Developing Tropical Maize as a New Biofuel and Forage Crop for Illinois (2010-2012)

Fred E. Below, Principle Investigator/ Department of Crop Sciences
Co PIs – Rajshree Agarwal, College of Business
Hans Blaschek, Center for Advanced BioEnergy Research
Dan Faulkner, Department of Animal Sciences
Jay Kesan, Department of Agricultural and Consumer Economics
Madhu Khanna, Department of Agricultural and Consumer Economics
Steve Moose, Department of Crop Sciences
Vijay Singh, Department of Agricultural and Biological Engineering
Gary Letterly, University of Illinois Extension, Christian County Unit

Tropical maize, a hybrid corn variety made by crossing temperate by tropical adapted parents, is a high energy crop yielding large amounts of biomass and stalk sugar with potentially valuable uses as both a forage for ruminants and as a biofuel crop, bridging the gap between current farmer needs and future energy requirements (see Figure 1). The crop provides value, flexibility, low risk to the producer, and minimal changes in agricultural practices. With these features tropical maize can readily be included in production rotations resulting in a large and positive impact on producers.

The objective of this project is to evaluate the value of tropical maize as a new forage and biofuel crop at a sufficient scale to enable its rapid adoption as a new multi-purpose commercial crop throughout Illinois and the U.S. We will investigate and demonstrate the economic and functional potential of tropical maize as a forage and a biomass crop by conducting field trials on a “pilot scale” size. Our current research of tropical maize has included genetic selection, optimization of nitrogen (N) requirements and crop management utilizing controlled experimental plots. We propose to expand plot size and utilize knowledge gained from our experiments to evaluate the most promising practices and varieties on a larger demonstration scale at the Dudley Smith Farm. This project will be implemented by a multidisciplinary team of University of Illinois – ACES faculty, two graduate students, local Extension staff, and a cooperating farmer-rancher.

We will identify a set of tropical maize hybrids and crop management factors that will optimize biomass yields and forage quality. We will directly assess the economic potential and energy efficiency for tropical maize as a biofuel feedstock and determine its value in cellulosic fermentation processes and as a solid pelletized thermal fuel, as well as its nutritional value for livestock. The project will also examine direct technology transfer of existing crop breeding, production and agricultural practices, equipment for planting, harvesting, storage and transportation and biomass processing for energy production. The outcome of this project will not only demonstrate crop growth and production, but will also utilize all aspects of our collected data to develop economic models, public policy analyses of federal farm program incentives and practical crop management guides. We will manufacture solid and liquid fuel from biomass, make seed on a large scale, and produce silage for feed trials. Community outreach and education programs will be conducted to further the goals of the Dudley Smith Initiative and expedite near term commercialization of tropical maize. The cumulative result will be a demonstration of the proof of concept for the commercial use of tropical maize as forage/silage crop and a reliable biofuel feedstock.

Research/Outreach Strategy and Objectives

The proposed project will span multiple years with the work plan for each year building progressively on data obtained from all aspects of the preceding year. We propose five interrelated aims, to be conducted concurrently in order to identify and mitigate potential barriers throughout the value chain, and utilize the multidisciplinary resources of our team to develop innovative solutions. Our primary objective is to transfer the knowledge gained from our current field experiments, being conducted throughout the state, to larger, “pilot scale” plots at the Dudley Smith Farm, to evaluate and demonstrate the potential for tropical maize as both a forage/silage crop and a dedicated energy crop.

Specific Aim 1 – Field Evaluation.

Three field production trials will be conducted concurrently, focusing on the targeted usage of the crop as either a bioenergy or forage crop. Tropical maize varieties selected for the first year field evaluation trials will be the best performing hybrids for biomass and sugar production from our current field trials, in subsequent years, a baseline variety will be used throughout the project for comparison to new high performing varieties, as selected from off site evaluation experiments conducted by the Below laboratory. The project will utilize up to twenty acres at the Dudley Smith Farm for evaluation and demonstration. A Christian County farmer will be contracted to do the necessary tillage, fertilizer and herbicide applications, planting and any other necessary operations the plots may require. Dr. Fred Below, PhD candidates, Mike Vincent and Wendy White from the U of I Crop Physiology Laboratory will oversee the plots, collect data and samples during the growing season. The proposed acreage for this project has been in continuous corn for several years and adds another factor to this project. Field trials will include the following activities to provide resource and production data as well as materials to be used for animal nutrition and biofuel suitability analysis, extract stalk sugar, conduct fermentation and ethanol production studies and manufacture solid fuel pellets.

Production of tropical maize plots to demonstrate the growth and yield potential under low and high N fertility, and provide large amounts of sample material for pelletizing, stalk juice extraction, liquid fermentation, and whole plant fermentation. Up to four tropical maize varieties, will be planted at the Dudley Smith Farm in plots up to 1 acre in size, for a total of 6-8 acres in all three years of the project. These hybrids will be grown under high N fertility common to Illinois grain production and low N fertility; allowing for multiple hybrid/N rate treatments. The high N rate treatment of the tropical maize will show the full yield potential and examine raising the crude protein level for animal feed applications. The crop will be planted with conventional equipment using the optimum plant population as determined by ongoing project work. Samples will be taken throughout the growing season to provide material for biofuel suitability, fermentation studies, stalk extraction and pelletizing. The pelletized solid fuel will be used at the local Christian County Extension office and closely monitored at all stages of production, harvesting and transport, processing and delivery, and storage and combustion as a furnace fuel, by Gary Letterly. Dr. Khanna will provide economic analysis. Additional studies that may be conducted include potential use of the field for grazing after frost, winter standability, equipment trials for harvesting and processing, and storage as new data is gathered each year of the study.

Samples will be collected throughout the growing season to evaluate the varieties for forage value (digestibility, crude protein, fiber, sugar) and bioenergy value (lignins, cellulose, sugar, and Btu). Based upon this information, the best performing tropical maize variety will be used in the following year’s plots and the feed trial. It is expected that in the final year of the study, we will identify tropical maize varieties best suited for each targeted use including biofuel, biomass and forage.

Produce and ensile tropical maize and conduct an animal feed trial demonstrating and comparing the feed value of tropical maize versus a conventional corn hybrid. Two ten acre plots will be bulk planted at the University of Illinois, Urbana, IL. One with a commercial grain hybrid and the other with the top tropical maize hybrid as determined from our N and management trials. The crop will be planted with conventional equipment using the optimum plant population and N level determined by ongoing work currently being conducted (2009 growing season). The plots will be harvested at optimal moisture for silage and stored in silage bags by Dr. Dan Faulkner’s lab. These bags work well for ensiling as there is little spoilage and consistent conditions for fermentation (Josefsson, Miquelon and Chapman). Samples of plant material will be weighed and sampled at this time to determine yield and raw nutritional value. The cured silage will be used in a silage feeding trial with 30-40 head of cattle. Dr. Faulkner and Mike Vincent will collect feed value and animal performance data from varied diets of ensiled hybrids.

Develop isolation plots to produce seed for subsequent year experimental trials. In order for tropical maize to become a viable component in Illinois crop rotations, it is necessary to develop the capability to produce seed locally and economically. Using data in each year’s trial, Dr. Moose and Wendy White will produce inbred parents in our off site nursery and then develop 2- 3 one acre isolation plots at the Dudley Smith Farm to produce hybrid varieties to be used in the project’s feed trials and biofuel production plots. The isolation plots will require a maximum of 10 acres in order to ensure appropriate isolation distances are maintained. The plots can be placed within existing plots used for soybean or other non-corn crops. Dr. Agarwal will provide assistance in analysis of the entrepreneurial potential for the production of tropical maize seed.

Collect data on inputs, biomass yield and composition of all hybrids. The Crop Physiology laboratory, (Mike Vincent and Wendy White) will collect pertinent data for each of the production trials. Samples to be collected for biofuel potential will include whole plants, pressed stalk juice (along with remaining residue), and dry ground tissue. The techniques of biomass sampling and analysis are well established by the Crop Physiology Laboratory. Stalk juice will be extracted with a portable research-scale press mill that uses a roller speed to extract stalk juice similar to a commercial sugarcane mill, and is designed to process plants quickly and efficiently. Samples to be collected for forage potential will include all above-ground plant material collected at several stages of development. This material will be chemically tested for nutritional feed quality by one of several commercial forage testing laboratories in Illinois, while other bulk samples will be ensiled for possible use in animal feeding trials.

Demonstration Plots for use in Field Days at the Dudley Smith Farm. Approximately a quarter to a half acre will be utilized to plant demonstration plots to be used for education and outreach activities during Field Days at Dudley Smith. The plots will be planted with conventional corn hybrids, silage hybrids and tropical maize hybrids. Two N rates will be used to exhibit a comparison of growth potential for each of the types of hybrids at varying N rates. These plots will be designated with appropriate signage and pertinent data.

Outcomes and Systems Payoffs

The outcome of this project will provide a valuation of tropical maize for forage, silage and fuel production (ethanol/butanol and solid pellets) and identify in three years the details that will facilitate the ready commercialization of tropical maize for both forage and biofuel production. Near term implementation of tropical maize is possible because there is a well established industry and infrastructure for support in corn production. Rapid advancements in corn genetics and technology can readily be made to improve the crop, existing seed and crop production methods for corn are directly transferable, equipment is readily available, agricultural practices are sociologically ingrained in the producers, and a marketing, distribution, supply and transportation infrastructure is already in place. Almost all aspects of the grain ethanol business model can be technologically transferred to tropical maize. The unique crop characteristics with both sugar and biomass make the crop a ready supplement to current ethanol processes and a premier candidate for the long range cellulosic production scheme.

Relevance to the Goals of the DSI.

This project represents an inter-disciplinary effort with a strong outreach component. The goal of this project is to generate information immediately useful to: 1) farmers considering low input high yielding biomass crops to be used for forage or on the farm energy, 2) other scholars working to evaluate, assess and optimize the biological potential of field crops with the needs of animal agriculture and influences of agricultural systems on natural resources and ecological and economic outcomes, and 3) policy makers whose programs determine whether and how practices and technologies are developed. A combination of integrated publication, demonstration, extension and outreach activities will be used to serve these different audiences.