THE PHYSIOLOGY AND BIOCHEMISTRY OF HERBICIDE ACTION, SELECTIVITY, AND DEGRADATION.

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 1008673
• Project Start Date: Feb 1, 2016
• Project End Date: Aug 31, 2020
• Program Code: [(N/A)]- (N/A)

Project Director
Penner, D.

Recipient Organization
MICHIGAN STATE UNIV
(N/A)
EAST LANSING,MI 48824

Performing Department
Plant, Soil and Microbial Science

Non Technical Summary
Herbicides constitute 80 or more percent of the total pesticide sales in the USA. Without them, the United States would have difficulty feeding itself and certainly would not be an agricultural exporting nation. Agricultural exports are the backbone of US exports and their losses would lead to catastrophic economic consequences. For the US to remain competitive in agricultural production, there will need to be increased efficiency in crop production. With respect to herbicides, this means more bushels per acre per dollar spent on herbicides. Societal concerns are that this be accomplished with decreased risk to the environment. Current concerns focus on the lack of acceptance of genetically modified crops. The use of a single herbicide for weed control on a given field for several years has resulted in the appearance of problematic weeds resistant to the herbicide that has been used. Although the use of a combination of herbicides for the control of these weeds may be optimal to ultimately achieve a reduction of herbicide-resistant weed seed in the seed banks in the soil (Beckie and Reboud, 2009), herbicide interactions may occur giving unexpected results. A greater understanding of the physiology and biochemistry of herbicide action, selectivity and degradation is necessary to achieve the desired increased productivity and the decreased risk to the environment. This understanding may facilitate more effective and judicious use of existing herbicides and greater insight in the discovery and quest for new herbicides, especially of biological origin, to solve both existing and new weed control problems. It may also facilitate the development of more effective adjuvants to maximize the utility of existing herbicides.

Animal Health Component

50%

Research Effort Categories

Basic

50%

Applied

50%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
213	1820	1140	100%

Knowledge Area
213 - Weeds Affecting Plants;

Subject Of Investigation
1820 - Soybean;

Field Of Science
1140 - Weed science;

Keywords

herbicides

glyphosate

herbicide action, selectivity, and degradation

dew

volatility

nano tehcnology

Goals / Objectives
The objectives of this project are as follows:a) Formulate and reformulate herbicide adjuvants for use with growth regulator herbicides with the goal of reducing their volatility and off-target movement.b) Prevent loss of postemergence herbicide activity when the herbicides are applied at a time when there is dew on the leaves by the formulation of adjuvants that prevent loss and determine the basis for the protection.c) Use of nanotechnology to formulate novel adjuvants to enhance compatibility with herbicides and other adjuvants.

Project Methods
Adjuvant formulations and compatibility testing will be done in the laboratory. Secondly, 14C-herbicide formulation with adjuvants and evaluation of the basis of the adjuvant action will be done in the laboratory.a) Evaluation of growth regulator herbicide vapor movement will be done in small chambers resembling angel food cake pans with plants in one and another tipped upside down on top of it in the greenhouse. Wheat plants on bare soil receive the herbicide and after the herbicide is dry sensitive plants such as soybeans or tomatoes will be placed nearby and monitored for injury.b) To achieve this objective, a dew chamber is required. The dew can be generated over time with a vaporizer. The amount of dew can be varied by the length of time the vaporizer is in the chamber. Herbicides with various adjuvants to be evaluated would be applied to several weed species as weed species would be expected to vary in the retention of dew. Increased or decreased activity of the herbicide treatments would be monitored over time to determine the effect of the various adjuvant in the spray solution.c) Microemulsions of herbicides is not new, nor is it encapsulation. The use of nanotechnology in the formulation of herbicide is novel. The utility provided by this technology provides opportunity for mixing diverse formulations of herbicides and adjuvants. The formulations are prepared and tested in the lab for compatibility prior to evaluation for efficacy in greenhouse trials. Evaluation techniques developed in the last 15 years will be used to evaluate and hopefully discover more effective adjuvants for postemergence herbicides which will increase their effectiveness, economy, and safety in the environment. Structure-function studies using previously published methods (Loose et al., 1999) should provide additional information for the search for more effective adjuvants. Specific attention will be given to adjuvants and formulation techniques that have the potential to overcome antagonistic herbicide interactions.

Progress 02/01/16 to 08/31/20

Outputs
Target Audience:The target audience for this project was the Weed Science scientific community including other Weed Scientists, researchers on adjuvants, herbicide distributors and dealers, herbicide applicators, and crop producers.The target audience for this reporting period was the Weed Science scientific community including other Weed Scientists, researchers on adjuvants, herbicide distributors and dealers, herbicide applicators, and crop producers. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Five undergraduate students were involved in this research. How have the results been disseminated to communities of interest?Information/Results were disseminated by oral presentations at scientific meetings and by publication of scientific papers. Several patents were published. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Available formulations of dicamba were evaluated for volatility from soybean leaves which was greater than volatility from soil. The potential for herbicides injury from volatility could be reduced with certain adjuvants. The potential for herbicides injury from volatility could be reduced with certain adjuvants. The experimental bioassay system for evaluating herbicide vapor loss and injury to nearby plants was shown to be useful. Light dew had little effect in efficacy. Heavy dew resulted in loss of herbicide efficacy due to runoff. Some adjuvants were more effective if dew was present. New water conditioners were evaluated and patents filed.

Publications

Progress 10/01/18 to 09/30/19

Outputs
Target Audience:The target audience for this reporting period was the Weed Science scientific community including other Weed Scientists, researchers on adjuvants, herbicide distributors and dealers, herbicide applicators, and crop producers.The target audience for this reporting period was the Weed Science scientific community including other Weed Scientists, researchers on adjuvants, herbicide distributors and dealers, herbicide applicators, and crop producers. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Two undergraduate students were involved in doing this research. How have the results been disseminated to communities of interest?Information/Results were disseminated by oral presentations at scientific meetings and by publication of scientific papers. One patent has been filed. What do you plan to do during the next reporting period to accomplish the goals?Evaluate new classes of adjuvants as water conditioners and for herbicide vapor reduction.

Impacts
What was accomplished under these goals? Available formulations of dicamba were evaluated for volatility from soybean leaves which was greater than volatility from soil. The potential for herbicides injury from volatility could be reduced with certain adjuvants. The experimental bioassay system for evaluating herbicide vapor loss and injury to nearby plants was shown to be useful. New adjuvants were evaluated and a patent filed.

Publications

• Type: Conference Papers and Presentations Status: Awaiting Publication Year Published: 2019 Citation: Penner D and J. Michael. Dicamba Volatility from Plants and Soils. Proc. NCWSS

Progress 10/01/17 to 09/30/18

Outputs
Target Audience:The target audience for this reporting was the Weed Science scientific community including other Weed Scientist, researchers on adjuvants, herbicide distributors and dealers, herbicide applicators, and crop producers. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Five undergraduate students were involved in doing this research. How have the results been disseminated to communities of interest?Information/Results were disseminated by oral presentations at scientific meetings and by publication of scientific papers. One patent is has been filed. What do you plan to do during the next reporting period to accomplish the goals?Evaluate new classes of adjuvants as water conditioners.

Impacts
What was accomplished under these goals? Available formulations of dicamba were evaluated for volatility from soybean leaves which was greater than volatility from soil. The potential for herbicides injury from volatility could be reduced with certain adjuvants. The experimental bioassay system for evaluating herbicide vapor loss and injury to nearby plants was shown to be useful. Light dew had little effect in efficacy. Heavy dew resulted in loss of herbicide efficacy due to runoff. Some adjuvants were more effective if dew was present. New water conditioners were evaluated and a patent filed.

Publications

• Type: Conference Papers and Presentations Status: Awaiting Publication Year Published: 2018 Citation: Penner D. and J. Michael. Salient features of dicamba volatility from soil. Proc. NCWSS.

Progress 10/01/16 to 09/30/17

Outputs
Target Audience:The target audience for this reporting period was the Weed Science scientific community including other Weed Scientists, researchers on adjuvants, herbicide distributors and dealers, herbicide applicators, and crop producers. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Five undergraduate students were involved in doing this research. How have the results been disseminated to communities of interest?Information/Results were disseminated by oral presentations at scientific meetings and by publication of scientific papers. One patent is has been filed. What do you plan to do during the next reporting period to accomplish the goals?Evaluate new classes of adjuvants as water conditioners.

Impacts
What was accomplished under these goals? The potential for herbicides injury from volatility could be reduced with certain adjuvants. The experimental bioassay system for evaluating herbicide vapor loss and injury to nearby plants was shown to be useful. Light dew had little effect in efficacy. Heavy dew resulted in loss of herbicide efficacy due to runoff. Some adjuvants were more effective if dew was present. New water conditioners were evaluated and a patent filed.

Publications

• Type: Conference Papers and Presentations Status: Awaiting Publication Year Published: 2017 Citation: Penner D. and J. Michael. Factors Affecting Growth Regulator Herbicides Volatility. ASTM, NCWSS.

Progress 02/01/16 to 09/30/16

Outputs
Target Audience: The target audience for this reporting period was the Weed Science scientific community including other Weed Scientists, researchers on adjuvants, herbicide distributors and dealers, herbicide applicators, and crop producers. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Five undergraduate students were involved in doing this research. How have the results been disseminated to communities of interest?Information/Results were disseminated by oral presentations at scientific meetings and by publication of scientific papers. One paten is now published. What do you plan to do during the next reporting period to accomplish the goals?Evaluate new classes of adjuvants as water conditioners.

Impacts
What was accomplished under these goals? The potential for herbicides injury from volatility could be reduced with certain adjuvants. The experimental bioassay system for evaluating herbicide vapor loss and injury to nearby plants was shown to be useful. Light dew had little effect in efficacy. Heavy dew resulted in loss of herbicide efficacy due to runoff. Some adjuvants were more effective if dew was present.

Publications

• Type: Conference Papers and Presentations Status: Awaiting Publication Year Published: 2016 Citation: Penner, D. and J. Michael. Stevia tolerance in herbicides.