College of ACES
College News

Late winter nitrogen fertilizer application

Published February 28, 2017
corn

URBANA, Ill. – The unseasonably warm and dry weather this February has prompted some corn growers to begin applying ammonia, according to University of Illinois crop sciences professor Emerson Nafziger.

“While we don’t often have the option to apply this early due to frozen or wet soils, late February and early March is an acceptable time to apply ammonia, as long as we do it carefully,” Nafziger says. “Compared to fall application, late winter application introduces nitrogen a little closer to the time the crop will need it, so it’s slightly safer. Still, a warm, wet spring will mean a lot of nitrate present when plant uptake kicks in. So using a nitrification inhibitor with ammonia applied now makes sense.”

After application, ammonia converts to ammonium, which attaches to negative charges on soil and organic matter, and does not move in the soil. When soils warm up, bacteria begin to convert ammonium to nitrate, which can hitch a ride with water moving through the soil. In this way, nitrate can end up in tile lines and out of the field. This is why it is important to keep nitrogen in its ammonium form as long as possible.

Nafziger says that soil samples taken after ammonia application last fall are showing that soil nitrogen levels held up well through late January. With little rainfall in February, he expects that is still the case.

“Late January samples showed that a little more than half of the nitrogen we recovered following fall application was in the nitrate form, and that this percentage was a little lower where we used an inhibitor. There is less nitrate now than we found a year ago following warm, wet weather at the end of 2015. Nitrogen should stay in the soil as long as the soils stay cool and the weather does not turn unusually wet.

“Some producers prefer to wait to apply ammonia until closer to the time the crop will need it. Having dry soils now increases the chances of having soils dry enough to allow application later,” Nafziger says. “Fertilizer materials that contain nitrate, like UAN solution or urea, should not be applied this early; their application should be close to or after planting. Applying nitrogen close to the time the crop needs it is one of the best ways to limit the potential for loss of nitrogen.”

For more information on this topic, visit Nafziger’s Bulletin post.

Study shows Americanization may be fueling unhealthy eating in Jamaica

Published February 27, 2017

URBANA, Ill. – Previous research has shown that viewing high amounts of media can negatively impact dietary habits, and these unhealthy habits are a driving force behind obesity and its associated health complications. Even though previous research has linked increased TV consumption with unhealthy eating habits, not much research has focused on the impact that media consumption may have on individuals from different cultures.

A study published recently in Child Development by University of Illinois researcher Gail Ferguson, an assistant professor in human development and family studies, explores whether globalization and the spread of U.S. media could be influencing behaviors and eating habits in developing regions.

Part of Ferguson’s work revolves around the concept of remote acculturation, or the way in which youth and families from around the world are internalizing American culture and how this affects their identities and behaviors. Ferguson points out, “If you start to think and act like people in another country, then maybe you’ll start to take on their health behaviors as well.”

Ferguson has since launched remote acculturation research in the Caribbean island of Jamaica, and over the past several years, has found that two out of three adolescents in urban areas of Jamaica identify only with traditional Jamaican culture. However, one in three adolescents identify with both Jamaican and American cultures—essentially “Americanized Jamaicans” as Ferguson calls them, or “Jahmerican” as some youngsters in one of her studies suggested.

With this in mind, Ferguson’s research team set out to determine the extent to which youth and families from developing regions are incorporating American culture into how they think, feel, and behave, and how this may be associated with their health. “We really wanted to know what this looks like for an individual,” says Ferguson. “Would feeling somewhat American be linked to watching more American cable TV, and would this bring along unhealthier eating habits?”

To explore this idea, Ferguson’s team focused on 330 randomly selected adolescents in Jamaica, ranging in age from 11 to 18, and their mothers. The participating families completed questionnaires to gain a sense of how much they identified with and enjoyed Jamaican culture, American culture, or a combination of the two; how much U.S. cable TV they watched every day; and what their eating habits were.

What they found is that adopting a part-American identity was linked to watching more hours of U.S.-produced TV per day, which was then linked to eating more unhealthy foods. Ferguson and her team found that it was more likely that feeling American predicted watching American cable, rather than the other way around. For example, adolescents and mothers in Jamaica who felt more American tended to consume more processed foods, prepackaged meals, sodas, and American-style fast food (some of which are viewed as a status symbol), and the link between their American identification and their unhealthy eating was partially explained by their U.S. cable-viewing habits. Additionally, there was a stronger mother-daughter connection because mothers’ U.S. cable viewing was associated with their daughters’ unhealthy eating but not their sons’.

These results have health implications not just for Jamaica, but also for any developing region where youth and families are heavily exposed to American media and are rapidly becoming remotely acculturated. Ferguson points out that any developing regions could experience the effects of this type of acculturation because both American media and food are easily exportable.

But, she stresses, people shouldn’t seek to avoid other cultures, nor can they. “Globalization is like a current,” Ferguson points out. “You can’t stop it; there is no way to pull anyone out of it, but instead we want to teach people to swim, to hold their own, so that they are not swept away without realizing what is happening.”

Ferguson is taking these research findings and using them to help inform the development and evaluation of the JUS Media? Programme, a food-focused media literacy intervention for families in Jamaica targeting food advertising on U.S. cable that is jointly funded by the Christopher Family Foundation Food and Family Program and the National Institutes of Health. Through this project, Ferguson and other researchers are seeking to implement an effective global family health intervention program in developing regions, starting with Jamaica as a case study. By acknowledging remote acculturation and addressing U.S. media influences in their nutrition intervention, the project has the potential to make a substantial contribution to improving diet and decreasing risk for chronic disease in developing regions.

“Feel American, Watch American, Eat American? Remote Acculturation, TV, and Nutrition among Adolescent-Mother Dyads in Jamaica” is published in Child Development. Additional co-authors of the paper were Henna Muzaffar, visiting research coordinator in food science and human nutritionMaria I. Iturbide, assistant professor in psychology at Humboldt State UniversityHui Chu, assistant professor in psychology at Purdue University, Northwest; and Julie M. Meeks, deputy principal of the University of the West Indies Open Campus.

News Source:

Gail Ferguson, 217-300-0365

News Writer:

Tyler Wolpert

Hog prices outperform expectations

Published February 27, 2017

URBANA, Ill. – The pork industry outlook has experienced a major shift to the upside. Pork producers are pleased to see 2017 hog prices higher than expected. The low point for the industry was in late November when hog prices dropped to near $32 per hundredweight on a live weight basis. According to Purdue University Extension economist Chris Hurt, recent live prices have reached the mid-$50s and have pulled the industry out of deep losses into profitability.

“The leading reason for the more favorable outlook is lower retail pork prices,” Hurt says. “Some have mentioned how strong pork consumption has been this year. One reason for that strength is lower retail pork prices. The ‘law of demand’ says that people will buy more when prices are lower, and retail pork prices have moved lower.”

Retail pork prices peaked in 2014 because of reduced supplies due to the porcine epidemic diarrhea virus and have generally been falling since 2015. In the final quarter of 2016, retail pork prices dropped 26 cents per pound from the same period one year earlier. The downward movement continued in January of this year with retail pork prices down 22 cents per pound from one year earlier.

“Another issue contributing to the extremely low prices for pork producers last fall was the small portion of the retail dollar getting back to producers,” Hurt says. “Another way of saying this is that the margins for the processors and retailers remained substantially higher than normal. As a result, the portion of the retail pork dollar that got back to the producer dropped to 17.5 percent. This was lower than the previous record low of 18.4 percent in the financially tragic final quarter of 1998.”

Data this year are only available for January, but in that month the producer share increased to 22 percent. In cents per pound, the hog producer received 15 cents more per retail pound. That amounts to about $9 per hundredweight higher prices on a live hog. Lower retail prices are moving more pork and the pork producer is getting a higher percentage and a higher total value from the pork being sold.

According to Hurt, for the rest of 2017, there is room for even lower retail prices and a higher percentage of that retail price getting back to the hog producer.

“Probably the biggest opportunity for hog producers is the advent of new processing capacity coming on line in the last half of 2017,” Hurt says. “The added competition for hogs will likely reduce the farm-to-wholesale margins with much of that reduction bid into higher hog prices. In 2016, for example, USDA reported the farm-to-wholesale margin as 70 cents per retail pound compared to 58 cents in 2015. Export demand remains a positive for the 2017 hog price outlook as well. USDA expects a 4 percent increase in exports with little change in imports.

“Pork supplies are not the reason for higher hog prices in 2017,” Hurt continues. “So far this year, pork production has been about 3 percent higher than for the same period last year.”

Live hog prices are now expected to average near $51 for 2017, up from $46 in 2016. Live prices are expected to average in the very high-$40s in the first quarter, then move to the low-to-mid-$50s in the second and third quarters, and then finish the final quarter in the mid-$40s.

Total costs of production for 2017 are expected to be near $50 per live hundredweight, similar to the annual forecast price of hogs. If so, Hurt says this means pork producers will recover full costs of production in 2017. Losses in the first and fourth quarters would be offset by profits in the second and third quarter.

“There has been an overall improvement in prospects for animal and animal product prices since last fall,” Hurt says. “That’s true for beef, pork, and milk markets. The source of that improvement may well be related to the general improvement in the anticipated economic growth rates for the United States. Think of the stock market increases since the election. These increases are largely based on anticipated policy that will stimulate the economy, including tax cuts, infrastructure spending, and reduced regulations.”

Hurt says markets for animal products remain vulnerable to at least three outcomes that could differ from current optimism: 1) The anticipated economic stimulus is not implemented, 2) The strength of the U.S. dollar slows agricultural export sales from anticipated levels, and 3) The United States moves in a direction of more protectionism that increases trade barriers and reduces our agricultural export sales potential.

“Each industry is trying to figure out what the new administration means for them,” Hurt says. “Agriculture incomes are importantly influenced by the domestic economy, by the global economy, by exchange rates, and by trade. Agriculture, like other industries, must take a ‘wait- and-see’ attitude.”

 

Andres Ham studies impacts of minimum wage in Honduras

Published February 27, 2017

As part of the ACES International Graduate Grants research program, Andrés Ham, a PhD student in Agricultural and Consumer Economics advised by Dr. Kathy Baylis, traveled to Honduras to study the consequences of minimum wage policy in a developing country.

“Minimum wages in developing countries tend to be sizable, are less likely to be rigorously enforced, and labor markets are often segmented into formal and informal sectors with minimum wage policy only covering formal workers. Given that most developing countries implement minimum wage policies, understanding their consequences on labor markets is critical for economic growth, developing effective labor policy, and poverty alleviation,” says Ham.

While in Honduras, Ham consulted with the National Statistics Institute, the Director of Wages in the Ministry of Labor, as well as sources outside the government including employers’ and workers’ organizations, and various other stakeholders.

“Together these viewpoints provided a comprehensive understanding of minimum wages in Honduras from the perspective of government, employers, and workers. This insight allowed me to qualify my results and better explain my findings,” says Ham.

Considering formal and informal sector jobs, Ham’s findings suggest that the costs of increasing minimum wages outweigh the benefits in this developing country. “The policy implication is that setting high minimum wages has detrimental effects on labor markets, well-being, and compliance,” says Ham.

His research was featured in the World Bank’s Development Impact blog (link here: http://blogs.worldbank.org/impactevaluations/should-developing-countries-increase-their-minimum-wages-guest-post-andr-s-ham, was shared on social media by the World Economic Forum, and was reported by a local newspaper in Honduras.

The impact of Ham’s work continues:  

“The exposure received by the study prompted the government, employers, and unions to verbally commit towards increased cooperation to help solve some problems with minimum wage policy in Honduras. Currently, I am assisting the Ministry of Labor to help design a formula to measure changes in worker productivity, a key input to decide minimum wage changes. This addresses one of several jointly identified priorities: a systematic way to decide annual increases in minimum wages, improving enforcement, and creating safeguards to mitigate the negative effects from minimum wage hikes,” says Ham.

Ham is one of twelve ACES graduate students who received funding as part of the third round of the Graduate Student International Research Grants Program.

The Office of International Programs is currently accepting proposals for the 2017 program; proposals are due March 6. Click here for more information.

New gene for atrazine resistance identified in waterhemp

Published February 23, 2017
waterhemp
  • Waterhemp, a common agricultural weed, has become increasingly resistant to atrazine and other herbicides.
  • Waterhemp uses a class of enzymes known as GSTs to detoxify herbicides, but the exact GST responsible for atrazine resistance was not known until recently.
  • University of Illinois researchers used molecular methods to identify a gene for GST-based atrazine resistance.
  • Knowledge of the gene will allow for easier diagnosis and could lead to the development of more targeted control options.

URBANA, Ill. – Waterhemp has been locked in an arms race with farmers for decades. Nearly every time farmers attack the weed with a new herbicide, waterhemp becomes resistant to it, reducing or eliminating the efficacy of the chemical. Some waterhemp populations have evolved resistance to multiple herbicides, making them incredibly difficult to kill.

Adding to the challenge is the fact that waterhemp can evolve resistance in at least two ways. In target-site resistance, a gene mutation changes the protein that the herbicide is designed to attack. With an ill-fitting protein binding site, the herbicide becomes ineffective. The plus side of target-site resistance is that it is relatively easy to identify using standard lab procedures.

Metabolic resistance is a different beast. Plants use any one of hundreds of possible enzymes to detoxify the chemical, rendering it useless. Although University of Illinois weed scientists Dean Riechers, Rong Ma, and Josh Skelton recently developed a quick and easy test for metabolic resistance, they still had no way of knowing which enzyme was responsible. 

Until now.

“We think we found the needle in the haystack,” Riechers says.

Riechers and his colleagues focused on metabolic resistance to atrazine, a chemical that has been used for decades and is still sprayed on approximately 80 percent of the corn acreage in the United States, despite increasing resistance and concerns about environmental impacts.

From previous research at U of I, the team knew that resistant waterhemp metabolizes atrazine with a class of enzymes known as GSTs. “Plants are known to have anywhere from 50-120 GST genes. We wanted to know if resistance was coming from just one of those, and whether we could find it,” Riechers says.

Former graduate student Anton Evans isolated candidate GST proteins from waterhemp and looked at their expression in resistant and sensitive plants. One of the GST proteins was extremely abundant in resistant plants, but almost nonexistent in sensitive plants. Graduate student Sarah O’Brien looked more closely at the gene encoding that GST protein, and, in particular, at its variants or alleles. She noticed that when two dominant alleles for this gene were present, it took more than 14 times the recommended atrazine rate to damage the plants.

“The heterozygous plants – those with just one copy of the dominant allele – had much higher injury. In an experiment with four or five heterozygous plants, two or three would die and the others were stunted and had a lot of dead tissue. But the homozygous resistant plants – those with two copies of the dominant allele – almost looked like they hadn’t been sprayed,” O’Brien says.

“Plants without the dominant allele just got hammered, even at low herbicide application rates,” Riechers adds.

This evidence, along with more detailed molecular data, gives the team confidence that they have discovered something unique. “This may be the only case where we’ve actually found the gene responsible for metabolic resistance in a broadleaf weed, as opposed to target-site resistance,” Riechers explains, “for any herbicide.”

Going forward, the test for this gene will be similar to the test for target-site atrazine resistance. The new information also could be used by industry to develop new chemicals to control waterhemp.

“As long as we know the gene, you could potentially knock it out and make the plant sensitive again. You could design a GST-inhibiting chemical that’s specific to this one GST,” Riechers says.

The article, “Biochemical characterization of metabolism-based atrazine resistance in Amaranthus tuberculatus and identification of an expressed GST associated with resistance,” is published in Plant Biotechnology Journal. Anton Evans Jr., Sarah O’Brien, Rong Ma, Aaron Hager, Chance Riggins, Kris Lambert, and Dean Riechers contributed to the paper. Syngenta U.K. supported the project.

STRONG Kids program receives additional support from the National Dairy Council

Published February 23, 2017

URBANA, Ill. – Exploring how multiple factors contribute to the development of childhood obesity, the Family Resiliency Center’s STRONG Kids Program recently received an additional $548,275 of funding from the National Dairy Council (NDC) to extend its current research project, STRONG Kids 2, through 2019.

STRONG Kids 2 is one of the first comprehensive research projects to explore how individual biology and dietary habits, including milk and dairy consumption, interact with the family environment to provide unique insights into the underlying causes behind childhood obesity. Originally, project participants were to be observed from birth to three years of age. The increased support from the NDC allows researchers to follow participants until they reach five years of age—a critical point for children as they become more vocal about their food preferences and spend more time in out-of-home care.

The increased observational time will be critical in providing a clearer picture of early childhood health. “We are already seeing important shifts in growth during the first year of life in this group of infants,” says the program’s co-director Barbara H. Fiese. “Being able to track these patterns into the preschool years will allow us to identify potential points of intervention to protect children against unhealthy weight in the early years. We are tracking the importance of breastfeeding, timing of introduction of solids, presence of dairy, and good sleep habits as predictors of healthy outcomes for these children. Being able to do so for five years is quite remarkable.” 

The additional support has also allowed researchers to expand recruitment to ensure enough families are retained over the length of the study. The expansion of the participant pool and the length of time they are involved in the project is significant according to co-director Sharon Donovan. “Being able to expand the cohort and the length of the time that we are obtaining data are both important because they will ensure that we have sufficient statistical power to examine health and dietary changes over time a time,” Donovan says, “and we will be able to follow the children as they are transitioning from preschool or home to school.” 

Project staff has worked hard over the past three years to recruit a cohort of expectant mothers throughout central Illinois to participate in the project. At present, the project has passed its recruitment goal of 450 participating families.

Over the course of the study, biological samples and measurements are collected from this cohort at intervals, and mothers are surveyed about weaning, dietary habits, and household routines, as well as children’s emotions, feeding styles, and milk and dairy consumption. The new funding allows researchers to enhance these measurements through added questionnaires and home observations to ensure they have a clearer picture of dietary intake. Says Donovan, “We’re able to add more home observations and 24-hour dietary recall measures, which will complement and extend upon the current measures of dietary intake in the cohort.” 

Ultimately, the findings from STRONG Kids 2 will serve as the foundation for obesity prevention and intervention programs throughout the country.

Pages