the gene technology regulator will carefully examine any risks to people and the environment posed by the commercial cultivation of the GM banana plants,” adding that a permit to grow GM bananas would only be granted if there is assurance that any risks that arise can be managed effectively. In addition to two stakeholder consultation sessions, there will also be a public consultation, which is scheduled to take place in August.

The approval of genetically modified bananas is subject to fruit and environmental safety assessments conducted by the authorities. Another question is whether the approved fruit will gain the trust of consumers. Previously, when Dale’s trials were underway, industry insiders offered a variety of opinions. Some voiced concern that genetically modified bananas would not be accepted on the market. Opponents of genetically modified fruit also urged seeking out traditionally bred alternatives, including cultivars other than Cavendish, some of which are regarded to be even more nutritious and taste better.

Image: iStock

Topics: 

Food Safety

Policy

Production

Regions: 

Global

Australia

Produce: 

Bananas