Progress 05/01/10 to 04/30/15
Outputs
Target Audience:Producers, Cooperative Extension personnel, Scientists, Plant Breeders, and Agricultural Industry representatives. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?An undergraduate student was mentored on the use of molecular markers to identify herbicide resistance. How have the results been disseminated to communities of interest?Multiple outlets have been utilized to disseminate the results of this project. The primary means of dissemination are through grower meetings throughout the state. The results were presented at 23 grower meetings over the span of the project. The results were presented at multiple scientific meetings, including the Weed Science Society of America, the Western Weed Science Society, and the Washington State Weed Association. An extension bulletin was also submitted incorporating the results of the project. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Prickly lettuce (Lactuca serriola L.) is an invasive weed with air-borne seeds that crosses boundaries at multiple scales - from field borders to regional boundaries. Prickly lettuce has become a widespread and troublesome weed in the PNW. It occurs in all rainfall zones and is difficult to control largely due to ALS resistance but also due to increased tolerance to 2,4-D and glyphosate. It infests conservation reserve program (CRP) land and appears to cause significant economic losses in wheat-based cropping systems, particularly in pulses. The objectives were: 1) Study the biology of prickly lettuce, focusing on weedy traits including herbicide resistance; 2) Determine prickly lettuce recruitment and seed rain in response to typical and effective CRP weed control inputs, 3) Determine prickly lettuce interference in winter and spring wheat. Work focused on understanding prickly lettuce biology with an emphasis on herbicide resistance and important weedy traits. Since the introduction of acetolactate synthase (ALS) inhibitor herbicides in the 1980's, the number of ALS-resistance weeds species has increased rapidly, and ALS-resistant biotypes outnumber resistance to other herbicide modes of action. Twenty eastern Washington prickly lettuce biotypes from across the region were grown in a greenhouse and treated with multiple ALS-inhibiting herbicides. In conjunction with the greenhouse study, ALS mutations were studied by extracting DNA from the 20 biotypes and amplifying the nucleotide sequence containing domain A in each the ALS gene. Known amino acid substitutions in the ALS gene of resistant biotypes were observed - the originally observed Pro197His substitution and a novel (to North America) Pro197Thr substitution. Cross resistance patterns to ALS-inhibiting herbicides confirmed the nucleotide substitutions. The results of this study confirm point mutations within the ALS gene of prickly lettuce in North America. In wheat fields near to Pullman, WA, several individual plants within a prickly lettuce population were observed to survive two separate broadcast applications of a glyphosate plus 2,4-D in mixture. Consequently, seed were collected from the surviving plants to determine the level of resistance to 2,4-D. The objectives of this study where to identify to the determine response of putatively resistant prickly lettuce biotypes to increasing rates of 2,4-D and to investigate the mechanism of resistance. In dose response experiments, the GR50 for susceptible prickly lettuce was 8 and 9 times less than the field-collected biotype and its progeny, respectively. The resistant prickly lettuce biotype was found to be 27-fold more resistant to 2,4-D than the susceptible biotype based on regrowth of the resistant biotype. The resistant prickly lettuce biotype is cross-resistant to MCPA and dicamba, but not to aminopyralid, clopyralid, or fluroxypr. To determine the mechanism of resistance, absorption and translocation studies using 14C-2,4-D were conducted on the suspected 2,4-D resistant biotype and a known susceptible biotype. At 96 HAT, resistant and susceptible biotypes absorbed 33.8 and 42.7% of applied 14C-2,4-D respectively and out of the total herbicide absorbed, 74.5 and 70.1 % remained within the treated leaves of resistant and susceptible biotypes, respectively. At 96 HAT, the total amount of radioactivity translocated from the treated leaf to different plant parts was similar in both biotypes (25.5 and 29.9% for resistant and susceptible biotypes, respectively). However, 23% less 2,4-D was translocated to the crown of resistant biotype compared to susceptible biotype. Re-growth of resistant prickly lettuce biotypes commonly occurs from apical or lateral meristems located in the crown. Reduced herbicide translocation to the crown in resistant biotypes could be, in part, a mechanism for 2,4-D resistance in prickly lettuce. Crosses were completed to investigate the inheritance of 2,4-D resistance. The phenotypic screening of 15 F1s and RF1s each confirmed the homozygosity of the parental genotypes as all F1s and RF1s showed 2,4-D resistance equivalent to the resistant parent and also suggesting a dominant action of the putative resistant gene(s). Injury ratings were used to characterize 2,4-D resistance in the F2 population. The phenotypic classes suggested a monogenic inheritance (1:2:1) with co-dominant gene action. Twenty biotypes of prickly lettuce that have been identified as genetically distinct were planted in common gardens in 2010 and 2011 to quantify seed output. In field trials conducted in 2010, seed output of 20 different prickly lettuce biotypes varied from 0 to 53,000 seed per plant. Prickly lettuce seed germination in response to six different pH levels was quantified determine if prickly lettuce is better adapted to germinating at lower rather than higher soil pH. Germination varied by pH, with the greatest germination observed at a pH 4 (72%). Germination at ph 6 and pH 5 were similar, at 65% and 60%, respectively. Some germination was observed at pH 9 (0.1%), although the seedlings were deformed. No germination was observed at pH 7 or pH 8. Germination in DI water was 70%. It appears that prickly lettuce may be better adapted to germinate in relatively more acidic soils. A segregating population was created in 2012 by crossing two distinct eastern Washington biotypes [Parent 1 (P1) 6-9/13; Parent 2 (P2) 4-10/6]. Variation in the resulting population was considerable, and segregation was observed for phenotypic characteristics including leaf area, leaf perimeter, bolt number, and growth habit. The segregating F2 populations have been advanced to form a series of recombinant inbred lines for future work. Trials were conducted over two years and four locations to understand the effects of prickly lettuce control practices in CRP and their effects on fecundity in response to typical (low) inputs versus effective (high) inputs. Averaged over trials and years, applications of 2,4-D provided a 68% control of prickly lettuce and may be contributing to problems later in the season as plants in 2,4-D treated plots were more robust - 2,4-D is inexpensive and commonly used in CRP. In 2013, four studies were conducted to quantify yield loss in winter and spring wheat caused by prickly lettuce. Prickly lettuce failed to cause any measurable yield loss in winter wheat. Spring wheat is sensitive to prickly lettuce infestations. Density-dependent yield loss was not significant, but biomass-dependent yield loss was significant. For every gram increase in prickly lettuce biomass, yield decreased by 0.29 bushels. Moisture availability directly affects biomass production - in the spring in the PNW there is limited moisture, and thus limited biomass production potential. Prickly lettuce uses moisture, and limit the availability of moisture to the crop.
Publications
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2015
Citation:
Unger, R., I. C. Burke, and D. Huggins. 2011. Analyzing Seed Weed Bank Data using Random Forest Regression. Proc. West. Soc. Weed Sci. 64:154.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2015
Citation:
Unger, R., I. C. Burke, D. Huggins, M. Swanson, S. Higgins, and E. Gallandt. 2011. The effects of crop rotation and topography on the weed seed bank in the Palouse wheat region of Washington State. Soil Sci. Soc. Am. Abst. 612.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2015
Citation:
Raeder, A., I. Madsen, and I.C. Burke. Herbicide Cross-Resistance in Acetolactate-Synthase Inhibitor Resistant Prickly Lettuce. Proc. West. Soc. Weed Sci. 64:72.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2015
Citation:
Unger, R., M. E. Swanson, I. C. Burke, D. R. Huggins, E. R. Gallandt, and S. Higgins. 2012. The effects of crop rotation and terrain attributes on the weed seed bank. Proc. West. Soc. Weed Sci. 65:173.
- Type:
Journal Articles
Status:
Published
Year Published:
2015
Citation:
Bell, J. A., I. C. Burke, and T. Prather. 2011. Uptake, translocation and metabolism of aminocyclopyrachlor in prickly lettuce, yellow starthistle, and rush skeletonweed. Pest Manage. Sci.67:1338-1348.
- Type:
Journal Articles
Status:
Published
Year Published:
2015
Citation:
Riar, D. S., I. C. Burke, J. P. Yenish, and K. Gill. 2011. Physiological and genetic basis for 2,4-D resistance in prickly lettuce (Lactuca serriola). J. Agric. Food Chem. 59:9417-9423.
- Type:
Journal Articles
Status:
Published
Year Published:
2015
Citation:
Riar, D. S., S. Rustgi, I. C. Burke, K. S. Gill, and J. P. Yenish. 2011. EST-SSR development from 5 Lactuca species and their use in studying genetic diversity among L. serriola biotypes. J. Hered. 102:17-28.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2015
Citation:
Raeder, A. J., Burke, I. C. Economics and Efficacy of Clopyralid, Florasulam, Fluroxypyr, MCPA, Thifensulfuron-Methyl, Tribenuron and Bromoxynil plus Pyrasulfotole Broadleaf Weed Control Systems. 2014. Proc. West Soc. Weed Sci. 67:50.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2015
Citation:
Burke, I. C., J. L. Bell and M. Neff. 2013. QTL analysis of weedy prickly lettuce traits. Weed Sci. Soc. Am. 53:168.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2015
Citation:
Barco, M., A. J. Raeder, A. Attawan, J. L. Bell and I. C. Burke. ALS resistance in Prickly lettuce after 30 years of ALS inhibitor use. Weed Sci. Soc. Am. 53:102.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2015
Citation:
Bell, J. L., I. C. Burke, and M. M. Neff. 2012. Phenotypic and genetic comparison of distinct prickly lettuce biotypes. Weed Sci. Soc. Am. Abst. 52:285.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2015
Citation:
Burke, I. C., J. Bell, D. S. Riar, and S. Rustgi. 2012. Development and characterization of genomic resources for prickly lettuce. Plant and Animal Genome Conference. 20:W741.
|
Progress 10/01/13 to 09/30/14
Outputs
Target Audience: Outreach efforts targeted producers, Cooperative Extension personnel, and agricultural professionals who advise producers on weed management practices through in-person events (on-farm trials, field tours, winter meetings), and digital resources (annual reports of research, webpages). Changes/Problems: The only significant deviation that occurred in the course of this project was the result of the inability to track seed produced by prickly lettuce. As a consequence, it was not possible to attribute yield loss to prickly lettuce seed produced in conservation reserve program. What opportunities for training and professional development has the project provided? Multiple opportunities for training and professional development have been provided by the project. At the conclusion of the project, four graduate students will have received degrees working in part on prickly lettuce biology. Each student received significant training as part of the graduate education process that included courses and training to conduct research tailored to the individual needs of the student. Research associate and graduate student professional development emphasized communication of results at scientific and grower meetings. In addition to graduate students, two NSF funded REU students have engaged in research on prickly lettuce. The experience includes close mentoring in research methods, as well as how to communicate discoveries. How have the results been disseminated to communities of interest? Outputs from prickly lettuce research have been communicated at scientific meetings (primarily the Western Society of Weed Science and the Weed Science Society of America Annual Meetings) and at grower and commodity meetings. Popular press articles in widely distributed grower publications were also utilized to enhance awareness of prickly lettuce biology and management. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Prickly lettuce (Lactuca serriola L.) is an invasive weed with air-borne seeds that crosses boundaries at multiple scales - from field borders to regional boundaries. Prickly lettuce has become a widespread and troublesome weed in the PNW. It occurs in all rainfall zones and is difficult to control largely due to ALS resistance but also due to increased tolerance to 2,4-D and glyphosate. It infests conservation reserve program (CRP) land and appears to cause significant economic losses in wheat-based cropping systems, particularly in pulses. The objectives were: 1) Study the biology of prickly lettuce, focusing on weedy traits including herbicide resistance; 2) Determine prickly lettuce recruitment and seed rain in response to typical and effective CRP weed control inputs, 3) Determine prickly lettuce interference in winter and spring wheat. Work focused on understanding prickly lettuce biology with an emphasis on herbicide resistance and important weedy traits. Since the introduction of acetolactate synthase (ALS) inhibitor herbicides in the 1980's, the number of ALS-resistance weed species has increased rapidly, and ALS-resistant biotypes outnumber resistance to other herbicide modes of action. Twenty eastern Washington prickly lettuce biotypes from across the region were grown in a greenhouse and treated with multiple ALS-inhibiting herbicides. In conjunction with the greenhouse study, ALS mutations were studied by extracting DNA from the 20 biotypes and amplifying the nucleotide sequence containing domain A in each ALS gene. Known amino acid substitutions in the ALS gene of resistant biotypes were observed - the originally observed Pro197His substitution and a novel (to North America) Pro197Thr substitution. Cross resistance patterns to ALS-inhibiting herbicides confirmed the nucleotide substitutions. The results of this study confirm point mutations within the ALS gene of prickly lettuce in North America. In wheat fields near to Pullman, WA, several individual plants within a prickly lettuce population were observed to survive two separate broadcast applications of a glyphosate plus 2,4-D in mixture. Consequently, seed were collected from the surviving plants to determine the level of resistance to 2,4-D. The objectives of this study were to identify the response of putatively resistant prickly lettuce biotypes to increasing rates of 2,4-D and to investigate the mechanism of resistance. In dose response experiments, the GR50 for susceptible prickly lettuce was 8 and 9 times less than the field-collected biotype and its progeny, respectively. The resistant prickly lettuce biotype was found to be 27-fold more resistant to 2,4-D than the susceptible biotype based on regrowth of the resistant biotype. The resistant prickly lettuce biotype is cross-resistant to MCPA and dicamba, but not to aminopyralid, clopyralid, or fluroxypr. To determine the mechanism of resistance, absorption and translocation studies using 14C-2,4-D were conducted on the suspected 2,4-D resistant biotype and a known susceptible biotype. At 96 HAT, resistant and susceptible biotypes absorbed 33.8 and 42.7% of applied 14C-2,4-D, respectively, and out of the total herbicide absorbed, 74.5 and 70.1 % remained within the treated leaves of resistant and susceptible biotypes, respectively. At 96 HAT, the total amount of radioactivity translocated from the treated leaf to different plant parts was similar in both biotypes (25.5 and 29.9% for resistant and susceptible biotypes, respectively). However, 23% less 2,4-D was translocated to the crown of resistant biotype compared to susceptible biotype. Re-growth of resistant prickly lettuce biotypes commonly occurs from apical or lateral meristems located in the crown. Reduced herbicide translocation to the crown in resistant biotypes could be, in part, a mechanism for 2,4-D resistance in prickly lettuce. Crosses were completed to investigate the inheritance of 2,4-D resistance. The phenotypic screening of 15 F1s and RF1s each confirmed the homozygosity of the parental genotypes as all F1s and RF1s showed 2,4-D resistance equivalent to the resistant parent and also suggesting a dominant action of the putative resistant gene(s). Injury ratings were used to characterize 2,4-D resistance in the F2 population. The phenotypic classes suggested a monogenic inheritance (1:2:1) with co-dominant gene action. Twenty biotypes of prickly lettuce that have been identified as genetically distinct were planted in common gardens in 2010 and 2011 to quantify seed output. In field trials conducted in 2010, seed output of 20 different prickly lettuce biotypes varied from 0 to 53,000 seed per plant. Prickly lettuce seed germination in response to six different pH levels was quantified todetermine if prickly lettuce is better adapted to germinating at lower rather than higher soil pH. Germination varied by pH, with the greatest germination observed at a pH 4 (72%). Germination at ph 6 and pH 5 were similar, at 65% and 60%, respectively. Some germination was observed at pH 9 (0.1%), although the seedlings were deformed. No germination was observed at pH 7 or pH 8. Germination in DI water was 70%. It appears that prickly lettuce may be better adapted to germinate in relatively more acidic soils. A segregating population was created in 2012 by crossing two distinct eastern Washington biotypes [Parent 1 (P1) 6-9/13; Parent 2 (P2) 4-10/6]. Variation in the resulting population was considerable, and segregation was observed for phenotypic characteristics including leaf area, leaf perimeter, bolt number, and growth habit. The segregating F2 populations have been advanced to form a series of recombinant inbred lines for future work. Trials were conducted over two years and four locations to understand the effects of prickly lettuce control practices in CRP and their effects on fecundity in response to typical (low) inputs versus effective (high) inputs. Averaged over trials and years, applications of 2,4-D provided a 68% control of prickly lettuce and may be contributing to problems later in the season as plants in 2,4-D treated plots were more robust - 2,4-D is inexpensive and commonly used in CRP. In 2013, four studies were conducted to quantify yield loss in winter and spring wheat caused by prickly lettuce. Prickly lettuce failed to cause any measurable yield loss in winter wheat. Springwheat is sensitive to prickly lettuce infestations. Density-dependent yield loss was not significant, but biomass-dependent yield loss was significant. For every 10g/square meterincrease in prickly lettuce biomass, yield decreased by 0.29 bushels/acre. Moisture availability directly affects biomass production - in the spring in the PNW there is limited moisture, and thus limited biomass production potential. Prickly lettuce uses moisture, and limit the availability of moisture to the crop.
Publications
- Type:
Journal Articles
Status:
Accepted
Year Published:
2014
Citation:
Bell, J. A. and I. C. Burke. 2014. Rubber content and quality of eastern Washington prickly lettuce biotypes. J. Agric. Food Chem. (Accepted).
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2013
Citation:
Burke, I. C., J. L. Bell and M. Neff. 2013. QTL analysis of weedy prickly lettuce traits. Weed Sci. Soc. Am. 53:168.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2013
Citation:
Bell, J. L., I. C. Burke, and M. Neff. 2013. Quantitative trait loci associated with rubber production in prickly lettuce (Lactuca serriola L.). Plant and Animal Genome 21:P0701.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2014
Citation:
Barco, M., A. J. Raeder, A. Attawan, J. L. Bell and I. C. Burke. ALS resistance in Prickly lettuce after 30 years of ALS inhibitor use. Weed Sci. Soc. Am. 53:102.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2012
Citation:
Bell, J. L., I. C. Burke, and M. M. Neff. 2012. Phenotypic and genetic comparison of distinct prickly lettuce biotypes. Weed Sci. Soc. Am. Abst. 52:285.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2012
Citation:
Burke, I. C., J. Bell, D. S. Riar, and S. Rustgi. 2012. Development and characterization of genomic resources for prickly lettuce. Plant and Animal Genome Conference. 20:W741.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2012
Citation:
Manuchehri, M. R., E. P. Fuerst, and I. C. Burke. 2012. Effects of planting density and weed pressure on grain quality in eastern Washington. Proc. West. Soc. Weed Sci. 65:46.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2014
Citation:
Raeder, A., I. Madsen, and I.C. Burke. Herbicide Cross-Resistance in Acetolactate-Synthase Inhibitor Resistant Prickly Lettuce. Proc. West. Soc. Weed Sci. 64:72.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2010
Citation:
Bell, J., I. C. Burke, and M. Neff. 2010. Characterization of rubber production in eastern Washington prickly lettuce biotypes. Proc. West. Soc. Weed Sci. 63:91.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2010
Citation:
: Riar, D. S., I. C. Burke, J. Bell, K. Gill, and J. P. Yenish. 2010. Inheritance and Metabolism of 2,4-D Resistance in Prickly Lettuce. Proc. West. Soc. Weed Sci. 63:39.
- Type:
Theses/Dissertations
Status:
Published
Year Published:
2014
Citation:
Bell, Jared. May 2013. Latex and Rubber Quality and Quantity in Prickly Lettuce. Washington State University Molecular Plant Sciences Program.
- Type:
Theses/Dissertations
Status:
Published
Year Published:
2012
Citation:
Manuchehri, Misha. December 2012. Relative Competitiveness of Spring Crops for Dryland Organic Systems. Department of Crop and Soil Sciences.
- Type:
Theses/Dissertations
Status:
Published
Year Published:
2010
Citation:
Jamin Smitchger, M.S. July 2010. Critical Period of Weed Control in Chickpea and Lentil.
- Type:
Theses/Dissertations
Status:
Published
Year Published:
2010
Citation:
Dilpreet Singh Riar, 2010, Development of molecular markers for detection of 2,4-D resistance in prickly lettuce.
|
Progress 01/01/13 to 09/30/13
Outputs
Target Audience: Farm Services and Natural Resource Conservation Service personnel; growers and land owners; regional and commodity specific extension specialists; weed scientists; and agroecosystem managers. Changes/Problems: Two significant deviations have occurred. The timeline to have a prickly lettuce biotype useful for testing seed movement has been delayed due to lack of sufficient seed. The most significant problem centers on the ability to establish prickly lettuce in the field for yield loss trials. Two different methods have been evaluated - transplanting and seeding. Both have failed, and this year we will focus on identifying an alternative method to evaluating prickly lettuce competition. What opportunities for training and professional development has the project provided? The project is conceptually challenging, as the techniques are not typical for weed scientists or program staff and students. Staff and students have had to learn new skills that are more typical for plant breeding programs. How have the results been disseminated to communities of interest? Results have been disseminated largely through interaction with appropriate personnel, and through presentations to grower groups. What do you plan to do during the next reporting period to accomplish the goals? Troubleshooting prickly lettuce field establishment for yield loss trials is the primary emphasis during the next reporting period.
Impacts
What was accomplished under these goals?
Prickly lettuce is an invasive weed with air-borne seeds that crosses boundaries at multiple scales - from field borders to regional boundaries. It infests CRP land and appears to cause significant economic losses in wheat-based cropping systems. The research objectives will allow for the analysis of linkages between CRP management and consequent infestation and economic loss in adjacent cropland. The objectives are: 1) Determine prickly lettuce recruitment and seed rain in response to typical and effective CRP weed control inputs, 2) Determine prickly lettuce seed dispersal in order to predict seed movement from CRP onto adjacent crop production land, and 3) Determine fall and spring emerging prickly lettuce interference and seed rain dynamics in winter and spring wheat. Work in 2013 continued that of 2012, and focused on developing a working prickly lettuce population that could be easily field-identified for seed deposition experiments and would be resistant to deer grazing in order to address Objective 2. Selection continued on the population created in 2012 by crossing two distinct eastern Washington biotypes [Parent 1 (P1) 6-9/13; Parent 2 (P2) 4-10/6]. Phenotypic characteristics used included leaf area, leaf perimeter, bolt number, and growth habit. An F2 selection was made in 2012, and increased in 2013, as insufficient seed were generated for use in field experiments in 2013. In 2013, four studies were conducted to address objective 3 and quantify yield loss in winter and spring wheat caused by prickly lettuce. The first trial was in winter wheat, conducted at two sites, while the second trial was in spring wheat, also conducted at two sites. Trial treatments included three wheat planting rates, and three prickly lettuce seeding rates, arranged in a randomized complete block design with 4 replications. Prickly lettuce failed to cause any measurable yield loss in winter wheat, confirming previous trials. Prickly lettuce failed to establish in the spring wheat trials, largely due to insufficient moisture, and will be repeated in 2014. Outputs of basic research projects are disseminated at scientific meetings, while outputs of applied biological and field efficacy studies are also extended to growers.
Publications
|
Progress 01/01/12 to 12/31/12
Outputs
OUTPUTS: Prickly lettuce is an invasive weed with air-borne seeds that crosses boundaries at multiple scales - from field borders to regional boundaries. It infests Conservation Reserve Program (CRP) land and appears to cause significant economic losses in wheat-based cropping systems. The research proposed in this project has the potential to greatly improve our understanding of the biology of this species and the implications of management inputs in different adjacent managed ecosystems. The research objectives will allow for the analysis of linkages between CRP management and consequent infestation and economic loss in adjacent cropland. The objectives are: 1) Determine prickly lettuce recruitment and seed rain in response to typical and effective CRP weed control inputs, 2) Determine prickly lettuce seed dispersal to predict seed movement from CRP onto adjacent crop production land, and 3) Determine fall and spring emerging prickly lettuce interference and seed rain dynamics in winter and spring wheat.<p> Work in 2012 focused in developing a working population that could be easily field-identified for seed deposition experiments and would be resistant to deer grazing to address Objective 2. Two distinct eastern Washington biotypes [Parent 1 (P1) 6-9/13; Parent 2 (P2) 4-10/6] were crossed to generate an F2 segregating population. Phenotypic characteristics including leaf area, leaf perimeter, bolt number, and growth habit were collected. To examine phenotype leaf differences, four fully expanded leaves from each plant were collected and scanned on a flatbed scanner. Leaf area and perimeter were calculated using ImageJ. Leaf area and perimeter had a normal distribution indicating multiple interacting genes control these traits. Deer grazing activity was recorded. The number of bolts was counted on each plant to reveal a normal distribution suggesting bolt number is a quantitative trait. Growth habit varied between parents with P1 having a more erect bolting pattern with a single dominate bolt and P2 a prostrate bolt growth pattern. Growth habit was scored 1-5, 1 resembling P1 and 5, P2. Growth habit also had a normal distribution over the population, while deer grazing was a dominant trait. An F2 selection was made and increased for use in field experiments addressing Objective 2 in 2013 that has an easily identifiable phenotype, is resistant to deer grazing, and is sensitive to ALS-inhibiting herbicides.<p> Outputs of basic research projects are disseminated at scientific meetings, while outputs of applied biological and field efficacy studies are also extended to growers. PARTICIPANTS: Arron Carter, Kim Campbell, Michael Neff TARGET AUDIENCES: Growers, NRCS CRP Policy Makers, Farm Services PROJECT MODIFICATIONS: Modification of the proposal was required to ensure that prickly lettuce seed released into the environment was not herbicide resistant. The process is described in outputs. The modification caused a revision in the timeline.
Impacts
To test the central hypothesis that weed control practices in CRP are having an effect in adjacent cropland and to address objective 1, trials were conducted over two years and four locations to understand the effects of prickly lettuce control practices in CRP and their effects on fecundity in response to typical (low) inputs versus effective (high) inputs. Typical and effective inputs have been identified: The highest level of control was provided when flumioxazin mixed with aminopyralid + 2,4-D. In contrast a traditional application of 2,4-D provided a 68% control of prickly lettuce and may be contributing to problems later in the season as plants in 2,4-D treated plots were more robust.<p> To address objective 2, 20 biotypes of prickly lettuce that have been identified as genetically distinct were planted in common gardens in 2010 and 2011 to quantify seed output. Prickly lettuce seed output is biotype (and genotype) dependent based on common garden experiments. In field trials conducted in 2010, seed output of 20 different prickly lettuce biotypes varied from 0 to 53,000 seed per plant. There also appears to be strong preferential grazing of certain biotypes by deer.<p> Two studies were conducted to address objective 3 and quantify yield loss in winter and spring wheat caused by prickly lettuce. The first trial was in winter wheat, while the second trial was in spring wheat. Prickly lettuce failed to cause any measurable yield loss in winter wheat while spring wheat is sensitive to prickly lettuce infestations. Density-dependent yield loss was not significant. Biomass-dependent yield loss was significant. For every gram increase in prickly lettuce biomass, yield loss increased 0.29 bushels. Findings from this project have been extended to target audiences, but there has been no formal evaluation of a change in actions or conditions.
Publications
- No publications reported this period
|
Progress 01/01/11 to 12/31/11
Outputs
OUTPUTS: The objectives of this Hatch project are: 1) Determine prickly lettuce recruitment and seed rain in response to typical and effective CRP weed control inputs, 2) Determine prickly lettuce seed dispersal to predict seed movement from CRP onto adjacent crop production land, and 3) Determine fall and spring emerging prickly lettuce interference and seed rain dynamics in winter and spring wheat. To test the central hypothesis that weed control practices in CRP are having an effect in adjacent cropland and to address objective 1, trials were conducted over two years and four locations to understand the effects of prickly lettuce control practices in CRP and their effects on fecundity in response to typical (low) inputs versus effective (high) inputs. Field trials were established on two different conservation reserve program (CRP) sites in the Palouse region of Eastern Washington: Dusty and Palouse. Control of prickly lettuce was evaluated at each site as well as the efficacy of combinations of herbicides with soil residual activity and herbicides with postemergence activity. Prickly lettuce cover was evaluated using a point-intercept method across the diagonal of each plot at intervals of 14, 32, 71, and 106 DAT. Percent weed free was calculated from percent cover of prickly lettuce in each plot. Averaged over trials and years, applications of 2,4-D provided 68% control of prickly lettuce and may be contributing to problems later in the season as plants in 2,4-D treated plots were more robust. To address objective 2, 20 biotypes of prickly lettuce that have been identified as genetically distinct (Riar et al., 2011) were planted in common gardens in 2010 and 2011 to quantify seed output. Prickly lettuce seed output is biotype (and genotype) dependent based on common garden experiments. In field trials conducted in 2010, seed output of 20 different prickly lettuce biotypes varied from 0 to 53,000 seed per plant. There also appears to be strong preferential grazing of certain biotypes by deer. Two studies were conducted to address objective 3 and quantify yield loss in winter and spring wheat caused by prickly lettuce. Prickly lettuce failed to cause any measurable yield loss in winter wheat. Spring wheat is sensitive to prickly lettuce infestations. Density-dependent yield loss was not significant. Biomass-dependent yield loss was significant. For every 10Kg increase in prickly lettuce biomass, spring wheat yield decreased by 19.5 Kg on a hectare basis. PARTICIPANTS: Stephen Reinertsen and Bruce Palmer, The McGregor Company. Additional research collaborators: Michael Neff, WSU-CSS; Kulvinder Gill, WSU-CSS. Students: Dilpreet Riar, WSU Ph.D. Student; Jared Bell, WSU Ph.D. Student. TARGET AUDIENCES: Growers, state and federal agency personnel, agriculture industry, and other extension and research personnel are the main target audiences for this work. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
No impacts to report at this time.
Publications
- Riar, D.S., S.Rustgi, I.Burke, K.Gill, and J.Yenish. 2011. EST-SSR development from five Lactuca species and their use in studying genetic diversity among L. serriola biotypes. Journal of Heredity 102:17-28.
- Bell, J., I.Burke, and T.Prather. 2011. Physiological behavior of the ester and acid of aminocyclopyrachlor in prickly lettuce, yellow starthistle, and rush skeletonweed. Pest Management Science. 67:1338-1348.
- Smitchger, J., I.Burke, and J.Yenish. 2011. The critical period of weed control in chickpea. Weed Science. DOI 10.1614/WS-D-11-00069.1.
- Riar, D.S., J.Yenish, D.Ball, and I.Burke. 2011. Efficacy of postemergence herbicides with a reduced herbicide applicator in fallow. Weed Technology: A Journal of the Weed Science Society of America. 25:447-453.
- Riar, D.S., I.Burke, J.Yenish, and K.Gill. 2011. Physiological and genetic basis for 2,4-D resistance in prickly lettuce (Lactuca serriola). Journal of Agricultural and Food Chemistry. 59:9417-9423
|
Progress 01/01/10 to 12/31/10
Outputs
OUTPUTS: Prickly lettuce produces copious quantities of highly viable, wind-dispersed seed. Failure to control prickly lettuce in CRP land adjacent to wheat fields could lead to greater problems in adjacent wheat fields. Therefore, field trials were established on two different conservation reserve program (CRP) sites in the Palouse region of Eastern Washington, Dusty and Palouse. Control of prickly lettuce was evaluated at each site as well as the efficacy of combinations of herbicides with soil residual activity and herbicides with post emergence activity. The study was an RCBD design with a factorial arrangement of treatments. The study had three factors: 1) flumioxazin (0.25 lb ai/a), imazapic (0.05 lb ai/a), or nothing; 2) 2,4-D (0.5 lb ai/a), aminopyralid (0.109 lb ai/a), aminopyralid + 2,4-D, triclopyr (1 lb ai/a), triclopyr + 2,4-D, clopyralid (0.375 lb ai/a), clopyralid + 2,4-D, or nothing; and 3) mowing or no mowing. No surfactants were included to minimize injury to desired grass species. Prickly lettuce cover was evaluated using a point-intercept method across the diagonal of each plot at intervals of 14, 32, 71, and 106 DAT. Percent weed free was calculated from percent cover of prickly lettuce in each plot. Prickly lettuce control at the two sites was similar 32 days after treatment (DAT). At the Dusty site all treatments provided >94% control of prickly lettuce with no differences among treatments when evaluated at 106 DAT. This was most likely due to a lack of mid- and late-season precipitation, which reduced prickly lettuce density considerably. At the Palouse site 2,4-D, aminopyralid, clopyralid, or triclopyr applied alone had the least control (<68% control). When applied in combination with flumioxazin control was 70% to 100%. The highest level of control was provided when flumioxazin was mixed with aminopyralid + 2,4-D. Varied results from the use of imazapic were observed, from 51% to 92% control, depending on tank mix partners. In contrast, a traditional application of 2,4-D provided 68% control of prickly lettuce and may be contributing to problems later in the season as plants in 2,4-D treated plots were more robust. Prickly lettuce control was 87% at the Palouse site with mowing only - a timely mowing can reduce prickly lettuce seed production. PARTICIPANTS: M. M. Neff, K. Gill, S. Rustgi, J. Bell TARGET AUDIENCES: Farmers, state and federal agency personnel, agriculture industry, and other extension and research personnel are the main target audiences for this work. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Results of the CRP efficacy studies have been presented at the Western Society of Weed Science and regional grower meetings, likely resulting in some consideration by growers when choosing a herbicide for CRP maintenance.
Publications
- Riar, D.S., S.Rustgi, I.Burke, K.Gill, and J.Yenish. 2010. EST-SSR development from five Lactuca species and their use in studying genetic diversity among L. serriola biotypes.. Journal of Heredity .
|
|