A newly published study led by researchers from the University of Georgia and several partner institutions reveals a discovery that could lead to new control strategies for a tiny-but-persistent agricultural pest that causes enormous soybean losses.Microscopic soybean cyst nematodes (SCN) Iive in soil and are attracted to the root systems of soybeans. Once a field is infested, it is nearly impossible to root them out, said lead study investigator Melissa Mitchum, professor of plant nematology in UGA’s Department of Plant Pathology and Institute of Plant Breeding, Genetics and Genomics (IPBGG) in the College of Agricultural and Environmental Sciences and Center for Applied Genetic Technologies.Invisible to the naked eye, SCN have unique hollow, protrudable mouth spears — called stylets — that they use to pierce through the root of a plant, injecting peptide effectors, which mimic the soybean’s naturally present CLAVATA3/embryo surrounding region (CLE) peptides to hijack the plant.After hatching from an egg in the soil, the juvenile nematode migrates into the root, where it sets up a feeding site and makes its way toward the circulatory system that the plant uses to transport nutrients to the rest of the plant.Once a root cell is chosen for feeding, the nematodes transform it into a syncytium, a mass comprised of hundreds of metabolically active cells that continue to secrete CLE, taking over the plant’s natural cellular processes to export the peptides back out of the cell to function as external signaling molecules to distant cells.This process diverts resources away from the plant in support of the nutrient demands of the developing nematode. At this point, nematodes change their morphology, turning from wormlike forms into sedentary, lemon-shaped bodies that pop out of the roots, becoming visible to the eye.Study resultsUsing knowledge that has been developed over the past two decades on how nematode CLEs function, the study, published in the journal New Phytologist, uncovered a new pathway that allows the nematode to disrupt the plant’s natural growth processes to divert resources for its own benefit. The study was also highlighted in commentary by the editors of New Phytologist. “We’ve discovered that early on, when the nematode delivers the CLE peptide to a root cell, the peptide has to reach a plant receptor that binds it so that you get a response in the plant. We knew that the nematode delivered the peptide into the cytoplasm of the cell, but the receptor is on the outside of the cell,” Mitchum said.The study shows that the nematode CLEs provide a way for the nematode peptide to get outside of the cell to interact with the plant protein receptor through the plant’s secretion system, a process that is not well-studied in plants.“To me it is fascinating because the nematodes have discovered how to co-opt that part of the plant — its own secretion system — but we don’t understand the secretion system they are taking advantage of,” Mitchum said. “If we can understand how they are doing it, we will likely uncover some novel aspect of plant biology that could have importance to other plant pathosystems. This effector protein is helping us understand plant biology, not just plant pathology.”Normally occurring plant CLE peptides regulate aspects of cell differentiation in the plant, communicating to the plant’s stem cells, which are constantly regenerating, whether to develop into a root cell, a leaf cell or a cell in another part of the plant.“The peptides in the plant — and there are many types — tell the plant how to regulate its growth and development. These nematodes have found a way to trick the plant by secreting these similar peptides in the root cell to make a feeding site,” Mitchum said. “Now we want to determine how the nematode CLE peptide forms that feeding site. That is why it is such a successful parasite — it has evolved this peptide that looks like and functions like a plant peptide, so they can put it into the root cell where it does not normally occur and trick the plant into supporting the formation of a feeding cell for the nematode.”Developing new control strategiesThe next step is to find novel methods to block the nematode peptides from getting out of the feeding cells.“We are trying to figure out how these nematode peptides function because we want to devise a way to interfere with that ability. If we can block the nematode peptides from getting out of the feeding cells, they will not form properly, and the nematode loses its nutrient source and dies,” Mitchum said. “If we can stop the nematodes from making those peptides or keep them from interfering with the processes in the cell, we can engineer different methods of resistance. That is why we study at this detailed level.”Soybean cyst nematodes are the No. 1 yield-reducing pest of soybean producers, robbing seemingly healthy fields of up to 30% of their yields — and costing the industry up to $1 billion every year.The primary management practice for soybean cyst nematodes is through developing genetic resistance in soybean varieties. Because SCN has a specialized host range, producers can control nematode damage by rotating fields to a non-host crop plant to reduce the population of nematodes in the field. However, the bodies of dead female nematodes form a cyst around them, protecting hundreds of eggs. These cysts can remain in the ground for years, protecting the eggs until a host crop is planted again and the nematodes reemerge.A troubling trendWhile creating genetically resistant crops is a very effective tool, SCN have adapted to overcome the source of resistance in the commonly used breeding line PI 88788, which is used in more than 90% of resistant varieties currently planted by producers. As a result, yields in resistant varieties can be reduced by up to 14 bushels per acre, according to The SCN Coalition, a public/private partnership of university researchers, national extension specialists and agriculture company representatives who are concerned about the evolving threat from soybean cyst nematodes.“We need to bring awareness to the increased resistance of SCN to the (PI 88788) resistance and come up with novel approaches to combat it. Targeting the mechanism we have found in this study would be a novel way of addressing this resistance,” she said.Because the symptoms of SCN infestation are often not visible above ground, it is difficult to communicate the severity of the problem to producers and the importance of basic science research to combat it.“If farmers are repeatedly planting the same resistant varieties, which most of them are, and they don’t realize what is going on below ground, the nematodes eventually become resistant to the resistant varieties. Over the past 20 to 30 years, soybean cyst nematodes have shifted from being unable to reproduce in these varieties to nematode populations that are highly aggressive and population densities are going up,” Mitchum said. “The only way growers can know they have a problem is to send in a soil sample to a diagnostic lab. This usually only occurs if they see aboveground symptoms and want to know if they have an issue, but these nematodes can be causing yield loss in the absence of any aboveground symptoms.”Mitchum says there are multiple potential targets to engineer new SCN resistance through the pathway they’ve discovered. Consequently, Mitchum and colleagues have filed several patents related to the research described in this study.“In order to disrupt this target, we can modify the receptor in the plant to retain its function in plant growth and development, but so it does not recognize nematode CLEs; we can try to block the ability of the nematode peptide to be trafficked through the plant’s secretion system; or we can prevent the nematode from making and secreting CLEs,” she said. “There are multiple ways to engineer resistance through this one pathway. If we can knock out a receptor, we can reduce infection, but because the nematode is co-opting a normal growth and development pathway, we have to do it in a way that is not disrupting plant development. This is a highly evolved interaction and we have to be able to understand it to precisely tweak it. We have to do it in a very targeted and specific way.”Assessing the threatBecause soybean cyst nematodes are such a widespread pest, Mitchum and UGA Extension plant pathologist Bob Kemerait, with the help of county agents, will launch a statewide survey in 2021 of all soybean producing counties in Georgia to determine current SCN levels and whether SCN-resistant crops are suffering greater losses due to the nematode’s adaptations against resistant varieties.While Georgia is not a major producer of soybeans — with 100,000 acres planted in 2019 at a value of about $240,000— more than 80 million acres were planted nationwide in 2019, with a production value of $31.2 billion, according to the U.S. Department of Agriculture’s National Agriculture Statistics Service.“From a genetic standpoint, we are working with soybean breeders to diversify the germplasm and working with companies to get new SCN-resistant varieties out to producers while, in parallel, we are doing this kind of basic science research to understand the mechanisms used by the nematode to cause disease so we can interfere with them in a novel way,” Mitchum said.Zeroing in on the scienceBringing awareness to the importance of basic science and basic research is a message that needs to come through when discoveries like this are made, Mitchum said.“A lot of times the return on research investment is not as immediate or apparent as it is if you go out and do a field trial and get immediate results,” Mitchum said. “There has to be a balance — we need to invest in research that will have an immediate impact, but if we are going to come up with breakthrough technologies, it is going to be from an investment in this kind of long-term research.”Lead study author Jianying Wang was a former research associate in Mitchum’s lab. Research partners in the multi-institutional study included Richard S. Hussey, Emeritus Distinguished Research Professor of Nematology at CAES; and CAGT postdoctoral researcher Xunliang Liu; as well as colleagues from University of Missouri, Worcester Polytechnic Institute, Iowa State University, North Carolina State University and Cornell University. Mitchum joined UGA in 2019 from University of Missouri’s Division of Plant Sciences and Bond Life Sciences Center.Funding for this work was from the National Science Foundation and the USDA National Institute of Food and Agriculture’s Agriculture and Food Research Initiative.For more information on research being performed at CAES, visit caes.uga.edu/research.
Twenty percent of the survey’s respondents also said they had tried online grocery shopping for the first time in March.“Online sales of fast-moving consumer goods are usually low, but more people tried it. I think it can be the new normal to buy groceries online,” Lamba added.The survey also showed that 18 percent of respondents also reported doing sports or fitness activities more during the quarantine, while 13 percent of respondents said they tried an online fitness class for the first time during quarantine.“This is a good opportunity for fitness service providers to tap into online classes or to further promote their online products,” Lamba said.Consumers in Indonesia are reporting doing more handwashing and more fitness activities as the COVID-19 pandemic continues to spread. (Mobile Marketing Association (MMA) and SurveySensum/-)A consumer shift toward a more hygienic and healthier lifestyle is concurrent with Google Trend’s data, which show an upward trend in searches for the “immunity” keyword since early March after the President announced the first two cases of COVID-19 in Indonesia.As people try to stay active and healthy to maintain good immunity, they are also staying indoors to comply with the government’s call for physical distancing. The survey also reported that weekend traveling had declined by 77 percent in March, while going to malls for leisure and watching movies in cinemas was down by 76 and 65 percent, respectively.The MMA questioned 500 people in five major cities across Indonesia from March 20 to 21 for the consumer survey while it is also monitoring 80 business to business respondents for the business sentiment survey. Topics : “In the first week after COVID-19 spread to Indonesia, we saw people stocking up. But now we are not seeing that as much,” said SurveySensum founder and CEO Rajiv Lamba at a webinar on Friday.People are buying products from markets in bigger packages as they continue to stay at home more, Lamba said, in line with retailers’ report of a shift in consumer behavior to buy in bulk.The survey findings were also in line with retailers’ report of an uptick in demand for hygiene products as Indonesia declared a public health emergency over COVID-19 on March 31, imposing large-scale social restrictions. COVID-19 cases in Indonesia soared within a month from zero to 2,273 cases with 198 dead, among the highest death rates in the world.Read also: Staple foods safe, but masks, sanitizer gone from markets as consumer behavior shifts A consumer survey in Indonesia has shown that people are buying more health and hygiene products and trying online fitness classes as the coronavirus continues to spread.In the survey, conducted recently by Mobile Marketing Association (MMA) and SurveySensum, 85 percent of respondents reported doing more handwashing while 46 percent said they took vitamin supplements.The survey is backed by data from Nielsen showing that the value of liquid hand soap, for example, saw a 285 percent increase in March compared to the first two months of 2020. People are also buying more hand sanitizer, liquid antiseptic and wet tissues.
Tom Brady most dominant player in AFC championship history Japeth Aguilar wins 1st PBA Finals MVP award for Ginebra Ginebra beats Meralco again to capture PBA Governors’ Cup title MOST READ LATEST STORIES Carpio hits red carpet treatment for China Coast Guard PLAY LIST 02:14Carpio hits red carpet treatment for China Coast Guard02:56NCRPO pledges to donate P3.5 million to victims of Taal eruption00:56Heavy rain brings some relief in Australia02:37Calm moments allow Taal folks some respite03:23Negosyo sa Tagaytay City, bagsak sa pag-aalboroto ng Bulkang Taal01:13Christian Standhardinger wins PBA Best Player award Sports Related Videospowered by AdSparcRead Next Aiming higher Will you be the first P16 Billion Powerball jackpot winner from the Philippines? In fight vs corruption, Duterte now points to Ayala, MVP companies as ‘big fish’ Philippine Army to acquire MANPADS, self-propelled howitzers Golden State Warriors forward Kevin Durant, left, helps escort coach Steve Kerr after Kerr was ejected during the second half of the team’s NBA basketball game against the Portland Trail Blazers in Portland, Ore., Wednesday, Feb. 13, 2019. The Blazers won 129-107. (AP Photo/Steve Dykes)Golden State Warriors coach Steve Kerr was fined $25,000 by the NBA on Thursday following his rant at officials during his team’s defeat to the Portland Trail Blazers.Kerr needed to be escorted from the court at Portland’s Moda Center on Wednesday after angrily objecting to a flagrant foul called against Draymond Green.ADVERTISEMENT Nadine Lustre’s phone stolen in Brazil The Warriors coach was assessed two technical fouls and ejected after slamming his clipboard to the ground and unleashing a verbal volley against official Kenny Mauer.Kerr’s fine was confirmed by NBA vice president of basketball operations Kiki VanDeWeghe.FEATURED STORIESSPORTSGolden State Warriors sign Lee to multiyear contract, bring back ChrissSPORTSCoronation night?SPORTSThirdy Ravena gets offers from Asia, Australian ball clubsKerr later spoke to reporters about his angry reaction, explaining he was baffled by the decision to call a foul on Green for what looked like an innocuous challenge.“I was just shocked that it was called a flagrant foul,” Kerr said. Ginebra beats Meralco again to capture PBA Governors’ Cup title “That was head-scratching that could be called a flagrant foul. I mean, the guy’s going to go up for a dunk, you got to make sure he doesn’t dunk it. So I told Kenny I beg to differ.”Green was equally bemused, suggesting he was being penalized over-harshly because of his checkered disciplinary record.“I got a lot of ball,” Green said of the foul. “I don’t know. It’s the Draymond rule.”Green however saluted Kerr’s response to the incident.“I loved that too,” Green said. “That was amazing. It’s great.”ADVERTISEMENT Gretchen Barretto’s daughter Dominique graduates magna cum laude from California college View comments Don’t miss out on the latest news and information.
During the Order of Restricted Access, a person must not enter or remain in the restricted area unless the person:a) first receives written authorization from a Wildfire Management Branch officialb) enters the area only in the course of travelling to and from his or her residence- Advertisement -This Restriction applies from 75 kilometre on the Tommy Lakes Road north to the end of the constructed road. A map of the affected area is available online at: http://goo.gl/p8mf4EThe Tommy Lakes fire is currently 4,400 hectares in size. The fire is a modified response fire; it is being actively monitored but not actively suppressed. For more information on this fire and others in the region, click here. An Evacuation Alert is also in place for this fire. More information can be found at: www.prrd.bc.ca