Lecture 14 group 4 Flashcards
what do group 4’s inhibit?
Auxin
Group 4 application
foliar
group 4 targets what type of plant
broadleaves in cereal crops
group 4 used as a mix or alone?
extensively in mixtures with other herbicides
Group 4 MOA
Mimic plant growth regulator auxin
group 4’s - active in basic or acidic state
acid form but formulated otherwise to enhance plant uptake
group 4 classes
Phenoxy
Benzoic acid
pyridines
quinoline carboxylic acid
Arypicolinate
group 4 Phenoxy chemical names
2,4-D
MCPA
MCPB
Mecoprop
Dichloroprop
Group 4 Benzoic acid Chemical name
Dicamba
Group 4 Pyridines chemical names
Fluoroxypyr
Picloram
Clopyralid
Group 4 QCA Chemicla name
Quinclorac
Group 4 Arypicol chemical name
Halauxifen - methyl
group 4 target site
Binds to auxin-binding proteins in cytosol or plasma membrane
group 4 mimics:
natural plant growth hormone IAA
group 4 plant injury
rapid , undifferentiated growth
plants outgrow themselves
group 4 dicot injury symptoms
strange growth - “epinasty”
- twisting or downward curling of leaves, stems.
callus formation indicative of group 4
group 4 monocot injury symptoms
rapid chlorosis of new leaves
general chlorosis and necrosis
group 4 selectivity due to:
differences in morphology
-angle of leaves
group 4 monocots or dicots tolerant?
monocots generally tolerant, except quinclorac
retention- lower in monocots
absorption - slower in monocots
translocation - slower in monocots
metabolism - faster in monocots
monocots do not have cambium layer which is sensitive to crushing in dicots
group 4 soil persistence
varies
late fall applications can injure next year’s crop
