URBANA, Ill. – A Boeing 747 burns one gallon of jet fuel each second. A recent analysis from researchers at the University of Illinois estimate that this aircraft could fly for 10 hours on bio-jet fuel produced on 54 acres of specially engineered sugarcane.
Plants Engineered to Replace Oil in Sugarcane and Sweet Sorghum (PETROSS), funded by the Advanced Research Projects Agency - Energy (ARPA-E), has developed sugarcane that produces oil, called lipidcane, that can be converted into biodiesel or jet fuel in place of sugar that is currently used for ethanol production. With 20 percent oil - the theoretical limit - all the sugar in the plant would be replaced by oil.
"Oil-to-Jet is one of the direct and efficient routes to convert bio-based feedstocks to jet fuel," said Vijay Singh, Director of the Integrated Bioprocessing Research Laboratory and Professor in the Department of Agricultural and Biological Engineering at U of I. "Reducing the feedstock cost is critical to improving process economics of producing bio-jet fuel. Lipidcane allows us to reduce feedstock cost."
This research analyzed the economic viability of crops with different levels of oil. Lipidcane with 5 percent oil produces four times more jet fuel (1,577 liters, or 416 gallons) per hectare than soybeans. Sugarcane with 20 percent oil produces more than 15 times more jet fuel (6,307 liters, or 1,666 gallons) per hectare than soybeans.
"PETROSS sugarcane is also being engineered to be more cold tolerant, potentially enabling it to be grown on an estimated 23 million acres of marginal land in the Southeastern U.S.," said PETROSS Director Stephen Long, Gutgsell Endowed Professor of Plant Biology and Crop Sciences at the Carl R. Woese Institute for Genomic Biology at U of I. "If all of this acreage was used to produce renewable jet fuel from lipid-cane, it could replace about 65 percent of national jet fuel consumption."
"We estimate that this biofuel would cost the airline industry $5.31 per gallon, which is less than most of the reported prices of renewable jet fuel produced from other oil crops or algae," said Deepak Kumar, postdoctoral researcher in the Department of Agricultural and Biological Engineering at U of I and lead analyst on the study.
This crop also produces profitable co-products: A hydrocarbon fuel is produced along with bio-jet fuel or biodiesel that can be used to produce various bioproducts. The remaining sugar (for plants with less than 20 percent oil) could be sold or used to produce ethanol. In addition, biorefineries could use lipidcane bagasse to produce steam and electricity to become self-sustainable for their energy needs and provide surplus electricity, providing environmental benefits by displacing electricity produced with fossil fuels.
The paper "Biorefinery for combined production of jet fuel and ethanol from lipid-producing sugarcane: a techno-economic evaluation" is published by Global Change Biology Bioenergy (10.1111/gcbb.12478).
PETROSS (Plants Engineered to Replace Oil in Sugarcane and Sorghum) is a research project transforming sugarcane and sweet sorghum to naturally produce large amounts of oil, a sustainable source of biofuel. PETROSS is supported by the Advanced Research Projects Agency-Energy (ARPA-E), which funds initial research for high-impact energy technologies to show proof of concept before private-sector investment.
Soybean consumption finishes strong in 2016-17
URBANA, Ill. – The 2016-17 marketing year for soybeans closed with strong consumption in soybean crush and export numbers. According to University of Illinois agricultural economist Todd Hubbs, USDA’s current estimate of 370 million bushels for the 2016-17 marketing-year soybean ending stocks may be lowered due to the stronger-than-expected finish in consumption. “Despite the recent strength in soybean consumption, the current focus is squarely on the level of production for the 2017 soybean crop and, in particular, national yield potential,” Hubbs says.
The USDA's Oilseed Crushings, Production, Consumption and Stocks report released on Sept. 1 estimated domestic crush for July at 156 million bushels. At 1 percent higher than July 2016, the report confirmed a strengthening trend in soybean crush levels that began in June after four consecutive months of lower crush numbers from last year. Through July, total yearly soybean crush came in at 1,753 million bushels. For crush to meet the USDA estimate for the 2016-17 marketing year, August crush is required to be 137 million bushels. August 2016 crush came in at 140.6 million bushels.
“If crush levels continue to see recovery from early year weakness at the pace witnessed in June and July, soybean crush for the fourth quarter is estimated to total 451.6 million bushels,” Hubbs says. “The potential to exceed the current USDA estimate of 1,890 million bushels by five million bushels is a distinct possibility.”
USDA projections for 2016-17 marketing-year soybean exports total 2,150 million bushels as of the August 10 World Agricultural Supply and Demand Estimates report. Census Bureau export estimates through July place soybean exports at 2,061 million bushels. Census Bureau export totals came in 47 million bushels larger than cumulative marketing-year export inspections over the same period. As of August 31, cumulative export inspections for the current marketing year totaled 2,123 million bushels.
“If the same difference in export pace through July is maintained, soybean exports totaled 2,170 million bushels for the 2016-17 marketing year, 20 million bushels larger than the current USDA estimate,” Hubbs says. “Fourth quarter soybean exports would total 258.5 million bushels.
“Seed and residual use through the third quarter of the marketing year is estimated at 203.1 million bushels,” Hubbs adds. “If the USDA’s feed and residual use estimate of 128 million bushels is correct, fourth quarter disappearance for seed and residual use would total -75.1 million bushels.”
Soybean stocks on June 1 were estimated at 963.4 million bushels. By including an estimate of soybean imports during the fourth quarter, an estimate of total supply available during the quarter can be calculated. Census Bureau estimates of soybean imports in June and July totaled 2.8 million bushels. Imports for the quarter could come in at around 4.8 million bushels, resulting in a total supply of 968.2 million bushels.
Total consumption of soybeans during the fourth quarter is calculated to be 635 million bushels.
“Given a supply during the quarter of 968.2 million bushels, Sept. 1 stocks are calculated at 333.2 million bushels,” Hubbs says. “Although uncertainty exists for the magnitude of seed and residual use, the final ending-stocks estimate is expected to be within a relatively narrow range.
Strong finishing numbers for the 2016-17 marketing year are currently being eclipsed by the USDA forecasts for soybean crop production. The August Crop Production report forecast 2017 soybean production at 4,381 million bushels. In particular, the soybean yield forecast of 49.4 bushels per acre is the subject of extensive speculation due to higher-than-expected yield forecasts in major producing states. The question is whether the soybean acreage or yield will change enough to result in lower soybean production.”
According to Hubbs, historical data suggests the soybean yield forecast will change in future Crop Production reports. Using data from 1990-2016, the change in the soybean yield forecast from August to September declined in 12 of those years. The decline exceeded 1 bushel in four of those years and exceeded 2 bushels in 2003. During the last five years, USDA August and September forecasts of soybean yield have been below the final yield estimate. Recent cool temperatures and relatively dry conditions in many areas could be detrimental to soybean development.
“Despite the potential weather impacts, many market analysts have raised previous soybean yield projections with a general expectation of the September forecast coming in at or slightly lower than the August forecast,” Hubbs says.
Current developments in soybean acreage can be inferred from data reported to the Farm Service Agency by producers enrolled in federal farm programs. FSA released the first report for 2017 on August 10. Producers reported 88.2 million acres of planted soybeans, which is lower than the 89.5 million acres amount currently used by the National Agricultural Statistics Service.
“The FSA figures should grow as reporting is completed,” Hubbs says. “The FSA report indicated that 436,610 acres of prevent planting in soybeans had been certified thus far in 2017. Last August, prevent-plant soybean acreage was reported at 237,057 million acres and the final 2016 report totaled 236,609 acres. Although higher than last year, the current prevent-planting acreage provides no indication of a significant change in soybean planted or harvested acreage in 2017.
“The release of the USDA reports on Sept.12 could induce significant volatility in soybean prices,” Hubbs says. “A major adjustment of soybean yields in either direction will have an outsized impact of price movements over the short run. Over a longer horizon, the current strength in soybean consumption provides a positive signal for soybean prices.”
Weed seed destructor demonstration planned at Illinois
URBANA, Ill. – Farmers battling herbicide resistant weeds could add a new weapon to their arsenal, but it’s not a chemical. The Harrington Seed Destructor destroys this year’s weed seeds during harvest, preventing establishment in the spring. Farmers can see it in action Oct. 12 at the University of Illinois.
“I’ll admit I was a bit skeptical about whether the HSD would work on waterhemp, but using it during last year’s harvest reduced waterhemp populations in this year’s crops,” says Adam Davis, ecologist in the Department of Crop Sciences and with the USDA Agricultural Research Service.
The field tour will begin at 1 p.m. at the Crop Sciences South First Street Facility at 4202 South 1st Street in Savoy. The tour will also include visits to two nearby field sites.
Attendees are not required to register, and all are welcome. For more information on the Harrington Seed Destructor, visit http://go.illinois.edu/hsd, or contact Taylor Stewart at 217-300-6299 or firstname.lastname@example.org.
A decade later, older Americans are still going hungry
URBANA, Ill. – Hunger does not respect age. A recent report comparing data from 2007 to 2015 finds 5.4 million people age 60 or older in the U.S., or 8.1 percent, are food insecure. Although this percentage went down from 2014 to 2015, it’s still unacceptable, according to a University of Illinois economist.
“After six consecutive years of increased hunger in seniors since the Great Recession began, the slight drop in 2014 is good news, but not good enough,” says Craig Gundersen, who coauthored the report. “And it’s important to remember that the decrease is in hunger on the national scale. Some individual states saw an increase.”
The report identifies the top 10 states in terms of senior food insecurity rates. “Seven of those 10 states are in the South, plus New Mexico, New York, and Indiana,” Gundersen says. The report states that when seniors who experience marginal food security are included, the rates vary from 6.1 percent in North Dakota to 24.3 percent in Mississippi.
Gundersen says seniors who reported a disability were disproportionately affected, with 25 percent reporting food insecurity and an additional 13 percent reporting marginal food security.
“Food insecurity is known to adversely affect a person’s health, and the implications can be particularly problematic for seniors,” Gundersen says. “Compared to food-secure seniors, food-insecure seniors consume fewer calories, vitamins, and other key nutrients. They are also more likely to experience negative health conditions, including depression, asthma, and chest pain.”
Gundersen says the Supplemental Nutrition Assistance Program (SNAP, formerly known as the Food Stamp Program) has been demonstrated to reduce food insecurity. He recommends that policymakers and program administrators pursue efforts to increase participation in SNAP, with a particular emphasis on older adults.
The report, “The State of Senior Hunger in America in 2015,” was produced by Feeding America in partnership with The National Foundation to End Senior Hunger. It was coauthored by James Ziliak from the University of Kentucky Center for Poverty Research and Craig Gundersen from the University of Illinois.
Gundersen is the Soybean Industry Endowed Professor in Agricultural Strategy and professor in the College of Agricultural, Consumer and Environmental Sciences Department of Agricultural and Consumer Economics at the University of Illinois and a member of the Division of Nutritional Sciences at U of I.
Herbicide rotation ineffective against resistance in waterhemp
URBANA, Ill. – Farmers have been battling herbicide-resistant weeds for generations. A common practice for most of that time has been to rotate between different herbicides every season. But despite farmers’ best efforts, herbicide resistance has grown through the years, with some weed populations showing resistance to not one but four or five different herbicides. A new study from the University of Illinois explains why herbicide rotation doesn’t work.
“If you were to ask farmers what is the one thing you can do to delay resistance evolution, they’ll say rotate herbicides. This study shows that’s not true,” says Pat Tranel, Ainsworth Professor in the Department of Crop Sciences at U of I.
Herbicide resistance results from random genetic mutations that keep weeds from being harmed by a particular herbicide. When farmers continually spray the same herbicide year after year, those with the mutation, referred to as a resistance allele, survive and reproduce. Over time, the proportion of plants with the resistance allele grows.
Conventional thinking says that any defense trait—in this case, herbicide resistance—should come at a cost to the plant. It might be well protected against the herbicide, but it might not grow as tall, or flower as early. When the trait reduces a plant’s reproductive output, that’s known as a fitness cost.
A fitness cost to herbicide resistance should be apparent in years when alternative herbicides are used. “If plants have glyphosate resistance, but they’re sprayed with 2,4-D, for example, the majority of those plants will die because they’re not resistant to 2,4-D. But no herbicide kills 100 percent of the weeds, resistant or not,” Tranel says. “You have to think about the small percentage that live.
“If there’s a high fitness cost to the glyphosate resistance allele, most of the surviving plants will be small or will flower late and they won’t produce many seeds. But if the fitness cost is low, those plants will produce just as many seeds as plants that don’t have the allele. Herbicide rotation relies on the assumption that the fitness cost is high.”
To test that assumption, Tranel and his research team designed a simple, if time-consuming, experiment. They took female waterhemp plants with no resistance alleles and allowed them to be pollinated by males with resistances to five different herbicides. Because female waterhemp plants can produce as many as a million seeds, it was easy to get the 45,000 they needed to start the experimental population.
They scattered seeds on the soil floor of a greenhouse and just let them grow. When females started producing seeds, they were collected to start the next generation. Between generations, the researchers removed all the plants and made sure no seeds remained in the soil. The cycle was repeated for six generations over three years.
How could the study test the efficacy of herbicide rotation if no herbicides were sprayed? It comes back to fitness cost. Remember, the assumption is that without the herbicide, the resistance allele offers the plant no benefit, and could carry a cost. The researchers were allowing those fitness costs a chance to play out during the study.
“If the resistance alleles had a high fitness cost, we should have seen them decrease in frequency or disappear over the six generations,” Tranel says. Instead, the alleles for almost all five resistance types were essentially unchanged.
The allele that confers resistance to ALS-inhibiting herbicides was statistically lower after six generations, but the decrease was tiny in terms of real numbers. “The frequency decreased by less than 10 percent a year,” Tranel says. “At the rate it was decreasing, even if a farmer used an alternative herbicide for 9 years, the frequency of resistance to ALS inhibitors would only be cut in half.”
Waterhemp has two known strategies to ward off glyphosate-based herbicides, such as Roundup, and the researchers tested the frequency of both.
“Plants with one type of glyphosate-resistance mechanism make multiple copies of the target site for glyphosate, a gene called EPSPS. And that’s what we found went away; the proportion of plants with multiple copies of EPSPS decreased about 15 percent with each generation,” Tranel says. “But I want to emphasize something: even though it decreased quite a bit, it didn’t disappear by any stretch. If you applied glyphosate, that resistance mechanism would come back even if you waited six years between applications.”
The other glyphosate-resistance mechanism involves the same gene. This time, it’s a specific mutation in the EPSPS gene that guards the plant against the effects of glyphosate. The researchers found that the mutation in EPSPS actually increased about 10 percent in each generation. Tranel thinks it may have been easier for one mechanism to replace the other because they both involve the same gene.
“This study tells us that fitness cost isn’t going to help you much in terms of herbicide resistance, so even long rotations aren’t going to work,” Tranel says. “I tell farmers, ‘Once you have resistance, you’re stuck with it.’ It gives us that much more incentive to do the right things to avoid resistance in the first place. That means using multiple herbicides, using a PRE and coming back with a POST. If you have escapes, getting out of your tractor and getting rid of them before they set seed. Because if they set resistant seed, this study tells you that you will have that resistance trait for life.”
The article, “Limited fitness costs of herbicide-resistance traits in Amaranthus tuberculatus facilitate resistance evolution,” is published in Pest Management Science. Tranel’s co-authors include Chenxi Wu and Adam Davis, from U of I. The study was supported by a grant from USDA NIFA [grant no. 2012-67013-19343].
Relationship science: How can couples keep moving forward
URBANA, Ill. – For some couples in romantic relationships, just staying together is good enough. But others want to see their relationship move forward—to get better and better—and are willing to put in the effort to get there.
Family studies researchers at the University of Illinois who study the science behind maintaining romantic relationships focus their work on the central organizing unit—the relationship—rather than on the individual. Through their work, they hope to find out what works and, maybe, what doesn’t in keeping a relationship moving forward.
“We know relationships are key,” says Brian Ogolsky, associate professor in the Department of Human Development and Family Studies at U of I. “We spend all of our time in these relationships. Whether we are at home, with our siblings, our parents, or our colleagues, these are all extremely important. And consequently we spend very little time alone with our thoughts. So it’s critical that we carefully and methodically understand what’s going on in relationships and what is unique that two individuals bring that you can’t get from studying person ‘x’ and person ‘y’ separately.”
In a recent study published in the Journal of Family Theory and Review, Ogolsky and his research team discuss romantic relationship maintenance and the two primary motives behind a couple’s attempts at staying together: threat mitigation and relationship enhancement.
Ogolsky calls these “macro-motives,” or the main reasons people maintain their relationships. In their study, the researchers provide a visual framework of how relationships may be maintained by staving off threats or moved forward by relationship enhancement strategies, which involve putting effort into the relationship for the pleasure of it. For the most part, relationships include a combination of both.
“Threats to the relationship come from all kinds of different places,” he explains. “Generally, there are many threats early in relationships that can cause problems, but that is not to say that these disappear later. We know couples cheat in the long-term, people end up in new work places and in new situations where possible alternative partners show up, conflicts arise, or a lack of willingness to sacrifice time for your partner emerges.”
Some threat mitigation tactics can actually become enhancement strategies over time, Ogolsky says, but adds that the reverse is not usually true. “We get to a place where we are pouring energy into the relationship simply because we want to keep the relationship moving forward rather than just mitigating threats.”
In their integrative model of relationship maintenance, the researchers also illustrate individual versus interactive components of maintenance. “This question of ‘is this an individual thing or is this a couple-level thing’ often goes unanswered. But as we were doing this review, we started noticing that there are ways to maintain the relationship that we can characterize as ‘more or less in our own heads.’ We are doing something to convince ourselves that this is a good relationship and therefore it’s good for our relationship,” Ogolsky explains. “Things like positive illusions, the idea that we can believe our relationship is better than it is or that our partner is better than he or she is. We can do that without our partner.”
Mitigating conflict, however, is something that partners must do together. “Good conflict management or forgiving our partner for doing something wrong is an interactive process. When a threat comes in, we can do one of two things: we can ditch our partner or forgive them over time.”
The same is true of enhancement strategies: partners can do things individually or interactively. “Individually, even the act of thinking about our relationship can be enhancing. Whereas engaging in leisure activities together, talking about the state of our relationship, these are all interactive,” Ogolsky says.
But why study relationship maintenance as a science?
While Ogolsky rarely offers direct interventions to couples, he explains that he tends to study the positive side of relationships because of what can be learned from people who are going through what, he says, is inherently a very turbulent thing.
“Relationships have ups and downs. I never go into my work saying people should stay together or they should break up. Relationships are individualized, a unique pairing of people that comes with a unique history. What we are talking about here are processes that exist across different kinds of couples, some of which work very well for some people, some of which may not work for some people. I am interested in understanding processes that keep relationships moving.”
For the review, Ogolsky and his team searched for previous research, regardless of discipline, dealing with relationship maintenance. They eventually discussed about 250 studies in the paper (reviewing more than 1,100) that deal with romantic relationships and that met their criteria. Ogolsky hopes the review will bring together relationship scholars from across many disciplines.
The paper, “Relationship Maintenance: A review of research of romantic relationships,” is published in the Journal of family Theory and Review. Co-Authors include Brian G. Ogolsky, J. Kale Monk, TeKisha M. Rice, Jaclyn C. Theisen, and Christopher R. Maniotes, all in the Department of Human Development and Family Studies in the College of Agricultural, Consumer and Environmental Sciences at the U of I.
The work is supported in part by a USDA/NIFA HATCH grant (ILLU-793-326).