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EFFECTS AND PRACTICAL APPLICATIONS OF HORMONES/GROWTH SUBSTANCES

 
AUXIN

1) Tropism - response of plants to environmental or physical stimuli.

    a) phototropism- response to light

    b) geotropism - response to gravity

    c) thigmotropism - response to touch

2) Apical dominance - determined by apical bud, partly due to auxin produced

3) Fruit set - low concentrations stimulate

4) Fruit or flower thinning - high concentrations cause

5) Herbicides - 2,4-D at high concentrations

6) Adventitious root formation

    a) stem and leaf cuttings

    b) tissue culture
 
 

 

CYTOKININ

1) Leaf aging or abscission - may delay

2) Seed germination - may overcome dormancy or stimulate germination

3) Adventitious shoot formation

    a) leaf and root cuttings

    b) tissue culture