{"id":46,"date":"2019-03-12T15:33:59","date_gmt":"2019-03-12T15:33:59","guid":{"rendered":"http:\/\/www.plantagbiosciences.org\/people\/lorene-lefebvre\/?page_id=46"},"modified":"2019-05-12T19:41:14","modified_gmt":"2019-05-12T19:41:14","slug":"nitrogen-use-efficiency-in-colombia-research-blog","status":"publish","type":"page","link":"https:\/\/www.plantagbiosciences.org\/people\/lorene-lefebvre\/","title":{"rendered":"Brachiaria, the future of climate-smart cattle farming in the tropics?"},"content":{"rendered":"\n<figure class=\"wp-block-embed-twitter wp-block-embed is-type-rich is-provider-twitter\"><div class=\"wp-block-embed__wrapper\">\n<blockquote class=\"twitter-tweet\" data-width=\"474\" data-dnt=\"true\"><p lang=\"en\" dir=\"ltr\">One way to reduce cattle farming\u2019s negative environmental impacts is by using improved grasses which also make farms more profitable. A new genetic breakthrough on grasses may help: <a href=\"https:\/\/t.co\/1m575gYLa0\">https:\/\/t.co\/1m575gYLa0<\/a> <a href=\"https:\/\/twitter.com\/Livestock_CGIAR?ref_src=twsrc%5Etfw\">@Livestock_CGIAR<\/a> <a href=\"https:\/\/twitter.com\/BMZ_Bund?ref_src=twsrc%5Etfw\">@BMZ_Bund<\/a> <a href=\"https:\/\/twitter.com\/giz_gmbh?ref_src=twsrc%5Etfw\">@giz_gmbh<\/a> <a href=\"https:\/\/twitter.com\/Yale?ref_src=twsrc%5Etfw\">@Yale<\/a> <a href=\"https:\/\/twitter.com\/Jacobo_CIAT?ref_src=twsrc%5Etfw\">@Jacobo_CIAT<\/a> <a href=\"https:\/\/twitter.com\/UAFruitBreeding?ref_src=twsrc%5Etfw\">@UAFruitBreeding<\/a> <a href=\"https:\/\/t.co\/FJw7bZyfS0\">pic.twitter.com\/FJw7bZyfS0<\/a><\/p>&mdash; Alianza de Bioversity International y el CIAT (@BiovIntCIAT_esp) <a href=\"https:\/\/twitter.com\/BiovIntCIAT_esp\/status\/1116388008742223873?ref_src=twsrc%5Etfw\">April 11, 2019<\/a><\/blockquote><script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script>\n<\/div><figcaption><br><\/figcaption><\/figure>\n\n\n\n<h4 class=\"wp-block-heading\"> <br>An introduction to my MScCCAFS Research Project: <\/h4>\n\n\n\n<p style=\"text-align:center\"><em>Advancing molecular understanding of Biological Nitrification Inhibition (BNI) for more climate smart agricultural systems.\ufeff<\/em><\/p>\n\n\n\n<p style=\"text-align:left\">For my Climate Change, Agriculture\nand Food Security (CCAFS) Masters\u2019 thesis I have the opportunity to go to\nColumbia and work with CIAT (the International Center for Tropical Agriculture)\non a very interesting subject: Biological Nitrification Inhibition (BNI).<\/p>\n\n\n\n<p style=\"text-align:left\">At the broadest level, this project\ninvolves the intersection of a number of themes relevant to CCAFS: the importance\nof soil microorganisms, greenhouse gas emissions from agriculture, livestock\nmanagement practices, plant physiology. Before elaborating on the concept of BNI\nand its potential for climate change mitigation, it is important to understand the\nprocess of nitrification and its impact on the environment.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">The nitrification process and impacts in short:<\/h4>\n\n\n\n<p>The nitrification process involves different actors, including bacteria and archea which convert nitrogen into different forms  <br> (see figure below). The chemical form of nitrogen determines how the compound is utilized, absorbed by plant roots or dispersed. In managed ecosystems, almost 70% of the applied nitrogen fertilizer is lost through nitrification or associated processes (Glass, 2003; Raun &amp; Johnson, 1999). Nitrogen losses have significant impacts on the environment as it can result in nitric oxide (NO) and nitrous oxide (N2O) emissions or the leaching of nitrate (NO3)- in water.<\/p>\n\n\n\n<p>Nitrous oxide gas is a powerful greenhouse gas that contributes to the global warming effect. NO is a reactive molecule which can take part in reactions that can destroy the ozone layer or contribute to acidification and eutrophication of ecosystems through the formation of acid rain. Nitrate leaching into freshwater bodies or groundwater can also lead to eutrophication and presents a health risk if consumed by human or animals (Giles, 2005).  <\/p>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"754\" height=\"573\" src=\"https:\/\/www.plantagbiosciences.org\/people\/lorene-lefebvre\/wp-content\/uploads\/sites\/81\/2019\/05\/n-cycle.jpg\" alt=\"\" class=\"wp-image-141\" srcset=\"https:\/\/www.plantagbiosciences.org\/people\/lorene-lefebvre\/wp-content\/uploads\/sites\/81\/2019\/05\/n-cycle.jpg 754w, https:\/\/www.plantagbiosciences.org\/people\/lorene-lefebvre\/wp-content\/uploads\/sites\/81\/2019\/05\/n-cycle-300x228.jpg 300w\" sizes=\"auto, (max-width: 754px) 100vw, 754px\" \/><figcaption>The biological and physical processes that make up the nitrogen cycle.\u00a0 KoiQuestion, CC BY-SA <\/figcaption><\/figure>\n\n\n\n<p>This nitrogen loss is not only a major concern for environment but also increases inefficiency of N-fertilizer use and thus constitutes an economic loss for farmers (Coskun, Britto, Shi, &amp; Kronzucker, 2017; Subbarao, Wang, Ito, Nakahara, &amp; Berry, 2007).<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">A quick history of the discovery of BNI:<\/h4>\n\n\n\n<p>An early report by Russel in 1914\nindicated that some field crops could influence nitrification and nitrate\nformation in soils. Later on, in 1951, another scientist suspected the\nexistence of BNI. This scientist, Theron, suggested that some tropical grass\nroots were excreting substances that were toxic to nitrifying bacteria (Theron, 1951). In the following decades, several scientists\nsupported that hypothesis, however the lack of proof of the direct effect of\nBNI hindered support from the scientific community (Moore &amp; Waid, 1971; Rice, 1964). Finally, in 2006, a bioassay\nproved the direct inhibition of the nitrifying enzymatic pathways in <em>Nitrosomas <\/em>by the BNI activity of<em> Brachiaria humidicola <\/em>(Subbarao et al., 2006)<em>.<\/em><\/p>\n\n\n\n<p>With the search for a sustainable,\necologically friendly and cost-effective solution to reduce the N loss from\nagricultural systems, studies of the regulation of nitrogen soil dynamics have\nincreased and knowledge about BNI process and potential in crops has improved. Plants\nwith the BNI trait release nitrification inhibitors which reduce or inhibit the\nnitrification of ammonia by nitrifier microorganisms. This not only limits potential\nnitrogen loss from agricultural systems but also keeps nitrogen in the soil;\nimproving nitrogen recovery and uptake by the plants (Subbarao et al., 2006). <\/p>\n\n\n\n<h4 class=\"wp-block-heading\"><em>Brachiaria humidicola: <\/em>a model plant for BNI<\/h4>\n\n\n\n<p>The major plant model for\nstudying BNI in recent years has been <em>Brachiaria\nhumidicola<\/em>, an important forage grass in tropical agricultural systems. CIAT\npossess a gene bank containing 601 accessions of <em>Brachiaria<\/em> <em>spp.<\/em> containing\nimportant agronomical traits such as the ability to grow on infertile soil or resistance\nto drought, that have been exploited in breeding programs (Keller-Grein, Maass, &amp; Hanson, 1996). This, and their expertise in\nthe topic of BNI, make CIAT an excellent place to study the mechanisms of BNI\nfurther.<\/p>\n\n\n\n<p>The potential of <em>Brachiaria<\/em> for BNI could be promising in\nthe pursuit of exploiting this trait to build climate smart agricultural\nsystems. However, the BNI process must be better understood for its potential\nas a mitigation option in agricultural systems to be realised. The core\nmechanism of BNI is to inhibit the ammonia nitrification of surrounding\nnitrifiers, however we need to learn more about the influence of BNI on\nmicrobial communities.<\/p>\n\n\n\n<p>My goal during the three next months is to advance the understanding of the effect of BNI on nitrifiers\u2019 activity and community. Nitrifier community can be assessed by the present of genes contributing to denitrification in soil samples taken in <em>Brachiaria humidicola<\/em> fields, while the nitrifiers\u2019 activity can be measured trough the expression of those genes within similar soil sample in comparison with samples taken where no specific BNI activity is known to be present. As of now, I have arrived at CIAT and have begun to devise a methodology to maximise the potential outcomes of my experiments. <\/p>\n","protected":false},"excerpt":{"rendered":"<p>An introduction to my MScCCAFS Research Project: Advancing molecular understanding of Biological Nitrification Inhibition (BNI) for more climate smart agricultural systems.\ufeff For my Climate Change, Agriculture and Food Security (CCAFS) Masters\u2019 thesis I have the opportunity to go to Columbia and work with CIAT (the International Center for Tropical Agriculture) on a very interesting subject: &hellip; <a href=\"https:\/\/www.plantagbiosciences.org\/people\/lorene-lefebvre\/\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">Brachiaria, the future of climate-smart cattle farming in the tropics?<\/span> <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":83,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-46","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.plantagbiosciences.org\/people\/lorene-lefebvre\/wp-json\/wp\/v2\/pages\/46","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.plantagbiosciences.org\/people\/lorene-lefebvre\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.plantagbiosciences.org\/people\/lorene-lefebvre\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.plantagbiosciences.org\/people\/lorene-lefebvre\/wp-json\/wp\/v2\/users\/83"}],"replies":[{"embeddable":true,"href":"https:\/\/www.plantagbiosciences.org\/people\/lorene-lefebvre\/wp-json\/wp\/v2\/comments?post=46"}],"version-history":[{"count":5,"href":"https:\/\/www.plantagbiosciences.org\/people\/lorene-lefebvre\/wp-json\/wp\/v2\/pages\/46\/revisions"}],"predecessor-version":[{"id":142,"href":"https:\/\/www.plantagbiosciences.org\/people\/lorene-lefebvre\/wp-json\/wp\/v2\/pages\/46\/revisions\/142"}],"wp:attachment":[{"href":"https:\/\/www.plantagbiosciences.org\/people\/lorene-lefebvre\/wp-json\/wp\/v2\/media?parent=46"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}