Department of Plant Sciences, NDSU
Spring 2010
Instructor:
Dr. Kirk Howatt
470-F Loftsgard Hall
office hours: 8-12 MWF
phone: 1-7209
e-mail: kirk.howatt@ndsu.edu
This course will examine pathways of herbicide entry into the plant and physiological responses to major herbicide modes of action.
I. Introduction
II. Herbicide Absorption and Translocation
a. Foliar
b. Root and shoot
III. Herbicide Metabolism
a. Fate in plants
b. Bio-activation
c. Pathways of metabolism
IV. Herbicide Classification by Mode of Action
a. Growth regulators
b. Photosynthesis inhibitors
c. Pigment inhibitors
d. Cell membrane disruptors
e. Mitosis inhibitors
f. Amino acid inhibitors
g. Acc-ase inhibitors
V. Safeners
VI. Adjuvants
Lecture Reference: Physiology of Herbicide Action. ã 1993. M. Devine, S. Duke, and C. Fedtke. PTR Prentice Hall, 441 pp. Some animations are available online through the Western Society of Weed Science lessons link www.wsweedscience.org.
Lectures: Loftsgard 102, 1:00 – 1:50 p.m., M/W/F
Reading Log and Class Participation 40 pts
Herbicide Focus Paper/Presentation 35 pts
Exam I 100 pts
Exam II 125 pts
Exam III 125 pts
Comprehensive Final Optional
Make-up of missed examinations should be scheduled as soon as the conflict is known.
Final exam score will be an oral format and provide the opportunity to increase the earned grade by one letter grade.
Each student will prepare log of reviewed literature (Journal articles) in preparation for class discussion on the modes of action. An electronic file will be acceptable. Each student should read a minimum of two articles before each of the major modes of action identified under section four of lecture topics are discussed with the class (2X7=14 articles minimum). The log will contain the source, presented in Weed Science format, followed by one or two words to describe the article’s usefulness in explaining the mode of action. A brief summary will be expected that explains findings pertaining to mode of action. Each entry in total does not need to be more than half of a page.
Each student will prepare a short paper describing the technical and chemical properties of an herbicide introduced within the last few years. The paper should include chemical properties and how these relate to behavior in the environment and plants. Information could include pathway reactions, time course, fate of metabolites, evidence for selectivity or use patterns. Length is not mandated. Please use 10 or 12 pt Arial font, 1-inch page margins, and 1.5 line spacing. Students will present information in class.
Course Grading:
Expectations will not exceed those provided below.
92% and above - A
82% to 90% - B
below 82% - C
Students with Disabilities are asked to inform the instructor so that arrangements can be made in cooperation with the Office of Disability Services to provide appropriate services.
The Honor Code will be followed in this course. Examinations are given according to the policies of the Honor System within the College of Agriculture (http://www.ag.ndsu.nodak.edu/colag/honor.htm). University Guidelines for academic honesty are outlined in NDSU University Senate Policy, Section 335: Code of Academic Responsibility and Conduct (http://www.ndsu.nodak.edu/policy/335.htm).
Tentative Lecture Schedule:
January 13 – Introduction
15 – Chemical properties
18 – MLK Holiday
20 – Absorption
22 – Absorption
25 – Translocation
27 – Translocation
29 – Metabolism
February 1 – Metabolism
5 – Exam I
10 – Photosynthetic inhibitors
12 – Photosynthetic inhibitors
15 – Presidents Day Holiday
17 – Photosynthetic inhibitors
19 – Pigment inhibitors
22 – Pigment inhibitors
24 – Membrane disruptors
26 – Membrane disruptors
March 1 – Mitosis Inhibitors
3 – Exam II
8-12 – WSWS meeting
15-19 – Spring Break
22 – Amino acid synthesis inhibitors
24 – Amino acid synthesis inhibitors
26 – Amino acid synthesis inhibitors
29 – ACC-ase inhibitors
31 – ACC-ase inhibitors
April 2-5 – Recess
7 – Miscellaneous
9 – Safeners
12 – Adjuvants
14 – Exam III
16 – Topic Discussion