URBANA, Ill. – How will the rising temperatures expected to occur with global climate change affect soybean growth in the Midwest? Rather than wait and see, researchers at the University of Illinois will use real crop data and computer modeling to better predict future impacts of higher temperatures on agricultural production and identify promising targets for adaptation.
The project is being funded with a $420,000 USDA National Institute for Food and Agriculture grant. U of I environmental scientist Kaiyu Guan is the project director. Carl Bernacchi and Elizabeth Ainsworth are co-project directors. Both are plant physiologists in the U of I Department of Plant Biology and Department of Crop Sciences.
The project will look at how temperature affects major plant processes such as photosynthesis and respiration.
“Higher temperatures in the future may result in accelerated crop growth rate and shorter growing seasons,” says Guan. “There will likely be direct heat stress effects on the various stages in plant reproduction, including number of flowers and pods produced and aborted and the higher temps may increase the plants’ demand for water. All of these factors will play a role in soybean crop yield.”
Guan says the team will combine the temperature free-air controlled enhancement (T-FACE) experiment and a newly developed crop modeling framework (CLM-APSIM). Infrared heating arrays will be used to heat three soybean varieties, representing the major groups planted across the Midwest for two growing seasons, and multiple physiological and biochemical measurements will be taken simultaneously.
“We will then use the experiment results to improve and calibrate the model at the site level,” Guan says. “Using the calibrated model, we will attribute the historical yield loss due to increase temperature to different physiological mechanisms. Ultimately, we will project crop yield for the whole Corn Belt under the various climate scenarios, and quantify the contribution of each mechanism.”
In addition to being an assistant professor in ecohydrology and geoinformatics in the Department of Natural Resources and Environmental Sciences in the College of Agricultural, Consumer and Environmental Sciences at U of I, Guan has a joint appointment as a Blue Waters professor affiliated with the National Center for Supercomputing Applications (NCSA).
Rice bran in weanling pig diets does not reduce growth performance
- Full fat or defatted rice bran can be included in weanling pig diets at up to 20 percent without negatively affecting growth performance.
- Inclusion of 10 percent full fat or defatted rice bran maximized average daily gain.
- Inclusion of 20 percent full fat rice bran maximized the gain to feed ratio.
URBANA, Ill. – Research at the University of Illinois has demonstrated that adding rice bran to weanling pig diets does not have a detrimental effect on growth performance. Rice bran is a co-product of the rice milling process which is often added to swine diets; it is relatively inexpensive, and it may improve gut health in weanling pigs.
A team led by Hans Stein, professor of animal sciences at the U of I, fed diets containing 10, 20, or 30 percent of either full fat rice bran (FFRB) or defatted rice bran (DFRB) to weanling pigs. The growth performance of these pigs was compared to that of pigs fed a control diet based on corn, soybean meal, and whey powder. All diets were formulated to contain the same amount of digestible indispensable amino acids.
"Full fat and defatted rice bran both contain more dietary fiber than corn," says Stein. "Because high fiber concentrations can reduce digestibility of energy and nutrients, we wanted to investigate whether or not including rice bran in the diets would affect growth performance."
For both FFRB and DFRB, increasing inclusion rates decreased the average daily feed intake, probably due to the increased bulk of the diet. Metabolizable energy intake also decreased with increasing inclusion rate of FFRB or DFRB, but pigs fed diets containing DFRB had greater average daily feed intake than pigs fed diets with FFRB.
"With the decreased feed and energy intake, pigs might be expected to gain less when fed diets containing FFRB or DFRB," Stein says. "But that was not what we observed."
There was no difference in final body weight between pigs fed the control corn-soybean meal diet and pigs fed any of the diets containing FFRB or DFRB.
Average daily gain (ADG) for pigs fed diets containing 10 percent FFRB or DFRB was greater than for pigs fed the control diet. Feeding diets containing 20 percent FFRB or DFRB had no effect on ADG compared with the control diet.
The gain to feed ratio (G:F) was greatest in pigs fed diets containing 20 percent FFRB. Inclusion of up to 30 percent DFRB had no negative effect on G:F compared with pigs fed the control diet.
"These results indicate that rice bran can be fed to weanling pigs at inclusion rates of up to 20 percent without compromising growth performance," says Stein.
Funding for this research was provided by AB Vista (Marlborough, UK). Full fat rice bran was donated by Rice Bran Technologies (Scottsdale, AZ).
The paper, "Effects of full fat or defatted rice bran on growth performance and blood characteristics of weanling pigs," was co-authored by Gloria Casas. It was published in a recent issue of the Journal of Animal Science, and can be found online at https://www.animalsciencepublications.org/publications/jas/articles/94/10/4179.
Corn consumption update
URBANA, Ill. – Since early October, the March 2017 corn futures prices have fluctuated in a price range between $3.40 and $3.70. USDA’s World Agricultural Supply and Demand Estimates report released on Jan. 12 presented a mixed signal on corn consumption forecasts with a reduction of 50 million bushels in feed and residual use and an increase in corn used for ethanol by 25 million bushels for the 2016-17 marketing year. The export forecast remained unchanged. Corn prices reflected this information with a moderate response to the 78-million-bushel reduction in production reflected in the Crop Production report that was released on the same day. According to University of Illinois agricultural economist Todd Hubbs, the current pace of corn consumption indicates corn prices may stay in the price range from $3.40 - $3.70 for the next several weeks.
“Thus far in the marketing year, corn exports exhibited considerable strength,” Hubbs says. “Exports through the first quarter of the marketing year came in at 551 million bushels. Accumulated exports through Jan. 19 are 744.5 million bushels. This is a 68 percent increase over the same period last year.” Outstanding sales for this marketing year through Jan. 19 are 793.4 million bushels. Total commitments currently sit at 69 percent of the USDA projection of 2.225 billion bushels. Export shipments and outstanding sales increased during the last three weeks.
“The developing issues with trade policy create uncertainty over the future trajectory of corn exports,” Hubbs says. “At the current pace, the USDA forecast looks attainable despite significant competition due to emerge from South American corn production.”
Hubbs goes on to say the pace of ethanol production in the 2016-17 marketing year is at record levels. Ethanol production averaged over 1 million barrels per day throughout December and thus far in January. Over the last two weeks, ethanol stocks grew by 1.719 million barrels.
“The growth in ethanol stocks may be giving an indication of a slowdown in ethanol production as the margins for ethanol deteriorate,” Hubbs says. Corn consumption to produce ethanol used 1.3 billion bushels in the first quarter of the marketing year. Based on ethanol production since November, corn consumption for ethanol as of Jan. 20 is approximately 2.1 billion bushels. The current record pace of ethanol production may not last, but the 5.325 billion bushels of corn for ethanol production appears attainable for the marketing year.
The pace of corn consumption for feed likely increased from a year ago, Hubbs says. The increase in feed consumption is more modest than initial USDA forecasts and, thus, the 50-million-bushel reduction on Jan.12. Livestock production increases in many sectors provide support for increased corn feed use during this marketing year. The number of cattle on feed on Jan.1, 2017, was slightly larger than last year at 10.61 million head. Placements into feedlots during December 2016 were 17.6 percent larger than last year at 1.79 million head. The number of milk cows on farms in December was 38,000 head larger than last year. Year over year growth was .2 percent. The USDA’s Quarterly Hogs and Pigs report indicated that the inventory of market hogs on Dec. 1, 2016, was 3.7 percent higher than last year. Market hogs across weight groups less than 180 pounds were all greater than 4 percent larger than the previous year. The number of broiler eggs set continuously exceeds the pace of a year earlier by 1 to 2 percent every week. Broiler type chicks placed each week is also running around 2 percent above last year’s pace.
According to Hubbs, despite strong livestock production, a number of factors could be limiting corn feed use. “The increase in ethanol production created an increase in distillers grains production. When combined with a 4 percent decline in distillers grains exports in the first quarter of the marketing year, the availability of distillers grains is apparent. Distillers grains prices declined in central Illinois to an average price in December of $104.84 per ton. This is down over 30 cents from the 2015-16 marketing-year average price. Sorghum feed and residual use increased by 15 million bushels in the Jan.12 report giving an indication of increased feeding of sorghum in many areas. Higher corn prices and lower production levels also contribute to the potential for corn feed use coming in lower than current USDA projections,” Hubbs says.
Currently, the pace of corn consumption appears to be large enough to maintain old-crop corn prices in the $3.40 to $3.70 price band for the next several weeks, barring some economic or policy disturbance, Hubbs adds. “There are no indications currently for higher price movements. A possibility of weakness in corn consumption related to corn used for ethanol production may be forming as ethanol stocks begin to build. A large upward price movement requires a substantial increase in the pace of shipments to export markets, which possesses significant uncertainty concerning our major trading partners, or the emergence of production issues in South America.”
University of Illinois Plant Clinic publishes 2016 herbicide resistance report
URBANA, Ill. – The University of Illinois Plant Clinic has been diagnosing plant problems since 1976, but the array of services provided has grown and become increasingly sophisticated in recent years. Two years ago, the Plant Clinic began using molecular protocols to test for herbicide resistance to glyphosate and PPO inhibitors in waterhemp. Last year, they expanded the service to Palmer amaranth and recently added a method for distinguishing waterhemp and Palmer using molecular methods. In a U of I Bulletin post, the Plant Clinic published a report of their findings for the 2016 season.
“Almost twice as many whole fields were tested in 2016 compared to 2015: 593 vs. 338,” says U of I Extension assistant dean for agriculture and natural resources and Plant Clinic director Suzanne Bissonnette.
The clinic received samples from 10 states across the Midwest in 2016, with the majority of samples coming from Illinois. In the 378 samples from Illinois, 48 percent were resistant to both glyphosate and PPO inhibitors. Resistance to both herbicides was detected in 82 percent of samples from Missouri, but only 11 samples were tested from that state.
“Fields with plants that are positive for both glyphosate and PPO inhibitor resistance are of particular concern, due to the limited possibilities for control of these weeds,” says plant diagnostic outreach Extension specialist Diane Plewa.
Palmer amaranth in Illinois was not known to be resistant to PPO inhibitors, but that is no longer the case according to the Plant Clinic results. “Several samples from southwestern Illinois were confirmed to be PPO inhibitor-resistant (three from Madison, and one from St. Clair counties) in our testing,” Plewa reports.
The tests detect the most common mechanism of resistance to the two chemicals: target-site mutations. However, waterhemp and Palmer amaranth are known to use metabolic pathways to detoxify herbicides in other classes. Therefore, even though more than half of the fields sampled in Illinois did not show resistance to glyphosate and PPO inhibitors, farmers should not assume these weeds can be killed by alternative herbicides.
Herbicide resistance goes viral
URBANA, Ill. – “Think differently. Behave differently. Diversify however you can. Not every practice fits on every acre.” That was the message from University of Illinois weed scientists Aaron Hager and Patrick Tranel when they discussed overcoming herbicide resistance during a Twitter chat last week.
A21. Think differently. Behave differently. Diversify however you can. Not every practice fits on every acre. #askaces— College of ACES (@ACESIllinois) January 19, 2017
#AskACES Twitter chats have been putting researchers from the College of Agricultural, Consumer and Environmental Sciences in the hot seat for a little more than a year now, challenging them to formulate pithy answers to questions asked live by the public during the hour-long chat.
It was an eye-opening experience for Tranel and Hager. “This morning, I told my son to check out ‘pound-sign AskACES’ during the lunch hour. He said, ‘Dad, that’s a hashtag,’” Tranel said. The concept may have been new to the pair, but they clearly enjoyed the 140-character challenge. Hager jokingly answered many questions with “yup” or “nope,” before being coaxed to provide more detail.
A11. Waterhemp? If yes, zero. #askaces— College of ACES (@ACESIllinois) January 19, 2017
A7b. Genetic diversity + herbicide selection = resistance. #askaces— College of ACES (@ACESIllinois) January 19, 2017
But the pair got a chance to expand on their answers during a podcast recorded immediately following the Twitter chat. Hager and Tranel, who represent U of I Extension and academic research staff, respectively, provided both the scientific context and some practical guidance for the problem of herbicide resistance during the 15-minute interview.
The discussion ranged from economics to the evolution of herbicide resistance to strategies for farmers to combat the problem in the field.
“We really have to rethink the idea of simply controlling weeds and give more consideration to how we better manage these populations,” Hager said. “There’s a lot of things that we can do, but one size fits all across the entire state or Midwest? Certainly not. Using a lot of little hammers in the long run is going to be much more sustainable than any one big hammer.”
That’s 354 characters, in case you’re counting.
Find the podcast and more in the #AskACES series at the ACES website and on Twitter.
Potential biological control agents found for fungal diseases of soybean
- Fungal diseases cause yield losses in soybeans and many other crops.
- A new study identifies viruses that affect important fungal pathogens, including some that are virulent and stable in the environment.
- Fungal viruses could be used to create biological control agents to kill pathogenic fungi and improve crop yield.
- Although the research focuses on fungal viruses affecting soybean, the results have implications for human health, as well.
URBANA, Ill. – Viruses are everywhere. They affect all forms of life, from complex mammals down to the mere fungus. We may not give much thought to fungal viruses, or mycoviruses, but new research from the University of Illinois suggests they deserve a closer look.
“There’s been a lot of work done with human and animal and plant viruses. There isn’t as much known about fungal viruses or insect viruses, because if they get infected with a virus, no one cares,” explains U of I and USDA ARS virologist Leslie Domier.
It turns out there are good reasons to care about mycoviruses. Fungal diseases account for approximately 10 percent yield losses annually in corn and soybean. When certain mycoviruses infect those fungi, they can become less virulent – good news for crop yields. These forms were the targets of a recent investigation by Domier and his colleagues.
“In addition to viruses that make fungi less virulent, we were also looking for those that might be transmitted outside of the fungus the way a cold virus is transmitted, where you can pick it up off a surface without having direct contact with another person. Therefore, we were particularly interested in viruses that were encapsidated, or that formed virus particles,” Domier explains.
The team extracted genetic material, DNA and RNA, from five major types of plant-pathogenic fungi and used computers to search for genetic sequences that resembled those of known viruses.
“We found a lot of sequences that were very similar to previously described fungal viruses, but we also found some encapsidated forms that were similar to plant viruses. Those were the ones we were most interested in, because they reduce fungal virulence and can be transmitted outside the fungus,” he says.
This key combination may make it possible for these viruses to be used as biological control agents. “Some mycoviruses have been shown in laboratory or greenhouse studies to be very effective biocontrol agents,” Domier says. One day, the encapsidated forms they discovered may be sprinkled on a field to kill pathogenic fungi and improve soybean yield.
Interestingly, the research could also improve medical treatment options for human fungal diseases.
“The biochemical pathways in fungi are relatively close to humans, so it’s often difficult to find something that will kill a fungus and not damage the person. Ultimately, we are hoping to explore whether we can use mycoviruses to reduce the severity of human disease to the point where normal immune response could clear the disease from the body,” Domier says.
The article, “Identification of diverse mycoviruses through metatranscriptomics characterization of the viromes of five major fungal plant pathogens,” is published in the Journal of Virology. The research was funded by the National Sclerotinia Initiative and the United States Department of Agriculture’s Agricultural Research Service.