{"id":12931,"date":"2024-10-28T22:00:00","date_gmt":"2024-10-28T22:00:00","guid":{"rendered":"https:\/\/modernsciences.org\/staging\/4414\/?p=12931"},"modified":"2024-10-07T08:27:25","modified_gmt":"2024-10-07T08:27:25","slug":"trees-own-beneficial-microbiome-could-lead-to-discovery-of-new-treatments-to-fight-citrus-greening-disease","status":"publish","type":"post","link":"https:\/\/modernsciences.org\/staging\/4414\/trees-own-beneficial-microbiome-could-lead-to-discovery-of-new-treatments-to-fight-citrus-greening-disease\/","title":{"rendered":"Trees\u2019 own beneficial microbiome could lead to discovery of new treatments to fight citrus greening disease"},"content":{"rendered":"\n<div class=\"theconversation-article-body\">\n    <figure>\n      <img  decoding=\"async\"  src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEUAAP+KeNJXAAAAAXRSTlMAQObYZgAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAApJREFUCNdjYAAAAAIAAeIhvDMAAAAASUVORK5CYII=\"  class=\" pk-lazyload\"  data-pk-sizes=\"auto\"  data-pk-src=\"https:\/\/images.theconversation.com\/files\/621726\/original\/file-20240925-16-x6e4zn.jpg?ixlib=rb-4.1.0&rect=22%2C13%2C2964%2C1980&q=45&auto=format&w=754&fit=clip\" >\n        <figcaption>\n          Citrus is still big business in Florida, but the industry has taken a massive hit in recent decades.\n          <span class=\"attribution\"><a class=\"source\" href=\"https:\/\/www.gettyimages.com\/detail\/news-photo\/in-an-aerial-view-oranges-are-packed-into-a-transport-truck-news-photo\/1368099292?adppopup=true\" target=\"_blank\" rel=\"noopener\">Joe Raedle\/via Getty Images<\/a><\/span>\n        <\/figcaption>\n    <\/figure>\n\n  <span><a href=\"https:\/\/theconversation.com\/profiles\/kateel-g-shetty-1542183\" target=\"_blank\" rel=\"noopener\">Kateel G. Shetty<\/a>, <em><a href=\"https:\/\/theconversation.com\/institutions\/florida-international-university-729\" target=\"_blank\" rel=\"noopener\">Florida International University<\/a><\/em>; <a href=\"https:\/\/theconversation.com\/profiles\/jessica-dominguez-1542929\" target=\"_blank\" rel=\"noopener\">Jessica Dominguez<\/a>, <em><a href=\"https:\/\/theconversation.com\/institutions\/florida-international-university-729\" target=\"_blank\" rel=\"noopener\">Florida International University<\/a><\/em>, and <a href=\"https:\/\/theconversation.com\/profiles\/krishnaswamy-jayachandran-1477283\" target=\"_blank\" rel=\"noopener\">Krishnaswamy Jayachandran<\/a>, <em><a href=\"https:\/\/theconversation.com\/institutions\/florida-international-university-729\" target=\"_blank\" rel=\"noopener\">Florida International University<\/a><\/em><\/span>\n\n  <p>Citrus trees showing natural tolerance to citrus greening disease host bacteria that produce novel antimicrobials that can be used to fight off the disease, <a href=\"https:\/\/doi.org\/10.3390\/microorganisms11061529\" target=\"_blank\" rel=\"noopener\">our recent study shows<\/a>. We found the trees at an organic farm in Clermont, Florida.<\/p>\n\n<p>Citrus greening disease \u2013 <a href=\"https:\/\/doi.org\/10.1111\/jipb.12437\" target=\"_blank\" rel=\"noopener\">known more formally as Huanglongbing, or HLB<\/a>, is caused by the bacterium <em>Candidatus Liberibacter asiaticus<\/em>. It is spread by <a href=\"https:\/\/www.aphis.usda.gov\/plant-pests-diseases\/citrus-diseases\/citrus-greening-and-asian-citrus-psyllid\" target=\"_blank\" rel=\"noopener\">an insect called the Asian citrus psyllid<\/a>. There is no known cure for the disease.<\/p>\n\n<p>We are <a href=\"https:\/\/scholar.google.com\/scholar?hl=en&as_sdt=0%2C22&q=Kateel+G.+Shetty&btnG=\" target=\"_blank\" rel=\"noopener\">Florida-based researchers<\/a> who study <a href=\"https:\/\/scholar.google.com\/scholar?hl=en&as_sdt=0%2C22&q=Krishnaswamy+Jayachandran&btnG=\" target=\"_blank\" rel=\"noopener\">sustainable farming practices<\/a>, <a href=\"https:\/\/case.fiu.edu\/earth-environment\/agroecology\/degrees-programs\/students\/\" target=\"_blank\" rel=\"noopener\">a discipline also known as agroecology<\/a>. Our team has isolated these antimicrobial compounds in the lab and is now working to test them with the goal of producing an effective treatment for HLB.<\/p>\n\n<h2 id=\"why-it-matters\">Why it matters<\/h2>\n\n<p>HLB has dealt a massive blow to Florida\u2019s iconic citrus industry.<\/p>\n\n<p>Since <a href=\"https:\/\/www.sierraclub.org\/sierra\/florida-citrus-loses-its-sweet-taste-scientists-are-hunt-solutions\" target=\"_blank\" rel=\"noopener\">citrus greening disease<\/a> was first detected in the state in 2005, Florida <a href=\"https:\/\/citrusindustry.net\/2024\/05\/07\/florida-orange-production-plummeted-years\/\" target=\"_blank\" rel=\"noopener\">citrus production is down by more than 92%<\/a>. The disease is just one factor. Others include hurricanes and freezes.<\/p>\n\n<p><a href=\"https:\/\/www.aphis.usda.gov\/plant-pests-diseases\/citrus-diseases\/citrus-greening-and-asian-citrus-psyllid\" target=\"_blank\" rel=\"noopener\">Infected trees<\/a> produce fewer fruit. The fruit that does grow is partially green, smaller, shaped irregularly and bitter tasting. It may drop from the trees before ripening. Leaves may show blotchy mottling.<\/p>\n\n<p>According to the U.S. Department of Agriculture, the 2022-2023 growing season was <a href=\"https:\/\/www.wqcs.org\/wqcs-news\/2023-07-17\/usda-issues-final-citrus-estimate-worst-crop-since-1936\" target=\"_blank\" rel=\"noopener\">the least productive since 1936<\/a>. Smaller crops lead to higher prices on oranges, tangerines, grapefruits, lemons and limes.<\/p>\n\n<figure class=\"align-left zoomable\">\n            <a href=\"https:\/\/images.theconversation.com\/files\/622850\/original\/file-20241001-18-lms7q6.png?ixlib=rb-4.1.0&q=45&auto=format&w=1000&fit=clip\" target=\"_blank\" rel=\"noopener\"><img  decoding=\"async\"  alt=\"A few pale lemons growing in spotted foliage\"  src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEUAAP+KeNJXAAAAAXRSTlMAQObYZgAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAApJREFUCNdjYAAAAAIAAeIhvDMAAAAASUVORK5CYII=\"  class=\" pk-lazyload\"  data-pk-sizes=\"auto\"  data-ls-sizes=\"(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px\"  data-pk-src=\"https:\/\/images.theconversation.com\/files\/622850\/original\/file-20241001-18-lms7q6.png?ixlib=rb-4.1.0&q=45&auto=format&w=237&fit=clip\"  data-pk-srcset=\"https:\/\/images.theconversation.com\/files\/622850\/original\/file-20241001-18-lms7q6.png?ixlib=rb-4.1.0&q=45&auto=format&w=600&h=652&fit=crop&dpr=1 600w, https:\/\/images.theconversation.com\/files\/622850\/original\/file-20241001-18-lms7q6.png?ixlib=rb-4.1.0&q=30&auto=format&w=600&h=652&fit=crop&dpr=2 1200w, https:\/\/images.theconversation.com\/files\/622850\/original\/file-20241001-18-lms7q6.png?ixlib=rb-4.1.0&q=15&auto=format&w=600&h=652&fit=crop&dpr=3 1800w, https:\/\/images.theconversation.com\/files\/622850\/original\/file-20241001-18-lms7q6.png?ixlib=rb-4.1.0&q=45&auto=format&w=754&h=819&fit=crop&dpr=1 754w, https:\/\/images.theconversation.com\/files\/622850\/original\/file-20241001-18-lms7q6.png?ixlib=rb-4.1.0&q=30&auto=format&w=754&h=819&fit=crop&dpr=2 1508w, https:\/\/images.theconversation.com\/files\/622850\/original\/file-20241001-18-lms7q6.png?ixlib=rb-4.1.0&q=15&auto=format&w=754&h=819&fit=crop&dpr=3 2262w\" ><\/a>\n            <figcaption>\n              <span class=\"caption\">Pomelo tree leaves with symptoms of citrus greening.<\/span>\n              <span class=\"attribution\"><span class=\"source\">Conor Wolfe<\/span>, <a class=\"license\" href=\"http:\/\/creativecommons.org\/licenses\/by-nd\/4.0\/\" target=\"_blank\" rel=\"noopener\">CC BY-ND<\/a><\/span>\n            <\/figcaption>\n          <\/figure>\n\n<p>Management of HLB is daunting. Growers currently <a href=\"https:\/\/ipm.ucanr.edu\/agriculture\/citrus\/asian-citrus-psyllid\/#gsc.tab=0\" target=\"_blank\" rel=\"noopener\">rely on pesticides<\/a> to control the psyllid and <a href=\"https:\/\/crec.ifas.ufl.edu\/media\/crecifasufledu\/extension\/extension-publications\/2023\/2023_october_oxytetracycline.pdf\" target=\"_blank\" rel=\"noopener\">antibiotics like oxytetracycline<\/a> in an attempt to control HLB. These treatments are expensive and <a href=\"http:\/\/dx.doi.org\/10.3390\/molecules23040795\" target=\"_blank\" rel=\"noopener\">may pose health<\/a> and <a href=\"http:\/\/dx.doi.org\/10.2478\/v10102-009-0001-7\" target=\"_blank\" rel=\"noopener\">environmental risks<\/a>. The need for development of effective treatments to control HLB is evident.<\/p>\n\n<h2 id=\"how-we-did-our-work\">How we did our work<\/h2>\n\n<p>Like humans, <a href=\"https:\/\/www.energy.gov\/science\/doe-explainsthe-plant-microbiome\" target=\"_blank\" rel=\"noopener\">plants host diverse communities of microorganisms<\/a> both inside and outside, representing the plant microbiome.<\/p>\n\n<p><a href=\"https:\/\/doi.org\/10.1007\/978-3-319-66541-2\" target=\"_blank\" rel=\"noopener\">Endophytes \u2013 beneficial microorganisms<\/a> living inside plants \u2013 <a href=\"https:\/\/www.mdpi.com\/2076-2607\/11\/5\/1276\" target=\"_blank\" rel=\"noopener\">play an important role<\/a> in nutrient intake, disease and pest resistance, and adaptation to environmental stress.<\/p>\n\n<p>In a search for treatments against HLB, we looked to endophytes of survivor citrus trees \u2013 in other words, trees that are HLB positive but showed only mild symptoms and continue to bear fruit. By studying 342 endophytes of survivor trees, we discovered five bacterial endophytes capable of producing novel antimicrobials.<\/p>\n\n<p>The HLB bacteria cannot be grown on <a href=\"https:\/\/science.umd.edu\/classroom\/bsci424\/LabMaterialsMethods\/MediaTypes.htm\" target=\"_blank\" rel=\"noopener\">laboratory culture media<\/a> like agar or broth. So, we used live bacterial cells present in the ground tissue samples of infected psyllids to test the antimicrobial compounds in the lab. These studies revealed that the antimicrobial compounds were <a href=\"https:\/\/www.mdpi.com\/2076-2607\/11\/6\/1529\" target=\"_blank\" rel=\"noopener\">highly effective at killing the live cells<\/a> of citrus greening pathogen in <a href=\"https:\/\/doi.org\/10.1186\/s13007-019-0465-1\" target=\"_blank\" rel=\"noopener\">this controlled environment<\/a>. The antimicrobials can be mixed with water and were found to be effective at low concentrations.<\/p>\n\n<h2 id=\"whats-still-not-known\">What\u2019s still not known<\/h2>\n\n<p>Preliminary results from our ongoing work indicate that multiple antimicrobial compounds are present in the bacterial culture extract. This is a positive sign because the antimicrobial compounds may be found to attack pathogenic bacteria in several different ways. If that\u2019s the case, it will help minimize the development of resistance in the same way a variety of antibiotics are useful to human doctors.<\/p>\n\n<p>One of our next steps will be to evaluate selected compounds against HLB, using infected citrus roots under laboratory conditions and infected citrus plants under greenhouse conditions, to test whether the plants will absorb these antimicrobial compounds through their leaves or roots. This work will be conducted in collaboration with scientists from Texas A&M University and the University of Florida.<\/p>\n\n<h2 id=\"whats-next\">What\u2019s next<\/h2>\n\n<p>Further research will focus on methods to increase the production of purified antimicrobial compound in order for it to be evaluated in the field. To help get the technology to growers faster, we may look for partnerships with interested commercial biopesticide companies to help with product development.<\/p>\n\n<p>Our work has taken on new urgency due to emerging psyllid-transmitted diseases that infect <a href=\"https:\/\/www.ars.usda.gov\/research\/publications\/publication\/?seqNo115=255046\" target=\"_blank\" rel=\"noopener\">potato, tomato and carrot crops<\/a> in the U.S. that are caused by closely related bacterial pathogens.<\/p>\n\n<p><em>The <a href=\"https:\/\/theconversation.com\/us\/topics\/research-brief-83231\" target=\"_blank\" rel=\"noopener\">Research Brief<\/a> is a short take on interesting academic work.<\/em><!-- Below is The Conversation's page counter tag. Please DO NOT REMOVE. --><img  loading=\"lazy\"  decoding=\"async\"  src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEUAAP+KeNJXAAAAAXRSTlMAQObYZgAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAApJREFUCNdjYAAAAAIAAeIhvDMAAAAASUVORK5CYII=\"  alt=\"The Conversation\"  width=\"1\"  height=\"1\"  style=\"border: none !important; box-shadow: none !important; margin: 0 !important; max-height: 1px !important; max-width: 1px !important; min-height: 1px !important; min-width: 1px !important; opacity: 0 !important; outline: none !important; padding: 0 !important\"  referrerpolicy=\"no-referrer-when-downgrade\"  class=\" pk-lazyload\"  data-pk-sizes=\"auto\"  data-pk-src=\"https:\/\/counter.theconversation.com\/content\/232681\/count.gif?distributor=republish-lightbox-basic\" ><!-- End of code. If you don't see any code above, please get new code from the Advanced tab after you click the republish button. The page counter does not collect any personal data. More info: https:\/\/theconversation.com\/republishing-guidelines --><\/p>\n\n  <p><span><a href=\"https:\/\/theconversation.com\/profiles\/kateel-g-shetty-1542183\" target=\"_blank\" rel=\"noopener\">Kateel G. Shetty<\/a>, Assistant Professor of Earth and Environment, <em><a href=\"https:\/\/theconversation.com\/institutions\/florida-international-university-729\" target=\"_blank\" rel=\"noopener\">Florida International University<\/a><\/em>; <a href=\"https:\/\/theconversation.com\/profiles\/jessica-dominguez-1542929\" target=\"_blank\" rel=\"noopener\">Jessica Dominguez<\/a>, PhD Candidate in Agroecology, <em><a href=\"https:\/\/theconversation.com\/institutions\/florida-international-university-729\" target=\"_blank\" rel=\"noopener\">Florida International University<\/a><\/em>, and <a href=\"https:\/\/theconversation.com\/profiles\/krishnaswamy-jayachandran-1477283\" target=\"_blank\" rel=\"noopener\">Krishnaswamy Jayachandran<\/a>, Professor of Agroecology, <em><a href=\"https:\/\/theconversation.com\/institutions\/florida-international-university-729\" target=\"_blank\" rel=\"noopener\">Florida International University<\/a><\/em><\/span><\/p>\n\n  <p>This article is republished from <a href=\"https:\/\/theconversation.com\" target=\"_blank\" rel=\"noopener\">The Conversation<\/a> under a Creative Commons license. Read the <a href=\"https:\/\/theconversation.com\/trees-own-beneficial-microbiome-could-lead-to-discovery-of-new-treatments-to-fight-citrus-greening-disease-232681\" target=\"_blank\" rel=\"noopener\">original article<\/a>.<\/p>\n<\/div>\n\n","protected":false},"excerpt":{"rendered":"Citrus is still big business in Florida, but the industry has taken a massive hit in recent decades.&hellip;\n","protected":false},"author":983,"featured_media":12933,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"nf_dc_page":"","fifu_image_url":"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/6\/64\/Sunlight_Through_The_Jungle_Trees.jpg\/2560px-Sunlight_Through_The_Jungle_Trees.jpg","fifu_image_alt":"","footnotes":""},"categories":[11],"tags":[1864,810,1865,474],"class_list":{"0":"post-12931","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-nature","8":"tag-citrus","9":"tag-forest","10":"tag-microbiome","11":"tag-the-conversation","12":"cs-entry","13":"cs-video-wrap"},"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/posts\/12931","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/users\/983"}],"replies":[{"embeddable":true,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/comments?post=12931"}],"version-history":[{"count":1,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/posts\/12931\/revisions"}],"predecessor-version":[{"id":12932,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/posts\/12931\/revisions\/12932"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/media\/12933"}],"wp:attachment":[{"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/media?parent=12931"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/categories?post=12931"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/tags?post=12931"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}