Research Results
1. A new method for measuring RNAi pesticide in soil
A new generation of gene-silencing double-stranded RNA (dsRNA) molecules is being used as a novel class of biopesticides. These RNAi pesticides, which work by interfering with the functioning of RNA in crop-killing pests, are genetically engineered into crops, giving the plants their defence against pests. There is a need to assess the ecological risk associated with their release to the receiving environments. Until recently, there was no method to measure the amount of pesticide present in the dynamic environment of agricultural soil.
Researchers at the McKelvey School of Engineering at Washington University, St. Louis, have published their technique for measuring just how much of RNAi pesticide is present in a few grams of soil. To understand how these RNAi pesticides behave in the real-world, “we needed to be able to determine what happens to them in the environment,” said Kimberly Parker, the lead scientist. Initially, they determined the forces acting on RNAi pesticides as they moved through the soil in a lab. Once the molecule was isolated, the team could use quantitative reverse transcription-polymerase chain reaction, a method for measuring the amount of a specific RNA, including RNAi pesticides. This approach can be applied to assess the environmental fate of dsRNA biopesticides at concentrations relevant to their release to soils.
Access the abstract at https://pubs.acs.org/doi/abs/10.1021/acs.est.9b07781#
2. How to boost plant biomass: Biologists uncover a molecular link between nutrient availability and growth
To date, the underlying mechanisms by which plants adjust their growth according to the nitrogen dose has been unknown. Knowing that could help farmers enhance plant growth using limited amounts of fertilizer. A new study by a research team led by Gloria Coruzzi, Carroll & Milton Petrie Professor in the Department of Biology and Center for Genomics & Systems Biology, New York University, has discovered the missing piece in the molecular link between a plant’s perception of the nitrogen dose in its environment and the dose-responsive changes in its biomass.
Transcription factors (TFs) can act as “catalysts,” driving rates of transcript change in response to nutrient dose. Supporting this, the study identified TGA1 (TGACG SEQUENCE-SPECIFIC BINDING PROTEIN 1) as a TF that controls nitrogen-dose–dependent rates of transcriptional change and plant growth. The team found that increasing the level of the transcription factor TGA1 accelerated the rates of nitrogen-dose responsive gene expression and the rate of plant growth. The plants that overexpressed TGA1 had increased growth rates in response to nitrogen, reaching plant biomass three times greater than wild type plants. “By modelling the transcriptome kinetics underlying nitrogen-dose sensing, using a classic principle of Michaelis-Menten kinetics, we discovered a regulatory gene whose increased expression may boost crop growth within low-nitrogen soils,” said Coruzzi. “Because TGA1 is conserved in plants, including crops such as rice, tomatoes, and wheat, our findings have implications for improving nitrogen-use efficiency in crops, which can benefit agriculture and sustainability.”
For more, see https://phys.org/news/2020-05-boost-biomass-biologists-uncover-molecular.html
Access the full paper at https://www.pnas.org/content/117/23/12531
3. Wounded plants: How they coordinate their healing
Plants are sessile organisms that cannot evade wounding or pathogen attack, and their cells are encapsulated within cell walls, which makes it impossible to use cell migration for wound healing, as is done with animals. Thus, regeneration in plants relies on the coordination of targeted cell expansion and oriented cell division. Researchers at the Institute of Science and Technology Austria, Klosterneuburg, Austria, led by Lukas Hoermayer, have demonstrated that it is in the root that the major growth hormone auxin is specifically activated in wound-adjacent cells, regulating cell expansion, cell division rates, and regeneration-involved transcription factor (Ethylene-responsive 115) ERF115.
The authors conclude that these wound responses depend on cell collapse of the eliminated cells, presumably perceived by the cell damage-induced changes in cellular pressure. Information generated by this study broadens our understanding of how wound responses are coordinated on a cellular level to mediate wound healing and prevent over proliferation.
For more, see the full article athttps://www.pnas.org/content/117/26/15322
4. Understanding changing insect appetite crucial in protecting food sources of the future
The changing climate affects the distribution of many living beings, including insects. A study, published in Nature Ecology & Evolution, suggests that as warming climates drive insect species out of the tropics and to cooler, high latitude locations, they are often forced to expand or switch up what they eat. This portends shifts in crop pests and hence food production practices.
Lesley T. Lancaster, University of Aberdeen, School of Biological Sciences, Aberdeen, UK, says a study they did has given results that may be different from the earlier expectations regarding the importance of local adaptation. The results of the study suggest that with increased temperatures, the migrating pests may attack new crop varieties or spread diseases among a wider variety of crops in the new region to which the pests have moved. Such a change in host-pest interactions will have some degree of economic consequences, due to crop losses in the new region compared with the previous years. If predictive models could be developed for anticipating changes in pest-host dynamics, appropriate steps can be taken to monitor and protect crops to ensure food security.
For more, see https://phys.org/news/2020-05-insect-appetite-crucial-food-sources.html
Access the abstract at https://www.nature.com/articles/s41559-020-1199-1
5. Plant biologists discover a simple principle of plant responses to hormone
In a new study, researchers from Laboratory of Biochemistry, Wageningen University, Wageningen, the Netherlands, and colleagues in Japan and Spain, have found a simple mechanism for control of plant growth. The enormously complex response to the plant hormone auxin can be reduced to a very simple switch-like model. Basically, auxin toggles one gene switch from ‘off’ to ‘on,’ and at the same time, a second factor competes with this switch and thereby determines how sensitive each cell is to the hormone.
“This leap in our understanding of how cells respond to the hormone gives unprecedented new abilities to modify cellular hormone responses in crop plants, where propagation, rooting, and many other traits depend on auxin response”, says Dolf Weijers, head of the Laboratory of Biochemistry and leader of the research team. For decades, studies in flowering plants, including the model plant Arabidopsis, have led to the idea that plants use a very complex network of response factors to allow different plant cells to respond in different ways to the same hormone. Now, the research team describes their discovery of a very simple principle underlying the complex responses to the plant hormone auxin.
For more, see https://phys.org/news/2020-05-biologists-simple-principle-responses-hormone.html
Access the abstract at https://www.nature.com/articles/s41477-020-0662-y
6. Plants pass on ‘memory’ of stress to some progeny, making them more resilient
By manipulating the expression of one gene, geneticists can induce a form of “stress memory” in plants that is inherited by some progeny, giving them the potential for more vigorous, hardy, and productive growth, according to Penn State researchers, who suggest the discovery has significant implications for plant breeding. Plants that “detect” stress after the MutS HOMOLOGUE 1 (MSH1) gene is silenced can adjust their growth and change root configuration, limit above-ground biomass, delay flowering time, and alter their response to environmental stimuli.
Sally Mackenzie, professor of plant science in the College of Agricultural Sciences and professor of biology in the Eberly College of Science, says the study has shown that the memory condition is heritable by progeny but does not occur in all the offspring—so that there are memory and non-memory full siblings. This variable inheritance results in definable gene expression changes that impact a plant’s phenotypic ‘plasticity. “We suggest that all plants have this capacity and that the condition that we describe is likely to be an important part of how plants transmit the memory of their environment to precondition progeny,” she adds.
Because researchers can now identify gene networks that appear to be targeted by this manipulation, they report that plants have mechanisms designed to address stress or alter growth, and these can be accessed. The researchers grew five generations of Arabidopsis to study “memory” and “non-memory” plants. In follow-up research already underway in Mackenzie’s lab, the researchers have suppressed MSH1 genes in tomato and soybean plants, and grafting experiments have been field-tested with excellent yield results.
Potential Crops/Technologies
1. Injecting bacteria into rice paddies could reduce methane by over 90%
Rice is a staple food for millions worldwide. But this comes at a huge cost to the environment: rice farming contributes 11% of anthropogenic methane to the atmosphere. Methane is the second most important greenhouse gas after carbon dioxide, but it is several times more potent than carbon dioxide. However, a group of scientists from Denmark and Germany, led by Vincent V. Scholz, Center for Electromicrobiology, Aarhus University, Denmark, think that a recently discovered bacteria might hold the solution. They found that inoculating the soil with these microbes caused a striking decline in the methane of over 90%. That could help make a dent in harmful greenhouse gas emissions if the results carry through to field trials.
Cable bacteria are filamentous bacteria that conduct electricity across distances over 1 cm in sediment and groundwater aquifers. They are known to increase sulphate levels via electrogenic sulphide oxidation. The study has shown that one-time inoculation of rice-vegetated soil pots with cable bacteria increases the sulphate inventory 5-fold, which leads to the reduction of methane emissions by 93%, compared to control pots lacking cable bacteria. Promoting cable bacteria in rice fields by enrichment or sensible management may thus become a strategy to reduce anthropogenic methane emissions.
Access the full paper at https://www.nature.com/articles/s41467-020-15812-w
2. CRISPR plants: new non-GMO method to edit plants
An NC State researcher has developed a new way to get CRISPR/Cas9 into plant cells without inserting foreign DNA. This allows for precise genetic deletions or replacements, without inserting foreign DNA. Therefore, the end product is not a genetically modified organism or GMO. CRISPR/Cas9 is a tool that can be used to precisely cut and remove or replace a specific genetic sequence. The technique was demonstrated by Wusheng Liu, a plant biologist and biotechnologist in the Department of Horticultural Science. “This was the first time anyone has come up with a method to deliver the Cas9 protein through lipofection into plant cells,” Liu said.
The liposome binds to, and then fuses with, the plant cellular membrane, introducing its CRISPR cargo into the plant cell. The most common method of introducing DNA into plants is called Agrobacterium-mediated transformation. Scientists cannot control where the new DNA is added to the plant genome with that method, said Liu. Results show that the newly developed lipofection-mediated transfection approach is robust for the use of the DNA-free Cas9/gRNA technology for genome editing in plant cells.
For more, see https://phys.org/news/2020-05-crispr-non-gmo-method.html?utm_source=nwletter&utm_medium=email&utm_campaign=daily-nwletter
Access the abstract at https://link.springer.com/article/10.1007/s00299-019-02488-w
3. Roadmap for Accelerated Domestication of an Emerging Perennial Grain Crop
Crop production is facing unprecedented challenges. In 2050, the human population will likely exceed 9 billion, increasing the demand for staple crops and livestock by 60%. Climate change is expected to drastically constrain plant productivity. Developing higher-yielding, stress-tolerant, perennial grain crops could be a very valuable addition to the portfolio of crops available to farmers.
Domestication genes of the annual grass wheat are very well conserved in the perennial intermediate wheatgrass (Thinopyrum intermedium), providing an opportunity for accelerated domestication of a perennial grain using a mutagenesis approach. Molecular genetic studies by a group of scientists led by Michael Palmgren of NovoCrops Center, Department of Plant and Environmental Sciences, University of Copenhagen, Denmark, have revealed several domestication genes in plants, loci underlying crop diversity, and mutations that result in cis-regulatory changes. Many domestication genes have been discovered in a variety of crop plants.
The studies reported here highlight protein-coding sequences in the recently released T. intermedium genome sequence that may be orthologous to domestication genes identified in annual grain crops. Their presence suggests a roadmap for the accelerated domestication of this plant, using new breeding technologies.
For more, see (also the full article) https://www.cell.com/trends/plant-science/fulltext/S1360-1385(20)30053-4?dgcid=raven_jbs_etoc_email
4. Scientists discover a mutation that enhances plant defence
Sometimes, scientists begin to research and find exactly what they expected. At other times, they discover something unexpected. Such was the case for a group of scientists studying plant stress responses who stumbled upon a new mutation that enhances plant defence. “The discovery of this mutation was a surprise,” said first author Matt Neubauer, Department of Biology, Indiana University, USA (the work is done in collaboration with researchers at the Max-Planck Institute for Plant Breeding Research, Germany). “And by trying to better understand this new mutation, and what effect it had on plant stress responses, we uncovered new information about how different plant stress regulators function.” The mutation was named PAD4, a spontaneous mutation.
The scientists were working on a stress-regulating gene, known as ENHANCED DISEASE RESISTANCE1 (EDR1), when they identified a new gain-of-function mutation in a second gene, named PHYTOALEXIN DEFICIENT4 (PAD4), a gene that regulates plant responses to biotic stress.”The discovery that EDR1 may directly regulate PAD4 enhances our knowledge of how plants control stress responses,” said Neubauer, while acknowledging that there is still more to learn. “Ultimately we were unable to show how this new mutation makes PAD4 more active.”
Access the full paper at https://apsjournals.apsnet.org/doi/pdf/10.1094/MPMI-12-19-0339-R
5. New test could guarantee the perfect avocado
Consumers increasingly desire ready-to-eat avocado fruit. Since it is not easy to determine when exactly the fruit reaches this stage, producers and suppliers incur considerable losses due to destructive sampling. The current way to test ripeness is through a pneumatic device which pushes into the fruit, or by manual testing. Up to 30% of avocado fruit is thus wasted during grading, with a further 5% loss at retail.
The wastage due to destructive testing and inaccurate assessment of firmness is thus significant. A technique for measuring the ripeness of avocados could reduce waste and help fulfil consumer demand for ready-to-eat fruit. Developed and tested by Leon Terry and colleagues at the Plant Science Laboratory, Cranfield University, UK, the technology uses a laser and small vibration to test the individual fruits’ resonant frequency, giving a reliable assessment of ripeness without damaging the avocado. Laser Doppler vibrometry (LDV) beams a laser at the fruit to measure refracted light and uses small vibrations to test the resonant frequency. The LDV test could accurately predict the ready-to-eat stage of avocado fruit. The new technique for measuring the ripeness of avocados could reduce waste by up to 10% and help fulfil consumer demand for ready-to-eat fruit.
For more, see https://phys.org/news/2020-05-avocado.html?utm_source=nwletter&utm_medium=email&utm_campaign=daily-nwletter
Access the abstract at
https://www.sciencedirect.com/science/article/abs/pii/S1537511020300866?via%3Dihub
News:
1. Underestimation of irrigated crops risks water shortages
Collaborative research by the University of Reading, University of Bergen, and Princeton University shows that the amount of land that will need to be irrigated to raise crops by 2050 has been severely underestimated by computer models that do not take into account many uncertainties, such as population changes and availability of water.
Dr Samuele Lo Piano, a postdoctoral researcher in the School of the Built Environment at the University of Reading, who co-authored the study, said: “If the amount of water needed to grow our food is much larger than calculated, this could put severe pressure on water supplies for agriculture as well as homes. These findings show we need strategies to suit a range of possible scenarios and have plans in place to cope with unexpected water shortages.” Agricultural land where crops cannot be supported by rainwater alone is often irrigated by channelling water from rivers or springs, sprinkler systems, or by controlled flooding. The authors conclude that without accounting for the wide distribution of irrigated areas in the future, any modelling exercise focused on projecting irrigation‐related variables runs the risk of dramatically minimizing, or directly ignoring, the latent environmental impact of irrigated agriculture.
Access the full paper at
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2020GL087360
2. Webtool created by researchers helps predict climate change in agriculture
A webtool giving an overview of climate change in Europe and predicting subsequent developments was created as a collaborative effort of French, Spanish, German, and Estonian researchers. Climate change is one of the main challenges facing the entire world, and especially the agricultural sector, noted Associate Professor at the Estonian University of Life Sciences Institute of Veterinary Medicine and Animal Sciences, Ragnar Leming. This webtool aims to give an overview of climatic changes over the last 30 years and projections for the coming 30 years in the different agricultural regions in Europe.
The webtool allows one to look at various agroclimatic data, climate projections, and possible adaptation measures for each specific area. According to Leming, European farmers must adapt to the changing climate and adopt measures which would ensure the continued good productivity for the farms in the future. He noted that initially, adaptation plans must be created to reduce vulnerability and ensure the sustained development of the farm.
For more, see https://phys.org/news/2020-05-webtool-climate-agriculture.html?utm_source=nwletter&utm_medium=email&utm_campaign=daily-nwletter and https://awa.agriadapt.eu/en
3. Global agricultural economic water scarcity
There will be increased demand for water to irrigate crops, and of fertilizers to increase soil nutrients so as to achieve high yields per unit area. In order to control land-use change and better manage use of water, an international team of researchers led by Lorenzo Rosa of the Department of Environmental Science, Policy, and Management, University of California, Berkeley, USA, has developed a monthly agro-hydrological analysis to map agricultural regions affected by agricultural economic water scarcity.
“Agricultural economic water scarcity” is defined as lack of irrigation due to limited institutional and economic capability, instead of hydrologic constraints. To date, the location and productivity potential of economically water scarce croplands remain unknown. Researchers developed a monthly agro-hydrological analysis to map agricultural regions affected by agricultural economic water scarcity. We find these regions account for up to 25% of the global croplands, mostly across Sub-Saharan Africa, Eastern Europe, and Central Asia. Sustainable irrigation of economically water scarce croplands could feed an additional 840 million people while preventing further aggravation of blue water scarcity.
Access the full paper at https://advances.sciencemag.org/content/6/18/eaaz6031
4. Rising temperatures likely to increase the damage caused by plant pathogens
New research in Nature Climate Change provides evidence that rising temperatures are likely to increase crop losses as warmer soils favour the growth of pathogenic soil fungi species. Researchers led by Manuel Delgado-Baquerizo of Departamento de SistemasFísicos, Químicos y Naturales, Universidad Pablo de Olavide, Spain, have found that as air and soil temperatures progressively rise, the types of fungi likely to damage food plant species are also projected to increase over the next three decades. “Soil-borne plant pathogens already cause hundreds of billions of dollars in crop losses each year,” said Professor Brajesh Singh, one of the authors of the research paper.
“Our study suggests that common plant pathogens such as Fusarium and Alternaria species will become more prevalent under projected global warming scenarios, which will add to the challenges of maintaining world food production alongside other climate change-driven crises and a burgeoning human population,” Professor Singh said.
For more, see https://phys.org/news/2020-05-temperatures-pathogens.html?utm_source=nwletter&utm_medium=email&utm_campaign=daily-nwletter
Access the abstract at https://www.nature.com/articles/s41558-020-0759-3
5. Most climate and agriculture research has focused on crops, not the people who pick them
The coronavirus pandemic has highlighted the importance of people who grow, pick, and process food as essential workers. Such agricultural workers will also be on the front lines of climate change, a new study by Michelle Tigchelaar of the Department of Atmospheric Sciences, University of Washington, and others makes clear. They used climate data from a government database covering 1979-2013, to calculate agricultural workers’ historical exposure to extreme heat. With 2 °C of global average warming, which is expected around mid-century even if carbon emissions peak within the next two decades, “the average U.S. crop worker will face heat extremes of 101.4 °F,” the researchers write in the journal Environmental Research Letters.
In the Southeast, “the entirety of the growing season will be considered unsafe for agricultural work with present-day work practices,” the researchers write. Combining two adaptive measures—resting more plus resting in air conditioning, resting more or working more slowly plus breathable clothing—could result in less heat exposure for workers in a 4 °C warmer world than workers experience under current climate and working conditions, the study found.
For more, see https://www.anthropocenemagazine.org/2020/05/the-high-toll-of-climate-change-on-farm-workers-health/
Access the full paper at https://iopscience.iop.org/article/10.1088/1748-9326/ab86f4
6. Covid-19 Impact on Farmers: Time to re-orient returned migrants and make the rural economy vibrant again
The Covid-19 epidemic is spreading rapidly across India, and the number of patients infected with coronavirus is increasing. It impacts significantly on farmers and crop production. Due to the fear of virus infection and lockdown, farmers have been facing many problems in harvesting and marketing the crop produce. A quick view of the issues faced by the farmers of Bundelkhand region, along with their response to the situation as well as Government interventions, by a team at the Indian Agricultural Research Institute, led by Dr S. Naresh Kumar, Dr Om Prakash, and Jitender Kumar Gupta, identified the ground-level impact in some villages of Bundelkhand region.
To save the crop from wastage, farmers are trying to harvest and transport it themselves. In such a situation, farmers are looking for options to sell the crop directly from the farm field, so that they can get some money for their produce. The absence of labourers forced many farmers to harvest the crop by involving their entire family and by taking help from neighbours.
For more, see https://indiainternationaltimes.com/covid-19-time-to-re-orient-returned-migrants-and-make-rural-economy-vibrant-again/4094
Events
1. ICEAB 2020: International Conference on Ecological Agriculture and Biodiversity 2020. 10-11 Dec 2020, Rome, Italy.
For details, see https://waset.org/ecological-agriculture-and-biodiversity-conference-in-december-2020-in-rome
2. ICSACB 2021: International Conference on Sustainable Agriculture and Crop Breeding. 14-15 Jan 2021, Zurich, Switzerland.
For details, seehttps://waset.org/sustainable-agriculture-and-crop-breeding-conference-in-january-2021-in-zurich
3. ICBDASF 2021: 15th International Conference on Big Data in Agriculture and Smart Farming. 18-19 Jan 2021, Rome, Italy.
For details, see https://waset.org/big-data-in-agriculture-and-smart-farming-conference-in-january-2021-in-rome
Other Topics of Interest
1. Soybean seeding rates and risk
For more, see https://phys.org/news/2020-05-soybean-seeding.html?utm_source=nwletter&utm_medium=email&utm_campaign=daily-nwletter
2. Satellite maps can help nations make critical food production decisions amid coronavirus
For more, see https://wle.cgiar.org/thrive/2020/04/17/satellite-maps-can-help-nations-make-critical-food-production-decisions-amid
3. COVID effects promote ICT in agriculture
For more, see https://www.dailyexcelsior.com/covid-effect-promote-ict-in-agriculture/
4. Saving our planet starts in the Soil
5. Asafoetida cultivation: unknown facts on hing
For more, see https://krishijagran.com/agripedia/asafoetida-cultivation-unknown-facts-on-hings/
6. Nanotechnology applications can boost agricultural output in emergenciesFor more, see https://india.mongabay.com/2020/05/nanotechnology-applications-can-boost-agricultural-output-in-emergencies/#:~:text=Nanotechnology%20application%20to%20boost%20crop%20productivity%20can%20be,production%20of%20certain%20crops%2C%20said%20scientists%20at%20IIT-Kanpur.
7. ‘Alarming’ use of critical human antibiotics on crops
8. Parasitic wasp discovery offers chemical-free pest control for growers
For more, see https://phys.org/news/2020-05-parasitic-wasp-discovery-chemical-free-pest.html
Access the full paper at https://onlinelibrary.wiley.com/doi/full/10.1111/eea.12910
9. New software supports decision-making for breeding
For more, see https://eurekalert.org/pub_releases/2020-05/uog-nss051220.php
Access the full paper at https://www.g3journal.org/content/10/6/1915
10. India’s ‘superfood’ jackfruit goes global
11. The United States relaxes rules for biotech crops
For more, see https://www.sciencemag.org/news/2020/05/united-states-relaxes-rules-biotech-crops
12. The scientific debate over peanut origin laid to rest
For more, see http://www.news.uwa.edu.au/2020052112100/agriculture/scientific-debate-over-peanut-origin-laid-rest
13. Game-changing technologies to transform food systems
Access the abstract at https://www.nature.com/articles/s43016-020-0074-1
Very useful articles, especially on new research findings in plant metabolism, wound healing, adaptation to climate change etc. are enhancing ones knowledge on the latest research findings.