Lecture 14 group 4

Question 1

what do group 4’s inhibit?

Answer 1

Auxin

Question 2

Group 4 application

Answer 2

foliar

Question 3

group 4 targets what type of plant

Answer 3

broadleaves in cereal crops

Question 4

group 4 used as a mix or alone?

Answer 4

extensively in mixtures with other herbicides

Question 5

Group 4 MOA

Answer 5

Mimic plant growth regulator auxin

Question 6

group 4’s - active in basic or acidic state

Answer 6

acid form but formulated otherwise to enhance plant uptake

Question 7

group 4 classes

Answer 7

Phenoxy
Benzoic acid
pyridines
quinoline carboxylic acid
Arypicolinate

Question 8

group 4 Phenoxy chemical names

Answer 8

2,4-D
MCPA
MCPB
Mecoprop
Dichloroprop

Question 9

Group 4 Benzoic acid Chemical name

Answer 9

Dicamba

Question 10

Group 4 Pyridines chemical names

Answer 10

Fluoroxypyr
Picloram
Clopyralid

Question 11

Group 4 QCA Chemicla name

Answer 11

Quinclorac

Question 12

Group 4 Arypicol chemical name

Answer 12

Halauxifen - methyl

Question 13

group 4 target site

Answer 13

Binds to auxin-binding proteins in cytosol or plasma membrane

Question 14

group 4 mimics:

Answer 14

natural plant growth hormone IAA

Question 15

group 4 plant injury

Answer 15

rapid , undifferentiated growth
plants outgrow themselves

Question 16

group 4 dicot injury symptoms

Answer 16

strange growth - “epinasty”
- twisting or downward curling of leaves, stems.

callus formation indicative of group 4

Question 17

group 4 monocot injury symptoms

Answer 17

rapid chlorosis of new leaves

general chlorosis and necrosis

Question 18

group 4 selectivity due to:

Answer 18

differences in morphology
-angle of leaves

Question 19

group 4 monocots or dicots tolerant?

Answer 19

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

Question 20

group 4 soil persistence

Answer 20

varies

late fall applications can injure next year’s crop