Progress 10/01/13 to 09/30/14
Outputs
Target Audience: Sugarcane and vegetable growers, extension agents. The results were presented at professional meetings and in scientific publications for the scientific community. Seminars were held to provide information to growers and extension agents. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? Objective 1). The results of the atrazine and metribuzin dissipation study were disseminated to growers and extension agents at a sugarcane focus group meeting in Florida. Also, results of the study were disseminated to the wider scientific community via publication in the Weed Technology journal. Objective 2). The results of the study that confirmed, characterized, and provided management options for glyphosate-resistant ragweed parthenium in South Florida were presented at state and regional scientific meetings. The results were also presented at a grower meeting in Florida. Objective 3). The study on weed management options for energycane on mineral soils in south Florida are to be published as an extension article to provide growers and county extension agents with herbicides that can be used to manage weeds in this crop if planted hectares increase in the future. How have the results been disseminated to communities of interest? The results have been disseminated through presentations at grower and scientific meetings. The results have also been published in peer reviewed scientific journals. What do you plan to do during the next reporting period to accomplish the goals? A final report will be prepared.
Impacts
What was accomplished under these goals?
Objective 1). Study resultsshowed that enhanced atrazine degradation occurs on organic soils under field conditions in the EAA compared to metribuzin. This results in shorter residual atrazine activity. Based on thestudy, metribuzin is a better option for weed control in sugarcane grown on organic soils of the EAA exhibiting enhanced atrazine degradation. This research was published in the Weed Technology Journal. Objective 2). Studies were conducted to evaluate the potential phytotoxic effect of ragweed parthenium residue on emergence and early growth of sugarcane on organic and minerals soils of Florida. Ragweed parthenium is commonly associated with noncrop areas in the EAA. Results of the study showed that on mineral soil, sugarcane emergence and growthdecreased <5% in response to ragweed parthenium residue at the current infestation level in Florida. In contrast, residue of ragweed parthenium had no effect on sugarcane emergence and growth on organic soil. The results showed that there is no potential adverse effect of ragweed parthenium residue on sugarcane grown on mineral and organic soils in Florida at the current infestation level. Objective 3). Energycane has been proposed as a potential perennial bioenergy crop for lignocellulosic-derived fuel production in the United States. No herbicides are currently labeled for use in energycane. However, herbicides used in commercial sugarcane and other crops can potentially be used if there is acceptable crop tolerance. Studies were conducted to evaluate the tolerance of energycane to preemergence and postemergence herbicides commonly used in conventional sugarcane and other crops. Results showed that preemergence application of atrazine, metribuzin, S-metolachlor, mesotrione, pendimethalin, and diuron at rates labeled for sugarcane were not phytotoxic to energycane. Postemergence application of atrazine, ametryn, mesotrione, carfentrazone, 2,4-D amine, dicamba, halosulfuron, asulam, metribuzin, and trifloxysulfurondid not cause any phytotoxicityat labeled use rate for sugarcane. The results indicated that several herbicides used for weed management in sugarcane may potentially be used in energycane for weed control if planted hectares increase in the future.
Publications
- Type:
Journal Articles
Status:
Accepted
Year Published:
2014
Citation:
Fernandez, J. V. g, D. C. Odero, G. E. MacDonald, J. Ferrell, and Lyn A. Gettys. Confirmation, characterization and management of glyphosate-resistant ragweed parthenium (Parthenium hysterophorus L.) in the Everglades Agricultural Area of south Florida. Weed Technology (Accepted).
- Type:
Journal Articles
Status:
Published
Year Published:
2014
Citation:
Odero, D. C. and D. L. Shaner. 2014. Field dissipation of atrazine and metribuzin in organic soils in Florida. Weed Technology 28:578-586.
- Type:
Journal Articles
Status:
Under Review
Year Published:
2014
Citation:
Fernandez,J. V., D. C. Odero?, and A. L. Wright Effects of Parthenium hysterophorus L. residue on early sugarcane growth in organic and mineral soils. Crop Protection (Under Review).
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Progress 01/01/13 to 09/30/13
Outputs
Target Audience: The target audiences for this period have been growers (sugarcane, vegetables), extension agents, agricultural industry, and other agricultural stakeholders in the Everglades Agricultural Area. All these audiences will benefit from this report by gaining new knowledge on economical weed management practices for the different cropping systems in the Everglades Agricultural Area. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? OUTPUTS: Objective 1) Field trials were conducted in the Evergaldes Agricultural Area to evaluate dissipation of atrazine and metribuzin. Soil samples were taken at 0 to 56 days after treatment (DAT) prior to freezing at -4 F until analysis. Herbicides were extracted samples were taken at 0 to 56 days after treatment (DAT) prior to freezing at -4 F until analysis. Herbicides were extracted from the soil using toluene and water extraction procedures. Data were presented at the American Society of Sugar Cane Technologists Florida and Louisiana Divisions Joint Annual Meeting. Objective 2) Field and greenhouse studies were carried out to determine whether ragweed parthenium in the Everglades Agricultural Area has evolved resistance to glyphosate and determine management options for this population using several postemergence herbicides. Results of this project were presented at the Southern Weed Science Society and Florida Weed Science Society annual meetings. Objective 3) Influence of phosphorus (P) on the critical period of weed control (CPWC) in lettuce was evaluated at UF-EREC. Phosphorus was added at different levels and for each P level, both increasing duration of weed interference and weed-free period were imposed at 0 to 8 weeks after emergence. Marketable fresh lettuce yield was harvested at the end of the growing season to determine the CPWC. Phosphorus forms and availability in the Evergaldes Agricultural Area vegetable soils under variably timed weed control, and weed control timing effects on soil and plant tissue nutrient dynamics for the Evergaldes Agricultural Area lettuce production were evaluated. The CPWC in snap beans was evaluated in a manner similar to the lettuce study. Results were presented at the Southern Weed Science Society and Weed Science Society of America annual meetings. Objective 4) Labeled sugarcane herbicides asulam and trifloxysulfuron were evaluated for management of giant reed. The herbicides were applied at up to twice the label use rate in sugarcane. Above ground biomass was harvested at 21 DAT for the greenhouse study. Presence of respouts of giant reed was recorded at 14 days after above ground biomass harvesting. For the field study, a visual estimation of control was evaluated at 14 DAT and above ground biomass harvested at 42 DAT. Data presented at the Florida Weed Science Society Meeting and at the UF-EREC (seminar). PARTICIPANTS: Dr. Dennis Odero, PI; Jose Fernandez, M.S. Student, University of Florida – conducted studies on determining resistance of ragweed parthenium to glyphosate and available management options; Dr. Greg MacDonald – supervised Jose Fernandez’s project on absorption and translocation studies to determine mechanisms of resistance of ragweed parthenium to glyphosate; Dr. Dale Shaner, USDA-ARS Fort Collins, conducted soil analysis for dissipation study; Dr. Alan Wright - conducted soil and tissue analysis for the phosphorus lettuce study. Sugarcane Grower Cooperative of Florida provided experimental sites for dissipation and ragweed parthenium studies.TARGET AUDIENCES: Sugarcane and vegetable growers, extension agents, and the scientific community. Results presented at professional meetings and in scientific publications for the scientific community. Seminars held to provide information to growers and extension agents. How have the results been disseminated to communities of interest? Results have been disseminated at grower field days and meetings, and professional meetings. Also, these results will be published in the University of Florida Electronic Data Information Source which is a collection of information on topics including profitable and sustainable agricultural production. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
A study on field dissipation of triazine herbicides on organic soils of the Everglades Agricultural Area showed that the bioavailable fraction of atrazine dissipated more rapidly than the total amount of atrazine in the soil. Half-lives of the total and bioavailable fraction of atrazine in organic soil ranged between 3.9 to 12.1 days and 1.0 to 7.5 days, respectively. Atrazine dissipated more rapidly than metribuzin, and metribuzin was more bioavailable than atrazine. Similarly, dissipation of the bioavailable fraction of metribuzin was more rapid than the total amount of metribuzin in the soil. Half-lives of the total and bioavailable fraction of metribuzin in organic soil ranged between 16.2 to 24.8 days and 6.0 to 14.3 days, respectively. Results of this study show that enhanced atrazine degradation occurs on organic soils under field conditions in the Everglades Agricultural Area resulting in shorter residual activity of atrazine. These results illustrate that metribuzin is a viable alternative for weed control for sugarcane growers in organic soils in the Everglades Agricultural Area exhibiting rapid degradation of atrazine and concomitant loss of residual weed control. Approximately 50,000 ha of the sugarcane are now treated with metribuzin in the Everglades Agricultural Area. Ragweed parthenium is commonly found along field edges, canals, ditch banks, and noncrop areas in the Everglades Agricultural Area. Research results from this project determined that ragweed parthenium in the Everglades Agricultural Area has evolved glyphosate resistance following repeated use of glyphosate for weed control in noncrop areas and fallow fields. Herbicides including aminocyclopyrachlor plus chlorsulfuron, aminopyralid, saflufenacil, saflufenacil + dimethenamid-P, and hexazinone were shown to provide complete control of ragweed parthenium in the Everglades Agricultural Area. Based on these results, growers now have herbicide options for control of glyphosate resistant ragweed parthenium in the Everglades Agricultural Area and stop its encroachment into cultivated fields. The beginning of the critical period of weed control in lettuce, an important leafy green vegetable was delayed at the highest phosphorus level while the end was hastened at the same level in field studies conducted in the Everglades Agricultural Area. This shows that inadequate levels of phosphorus fertilization in lettuce will result in the need for more intensive weed management practices to achieve acceptable yields in the Everglades Agricultural Area. Research also showed that saflufenacil plus dimethenamid-P and pyroxasulfone can be used to provide efficacious weed control in sweet corn, a major winter crop in the Everglades Agricultural Area. Asulam and trifloxysulfuron applied at double the sugarcane label use rate were ineffective on controlling giant reed, a potential bioenergy crop. Double use rates of these herbicides would not be within the label use rate and would be phytotoxic to sugarcane. These results show that containment of aggressively spreading giant reed in sugarcane if introduced as an energy crop in the Everglades Agricultural Area would not be possible with the currently available herbicide control options for growers.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2014
Citation:
Fernandez, J. V.*, D. C. Odero, G. E. MacDonald, and J. Ferrell. 2014. Parthenium hysterophorus L. control in response to pyraflufen-ethyl application. Crop Protection 57:35-37.
- Type:
Journal Articles
Status:
Published
Year Published:
2013
Citation:
Odero, D. C. and A. L. Wright. 2013. Phosphorus application influences the critical period of weed control in lettuce. Weed Science 61:410-414.
- Type:
Journal Articles
Status:
Published
Year Published:
2013
Citation:
Odero, D. C. and A. L. Wright. 2013. Comparison of pyroxasulfone, s-metolachlor, and mesotrione for weed control in sweet corn on organic soils. Crop Management Online. doi:10.1094/CM-2013-0227-01-RS.
- Type:
Journal Articles
Status:
Published
Year Published:
2013
Citation:
Odero, D. C. and A. L. Wright. 2013. Response of sweet corn to pyroxasulfone in high organic matter soils. Weed Technology 27:341-346.
- Type:
Journal Articles
Status:
Accepted
Year Published:
2013
Citation:
Odero, D. C., A. L. Wright, and J. V. Fernandez*. Sweet corn response and weed control to saflufenacil plus dimethenamid-P in organic soils. Weed Technology. doi: http://dx.doi.org/10.1614/WT-D-13-00097.1.
- Type:
Theses/Dissertations
Status:
Published
Year Published:
2013
Citation:
Fernandez, J. V.2013. Description of glyphosate resistance and management of ragweed parthenium (Parthenium hysterophorus L.) in the Everglades Agricultural Area. MS Thesis, University of Florida.
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Progress 01/01/12 to 12/31/12
Outputs
OUTPUTS: Objective 1) Field trials were conducted in the EAA to evaluate dissipation of atrazine and metribuzin. Soil samples were taken at 0 to 56 days after treatment (DAT) prior to freezing at -4 F until analysis. Herbicides were extracted from the soil using toluene and water extraction procedures. Data were presented at the American Society of Sugar Cane Technologists Florida and Louisiana Divisions Joint Annual Meeting. Objective 2) Field and greenhouse studies were carried out to evaluate the response of ragweed parthenium to several postemergence herbicides. Herbicides were applied to bolting and rosette ragweed parthenium for the field and greenhouse studies, respectively. Visual estimation of control was evaluated up to 60 DAT for the field study. For the greenhouse study, visual evaluation of control and harvesting of above ground biomass was done at 14 DAT. Seminar on ragweed parthenium control options was presented at the University of Florida Tropical Research and Education Center. Objective 3) Influence of phosphorus (P) on the critical period of weed control (CPWC) in lettuce was evaluated at UF-EREC. Phosphorus was added at different levels and for each P level, both increasing duration of weed interference and weed-free period were imposed at 0 to 8 weeks after emergence. Marketable fresh lettuce yield was harvested at the end of the growing season to determine the CPWC. Phosphorus forms and availability in the EAA vegetable soils under variably timed weed control, and weed control timing effects on soil and plant tissue nutrient dynamics for the EAA lettuce production were evaluated. The CPWC in snap beans was evaluated in a manner similar to the lettuce study. Objective 4) Labeled sugarcane herbicides asulam and trifloxysulfuron were evaluated for management of giant reed. The herbicides were applied at up to twice the label use rate in sugarcane. Above ground biomass was harvested at 21 DAT for the greenhouse study. Presence of respouts of giant reed were recorded at 14 days after above ground biomass harvesting. For the field study, a visual estimation of control was evaluated at 14 DAT and above ground biomass harvested at 42 DAT. Data presented at the Florida Weed Science Society Meeting and at the UF-EREC (seminar). PARTICIPANTS: Dr. Dennis Odero, PI; Jose Fernandez, M.S. Student, University of Florida; Dr. Dale Shaner, USDA-ARS Fort Collins, conducted soil analysis for dissipation study; Dr. Alan Wright - conducted soil and tissue analysis for the phosphorus lettuce study. Sugarcane Grower Cooperative of Florida provided experimental sites for dissipation and ragweed parthenium studies. TARGET AUDIENCES: Sugarcane and vegetable growers, extension agents, and the scientific community. Results presented at professional meetings and in scientific publications for the scientific community. Seminars held to provide information to growers and extension agents. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Triazine herbicides (atrazine and metribuzin) are extensively used to provide residual weed control in sugarcane. Results of the dissipation study showed that atrazine dissipated more rapidly than metribuzin, and metribuzin was more bioavailable than atrazine. These results illustrate that metribuzin is a viable alternative for weed control for sugarcane growers in organic soils in the EAA exhibiting rapid degradation of atrazine and concomitant loss of residual weed control. Approximately 50,000 ha of the sugarcane are now treated with metribuzin in the EAA. Saflufenacil was found to provide total burndown of ragweed parthenium with no response to glyphosate in the EAA. It provided the same level of control for both rosette and bolting ragweed parthenium. Based on these results, growers now have a herbicide option for control of ragweed parthenium with no response to glyphosate in the EAA. The beginning of the critical period of weed control in lettuce was delayed at the highest phosphorus level while the end was hastened at the same level. This shows that inadequate levels of phosphorus fertilization in lettuce will result in the need for more intensive weed management practices to achieve acceptable yields in the EAA. Asulam and trifloxysulfuron applied at double the sugarcane label use rate were ineffective on controlling giant reed. Double use rates of these herbicides would not be within the label use rate and would be phytotoxic to sugarcane. These results show that containment of aggressively spreading giant reed in sugarcane if introduced as an energy crop in the EAA would not be possible with the currently available herbicide control options for growers.
Publications
- Odero, D. C. and Shaner, D. L. 2012. Dissipation of atrazine and metribuzin in high organic matter soils. Proceedings of Southern Weed Science Society 65:40.
- Odero, D. C. and Gilbert, R. A. 2012. Response of giant reed (Arundo donax) to asulam and trifloxysulfuron. Weed Technology 26:71-76.
- Odero, D. C. 2012. Response of ragweed parthenium (Parthenium hysterophorus) to saflufenacil and glyphosate. Weed Technology 26:443-448.
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