The market demand for woodland botanicals native to North America is rising. Because many of these herbs are harvested from wild populations, concerns for their conservation are also increasing. At the same time, a small but growing number of herb product manufacturers are requiring documentation that the raw material they purchase is certified organic, low in heavy metals, free of pesticide residues, contains a minimum specified level of bioactives, is traceable to its source, and has a voucher specimen. This provides a unique market opportunity for some farmers, particularly those with wooded acreages. With the exception of ginseng (Panax quinquefolius), however, little information exists on the commercial production and marketing of many of these plants. Markets are also unstable and the risks of producing these crops are great.

Joe-Ann H. McCoy

USDA-ARS, North Central Regional Plant Introduction Station, Iowa State University, Ames, IA 50011, USA

    The National Plant Germplasm System (NPGS) is a cooperative effort by public (State and Federal) and private organizations to preserve the genetic diversity of plants by long-term storage of germplasm, primarily in the form of seeds.

    The mission of NPGS includes: (1) the conservation of diverse crop germplasm through collection and acquisition; (2) conducting a variety of germplasm-related research; and (3) encouraging the use of the germplasm collections and associated information for research, crop improvement, and product development. Accession data is maintained via the Germplasm Resources Information Network's database (GRIN http://www.ars-grin.gov/npgs/). The accessions numbering 466,173 are represented in the NPGS as of 26 February 2006.

    The presentation will summarize how medicinal plant researchers can utilize the NPGS both for acquisition and long-term preservation of research collections. The collections are suitable for a wide variety of research projects ranging from ornamental breeding studies to LC/GC analysis of metabolites of interest. Examples of current research projects will be discussed. The Echinacea collection will be used as a model example of a comprehensive collection that has been preserved via the NPGS and is currently available for research purposes. Illustrations of seed and control-pollinated cage propagation methods, and facilities utilized for seed cleaning, testing, and storage will also be included. In addition, methods for utilization of the GRIN database to view evaluation data, locate passport information, and acquire germplasm will be provided.

Top of Page
 

Industrial Crops Session I (Meadowfoam)

Jerry Hatteberg

OMG Meadowfoam Oilseed Growers Cooperative &

Natural Plant Products, Inc., World Headquarters, Salem, OR 97302, USA

    The developing story of a new crop called "Meadowfoam" continues to achieve new levels of profitability and success. This wildflower native to southern Oregon and northern California was successfully bred into a commercially viable rotation crop for grass seed growers by Oregon State University. The unique oil removed from the seed is a broad-based functional ingredient for cosmetics that offers long-term stability. The potential environmental applications for this natural oil and the meal byproduct currently are being evaluated in several research studies.

    Introducing and successful launching a new crop such as Meadowfoam require several important and complex steps. It is a time consuming process that takes individual champions, patience, money, agronomic research, product development, money, technical research, regulatory acceptance, market studies, interested buyers, money, challenges from freeloaders, legal expenses, and a certain degree of luck. Meadowfoam has experienced all of these phases and has recovered from many of the associated pitfalls in the process. Grower profitability and confidence in the crop is are growing. as is, consumer awareness and demand.

    I will review recent Meadowfoam accomplishments by the OMG Meadowfoam Growers Cooperative and their marketing company Natural Plant Products in my presentation. Successful new crop development requires a wide range of important steps that will present very unique challenges before a profitable result is achieved.

R.J. Roseberg¹, J.M. Crane², T.W. Miller³, D. Putman⁴, and S.J. Knapp⁵

    Meadowfoam (Limnanthes alba Benth.) produces a very stable seed oil that has many unique properties. Meadowfoam is native to the Mediterranean climate region along the U.S. west coast from northern California to southern British Columbia. Because it is well adapted to poorly drained soils, cool, moist springs, and warm dry summers, research and commercialization efforts have occurred almost exclusively in Oregon’s Willamette Valley. Little is known about how changes in day length, climate, and other factors affect the performance of newer meadowfoam varieties, but these effects must be known if expansion in production is to occur beyond the current limited area.

    The objective of this study was to compare the seed and oil yield of two newer and one older variety at four locations along a north-south transect representing the range of meadowfoam’s native habitat within the U.S. west coast Mediterranean climate region.

    For two consecutive years, three meadowfoam varieties (Floral, Knowles, and OMF78) were planted on university research farms near Davis, CA, Medford, OR, Corvallis, OR, and Mt. Vernon, WA. Seeding rate was constant at all sites, but each site was managed by each cooperator using their best judgment and published guidelines regarding fertilizer, planting date, irrigation, and weed control. Bees were provided during pollination. As seeds reached maturity, all above-the ground material was cut, placed in fine mesh bags, and transported to the Corvallis site, where they were dried, threshed, and cleaned under uniform conditions.

In the first season, meadowfoam did not survive the winter at Mt Vernon, although it was not the coldest or wettest site. Seed yield, oil content, and oil yield were greatest at Corvallis, followed by Medford, then Davis. The number of seeds per acre was similar at Corvallis and Medford, but individual seed size was smaller at Medford. Knowles and Floral both had greater yield than OMF78 at Corvallis and Medford, but the reverse was true at Davis.

    For the second season, seed and oil yields were significantly higher at Corvallis, followed by Medford, then by both Mt. Vernon and Davis. Oil content was more uniform across sites in the second season, with Davis slightly greater than the other three sites. Seed size was greatest at Corvallis, but unlike the first year, seed size at Medford was the smallest of the four sites. Knowles had the greatest yield at all locations except Davis, where OMF78 had the greatest yield.

    Along a north-south transect representing the range of meadowfoam’s native habitat, the environment in the Willamette Valley seems to be optimum for production of meadowfoam seed oil. Commercial production may be possible in other regions, but it appears climate strongly affects the yield and quality of meadowfoam seed.

Tony Kavanagh

Peaks and Prairies, LLC, Malta, MT 59538, USA

    Oilseed producers have consistently struggled to generate acceptable returns for their crops. Commodity price scenarios play out constantly as the market surplus continues to be squeezed by the latest industry, biodiesel. Biodiesel manufacturers operate on thin margins and only become profitable due to scale. Efforts are always focused on reducing the feed stock costs, eliminating any possibility for agriculture producers to become profitable supplying this marketplace. Recent demand by the Federal government for biobased products became the focus of this project.

    The objective of our market research and product development was to identify and develop new value-added oilseed markets, which operated on and allowed higher margins, thus creating premiums on the oilseed feed stock, creating more value for the producer.

    Oilseeds and current technologies were researched to identify market channels in which competitive products could be produced and at a cost point acceptable to consumers. Research was undertaken in cooperation with Dr. Duane Johnson, Montana State University, Bozeman and the Biobased Institute to determine the suitability of various oilseeds in the lubricant markets, current demand, price points, product standards/certification, and manufacturability were all evaluated as well. Data provided indicated minimal success in the baser oil categories, with tough competition from low-priced petroleum products. Further research into advanced technology led to the discovery of USDA patented estolides, which converted the plant oils into a high performance lubricant base stock, competitive with current-day synthetics and manufacturability that was in line with the competitive pricing.

    Development of the estolide formulas as a motor vehicle lubricant was undertaken to initially determine operating thresholds for the various compounds and to identify the most promising cost effective formulation. Additional work was undertaken in cooperation with USDA-NCAUR to identify promising new oilseed crops such as Lesquerella and Cuphea, which offer additional beneficial lubrication properties helping extend the operating environment for the motor oil. Lesquerella offers many of the same properties as Castor and will be commercially produced this fall. The initial bench test results of the motor oil formulations have proven the suitability as a replacement to petroleum-based motor oil and estimated large scale manufacture costs appear in line, allowing us to compete head to head with current offerings.

    With the advent of the new Estolide technology in tandem with new oilseed crops such as Lesquerella and Cuphea, commercially viable, superior performing motor oils and other biobased lubricants will help reduce our foreign oil dependency and open new doors for agriculture.

Brooks Dailey

Montana Farmers Union, Great Falls, MT 59401, USA

    Farmers have been under increased strain to maintain profitability. Recently, the rapid rise in oil prices has affected the increase in costs associated with agricultural production. The prices of fertilizer, fuel, and transportation have caused producers to examine additional revenue sources still derived from the same land. This can be done by producers taking a greater role in value-added processing of the crops they grow through a business venture or a cooperative. The principles of a cooperative allow the farmer with limited risk capital to partner with others with the same vision.

    The objective is to describe avenues of new revenue to existing farmers by both traditional practices and new innovative means. Also discussed will be the connective corridor throughout the state that provides relevant information, educational material, and professional guidance needed due to the diversity of agricultural production, size of the state, and costs associated with new ventures.

    The Montana Cooperative Development Center and the Montana Agricultural Innovation Center both have as their mission statements to participate in the formation and direction of value-added agricultural ventures throughout Montana. The Cooperative Development Center utilizes a technical assistance network of eight people to assist in the formation of cooperatives. These cooperatives are formed in rural areas as defined by USDA-RD funding. The Montana Agricultural Innovation Center utilizes five resource centers in Montana to deliver services and beginning capital specific to value-added agriculture.

The Montana Cooperative Development Center model has continued to be funded by both Federal and State dollars. The services and Technical Assistance Network continues to expand. We have presented the Center as a model in other states. The Montana Agricultural Innovation Center started with a one year expected funding allowance, yet has continued for three years due to the Resource Centers maximizing resources and the support of industry leaders. The results have two main evaluation points. The decision of funding and professional guidance is provided based on the merits of the project as it launches. The other evaluation point is at the time the self-sustainability. The projects vary in scope and complexities as well as their success.

Value-added agriculture has matured and diversified as the costs and flat markets conditions continue to make commodity production less profitable. The use of both Centers complement each other as well as provide a stable platform with many resources for the producer. Examples of new agribusiness ventures in Montana will be given.

Bioproducts and Bioenergy, Session I

Kevin D. Kephart

Office of Research and Sponsored Programs, South Dakota State University, Brookings, SD 57007, USA

    Americans are becoming increasingly aware of the need for national energy security. Consequently, state and federal agencies are stepping up efforts to develop renewable energy systems that are sustainable and minimize negative environmental impacts. Many people recognize that agriculture has a role in addressing the nation's projected energy problems. Increased involvement of agriculture in production of non-food products raises many issues that will expand research and education from agronomists and environmental scientists. A joint study by the U.S. Department of Energy and USDA estimates availability of 1.3 billion tons of lignocellulosic feedstocks annually for conversion to energy. Additionally, these resources will be used to produce biobased products such as composites, lubricants, and construction materials. Public research and education have an important role to play as a massive re-design of our energy system develops. One effort in this regard has been underway since early 2001: the Sun Grant Initiative.

    The Sun Grant Initiative was authorized by Congress in January 2004 to broaden the role of land grant universities by implementing new programs on renewable energy and biobased industries. The missions of the Sun Grant Initiative are to (1) enhance national energy security through development, distribution and implementation of biobased energy technologies, (2) promote diversification and environmental sustainability of America's agriculture through land-grant based research, extension, and education programs in renewable energy and biobased products, and (3) promote opportunities for biobased economic diversification in rural communities.

    Regional Sun Grant centers include Oregon State University, South Dakota State University, Oklahoma State University, the University of Tennessee, and Cornell University. The regions will emphasize integrated research and educational programs on ag-based renewable energy and biobased industries.

The Sun Grant Initiative has developed recently to a program with support and engagement with three federal agencies. Funding through USDA-CSREES has been the foundation for establishing awareness during the initial years. Support from the U.S. Department of Energy - EERE has resulted in research on feedstock production, conversion technologies, educational programs, and gathering information to support policy development. Lately, funding through the U.S. Department of Transportation will launch Sun Grant research and education programs in each region.

VEGETABLE OIL DERIVATIVES AS MONOMERS FOR EMULSION POLYMERIZATION

Zhangqing Yu, Sharathkumar K. Mendon, Shelby F. Thames, and James W. Rawlins

School of Polymers and High Performance Materials, The University of Southern Mississippi

118 College Drive #10037, Hattiesburg, MS 39406, USA

    Waterborne coatings employ coalescing solvents to facilitate polymer particles with high glass transition temperatures to coalesce effectively and form smooth non-tacky films. However, these solvents evaporate during the drying process and constitute volatile organic compounds (VOCs). The use of vegetable oil macromonomers (VOMMs) as co-monomers in emulsion polymerization enables good film formation without the use of coalescing solvents. Moreover, VOMMs are derived from renewable resources and offer the potential of post-application crosslinking via auto-oxidation.

    To maximize the utility of renewable resources, it is imperative that VOMM incorporation into emulsions be at the highest levels possible. The inherent hydrophobicity of VOMMs poses challenges during emulsion polymerization, as the monomers do not migrate readily through the aqueous phase.

    In this study, the copolymerization of hydrophilicized soybean oil-based VOMMs with conventional monomers and the properties of the resulting latexes are discussed. Latexes with VOMM content as high as 80% were successfully synthesized. Interestingly, the VOMM latexes displayed low minimum filming temperatures that were independent of the glass transition temperatures (T_g). Thus, high T_g latexes formed smooth, glossy films at ambient temperatures without aid from coalescing solvents. Data from latexes formulated into coatings, and tested for properties as per ASTM standards are discussed. While latexes with the highest VOMM levels exhibited certain performance limitations, other VOMM-based latexes performed competitively against commercial latexes.

Mark. A. Smith

Lipid Biotechnology Group, National Research Council Canada. Plant Biotechnology Institute,

110 Gymnasium Place, Saskatoon, SK. S7N 0W9, Canada.

    World oilseed production for 2005/2006 exceeded 390 Million metric tons (MMT), yielding over 115 MMT of oil. The majority of this product was destined for use as edible oil and for food processing applications with only a small percentage entering the industrial market. The major non-food uses are currently for the production of soaps and detergents and conversion to biofuels.

    Almost all plant oils are triacylglycerol (TAG) oils. Their chemical structure gives them great potential as petrochemical replacements in a wide variety of applications ranging from fuel and lubricants to the manufacture of polymers, foams, and surface coatings. Vegetable oil, therefore, represents a very much underutilized renewable resource for industry. A number of factors, however, may place constraints on the large-scale acceptance of plant oils as industrial feedstocks. These include the limited repertoire of fatty acids synthesized by the major oilseed crop species, and the presence of a mixture of different fatty acids in a typical seed oil.

    Various approaches are currently being taken to improve the suitability of seed oil for industrial use. These include traditional plant breeding, accelerated by advances in genomics and high throughput analysis, and the genetic engineering of oilseeds to introduce novel traits. The challenges and opportunities in tailoring seed oil composition for particular purposes, and the development of new-engineered oilseed crops designed for industrial oil production will be discussed. Examples will include the manipulation of Brassica species to increase erucic acid content, and the production of unusual hydroxy fatty acids in oilseed crops.

Thomas A. McKeon, Xiaohua He, Grace Chen, and Jiann-Tsyh Lin

USDA-ARS-WRRC, Albany, CA 94710, USA

    Castor oil is an important industrial oil used to produce greases, lubricants, coatings, detergents, monomers for plastic production, plasticizers, and cosmetics. It is derived from the castor plant, a Euphorb Ricinus communis L. The oil is unusual in that the fatty acid component is 90% ricinoleic acid, 12-hydroxy oleic acid. Because the castor seed also contains a protein toxin and a potent allergenic protein, there has been considerable interest in developing an alternate source of high ricinoleate oil. However, in attempts to generate transgenic plants producing ricinoleate, researchers have found that the amount of ricinoleate produced is limited, even though the introduced hydroxylase gene is expressed at a high level. We have postulated that the castor seed has enzymes that direct the production and incorporation of ricinoleate into triacylglycerols.

    In an in vitro microsomal system, we have shown that ricinoleate is incorporated six-fold greater extent than oleate in the final step of oil biosynthesis, the acylation of diacylglycerol to triacylglycerol. There are several enzymes that can carry out this final acylation step. These are the acylCoA-dependent diacylglycerol acyltransferases (DGAT), types 1 and 2, and the phospholipid-diacylglycerol acyltransferase (PDAT). We have cloned genes for the two DGATs from developing castor seed and expressed them in yeast. In microsomes prepared from suitably transformed yeast, the DGAT type 1 shows a preference for acylating diacylglycerols containing ricinoleate. The DGAT type 2 shows very poor activity in the yeast expression system, similar to the finding of low activity for the Arabidopsis thaliana DGAT type 2 expressed in yeast. We have also cloned two genes from castor seed encoding acylCoA synthetases (ACS). One of these genes encodes an enzyme that shows preference for using oleate and other "hydrocarbon" fatty acids to acylate free CoASH, whereas the other ACS shows a threefold preference for using ricinoleate to acylate free CoASH. Taken together, the substrate preference of the DGAT type 1 and the ACS account for the sixfold preference we have observed for isolated castor microsomes incorporating ricinoleate into the triacylglycerol fraction.

Cindy Lowery¹, Dick Auld¹, Rial Rolfe², Tom McKeon³, and John Goodrum⁴

¹Plant & Soil Science Dept., Texas Tech University, Lubbock, TX 79409, USA

²Microbiology Dept., Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA

³USDA-ARS, Albany, CA 94710, USA

⁴Biological & Agricultural Engineering Dept., University of Georgia, Athens, GA 30602, USA

    Ricin is a protein toxin found only in mature castor (Ricinus communis L.) seed that enzymatically destroys the ribosomes of Eukaryotes. The presents of ricin in the high protein meal of castor has historically reduced its value as an animal feed. Because ricin has the potential to be used as a chemical warfare and bioterrorism agent, the production and processing of castor has undergone increased scrutiny by law enforcement and homeland security agents since the terrorist attacks of September 11, 2001. The production of castor cultivars with reduced levels of ricin would improve the economics of castor oil production, reduce the potential for accidental poisoning, and eliminate the potential of ricin being used by terrorist.

    Since 1994, Texas Tech University has been developing castor with reduced levels of ricin. The dwarf-internode cultivar, ‘Hale’ developed by Texas A&M University in 1970 was crossed with two Plant Introductions from the Soviet Union PI 258368 and PI 257654 that had been previously selected for reduced levels of ricin. In subsequent segregating generations, individual plants were selected for dwarf-internode growth habit and reduced levels of ricin and RCA120 using a radial immunodiffusion assay. In 2003, 12 F₈ lines were intercrossed to develop a synthetic population, and in 2004 and 2005, this population was screened for semi-dwarf-internode growth habit and lack of shattering. This experimental cultivar is currently being tested in Mississippi and Texas to compare it with the parental cultivar ‘Hale’. Despite the growing demand for castor oil for both historical markets and as a feedstock for biodiesel, domestic production of this new cultivar has been delayed by the lack of oilseed processors willing to address the potential concerns of state and federal agencies with responsibilities to Homeland Security.

COSMETIC ATTRIBUTES OF CUPHEA OIL

Lawrence A. Rheins, James H. Brown, John Hill, and Robert Kleiman

Floratech, 291 East El Prado Court, Chandler, AZ 85225, USA

    Trends in the cosmetic industry continue to lean heavily toward natural and naturally derived ingredients. Cuphea, grown in Minnesota and North Dakota, serves as the source of an oil with essentially no history of industrial use. The oil is rich in capric acid (65-75%) with smaller amounts of other short chain fatty acids. The oil also contains about 10% C18 unsaturated fatty acids.

    Floratech is developing this unique-botanically derived oil for use as a commercial raw material for the cosmetic industry. Mechanical and physical property tests reveal that the oil has similar properties to some commonly used raw materials such as mineral oil and caprylic/capric triglyceride. We have evaluated the response of this oil to oxidation along with the effect of other cosmetic compounds (e.g., sunscreens) as it specifically relates to oxidative stability.

    Cuphea oil has a medium to low spreading characteristic while having a low slip. These attributes are exactly what are needed for sunscreens that stay in place, providing requisite UV protection, yet providing desirable esthetic attributes of non-slippery or greasy upon application. Many low cost sunscreens already use mineral oil, and cuphea oil could be a suitable commercial substitute for this raw material. By coupling this information along with the fact that the oxidative stability of cuphea oil remains high in the presence of sunscreen actives, a strong fit for this ingredient in the highly visible cosmetic category is possible.

Studies are currently underway to evaluate cuphea oil derivatives and their potential role in other cosmetic categories (e.g., bath oil, lipsticks, and lotions/creams).

Top of Page

Horticultural/Agronomic Crops Session II (Fruits, Nuts, & Vegetables)

Y. Mizrahi¹, E. Raveh², E. Yossov¹, A. Nerd¹, and J. Ben-Asher¹

¹Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel

²Agricultural Research Organization, Gilat Research Station, D.N. Negev 85280, Israel

    With the aim to obtain new fruit crops that require minimum water, we started in 1984 to domesticate some species of cactus known in Latin America as pitayas. Four of these pitayas species are grown in Israel today as fruit crops, and the question that we currently ask ourselves is whether they really meet the expectation of having a water use efficiency (WUE) that is much higher than that of other fruit crops. We give the results of the only irrigation experiment of which we are aware that was conducted with the following vine cacti: Hylocereus undatus and H. polyrhizus known as red pitayas, and Selenicereus megalanthus known as yellow pitaya. For the fourth species, Cereus peruvianus, we give actual data on irrigation and yields based on the experience of farmers.

    The aim of the project was to test the effect of three water regimes [including water shortage treatment(s)] on growth, fruit yield and quality of the three new vine cacti crops, the yellow pitaya and the two red pitayas. The experiments were conducted in the Negev desert of Israel (annual precipitation of 200 mm/year; winter only). Plants were grown under shade nets (40% for red pitaya and 60% for yellow pitaya) and irrigated with ~160 mm irrigation/year (treatment A - control), ~80 mm irrigation/year (treatment B), or ~45 mm irrigation/year (treatment C), keeping soil moisture above -2.2 MPa. In pot experiments, water was withheld for three weeks while stem elongation continued until soil water potential decreased to -3.5 MPa (about 7% volumetric soil moisture), demonstrating the capacity of these plants to absorb water from very dry soils. Yields of shoots and fruit, and fruit quality were assessed for three consecutive years.

    Only treatment C showed significant reduction of yield and fruit size in the Hylocereus species, whereas in S. megalanthus the yield and fruit size were highest in treatment C. Absolute values of yield and fruit size for the yellow pitaya are much lower than the red pitaya and are not related to the irrigation treatments. Root exposures showed a very shallow root system up to 40 cm deep. Yields of red pitaya fruit fluctuated between 35 to 40 ton/hectare/year for which 1600 tons of water were used, i.e., for the production of 1 ton of fruits, 40 to 45 tons of water are required. For citrus, avocado, and mango grown in the same area 340 to 500 tons of water are required for the production of 1 ton of fruit. In practice, WUE for a C. peruvianus orchard (grown outdoors) is about 60 tons of water for production of 1 ton of fruit.

    In terms of horticultural production, fruit price per ton is also important. Taking into account that if accepted in the market, these new crops will acquire much higher prices than the common crops, hence their WUE is even higher in terms of income and profitability. We should realize, however, that the introduction of a new crop into the market remains a major problem.

Lee Reich

Lee Reich Ltd., New Paltz, NY 12561, USA

    The major fruit crops of temperate regions experiencing cold winters include the pome fruits and stone fruits as well as brambles, blueberries, strawberries, and grapes. The goal of the present research has been to identify a number of "uncommon fruits" that might expand this palate. Medlar (Mespilus germanica), cornelian cherry (Cornus mas), and alpine strawberry (Fragaria vesca) were once popular fruits that possess a number of qualities warranting their revival. Where climate is congenial and pest pressures low, juneberry (Amerlanchier spp.) and lingonberry (Vaccinium vitis-idaea) are worthy of commercial trials. Identification and development of suitable cultivars could bring American persimmon (Diospyros virginiana, perhaps as hybrids with Asian persimmons), gumi (Elaeagnus multiflora), maypop (Passiflora incarnata), and Nanking cherry (Prunus tomentosa) into the marketplace. Ribes spp. are popular in Europe and a century ago once increasing in popularity in the U.S.; new cultivars and increasing consumer awareness of the flavor and health properties of these fruits could make plantings again viable. And finally, pawpaw (Asimina triloba), hardy kiwifruit (Actinidia arguta, A. kolomikta), and shipova (X Sorbopyrus auricularis) are among those "uncommon fruits" adapted over wide regions and worthy of more extensive trial plantings today.

    The market potential of these uncommon fruits derives from their high flavor, their uniqueness, and their relative freedom from pest problems. With these qualities, such fruits would fit well into the rapidly expanding "organic" marketplace as well as upscale and ethnic markets. Uncommon fruits that handle poorly, such as pawpaw, alpine strawberry, and American persimmon, are well suited to those regions having potentially strong local markets either because of tourist influx or because of proximity to large metropolitan areas. Because of their relative freedom from pest pressures, all the "uncommon" fruits mentioned would be ideal for regions where increased suburbanization creates local markets, but also causes conflicts because of pesticide spraying.

    There is no perfect agricultural crop and research goals have been to highlight the strengths and the weaknesses, as well as research needs for each of the uncommon fruits with market potential.

W.F. Tracy¹, C. Vargas1, L. Zepeda², J.K. Pataky³, and M.A. Chandler¹

¹Department of Agronomy, Univ.Wisconsin-Madison, Madison, WI 53706, USA

²School of Human Ecology, Univ. Wisconsin-Madison, Madison, WI 53706, USA

³Department of Crop Sciences, University of Illinois, Urbana, IL 61801, USA

    Ustilago maydis the causal organism of common corn smut can cause economic losses wherever maize (Zea mays L.) is grown. However, the galls formed by U. maydis are edible and can be a more profitable crop than the corn itself. Huitlacoche (cuitlacoche), the Hispanicized version of the Nahuatl name for the edible galls, has been consumed by the people of Mexico since pre-contact times. The popularity of huitlacoche is increasing rapidly in the U.S., due both to the increasing size of the Mexican-American community and interest in new foods and fusion cooking, especially in high-end restaurants. The objective of this study was to determine the feasibility of adding huitlacoche to the product line of Troy Community Farm, an urban, non-profit CSA (community supported agriculture) farm.

    Sporidial suspensions were injected down the silk channel of unpollinated ears of maize. Ears were harvested 14 to 20 days after inoculation. Huitlacoche was marketed fresh on the ear still enclosed in the husks or as frozen galls that had been cut from the cob. We looked at the consumer acceptance of the different products, the consumer price, and whether huitlacoche production fit the farmer’s management system and business objectives.

    The Pataky and Chandler inoculation method was highly effective and gave good yields of galls. For the average farmer, there is a limitation in obtaining and culturing the inoculum. It is not a difficult process, but it is not part of most farmers’ standard techniques. When harvested at peak quality, as defined by flavor, the galls are highly perishable and delicate. At this stage, the galls are gray with a black interior and they split easily. The galls need to be consumed within a few days of harvest. Earlier harvest, when the galls are smaller with a grey interior, results in galls that can be removed from the ear either by plucking or cutting and freezing these galls. Freezing results in some loss of quality, but can be more attractive to chefs who have to plan menus in advance and require a dependable and consistent product. Pataky and Chandler estimated that based on an estimated price of $25 Kg-1, the value of huitlacoche harvested 15 to 17 d after inoculation ranged from $0.70 to $1.68 ear-1.

    While there was a receptive market for huitlacoche in the Madison area, huitlacoche did not fit the system of the Troy Gardens Farmer. This was primarily due to questions on availability of resources for inoculation and the highly perishable nature of the product. Farmers in the U.S. can successfully produce and market huitlacoche to meet the increasing demand; however, the technical and marketing requirements may make huitlacoche a better crop for a farm devoted to highly specialized crops.

James D. McCreight¹ and Jack E. Staub²

¹USDA-ARS, 1636 E. Alisal St., Salinas, CA 93905, USA

²USDA-ARS, Dept. Horticulture, University of Wisconsin, Madison, WI 53706, USA

    Melon (Cucumis melo L.) is a complex group of horticultural types long intertwined with mankind for a variety of purposes. Different types are known around the world and often engendering faithful supporters for their local melon as the best. Africa is the center of origin, but centers of diversity may be found throughout Asia and the Iberian Peninsula. Germplasm from the centers of diversity, particularly India, have been found to possess numerous genes for resistance to disease and insect pests of melon.

    Melons are known only as a fresh or lightly processed sweet salad or dessert fruit in many countries, but may be canned as fruit pieces or pressed juice, used for syrup, jam, or flavoring in baked goods. Dehydrated slices can be stored for short or moderate periods and reconstituted. Sour-sweet types are popular in the Middle East. Vegetable types dominate in regions of some countries, e.g., Rajasthan, India, but may be found in other countries such as Italy. Aromatic types, e.g., ‘Queen Anne’s Pocket Melon’ was once popular in the U.S. The ornamental types may be found in other regions of the world. The seeds are useful for their oil and protein, and may be lightly roasted and eaten as nuts.

    Formalized classification of the many melon types has been revised nine times since Naudin’s scheme in 1859. The two most recent revisions reflect the two approaches; one proposed six cultivar-groups, the other, which included examination of melons from central Asia, proposed 16 varieties in two subspecies.

    Molecular and phenotypic analyses of melon diversity indicate that remarkable genetic differences exist among geographic growing regions and cultivar-groups. Distinct differences exist between African melons and those from Spain, Central Europe, Mediterranean, U.S., and Asia, which are themselves dissimilar. These growing regions produce a delightful array of types differing in morphological characters. Numerous primary and secondary fruit skin colors and designs, shapes, interior textures and colors, flesh thickness, and sizes delight the eye, and form the genetic basis for the development of new market types. For instance, fruit flesh thickness ranges from nearly nothing to five or more centimeters, and occur with completely filled or large and empty seed cavities. Interior color can be uniformly orange, green, or white, or grading from one color to another. Moreover, the aroma ranges from nearly undetectable to highly aromatic and could be used to breed novel cultivars. The flesh can be bitter, tasteless, or highly sweet with a range of flavors from subtle to very pronounced.

    There are opportunities for new market types in each of the many existing markets both from introduction of existing horticultural groups and through breeding of novel types. Existing markets, however, largely dictate the types of disease and pest resistant melons that breeders develop and seed companies produce for growers. Thus, the development of new melon market types will require integration of plant breeding and marketing to create market environments where consumers are attracted to novel products.

James Nienhuis

Department. of Horticulture, University of Wisconsin,

Madison, WI 53706, USA

    Domestication in all crops continues, but in vegetables at a different, sometimes slower, sometimes faster rate. Many plants that were domesticated as vegetables in ancient times have been lost or replaced by vegetables that have been introduced. Some vegetables are evolving very slowly, likely due to constraints imposed by the narrow expectations and market demands of growers, processors, marketers, and consumers.

    Variation among cultivars is further constrained because many vegetables are introduced. Rather than developing variation among cultivars with adaptation to different growing environments, the trend has been to use cultural practices and choose locations to adapt the environment to the vegetable. Other vegetables are evolving more rapidly as other consumers are demanding and rewarding novelty in colors, shapes, sizes, and even flavors of traditional vegetables.

    The development of new vegetables is also occurring through selection and utilization of new tissues, e.g., garlic scapes rather than garlic bulbs. The vegetables that are considered new or novel are being developed through selection within the same families as traditional vegetables.

Top of Page
 

Ramu Govindasamy¹, Venkat Purduri¹, Richard Van Vranken², William Sciarappa², Albert Ayeni³, James E. Simon⁴, Frank Mangan⁵, Mary Lamberts⁶, Gene McAvoy⁶, and Kim Pappas¹

¹Agricultural Economics and Marketing, Rutgers University, New Brunswick, NJ 08901,USA

²Rutgers CRES, NJ Agric. Expt. Sta., Cook College, New Brunswick, NJ 08901, USA

³International Agriculture, Rutgers University, New Brunswick, NJ 08901, USA

⁵Dept. Plant, Soil & Insect Science, University of Massachusetts, Amherst, MA 01003, USA

⁶University of Florida, Homestead, FL 33030, USA

DIRECT MARKETING OF U.S. GROWN CHINESE MEDICINAL BOTANICALS: FEASIBILITY AND MARKETING STRATEGIES

J.M. Giblette¹ and C.A. Martin²

¹High Falls Gardens, Philmont, NY 12565, USA

²Sustainable Agriculture Research Center, New Mexico State University, Alcalde, NM 87511, USA

    In the 1990s, a boom followed by a decline due to market saturation in the herbal products industry resulted in losses to some U.S. farmers. To find more effective and profitable ways to market their herbs, grower associations in five different states formed a Medicinal Herb Consortium (MHC) to share information and develop strategies. In 2004-05, the MHC conducted a feasibility study and planning project for marketing domestically grown Chinese medicinal botanicals (CMB) directly to licensed practitioners of Acupuncture and Oriental Medicine (AOM) in the U.S. Project objectives were to combine existing and new market studies to assess the feasibility of direct marketing, to work with AOM practitioner groups to identify opinion leaders and develop direct marketing relationships, and to determine if herbs grown in different regions could provide an acceptable product mix for the AOM market.

    To gather information and attract AOM practitioners, interviews and informal surveys were conducted, events were staged to show samples, articles were published in professional and trade journals, and presentations were made at practitioner conferences. The results can be summarized as follows:

1. A. A clearly defined market segment served by established educational institutions, product sources, and distribution channels could be identified. Practitioners graduated from accredited AOM colleges, which train herbal practitioners using whole plant parts imported from China, were able to differentiate sensory characteristics of imported and domestic herbs. Presented samples received the most favorable response of all project activities and indicated that direct marketing of fresh and fresh-dried herbs as a new product category was possible and could justify higher prices.

2. B. A well organized AOM profession exists as a cost-effective market. While imports can be expected to dominate the market as practitioners become familiar with the quality of domestic fresh herbs, increases in market share for domestic CMB depend on long term relationships established among farmers and AOM practitioners, including students and representatives of AOM organizations and educational institutions.

3. C. A conclusive preference for domestic herbs grown in different regions proved to be beyond the scope of this project. Regional variations were, however, an asset that could be used advantageously to stimulate comparisons of herb quality, attract practitioners, and encourage support of local production.

    Future marketing by the MHC will feature a "pull" strategy designed to use educational activities to build demand for domestically grown CMB within the AOM profession. Evaluation of products by colleges, clinics, and individual practitioners will be supported by the sale of sample packs containing a collection of several herbs in small quantities.

D.M. Modise, K.K. Mogotsi, E.B. Khonga, and S. Machacha

Crop Science and Production Department, Botswana College of Agriculture, Gaborone, Botswana

    The Basarwa (Bushmen) of Botswana collect and consume the Kalahari Desert truffle (Kalaharituber myces) annually at the end of the rainy season. As with other mushrooms, the truffles (fruiting bodies) are nutritious with relatively high amounts of proteins, fats, carbohydrates, minerals, crude fibre, and vitamins. The collected truffles are generally sold without consideration of the size (diameter), but weight is the preferred method of measurement of the crop.

    This study was carried out to determine the sizes of the truffles that exist in the Kalahari, and also to establish the relationship between the size and nutritional content. Thus, the optimum truffle size could be established and pricing would eventually reflect the size of the crop. This would be particularly important where the crop is collected for export.

    About one ton of truffles was collected from a geo-referenced site in the Kalahari Desert. These were sorted and replicated according to size and batches. Other parameters that were recorded include fresh and dry weight and the nutritional content of the truffles of the various group sizes.

    There were five grades or sizes of truffles with the heaviest truffle weighing about 0.5 kg and the lightest weighing only 25 g. The macronutrient (Na, K, P, and N) concentration was not significantly different among the five different sizes or weight of the truffles. The micronutrients (Cu, Zn, and Mn) were also not significantly different in the five different groups of sizes, but iron (Fe) was significantly higher for the smaller-sized truffles up to the second small- sized ones.

On the whole, there appears to be very little differences in nutritional content parameters that were measured between the small- and the large-sized truffles.         Therefore, it may not be necessary to export the large sized truffles because there is no real extra benefit that may be gained nutritionally.

The size of the truffles would presumably also have a bearing on the costs of packaging and shipping of the produce to far destinations.

Susana Fischer¹, Luis Inostroza¹, Rosemarie Wilckens¹, Marisol Berti¹, ²,

Marcelo Baeza³, and Edgar Pastene⁴

¹Departamento de Producción Vegetal, Facultad de Agronomía, Universidad de Concepción, Casilla 537, Chillán, Chile

²Present address: Department of Plant Sciences, North Dakota State University, Fargo, ND 58105, USA

³Departamento de Botánica, Facultad de Ciencias Naturales y Oceanográficas, Chile

⁴Departamento de Farmacia, Facultad de Farmacia, Chile

    About 44.6% of the Chilean plant species are endemics, and therefore, they constitute a unique and exclusive genetic heritage in the world. Most of these are main components of indigenous herbolarium and their uses in popular medicine are presently recognized, and therefore, are in constant demand. One of these is Geum quellyon Swee used by Mapuche Amerindians herbolarium due to the supposed properties, among them, principally, as an aphrodisiac. Others confer the plant with antioxidant properties in vitro, although it still remains unknown in its in vivo potentiality. In Chile, information is unavailable about the behavior of G. quellyon. Thus, the anthropologic intervention and indiscriminate cultivation of endemic and native species represent a constant threat to its diversity and ecological balance.

    The objective of this work was to study seed germination, phenology, and chemical and molecular characterization in two populations from different altitudinal distribution (1200 and 200 m above sea level). The assays and evaluations were performed in two G. quellyon populations collected at the 8th Region, Chile, growing in greatly different hydric environments. Significant differences were observed in the maximum germination of seeds from both G. quellyon populations and could be an adaptive consequence of accessions. Optimum germination temperature was 23.3°C, and minimum and maximum temperature were 6.5 and 38.5°C, respectively. In relation to the phenology under crop condition and chemical characterization, both populations differ in phenological behavior. They also showed differences in total polyphenol concentration, expressed as Gallic Acid Equivalents. Both G. quellyon populations have 2n = 42 chromosomes, with size < 3 μm so that the populations from the 8th Region do not present difference in ploidy level. The DNA isolation and its amplification were performed. Fragments of approximately 400 bp were analyzed for genetic diversity.

    There are differences in germination as in phenological behavior in G. quellyon growing at 1200 and 200 m asl. Moreover, there is evidence of accumulation of different concentrations in total polyphenol patterns, which justify evaluating responses to stress.

Ramu Govindasamy¹, James Simon², Venkat Purduri¹, Juliana Asante-Dartey³, Hanson Arthur³,

Bismarck Diawuo³, Dan Acquaye³, and Nicholas Hitimana⁴

¹Agricultural Economics and Marketing, Rutgers University, New Brunswick, NJ 08901, USA

²New Use Agriculture & Natural Plant Products Program, Rutgers University, New Brunswick, NJ 08901, USA

³P.M.B. (18) Kanda, Accra, H/NO C 205/29, Mempeasem, East Legon, Accra, Ghana

⁴Nicholas Hitimana, ASNAPP Rwanda, PO Box 6052, Kigali, Rwanda

Alice L. Pilgeram¹, David C. Sands¹, Mathew M. Kirkpatrick¹, Brian M. Thompson¹,

Quinn Bloom¹, Darrin L. Boss², Duane L. Johnson³, Edward Dratz⁴,

Frederick T. Barrows⁵, and Nick Dale⁶

¹Montana State University, Plant Science and Plant Pathology, Bozeman, MT 59717, USA

² Montana State University, Northern Ag Res. Center, 3848 Fort Circle, Havre, MT 59501, USA

³Montana State University, Northwestern Ag Res. Center, 4570 MT Hwy 35, Kalispell, MT 59901, USA

⁴Montana State University, Chemistry and Biochemistry, Bozeman, MT 59616, USA

⁵USDA Fish Technology Center, 4050 Bridger Canyon Road, Bozeman, MT 59715-8713, USA

⁶University of Georgia, Poultry Science, Athens, GA 30602-2772, USA

    Camelina (Camelina sativa) is a plant containing valuable oil, fiber, and high quality protein with many potential uses in both nutritional and industrial applications. This crop can be economically produced throughout Montana providing a much-needed high-value crop with relatively low input costs for Montana producers. The oil can be used to produce biodiesel. The low input costs of camelina enable production of economic oil for biodiesel manufacture without sacrificing profitable farmgate. However, camelina oil is also a rich source of both omega-3-fatty acids (α-linolenic acid (~40%)) and the antioxidant gamma tocopherols. The oil can be used to produce high value foods and cosmetics. The meal can be fed to livestock for production of high omega-3 meats, eggs, and dairy products.

    The objective of our camelina research was to evaluate the oil and meal as food and feed ingredients. Cold-extracted camelina meal has a residual oil content of 10 to 13% and contains >40% protein. This meal has been evaluated as a feed ingredient for the production of egg, goat milk, beef, turkey, dog, and fish. Beef, poultry, dog, and goat show normal weight. Feed rejection has not been observed. The fatty acid profiles of beef, egg, and goat milk were analyzed using GC-MS. In all cases, the camelina meal shows promise as being a high protein diet ingredient competitive with soy protein. Camelina- fed beef and milk from camelina-fed dairy goats contain increased levels of omega-3 fatty acid. The omega-3 content of egg is also increased in chicken fed camelina diets.

    Future research is focused on optimizing camelina-feeds for maximizing omega-3 content in meat, eggs, and dairy. Initial trout feeding trials showed promise. However, in larger trials, fish rejected feeds that contained camelina meal, but did not reject feeds containing camelina oil. Camelina oil is being tested as cooking oil in baked products (bread), salad dressings, and spreads (peanut butter). The potential market for camelina-based food ingredients appears strong given the current interest in omega-3 foods.

Marisol Berti¹, Burton Johson¹, Russ Gesch², and Frank Forcella²

¹Dept. of Plant Sciences, North Dakota State University, Fargo, ND 58105, USA

²USDA-ARS, North Central Soil Conserv. Res. Lab., Morris, MN 56267, USA

    Cuphea (Cuphea viscosissima Jacq. x C. lanceolata W.T. Aiton, PSR23) is a new oilseed crop being developed in North Dakota and Minnesota that has oil rich in medium chain fatty acids. Progress has been made on improving cuphea agronomically, but little is known about nitrogen fertility requirements for cuphea production.

    The objective of this study was to determine the optimum nitrogen application rate for maximizing seed yield and oil content. The experiment was conducted at Casselton and Carrington, ND, and Glyndon and Morris, MN in 2005. The experimental design was a randomized complete block with four replicates. Treatments (soil + fertilizer N) were 0, 60, 80,100,150, and 200 kg N ha-1 at Casselton and Glyndon; 0, 50, 90, 150, 200, and 250 kg N ha-1 at Carrington; and 0, 40, 80, and 120 kg N ha-1 at Morris.

    Measurements included plant nitrate content at three plant developmental stages [sampling date (1) 7/13 - 7/27, (2) 8/4 - 8/10, and (3) 8/31 - 9/12], seed and biomass yield, 1000-seed weight, oil content, and total plant and seed nitrogen content.

    Plant nitrate content decreased from the first to the last sampling dates at all locations. Plant nitrate content at all sampling dates was significantly higher for the treatments with greater than 90 kg N ha-1 at Carrington. Plant nitrate content at Morris at the last two sampling dates was higher for nitrogen treatments of 80 and 120 kg N ha-1.

    Seed yield was influenced by nitrogen treatments only at the Glyndon location where the highest yield (270 kg ha-1) was obtained with 100 kg N ha-1. Seed yield varied among locations with the highest yields at Morris ranging from 503 to 583 kg ha-1.

Biomass yield, 1000-seed weight, oil content, and plant total nitrogen content were not affected by the nitrogen treatments at any location.

Seed nitrogen content was affected by nitrogen treatments only at the Casselton location where higher seed nitrogen content (2.74 to 2.89%) was determined for nitrogen treatments from 80 to 200 kg N ha-1, compared with the check treatment that produced the lowest seed nitrogen content (2.65%). Cuphea total nitrogen absorption fluctuated between 69 and 83 kg N ha-1 at Carrington, 129 and 171 kg N ha-1 at Casselton, and 83 to 147 kg N ha-1 at Glyndon.

    Accordingly, N fertility appears to have little influence on seed yield, and aboveground biomass, values of which were quite low for the former two variables, and relatively high for the latter. Consequently, the possibility arises that another soil nutrient may be limiting cuphea's ability to convert aboveground biomass to seed yield.

A.D. Pavlista, D.D. Baltensperger, and E.L. Nielsen

Department of Agronomy and Horticulture, University of Nebraska,

Scottsbluff, NE 69361, USA

    Oilseed crops are used mostly as a food staple and for industrial oils. With increased emphasis and demand for diesel substitution, acreage of brown mustard (Brassica juncea), canola (B. napus), and camelina (Camelina sativa) as biodiesel is anticipated to increase in the High Plains. The objective of this study is to elucidate the phenology of these crops in the western Nebraska and their adaptation to spring planting dates with the intention of developing a growth model for growers.

    A field trial was conducted in 2005 on these crops to study their phenology after planting on 25 Feb, 22 Mar, 8 Apr, 26 Apr, and 6 May. Each was grown in replicated, randomized plots measuring 4.6 m long by four rows spaced 0.3 m apart. Phenology measurements of developmental stages were taken periodically. For brown mustard, canola, and camelina, the first date in late February had the longest emergence interval, and except for canola, the lowest stand. Canopy height was not affected. Flowering for these crops occurred earlier with the earliest date and occurred later as the planting date was delayed. However, the maturity date was the same regardless of planting except for camelina, which matured earlier with earlier planting. Bird damage occurred in brown mustard and was greatest with the earliest planting and least with the last planting. Yield was lowest with the first planting date. For brown mustard and canola, yield was highest in the later planting dates, but for camelina yield was highest with the late March and earlier April dates that averaged over all three crops gave the best yields.

    On 6 May, additional plots were seeded to obtain growth data from sampled plants. Four to six plants were removed after 4, 6, 9, and 12 weeks after planting (WAP), and their length as well as the weights of plant parts were taken. For all crops, canopy height and width peaked 8 WAP and 9 WAP, respectively. Stem length continued increasing to 12 WAP, just before harvest, reaching lengths of 169, 185, and 115 cm for brown mustard, canola and camelina, respectively. From 4 to 9 WAP, fresh weight accumulated 1.9, 4.5, and 0.8 g/wk for brown mustard, canola, and camelina, respectively. At 9 WAP, fresh and dry weights were shifting from vegetative to reproductive structures, and between 9 and 12 WAP, pods were increasing in dry matter, whereas stem dry matter was decreasing.

    These trials were repeated in 2006 and the accumulated data will be used to develop a model to predict growth and development patterns of brown mustard, canola, and camelina for biofuel production in the High Plains. Related date-of-planting studies are being conducted in other states in this region.

Rogers E. Harry-O’kuru

New Crops and Processing Technology Research Unit, National Center for Agricultural Utilization Research,

USDA-ARS, 1815 N. University Street, Peoria, IL 61604, USA

    Sicklepod (Senna obtusifolia L) is an invasive weed species especially of soybean and other field crops in the southeastern United States. The seed contains a small amount (5-7%) of a highly colored fat as well as anthraquinones, proteins, and galactomannan polysaccharides. The character of sicklepod seed oil is such that a small amount of the weed seed present in a soybean crush lowers the quality of the soybean oil. Although cultivation of "Round-up-ready soybeans" mitigates infestation of the crop by sicklepod, the latter is so prolific that even volunteer stands yield >1000 lb of seed per acre. The right thing to do under this circumstance is to tap the potential of this weed as an alternative crop in the affected region.

    In earlier laboratory-scale work, we have shown the feasibility of separating the different components of sicklepod seed. At the kilogram-level and higher processing quantities, however, exigencies have arisen leading to modification of the approach in order to separate effectively components of the defatted seed meal. In one version for cleanly separating the proteins, the dried petroleum ether defatted meal was extracted with 0.5 M NaCl solution to remove albumins and globulins; then with 80% ethanol, prolamins were extracted from the pellet from the salt extraction. Glutelins were removed from the residual solids with 0.1 N alkali leaving the polysaccharides. In a simpler (pilot-scale) version for the polysaccharides, several kilograms of the dried defatted meal were stirred into deionized (DI) water for 30 to 40 min, and then pumped into the centrifuge. The resulting centrifugate (supernatant) was removed and stored. The residual cake was resuspended in an equal volume of DI water as described and centrifuged again. The pooled supernatants were heated to 92°C (15-20 min), filtered, cooled to room temperature, and passed through a column of Amberlyte to obtain the polysaccharides after freeze-drying or spray-drying the eluate solution.

M.A. Foster¹, D.A. Dierig², and M.J. Wintermeyer²

¹Texas A&M University Agricultural Research Station, Pecos, TX 79772, USA

²USDA-ARS, U.S. Arid Land Agricultural Research Center, Maricopa, AZ 85239, USA

    Several herbicides are registered under Special Local Needs (24c) [SLN] in Arizona and Texas for weed control in lesquerella. Trifluralin provides adequate preemergence control of annual grasses and broadleaf weeds, fluazifop controls annual and perennial grass weeds postemergence, and oxyfluorfen is used for postemergence control of annual broadleaf weeds. This program has worked well in establishing large blocks of lesquerella, but the postemergence control of broadleaf weeds is still a major concern. Treatments that offer a broader spectrum of control, and that are more cost effective than oxyfluorfen are needed. The objective of this research was to determine the tolerance of lesquerella seedlings to alternative postemergence herbicides versus the SLN treatment: oxyfluorfen (0.6 kg ai/ha).

    Our study was initiated 20 October 2005 at the University of Arizona Maricopa Agricultural Center, Maricopa, Arizona. Trifluralin (1.1 kg ai/ha) was applied preplant on an 8 ha block, and advanced generation lesquerella seed was planted on level basins with a Brillion seeder at 11 kg/ha and border irrigated. Herbicide treatments consisted of plots (6 m long and 3 m wide) arranged in a randomized complete block design with three replications. The following postemergence herbicide treatments were applied at 1/2x, 1x, and 2x rates on 5 December 2005 when the lesquerella seedlings were in the 4 to 6 true leaf stage: benoxacor (2.0, 3.0, 4.0 kg ai/ha); clopyralid (0.30, 0.60, 1.10 kg ai/ha); dicamba (0.07, 0.20, 0.30 kg ai/ha); oxyfluorfen (0.30, 0.60, 1.10 kg ai/ha); oxyfluorfen+clopyralid (0.20+0.20, 0.30+0.30, 0.60+0.60 kg ai/ha); and pyrithiobac (0.03, 0.07, 0.12 kg ai/ha). The treatments were applied using a CO²-powered backpack sprayer with a four-nozzle boom (Teejet 8004 flat fan nozzles) delivering 225 L/ha at 187 kPa. Lesquerella seedling density was determined before spraying in each plot by counting the seedlings in a 0.25 m² quadrat. Counts were made weekly for 90 days and plant mortality was determined by the percentage change in seedling numbers. Seed production was measured in June 2006 by harvesting a 6 m by 2 m strip in each treatment with a Hege 180 combine.

    Plant mortality was 100% in all pyrithiobac treatments. Mortality was only 3% in the 1x oxyfluorfen plots and 0% in the cloypralid and oxyfluorfen+clopyralid treatments, respectively. Seed production was greatest in the 1x treatments of oxyfluorfen (1,187 kg/ha), clopyralid (1,160 kg/ha), and oxyfluorfen+cloypyralid (1,195 kg/ha) treatments. The 1x oxyfluorfen treatment would cost $56/ha, versus $98 and $77/ha for the 1x clopyralid and oxyfluorfen+clopyralid treatments, respectively. Oxyfluorfen is still the leading postemergence treatment for weed control in lesquerella.