4.14 To investigate the effect of IAA growth regulator on plant tissue

Before you start get or make a copy of this
Table of results for Roots, and …
Dish Concentration of IAA Length of Roots (mm)
A
B
C
D
E
F
G
H
I
J (Control)
(mg/litre)
100.000000
(ppm) Seed 1 Seed 2 Seed 3 Seed 4 Seed 5 Seed 6 Seed 7 Seed 8
10.000000
1.000000
0.100000
0.010000
0.001000
0.000100
0.000010
0.000001
0
10 -3
10 -4
10 -5
10 -6
0
10 2
10 1
10 0
10 -1
10 -2
Total
Length
(mm)
0
0
0
0
0
0
0
0
0
0
Averag e
Length
(mm)
% increase or decrease

Before you start get or make a copy of this
Table of results for Shoots
Dish Concentration of IAA Length of Shoots (mm)
(mg/litre)
F
G
D
E
A
B
C
H
I
J (Control)
100.000000
10.000000
1.000000
0.100000
0.010000
0.001000
0.000100
0.000010
0.000001
0
(ppm) Seed 1 Seed 2 Seed 3 Seed 4 Seed 5 Seed 6 Seed 7 Seed 8
10 2
10 1
10 0
10 -1
10 -2
10 -3
10 -4
10 -5
10 -6
0
Total
Length
(mm)
0
0
0
0
0
0
0
0
0
0
Averag e
Length
(mm)
% increase or decrease

Step 1
Label eight petri dishes 10 2 , 10 1 ,
1, 10 -1 , 10 -2 , 10 -3 , 10 -4 and control.

Step 2
Add 10 ml of the IAA solution to the dish labelled 10 2 .

Step 3
Using a different syringe, add 9 ml of water to each of the other dishes.

Step 4
Using a dropper, remove 1ml of solution from the 10 2 dish and add it to the 10 1 dish.

Step 5
Stir the solution using the dropper. Repeat for the remainder of the dishes (1, 10 -1 , 10 -2 , 10 -3 and 10 -4 ), using a different dropper each time.

Step 6
Discard 1ml of liquid from the dish labelled 10 -4 .

Step 7
Place an acetate grid on the lid of each petri dish. Place 5 radish seeds along the cross lines.

Step 8
Place filter paper on top of the seeds. Spread cotton wool on top of the filter paper.

Step 9
Put the base of each petri dish on its lid. Secure the dishes and incubate vertically at 25 °C for 2-3 days.

Step 10
Measure the lengths of roots and shoots of each seed using the acetate grid.

Results & calculations
Calculate the average length of the stems and roots at each concentration and the percentage stimulation or inhibition.
Chart and graph the results

Root results
Dish Concentration of IAA Length of Roots (mm)
A
B
C
D
E
F
G
H
I
J (Control)
(mg/litre)
100.000000
10.000000
1.000000
0.100000
0.010000
0.001000
0.000100
0.000010
0.000001
0
(ppm) Seed 1 Seed 2 Seed 3 Seed 4 Seed 5 Seed 6 Seed 7 Seed 8
10 -2
10 -3
10 -4
10 -5
10 2
10 1
10 0
10 -1
10 -6
0
Total
Length
(mm)
Averag e
Length
(mm)
0 #DIV/0!
0 #DIV/0!
0 #DIV/0!
0 #DIV/0!
0 #DIV/0!
0 #DIV/0!
0 #DIV/0!
0 #DIV/0!
0 #DIV/0!
0 #DIV/0!
% increase or decrease
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!

Shoot results
Dish Concentration of IAA
(mg/litre)
Length of Shoots (mm)
(ppm) Seed 1 Seed 2 Seed 3 Seed 4 Seed 5 Seed 6 Seed 7 Seed 8
Total
Length
(mm)
G
H
E
F
C
D
A
B
I
J (Control)
100.000000
10.000000
1.000000
0.100000
0.010000
0.001000
0.000100
0.000010
0.000001
0
10 -2
10 -3
10 -4
10 -5
10 2
10 1
10 0
10 -1
10 -6
0
Averag e
Length
(mm)
0 #DIV/0!
0 #DIV/0!
0 #DIV/0!
0 #DIV/0!
0 #DIV/0!
0 #DIV/0!
0 #DIV/0!
0 #DIV/0!
0 #DIV/0!
0 #DIV/0!
% increase or decrease
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!

50
0
0
-50
-100
200
150
100
-150
1
Expected graph
Effect of varying auxin concentrations on Root and Shoot Development
Root Shoot
2 3 4 5 6 7
Auxin concentration (parts per million)
8 9 10

END