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

    a) phototropism- response to light (orchid in window)

    b) geotropism - response to gravity (positive and negative)

    c) thigmotropism - response to touch (video of vine) 

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

3) Flower and Fruit set - low concentrations can stimulate by substituting for pollination

4) Fruit or flower thinning - high concentrations cause (but usually use mechanical, machine @ 40 sec, hand  @ 1 min)

5) Herbicides - 2,4-D at high concentrations - (distorted, twisted leaves and shoot tips) 

6) Adventitious root formation

    a) stem and leaf cuttings (stem cuttings, rooting powder,)

    b) tissue culture (adventitious roots from callus and adv shoots)
 
 

1) Leaf aging or abscission - may delay

3) Flower and Fruit set - low concentrations stimulate (flower set spray)

2) Seed germination - may overcome dormancy or stimulate germination

3) Adventitious shoot formation

    a) leaf and root cuttings (African violet, begonia)

    b) tissue culture (adventitious shoots from callus)

1) Rosette or dwarf plants - lack of endogenous GA often causes

• growth retardants - chemicals that block GA synthesis; are used in greenhouse and
  
                                bedding plant production to produce compact plants (poinsettia height control, Impatiens)

3) Fruit size - increases size of seedless grapes

4) Bud dormancy - may overcome and substitute for cold treatment

5) Seed germination - may increase or speed up

6) Sex expression - favors staminate flower formation on monoecious plants (stamate flowers cucumber)
 

Sources of ethylene: ripening fruit, combustion faulty heater

1) Fruit ripening - stimulates in many fruits, ex. banana (ripening room, stages of ripening, home banana rack)

2) Flowering - triggers flowering in some bromeliads, ex. (epiphyte, bromeliad, pineapple)

3) Flower longevity - causes senescence (death) of cut flowers (storing flowers and fruit together is a no! no!)

4) Leaf abscission (leaf drop) - causes in some plants

5) Leaf epinasty (curling and contortion of leaves) - causes in some plants (tomato, malfunctioning heater)

6) Sex expression - favors pistillate flower formation on monoecious plants (pistillate flowers cucumber)
  

1) Dormancy - causes bud or seed dormancy

2) Leaf abscission (leaf drop) - may cause in some plants

3) Stomata - causes stomata to close (a response to drought stress)