Research Results

1. Scientists create virus-resistant tomato plants

Researchers of Valencia’s Polytechnic University (UPV) and the Spanish National Research Council (CSIC) have used tools that regulate gene expression to produce tomato plants that are resistant to the spotted wilt virus (TSWV), thus proving the usefulness of this strategy to generate crops that are resistant to viral infections. “With our work, we have been able to produce tomato plants that are resistant to TSWV, proving the use and suitability of the strategy based on syn-tasiRNAs to generate crops that are resistant to viral infections,” says Alberto Carbonell, the senior author of the study.

“One of the most successful RNAi-based antiviral techniques consists of inducing the expression of small artificial RNAs designed to inhibit the replication of the most viral RNAs in plants,” Carbonell adds. On the other hand, a majority of plants that simultaneously express four antiviral syn-tasiRNAs (synthetic trans-acting small interfering RNAs) are resistant to TSWV, probably due to the combined effect of each syn-tasiRNA. In this study, researchers worked with two types of small artificial RNAs, artificial microRNAs or amiRNAs, and syn-tasiRNAs. The gene silencing mediated by RNA or RNAi allows for the selective activation or deactivation of genes; in plants, it has been successfully used to induce resistance to some viruses.

For more, see https://phys.org/news/2020-02-scientists-virus-resistant-tomato.html?utm_source=nwletter&utm_medium=email&utm_campaign=daily-nwletter

Access the full article at

https://onlinelibrary.wiley.com/doi/epdf/10.1111/tpj.14466

2. The impact of conventional and organic farming on soil biodiversity conservation

A detailed study on termites was carried out by David Bautze of the Department of International Cooperation, Research Institute of Organic Agriculture, Switzerland, in collaboration with several Kenyan researchers by conducting trials to determine how four farming systems (Conventional-Low inputs, Organic-Low inputs, Conventional-High inputs and Organic-High inputs) affected termite population and activity in a long-term experiment. Parameters studied included the influence of (i) abundance, incidence, and foraging activities of termites (total and casts); and (ii) diversity of termite genus. Further, the study aimed to explore how the different environmental conditions (trial sites), crop patterns (cropping seasons with different crops), and soil depths (substrate, topsoil, and subsoil) influence the termite presence, activity, and diversity in the various farming systems.

The results of the study showed higher termite abundance, incidence, activity, and diversity in Org-High compared to Conv-High, Conv-Low, and Org-Low treatments. At the same time, the termite presence in each system was also dependent on soil depth, trial site, and cropping season. During the experiment, nine different termite genera were identified, that belong to three subfamilies: (i) Macrotermitinae (genera: Allodontotermes, Ancistrotermes, Macrotermes, Microtermes, Odontotermes and Pseudocanthotermes), (ii) Termitinae (Amitermes and Cubitermes) and (iii) Nasutitiermitinae (Trinervitermes).

Authors note that that the presence of termites within the different farming systems might be influenced by the types of input applied, the soil moisture content, and the occurrence of natural enemies. These findings further demonstrate that the organic high-input system attracts termites, which are an important, and often beneficial, component of soil fauna. This further increases the potential of such systems in enhancing sustainable agricultural production in Kenya.

For more, see

https://bmcecol.biomedcentral.com/articles/10.1186/s12898-020-00282-x

3. 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. By adjusting the epigenetic architecture of a plant, researchers were able to access its resiliency network, and see how genes are expressed quickly and broadly to adjust a plant’s growth to adapt to the environment, noted Sally Mackenzie, director of the Plant Institute at Penn State.

“When a plant experiences stress such as drought or prolonged extreme heat, it can adjust quickly to its environment to become phenotypically ‘plastic’—or flexible.” There are many ways to inactivate the MSH1 gene, researchers explain, and in this context, they all work.” One gene, MSH1, gives us access to what is controlling a broad array of plant resiliency networks,” said Mackenzie, professor of plant science in the College of Agricultural Sciences and professor of biology in the Eberly College of Science.

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. And because the technique is epigenetic—involving the expression of existing genes and not the introduction of new genetic material from another plant—crops bred using this technology could sidestep controversy associated with genetically modified organisms and food.

For more, see

https://www.sciencedaily.com/releases/2020/05/200505121703.htm

4. Algae in the oceans often steal genes from bacteria

Algae in the oceans often steal genes from bacteria to gain beneficial attributes, such as the ability to tolerate stressful environments or break down carbohydrates for food, according to a Rutgers co-authored study. This study demonstrates that adaptation to a challenging environment can be directly facilitated by stolen genes. Finding such phenomena in nature inspires scientists to figure out how gene theft happens, and they can use these rules of nature to develop novel genetic engineering methods in the lab to benefit humans.

“The role of stolen genes in eukaryotes, which include most living things such as algae, has been hotly debated and many think it is unimportant and plays little to no role in their biology,” said co-author Debashish Bhattacharya, a Distinguished Professor in the Department of Biochemistry and Microbiology at Rutgers University-New Brunswick.

Ten species of red algae stole about 1% of their genes from bacteria to cope with toxic metals and salt stress in hot springs. These red algal species, known as Cyanidiales, also stole many genes that allow them to absorb and process different sources of carbon in the environment to provide additional sources of energy and supplement their photosynthetic lifestyle.

(Note: This is an example of genetic modification occurring spontaneously in nature)

For more, see https://phys.org/news/2019-07-red-algae-genes-bacteria-cope.html

5. How to boost plant biomass

Plant scientists have long known that crop yield is proportional to the dose of nitrogen fertilizer, but the increased use of fertilizers is costly and harmful to the environment. An increase in nutrient dose leads to proportional increases in crop biomass and agricultural yield. However, the molecular underpinnings of this nutrient dose-response are largely unknown. Dose-responsive gene expression patterns are driven largely by Michaelis–Menten (MM) kinetics, indicating that genome-wide transcriptional responses to nutrient do resemble a simple principle of enzyme kinetics. Transcription factors (TFs) can act as “catalysts” driving rates of transcript change in response to nutrient dose.

How organisms sense and respond to changes in nutrient dose is a basic unanswered question that is relevant to agriculture. A publication by Gloria M. Coruzzi and her colleagues at the Center for Genomics and Systems Biology, New York University, on the study of the molecular mechanisms that underlie N-dose-responsive transcriptome kinetics could lead to enhanced crop growth.

For more, see (it also gives access to the full article)

https://www.pnas.org/content/early/2020/05/14/1918619117/tab-figures-data

Potential Crops/Technologies

1. Cool beans: A vertical crop fit for Africa’s changing climate and nutritional gaps

Growing more climbing beans, as opposed to lower-yielding bush beans, could help increase food security in sub-Saharan Africa as demand for food increases, climate change becomes more pronounced, and arable land becomes scarcer, according to a new study. Researchers of the International Center for Tropical Agriculture (CIAT) have proposing climbing beans as an intensification solution, mostly because they yield three times more than bush beans. Varieties of the common bean, Phaseolus vulgaris, are essential for nutrition and income for millions in sub-Saharan Africa.

Models that have been developed suggest climbing beans can now find suitable hotspots in the Great African Lakes region, and parts of Ethiopia, Cameroon, and Zimbabwe, while Rwanda will become increasingly fit for the crop. Though experts predict that higher temperatures and less rainfall will make many areas inhospitable even for climbing beans, they argue there are still places that will become more suitable for the variety.

Climbing beans might help not only Africa but also other regions growing beans in similar conditions—such as Central America and the Andes, especially with the incorporation of heat- and drought-tolerant varieties.

For more, see https://phys.org/news/2020-03-cool-beans-vertical-crop-africa.html?utm_source=nwletter&utm_medium=email&utm_campaign=daily-nwletter

Access the abstract at https://link.springer.com/article/10.1007/s11027-019-09910-4

2. Cover crops can benefit hot, dry soils

Usually grown during seasons when primary crops are not cultivated, cover crops can include legumes, such as pea and hairy vetch, or grassy crops, like oats and barley. Cover crops do more than just cover fields between growing seasons, including improving soil health. To determine soil health, the researchers from New Mexico State University and the United States Department of Agriculture measured soil carbon dioxide emissions. Soil microbes are tiny creatures that live and breathe in healthy soil. Carbon dioxide is released from soils during plant root and soil microbial respiration. “Soil carbon dioxide release needs to be balanced with soil carbon storage,” says Rajan Ghimire, a researcher at New Mexico State University.

Cover crops increase soil carbon storage in two ways. Although the emissions were higher than in fallow, canola and pea-oat mixed (PO mix) plots had lower CO2–emissions than other cover crops. Pea as a sole cover crop or in mixtures increased CO2–C emissions and microbial activity, whereas the canola and POmix mixture reduced the emissions during the period with higher precipitation. Dr Ghimire described the benefits of cover crops and residue cover to subsequent crops in the rotation and soil health to farmers and local stakeholders. Grassy cover crops, such as oat and barley, contribute well to soil carbon accumulation without the extra emissions from fixing nitrogen.

(Note: Despite the benefits from growing cover crops, the potential of this practice is hardly exploited)

For more, see https://phys.org/news/2020-03-crops-benefit-hot-soils.html?utm_source=nwletter&utm_medium=email&utm_campaign=daily-nwletter

Access the full article at

https://acsess.onlinelibrary.wiley.com/doi/epdf/10.1002/agg2.20012

3. Forests that heal: Medicinal plants as an ecosystem service

Medicinal plants were listed as a provisioning ecosystem service in the United Nations Millennium Ecosystem Assessment of 2005. India has had an ancient history of both codified and non-codified healing systems that use medicinal plants across the subcontinent. Medicinal plants play a crucial role in drug discovery, with at least 25% of modern medicine derived from them, either directly or indirectly. And with global biodiversity loss and erosion of traditional knowledge systems, threats to medicinal plants and their associated knowledge are many. Haridasan, retired joint director of the Foundation for Revitalization of Local Health Traditions (now The University of Trans-Disciplinary Health Sciences and Technology), points out that small taxa such as herbaceous plants, especially in temperate areas, would be some of the first to be affected by climate change.

In the Andaman and Nicobar Islands, four indigenous communities, including the Jarawa, use 39 endemic medicinal plants for their health needs; 17 of these are used to cure multiple ailments, finds a 2018 study. Many researchers have also pointed out that enhanced research on in vitro methods, including the production of secondary metabolites, would be crucial for the conservation and “effective and sustainable use” of these plants. This technology can help in replanting of highly threatened medicinal plants and in avoiding overexploitation of natural populations in the Western Ghats (and elsewhere as well).

A six-hectare medicinal plant park developed with the state government in Jeypore, Odisha, functions as a plant genetic repository and field site for nine tribal communities to cultivate and harvest the medicinal plants they have relied on for centuries. Studies related to climate change and their effect on medicinal plants indicate that many of the species flowers earlier, thus altering their time of harvesting. The effect on secondary metabolites needs to be studied.

For more, see https://india.mongabay.com/2020/02/forests-that-heal-medicinal-plants-as-an-ecosystem-service/

4. How ‘speed breeding’ will help expand crop diversity to feed 10 billion people

With an ever-increasing human population, predicted to be 10 billion people by 2050, studies estimate that we need to double the rate of genetic gain in our crop improvement programs globally to meet this demand. Dr Lee Hickey of the University of Queensland, Australia is a plant breeder and crop geneticist involved in developing speed breeding protocols so far and shares the latest unpublished protocols. He is involved in developing speed-breeding facilities in Asia and Africa to facilitate speed breeding crops for the future to regions of the world that need it the most. He collaborates with the John Innes Centre to assemble the data, information, and details needed to speed breed whatever crop researchers or breeders would like to grow around the world and make protocols for speed breeding available globally.

Genomic selection is the perfect match for speed breeding as genomic selection serves to reduce the breeding time frame by removing the need to do the field testing to identify parents that can be used for the next cycle of breeding. This has revolutionized plant breeding, for instance enabling plant breeders to track genes and even develop predictive breeding approaches, such as genomic selection. While speed breeding technology was originally developed and applied to wheat many years ago, more recently it has been adapted as an approach to a range of important crops. We have published protocols that enable rapid cycling of other long-day and day-neutral crops like barley, canola, and chickpea.

For more, see https://geneticliteracyproject.org/2020/03/02/how-speed-breeding-will-help-us-expand-crop-diversity-to-feed-10-billion-people/

5. Better Plant Screening Could Lead to Faster Innovation

Each year, breeders examine hundreds of thousands of plant genetic lines to try to pinpoint the few that have promise—this takes many hours of time and effort. New research from the University of Illinois has found a way to get around this problem (as published in two separate articles). Previous research suggested that plant breeders needed two expensive hyperspectral cameras to estimate photosynthetic capacity, but this study proved they needed just one. “Hyperspectral cameras are expensive and their data is not accessible to scientists who lack a deep understanding of computational analysis,” said Carl Bernacchi, a research plant physiologist with USDA, Agricultural Research Service (ARS).

“Our results suggest we do not always need ‘high-resolution’ reflectance data to estimate photosynthetic capacity,” said Peng Fu, a Realizing Increased Photosynthetic Efficiency (RIPE) postdoctoral researcher who leads the study’s computational work. The team used 240 bands of reflectance spectra and a radiative transfer model to identify seven important leaf traits from the hyperspectral information. Sometimes knowing where to look is the biggest challenge, and this research helps address that.” Researchers used hyperspectral cameras to find traits related to photosynthesis.

“Through these studies, our team has taken a technology that was out of reach and made it more available to our research community, so that we can unearth traits needed to provide farmers all over the world with higher-yielding crops,” the researchers say.

For more, see https://www.agweb.com/article/better-plant-screening-could-lead-faster-innovation

Access article 1 in full at

https://academic.oup.com/jxb/article/71/7/2312/5754088

Access article 2 in full at

https://onlinelibrary.wiley.com/doi/full/10.1111/pce.13718

News:

1. There is a chance to halt biodiversity loss. The stakes have never been higher

The year 2020 has been designated a “super year for nature” when the global community will rededicate itself to halting biodiversity loss with a 10-year action agenda. The formal agreement toward this is scheduled for the conference of the parties to the UN Convention on Biodiversity (CBD) in Kunming, China, to be held in October, but now in doubt on account of the pandemic. A first draft has been developed, and it was under negotiation at a meeting in Rome during February 2020. From the way various governments reacted, there appears to be an excellent chance to improve the chances of protecting biodiversity.

For more, see

https://www.theguardian.com/environment/2020/feb/24/we-have-a-chance-to-halt-biodiversity-loss-the-stakes-have-never-been-higher-aoe

2. Improved yields in African project areas

Owing to serious socioeconomic and environmental constraints, African smallholder farm yields are among the lowest in the world, some of the reasons being limited access to seeds of good quality, fertilizers, water, information, and markets. The EU-funded InnovAfrica project is currently testing, integrating, and disseminating potential sustainable agriculture intensification systems suitable to smallholders, combined with institutional approaches, and extension and advisory services. Project coordinator Dr Udaya Sekhar Nagothu reports good results from farmer-led field demonstrations of maize-legume/millet-legume and Brachiaria-livestock forage grass systems. The project has reached approximately 60,000 farmers via three selected knowledge exchange systems, i.e. Village Knowledge Centres, Integrated Farm Plan, and Farmer to Farmer Exchange.

For more, see https://phys.org/news/2020-02-yields-african-areas.html?utm_source=nwletter&utm_medium=email&utm_campaign=daily-nwletter

3. How gut bacteria make broccoli a superfood

Scientists reveal the pathway used by one gut microbe to transform vegetable components into anti-cancer compounds. During digestion, gut bacteria transform glucosinolates into compounds called isothiocyanates, which have protective effects against certain cancers. Elizabeth Sattely at Stanford University in California and her colleagues have pinpointed a set of genes that gives the gut microbe Bacteroides thetaiotaomicron the ability to turn glucosinolates into isothiocyanates. When the researchers introduced the genes into bacteria that do not normally help to digest glucosinolates, the microbes began producing isothiocyanates.

For more, see https://www.nature.com/articles/d41586-020-00493-8

4. Wheat tolerance to subsoil acidity and aluminium toxicity

Researchers from The University of Western Australia (UWA), the Commonwealth Scientific and Industrial Research Organisation (CSIRO), and visiting fellows from the Indian Agricultural Research Institute (IARI) and Huazhong Agricultural University, China, are working together to find innovative approaches to improve crop tolerance to subsoil acidity with high aluminium (Al3+) content. Soil acidity is a significant factor limiting grain yield in the West Australian grain belt, with 72% of topsoils and 45% of subsurface soils being acidic.The genes TaALMT1 and TaMATE1B for Al3 tolerance from bread wheat have then introgressed into the durum wheat cultivar Jandaroi, which has been considered as an option for improving the tolerance of durum wheat to acid soils, given the absence of genes for Al3 tolerance in durum germplasm.

For more, see

http://www.ioa.uwa.edu.au/__data/assets/pdf_file/0010/3440089/IOA-December-2019-Newsletter_.pdf

5. SDG Advocates Hold Seed Summit Linking Food Security with Seed Diversity

The co-chairs of the UN Secretary-General’s Group of Advocates for Sustainable Development Goals (SDGs)—Prime Minister Erna Solberg of Norway and President Nana Akufo-Addo of Ghana—held a “Seed Summit” in March 2020. They emphasized the interrelated nature of Sustainable Development Goals (SDGs). The Summit also issued a Call to Action, which urges governments to step up efforts to maintain genetic diversity, “including through soundly managed seed and plant banks.” It encourages genebanks to make use of the Svalbard Global Seed Vault as part of their strategy for securing important seed collections. During the Summit, Kent Nnadozie, Secretary of the FAO International Treaty on Plant Genetic Resources for Food and Agriculture, described the Svalbard Global Seed Vault as “the ultimate insurance policy for the world’s food supply.” It contains the world’s largest global backup collection of seed samples from food and forage crops, representing over 6,000 plant species.

For more, see http://sdg.iisd.org/news/sdg-advocates-hold-seed-summit-linking-food-security-with-seed-diversity/

6. New eggplant varieties resistant to extreme conditions

The Universitat Politècnica de València (UPV), through the Institute of Conservation and Improvement of Valencian Agrodiversity (COMAV), leads EggPreBreed II, an international project that will help in developing new varieties of eggplants more resistant to extreme drought conditions and two of its dreaded pests, Fusarium wilt and nematodes. In the first phase of this project, Jaime Prohens, director of COMAV-UPV and principal investigator of EggPreBreed II, and his team managed to cross domestic varieties of eggplant with 15 different wild relatives. The EggPreBreed-II project also involves an Egyptian university (University of Kafrelsheikh), involved in the analysis of resistance to Fusarium and nematodes, as well as several seed companies from the Philippines, Egypt, France, and Spain, who will all test the commercial utility of the plant materials developed in the project and will incorporate them in their breeding programs to develop new varieties.

This project opens the door to a new generation of commercial varieties of eggplant that can have greater efficiency in the use of water, and with better functional properties. The project is part of the global initiative “Adapting Agriculture to Climate Change: Collecting, Protecting and Preparing Wild Relatives”, led by the Global Crop Diversity Trust (Crop Trust) and funded by the Norwegian Government.

For more, see https://phys.org/news/2020-03-eggplant-varieties-resistant-extreme-conditions.html

Events

1. 14th International Conference on Agriculture and Plant Science: 22-23 Jun 2020, Webinar on The Challenges for Agriculture at the Scenario of COVID-19

https://agriculture.conferenceseries.com/

2. ICABFS 2020: 14th International Conference on Agriculture, Biofuels and Food Security, 17-18 Aug 2020 in Istanbul, Turkey.

https://waset.org/agriculture-biofuels-and-food-security-conference-in-august-2020-in-istanbul

3. AGRICO 2020: 7th International Conference on Agriculture 2020 will be held in Bangkok, Thailand, 26–27 Nov 2020 (new dates).

https://agroconference.com/

Other Topics of Interest

1. Digging Deeper for Agricultural Resources, the Value of Deep Rooting

For more, see https://www.cell.com/trends/plant-science/fulltext/S1360-1385(19)30332-2?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS1360138519303322%3Fshowall%3Dtrue

2. Flowering Plants in the Anthropocene: A Political Agenda

For more, see https://www.cell.com/trends/plant-science/fulltext/S1360-1385(19)30333-4?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS1360138519303334%3Fshowall%3Dtrue

3. New technique that has potential to protect oranges from citrus greening

For more, see https://phys.org/news/2020-03-technique-potential-oranges-citrus-greening.html?utm_source=nwletter&utm_medium=email&utm_campaign=daily%E2%80%A6%201/2

4. ‘Sustainable intensification’ of cropping systems good for farmers, environment

For more, seehttps://phys.org/news/2020-03-sustainable-intensification-cropping-good-farmers.html

5. Long-term analysis shows GM cotton no match for insects in India

For more, see https://phys.org/news/2020-03-long-term-analysis-gm-cotton-insects.html?utm_source=nwletter&utm_medium=email&utm_campaign=daily-nwletter and https://www.nature.com/articles/s41477-020-0615-5

6. New aflatoxin biocontrol product lowers contamination of groundnut and maize in Senegal

For more, see https://phys.org/news/2020-03-aflatoxin-biocontrol-product-lowers-contamination.html Access full article at

https://apsjournals.apsnet.org/doi/10.1094/PDIS-03-19-0575-RE

7. Some domesticated plants ignore beneficial soil microbes

For more, see

https://www.sciencedaily.com/releases/2020/03/200310164748.htm

Access the abstract at https://www.cell.com/trends/ecology-evolution/pdf/S0169-5347(20)30008-2.pdf?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0169534720300082%3Fshowall%3Dtrue

8. Microbes play important role in soil’s nitrogen cycle

For more, see https://phys.org/news/2020-03-microbes-important-role-soil-nitrogen.html?utm_source=nwletter&utm_medium=email&utm_campaign=daily-nwletter

Access the full article at

https://acsess.onlinelibrary.wiley.com/doi/full/10.1002/saj2.20029

9. Photosynthesis varies greatly across rice cultivars—natural diversity could boost yields

For more, see https://phys.org/news/2020-03-photosynthesis-varies-greatly-rice-cultivarsnatural.html?utm_source=nwletter&utm_medium=email&utm_campaign%E2%80%A6%201/6

Access article 1 in full at

https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.16454

Access article 2 in full athttps://science.sciencemag.org/content/354/6314/857

10. Big data helps farmers adapt to climate variability

For more, see https://phys.org/news/2020-02-big-farmers-climate-variability.html?utm_source=nwletter&utm_medium=email&utm_campaign=daily-nwletter

Access the full article at https://www.nature.com/articles/s41598-020-59494-2.pdf

11. Researchers create hybrids of six yeast species to combine useful traits

For more, see https://www.nature.com/articles/s41467-020-15559-4

12. Chickpea’s trick can help mustard fight fungi

For more, see https://researchmatters.in/news/chickpea%E2%80%99s-trick-can-help-mustard-fight-fungi

Access the abstract of the paper at

https://apsjournals.apsnet.org/doi/pdf/10.1094/MPMI-05-19-0117-R

13. With 30,000 surveys, researchers build the go-to dataset for smallholder farms

For more, see https://phys.org/news/2020-03-surveys-go-to-dataset-smallholder-farms.html

14. 20 Benefits from Agricultural Genome Editing

For more, see https://seedworld.com/20-benefits-from-agricultural-genome-editing/

15. Anthropogenic seed dispersal: Rethinking the origins of plant domestication

For more, see

https://www.sciencedaily.com/releases/2020/02/200227114450.htm

Access the full article at https://www.cell.com/action/showPdf?pii=S1360-1385%2820%2930022-4

16. Why the future of agriculture lies in Israel’s desert

For more, see https://www.israel21c.org/why-the-future-of-agriculture-lies-in-israels-desert/

17. How Agtech helps China prepare for spring planting during Coronavirus outbreak

For more, see https://www.futurefarming.com/Smart-farmers/Articles/2020/4/How-agtech-helps-China-prepare-for-spring-planting-during-Coronavirus-outbreak-568417E/

 

AgriTech News Number 16 15 June 2020

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