Progress 09/15/01 to 09/14/04
Outputs
Lanceleaf sage was not competitive in wheat and only slightly competitive with soybean. Sage mortality was more than 80% at three of five study sites primarily due to wheat competition. Lanceleaf sage only affected soybean yield when sage emerged the same day as soybean, 6 kg/ha reduction for every g of sage wt per sq m (maximum of 14 bu/A). Sage that emerged 5 d or more after soybean did not affect soybean yield. Six crop rotations were initiated in 2002 to determine the impact of tillage, crop rotation, and herbicide combinations on Canada thistle (CT) densities. Crops included wheat, canola, flax, or fallow. Herbicide treatments included in-crop and pre-harvest applications. All rotations decreased CT densities greater than 98% in 2004 compared to initial densities in 2002. Treatments with fallow where tillage was the only weed control tool or less expensive herbicides like tribenuron + 2,4-D were as cost-effective or more than treatments with more expensive
herbicides. Any in-crop treatment followed by glyphosate applied pre-harvest reduced CT densities. The 3' ends of wild oat plastidic acetyl-CoA carboxylase (ACCase) have been sequenced from total RNA of seedling leaf tissue. Analysis using direct sequencing indicated the presence of Acc1;1 and Acc1;2, but not Acc1;3. It is possible that Acc1;3 is not expressed in the leaf tissue of seedlings, suggesting that the Acc1;3 locus may not be as important in herbicide resistance/susceptibility as Acc1;1 and Acc1;2. The 3' ends of these ACCase sequences are currently being cloned to clarify the identity of the expressed alleles. Foramsulfuron efficacy applied with a nonionic surfactant was enhanced the most by magnesium chloride followed by ammonium chloride. Magnesium chloride increased foramsulfuron efficacy when applied with low and medium HLB (8.7-13.3) secondary alcohol ethoxylate surfactants but was highly antagonistic with high HLB (17.4-18) surfactants. Foramsulfuron with magnesium
chloride retained more water than foramsulfuron alone or with surfactant. SEMs showed that foramsulfuron with magnesium chloride and surfactant formed a solid spray deposit without close epicuticular contact, which probably accounted for the antagonism. Wild World of Weeds Workshops were held in 2002 and 2003 where Weed Control Guides and Weed Control Research books were distributed to approximately 275 people each year. Media news releases, DTN, email list serve were also utilized to distribute information about invasive weeds. An NDSU Weed Science Web page (www.ag.ndsu.nodak.edu/weeds/) was developed to access to weed guide and other publications on invasive weeds.
Impacts
Incidence of lanceleaf sage in North Dakota has increased but numbers of plants in infested areas generally remain small. Lanceleaf sage has been observed in monoculture patches in fields but the reasons for this remain unknown. Sage has the ability to colonize and thrive in soil types common across North Dakota meaning that invasion into new regions is likely to continue. However, lanceleaf sage would not be likely to invade regions where cereals are the major crop grown. Chemical application to sage plants 5 cm or less is important to eliminate seed production. By the time plants reach 10 cm in height, sage is quite resilient to herbicide injury. Canada thistle densities can be reduced effectively with clopyralid in wheat or glyphosate pre-harvest. In the following years, a crop rotation that allowed use of specific herbicides with significant activity on Canada thistle reduced Canada thistle densities each year. This study showed that a three- or four-year period of
intense management can reduce high Canada thistle densities to manageable levels in cropland. An invasive weed identification and control web page was developed and has become very popular in the state and region (www.ag.ndsu.nodak.edu /invasiveweeds/).
Publications
- Bresnahan, G. A., F. A. Manthey, K. A. Howatt, and M. Chakraborty. 2003. Glyphosate applied preharvest induces shikimic acid accumulation in hard red spring wheat. J. Agric. Food Chem. 51:4004-4007.
- Breshahan, G. A., W. C. Koskinen, A. G. Dexter, and L. Cox. 2004. Sorption-desorption of 'aged' isoxaflutole and diketonitrile degradate in soil. Weed Res. 44:397-403.
- Carlson, M. G. and K. A. Howatt. 2002. Growth analysis of lanceleaf sage in four North Dakota soils. North Central. Weed Sci. Soc. Abstr. 57:120 [D: 2002 NCWSS Proceedings\abstracts\120.pdf]. North Central Weed Sci. Soc., Champaign, IL.
- Christoffers, M. J. 2004. Genetic diversity among weeds. p. 496-498. In R. M. Goodman, ed. The Encyclopedia of Plant and Crop Science. New York: Marcel Dekker, Inc.
- Howatt, K. A. and E. E. Dvorak. 2002. Mesotrione use in oat. North Central. Weed Sci. Soc. Abstr. 57:85 [D: 2002 NCWSS Proceedings\abstracts\085.pdf]. North Central Weed Sci. Soc., Champaign, IL.
- Dvorak, E. E., K. A. Howatt, and L. E. Del Rio Mendoza. 2003. Investigation of mucilaginous coating on lanceleaf sage seed. Proc. Western Soc. Weed Sci. 56:91.
- Dvorak, E. E. and K. A. Howatt. 2003. Oat response to mesotrione. North Central. Weed Sci. Soc. Abstr. 58:149 [D: 2002 NCWSS Proceedings\abstracts\149.pdf]. North Central Weed Sci. Soc., Champaign, IL.
- Li, Z., V. K. Nandula, and C. G. Messersmith. 2003. Contact activity of difenzoquat differs from that of paraquat. Pest Management Sci. 59:928-932.
- Mengistu, L. W., C. G. Messersmith, and M. J. Christoffers. 2003. Diversity of herbicide resistance among wild oat sampled 36 yr apart. Weed Sci. 51:764-773.
- Woznica, Z., J. D. Nalewaja, C. G. Messersmith, and P. Milkowski. 2003. Quinclorac efficacy as affected by adjuvants and spray carrier water. Weed Technol. 17:582-588.
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Progress 10/01/02 to 09/30/03
Outputs
Lanceleaf sage was not competitive in wheat and only slightly competitive with soybean. Wheat yield was not reduced and competition from wheat reduced lanceleaf sage biomass by 90%. Lanceleaf sage in soybean was influenced by interspecies competition, as sage population increased so did sage mortality with limited season long effect on yield. Leafy spurge control was improved when herbicides, Aphthona spp. flea beetles, and competitive grasses were combined compared to any treatment used alone. The greatest decrease came when imazapic was applied in conjunction with the flea beetles as leafy spurge stem density decreased from an average of 92 stems per square meter to only 7. In a greenhouse study, warm-season grass production was generally unaffected by imazapic while production of sideoats grama and switchgrass were reduced by 50% or more. Western wheatgrass, Canada wildrye, and green needlegrass tended to be reduced by imazapic. Direct sequencing of acetolactate
synthase (ALS) genes from two wild oat accessions with target-site resistance to ALS-inhibiting herbicides failed to reveal the presence of a resistance mutation. Target-site resistance in the wild oat accessions may be due to over-expression of ALS rather than an altered ALS enzyme. The effect of six crop rotations on Canada thistle density was evaluated over a 3 year period. Crops included wheat, canola, flax, and fallow. The optimum crop rotation was any that included an in-crop herbicide treatment followed by glyphosate applied preharvest. Canada thistle density was reduced by 98%. Weed control identification and control meetings were held state wide and a special Wild World of Weeds Workshop was held to present findings of these studies to the public.
Impacts
Incidence of lanceleaf sage in North Dakota has increased but numbers of plants in infested areas generally remain small. We found soil type does not restrict lanceleaf sage growth, so growers in all areas of the state need to be aware that a problem could develop and know how to manage this weed. Lanceleaf sage has established a strong presence in areas where more open-canopied crops such as sugarbeet and soybean are grown. Soybean acreage in North Dakota has increased five-fold in less than ten years, bringing with it more potential for lanceleaf sage encroachment. Wheat and other small grains are good crop options to help manage sage populations. Several meetings have been held to discuss lanceleaf sage management with producers.
Publications
- Carlson, M. G. and K. A. Howatt. 2001. Lanceleaf sage competition with hard red spring wheat and soybean. North Central Weed Sci. Soc. Abstr. 56:20 [D:\abstracts\020.pdf]. North Central Weed Sci. Soc., Champaign, IL.
- Janzen, L. A. and R. G. Lym. 2003. Biological control of purple loosestrife (Lythrum salicaria L.) with Galerucella spp. in North Dakota. Proceed. West. Soc. Weed Sci. 55: 88-89.
- Kegode, G. O. and M. J. Christoffers. 2003. Intriguing World of Weeds: Biennial wormwood (Artemisia biennis Willd.). Weed Technol. 17: 646-649.
- Pederson, S. N., M. J. Christoffers, and C. G. Messersmith. 2003. Identification of target-site point mutations among herbicide-resistant wild oat biotypes. Internat. Plant Animal Genome Conf. Abstr. P841.
- Mengistu, L. W., M. J. Christoffers, and R. G. Lym. 2003. A psbA mutation (valine 219 to isoleucine) in Kochia scoparia resistant to tebuthiuron, diuron, and metribuzin. GenBank. AY251265.1 and AY251266.1.
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Progress 10/01/01 to 09/30/02
Outputs
In-crop and pre-harvest herbicide treatments were applied in spring wheat to determine the long-term impact on Canada thistle densities. After the first year, clopyralid plus 2,4-D applied in-wheat reduced Canada thistle densities; whereas, Canada thistle densities increased following in-crop combinations of tribenuron, 2,4-D, fluroxypyr, or dicamba. Any in-crop application followed by glyphosate applied pre-harvest reduced Canada thistle densities. The effect of adjuvants on herbicides commonly used to control perennial broadleaf weeds was evaluated with particular emphasis on Canada thistle and leafy spurge. Tribenuron and imazapic efficacy were enhanced by including a nitrogen fertilizer source and both were generally most effective with a methylated vegetable oil adjuvant. Tribenuron efficacy was generally similar when applied with methylated vegetable oil or petroleum oil adjuvants. However, imazapic efficacy was not influenced by methylated vegetable oil or
liquid nitrogen fertilizer rate. A greenhouse experiment was conducted to examine relative lanceleaf sage growth in four North Dakota soils. Soil types were loamy sand, sandy loam, silty loam, and silty clay with a pH from 6 to 7.5. The sandy loam soil had the lowest pH and appeared to result in the largest plants but growth and development differences of lanceleaf sage among soils may not have biological implication. PCR primers were designed from the acetolactate synthase (ALS) gene sequence of Italian ryegrass (Lolium multiflorum Lam.) These primers were used to amplify the ALS genes of wild oat and were in turn used to directly sequence ALS genes from flucarbazone-resistant wild oat. The resulting sequence shared homology with ALS of other grass species and, as expected, demonstrated apparent polymorphism at several individual nucleotide sites.
Impacts
Several wild oat selections are resistant to herbicides like imazamethabenz due to enhanced metabolism of the herbicide. The enhanced-metabolism mechanism usually is not herbicide specific, which means that these wild oat selections may also rapidly metabolize new herbicides that may be introduced for wild oat control. Also, several wild oat selections have enzyme systems that are not inhibited by specific herbicides, which means there has been a mutation in the ALS enzyme. Thus, molecular biologists can study these selections to determine the specific mutations responsible for resistance. The incorporation of several control methods for leafy spurge has resulted in better long-term control in a variety of environments than single methods. Seeding of native species will help restore and stabilize the habitat rather than have one weed species replace another.
Publications
- Kava, J. A., D. R. Kirby, and R. G. Lym. 2002. Succession of mixed grass prairie after biological control of leafy spurge using Aphthona spp. flea beetles. Proc. West. Soc. Weed Sci.. 55:65-66.
- Kegode, G. O., M. J. Christoffers, M. L. Workineh, E. A. Nelson, and K. J. Mahoney. 2002. The increasing importance of biennial wormwood (Artemisia biennis). Abstr. Weed Sci. Soc. Am. 42:23.
- Mengistu, L. W., M. J. Christoffers, and G. O. Kegode. 2002. Genetic diversity of biennial wormwood. Artemisia annua internal transcribed spacers 1 and 2, complete sequences. GenBank Accessions AY131969 and AY131970.
- Mengistu, L. W., M. J. Christoffers, and G. O. Kegode. 2002. Genetic diversity of biennial wormwood. Artemisia biennis internal transcribed spacers 1 and 2, complete sequences. GenBank Accessions AY131967 and AY131968.
- Christoffers, M. J., M. L. Berg, and C. G. Messersmith. 2002. An isoleucine-to-leucine mutation in acetyl-CoA carboxylase confers herbicide resistance in wild oat. Genome 45:(in press).
- Christoffers, M. J., M. L. Berg, and C. G. Messersmith. 2002. Molecular analysis of acetyl-CoA carboxylase genes from herbicide-resistant and -susceptible wild oat: allele Acc1;3. GenBank accessions AF464875-AF464876.
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Progress 10/01/00 to 09/30/01
Outputs
The objectives of this research are: a) to develop integrated systems approaches for control of invasive weeds; b) to identify and contain newly discovered invasive and aggressive species including newly evolved herbicide-resistant genotypes; c) to understand the biology and ecology of aggressive weeds to establish ecologically based control methods; d) to evaluate the effect of integrated weed management systems on the native plant community, and e) to efficiently transfer information from these research projects to land owners and managers. An experiment to evaluate the combination of chemical, biological, and competitive grasses on leafy spurge control was established. Initial cover and density of vegetation present were evaluated, biological control agents were released, and seed bed preparations were made. Adjuvant development focused on the determination of annual plant species that respond similarly to herbicides and adjuvants as Canada thistle and leafy spurge
to decrease development time compared to growing perennials. Field plots were established to evaluate lanceleaf sage competition with wheat and soybean. Lanceleaf sage did not affect wheat growth or yield. Lanceleaf sage survival was as low as 6% in wheat and 45% in soybean. A wild oat accession with resistance to flucarbazone was identified and its mechanism of resistance determined to be a modified acetolactate synthase (ALS) enzyme. Resistance genes will be cloned using a plasmid vector and sequenced to identify the ALS mutation responsible for resistance to flucarbazone. A weed science extension web page has been created which will allow access to the results of this project.
Impacts
None to date.
Publications
- No publications reported this period
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