Location: Soil Management Research2009 Annual Report
1a. Objectives (from AD-416)
Objective 1: Identify and develop new and alternative crops and cropping strategies for the northern U.S. • Sub-objective 1-1. Identify best adapted species/genotypes of new, alternative, and traditional crops for biofuels and bioproducts production in northern climates. • Sub-objective 1-2. Develop innovative, and improve existing strategies for managing new, alternative, and traditional crops. • Sub-objective 1-3. Determine environmental limitations on growth, development, and seed oil and nutritional quality of new, alternative, and traditional crops. Objective 2: Develop new strategies and decision aids to improve and increase the efficiency of weed management. • Sub-objective 2-1. Develop biological models of important invasive and prominent weeds, stressing critical life history events. • Sub-objective 2-2. Develop and improve weed management models. • Sub-objective 2-3. Explore feasibilities of entirely new strategies of managing weeds, focusing on increasing research on biologically-based integrated weed management.
1b. Approach (from AD-416)
Two mutually supporting approaches will be taken to meet our objectives. The first involves a series of field studies to identify new (e.g. cuphea, pennycress, and bifora) and alternative crop genotypes (e.g. camelina and calendula), develop practices to manage them, and use these crops along with traditional crops to develop alternative strategies (double- and relay-cropping) to add innovative economic and environmental benefits. Additionally, controlled-environment and field experiments will be conducted to determine environmental limitations (e.g. water and soil and air temperature) to growth of new and alternative crops. The second approach involves the integration of field and controlled-environment experiments of weed growth and development, innovative weed control methods, and computer modeling to develop decision support aids to efficiently and effectively manage weeds in cropping systems that include new and alternative, as well as traditional crops. Together the outcomes of this research will provide clientele with new knowledge, crops, and management tools to increase cropping efficiency and diversity in northern climates.
3. Progress Report
Project personnel work on two primary issues: 1) identify new and alternative crop varieties, develop practices for managing them, and develop strategies to integrate these crops with traditional crops to add environmental and economic benefits; and 2) integrate weed growth and development data, innovative weed control methods, and computer modeling to develop decision support aids to efficiently and effectively manage weeds in cropping systems that include new and alternative, and traditional crops. Progress during this reporting cycle related to the first research issue include completion of an extensive regional field study to evaluate climate and soil environmental effects on growth, yield, and seed oil characteristics of several different cuphea genotypes. Cuphea is a new oilseed crop being considered as feedstock for military jet fuel. A grant funded by the Defense Advanced Research Projects Agency (DARPA) allowed us to employ a post doctoral research associate at Morris to help conduct this study, which involved an extensive network of collaborators including researchers from the Energy and Environmental Research Center at the University of North Dakota, North Dakota State University, University of Western Illinois, and USDA-ARS scientists from Ames, Iowa, and Peoria, Illinois. Extramural funding was also received from the National Sunflower Association through collaboration with North Dakota State University to initiate a study to determine physiological maturity of seed in three sunflower cultivars. Collaborative studies were also continued with Technology Crops International (TCI; a specialty seed company) to study the agronomics of calendula, an alternative oilseed that can be used as a replacement for volatile organic compounds (VOC) in paints and various other chemical products. Progress regarding the second research issue includes continuing research focused on identifying phenological events in the life cycles of weeds based on microclimate information. Through a CRADA, this research led to the development of software to help program the environmental conditions of plant growth chambers and incubators designed and made by a major environment-controlled chamber manufacturing company. Three new team-orientated weed research projects were initiated. One is in collaboration with several USDA-ARS researchers at their respective locations to examine the impact of rye cover crops on the timing and extent of weed emergence across a continent-wide climatic gradient. The second is a project in collaboration with the European Weed Research Society, Agriculture and AgriFoods Canada, the ARS unit at Urbana, Illinois, and Iowa State University to explore long-term seed dormancy, seedling behavior, and mechanical weed control of a single weed specie across 12 sites throughout Europe and North America. Thirdly, a project was initiated with scientists from Argentina, Spain, and other ARS sites to develop simulation models of weed seedling emergence of species that plague farmers in Europe, and South and North America. One manuscript from this work has already been submitted for publication.
1. Accurately predicting weed seed germination and emergence. Efficient and cost effective agricultural crop production is highly dependent on timely weed control, which often means applying the appropriate chemical or mechanical control practice at the proper stage of weed and/or crop development. Economic losses in the U.S. due to mismanaged weed control have been estimated in the billions of dollars. Our research team, which included a postdoctoral associate supported by extramural funding, developed computer software that helps predict microclimate factors such as soil temperature and moisture that, when used in conjunction with pre-existing weed seed germination models, allows the user to more accurately predict germination and emergence of certain weed species. The software is easy to use and can be used virtually anywhere in the world with simple user inputs of climate (maximum and minimum air temperature) and location. This will greatly benefit farmers by enabling them to better predict weed emergence and thus, plan ahead for appropriate weed control tactics and when to apply them.
2. Improving environment control of growth chambers. Often researchers want to perform an experiment in an environment-controlled chamber that simulates the environmental conditions of a particular region. Through research aimed at studying how microclimate factors affect weed growth and development, our research team developed software for Percival Scientific, Inc., a major manufacturer of growth chambers and incubators. The software, called WeatherEze, allows the user to set temperature, humidity, and light conditions that match the environment of any location on earth that has an on-line weather station. The research and development of WeatherEze was conducted through a cooperative research and development agreement (CRADA) with Percival Scientific, Inc. The features of WeatherEze now provide scientists and engineers greater flexibility in research (e.g., ecological adaptation and evolution) and product testing (e.g., fates of cosmetics) for different regions of the world using realistic microclimatic conditions.
3. Alternative weed control for organic producers. Few tactics exist for organic farmers to control weeds, especially without the use of soil tillage. Extensive soil tillage can have negative consequences such as erosion and emissions of carbon dioxide (a greenhouse gas) into the atmosphere. A new tactic was developed by our team that utilizes the grit of plant residues such as walnut shells propelled with a sand blaster to abrade (i.e., damage leaves and stems) weed seedlings in order to kill them. It was discovered that adequate control was achieved using this method, but effectively killing weed seedlings depended on their size at the time of treatment. As weed seedlings increased in size, the number of blasts from the sand blaster had to be increased to kill them (i.e., seedlings at the 2-, 4-, and 6-leaf stages were destroyed completely by 2, 4, and 10 blasts of grit, respectively). These results show that small weed seedlings potentially may be controlled non-chemically by abrasion from air-propelled grit derived from agricultural residues. The effectiveness of the technique still requires field verification, but if it is successful, organic farmers will benefit from a new weed control tactic.
4. Cuphea seed oil as feedstock for military jet fuel. A goal sought by the U.S. Department of Defense is to develop fuel for military aircraft derived from biological oils (e.g., plants, microbes and algae) produced in the U.S. to supplement or replace fuel made from petroleum, which is largely imported from foreign sources. Preliminary research done by the Energy and Environmental Research Center (EERC) at the University of North Dakota, one of our collaborators, indicated that cuphea, a new oilseed crop whose oil is rich in medium chain fatty acids, might make an efficient feedstock for producing jet fuel; however, little is known about the best climate and soil environments for producing cuphea throughout the U.S. as feedstock for biofuel. Research conducted by our team, funded by a grant from the Defense Advanced Research Projects Agency (DARPA), studied the potential of several different cuphea genotypes to be produced in the Corn Belt region as potential feedstock for JP-8 jet fuel. We discovered that two wild species, Cuphea wrightii and Cuphea lutea, adapted and flourish better over a wider range of climate and soil conditions than the semi-domesticated varieties PSR23 and HC-10. This information will help target best areas to grow cuphea as a potential biofuel feedstock and provide knowledge for breeders to improve crop performance. Through collaborative efforts with the EERC, it was shown that jet fuel derived from cuphea oil resulted in greater net energy efficiency (i.e., energy generated by the biofuel after subtracting the amount of energy required to make the fuel) than fuel made from vegetable oils such as soybean and canola. This information will help chemists and engineers to develop more efficient processes to convert bio-based oils to fuel.Forcella, F. 2009. Potential Use of Abrasive Air-Propelled Agricultural Residues for Weed Control. Weed Research. 49:314-345.