PLANT GROWTH MEASUREMENT

Requirements

Small plots/boxes, meter rule and seeds of beans (or green grams, peas, maize),

Procedure

1. Place some soil in the box or prepare a small plot outside the laboratory.
2. Plant some seeds in the box and place it in a suitable place outside the laboratory (or plant the seeds in your plot).
3. Water the seeds daily.
4. Observe the box/plot daily and note the day the seedlings emerge out of the soil.
5. .Measure the height of the shoot from the soil level up to the tip of the shoot.
6. Repeat this with four other seedlings. Work out the average height of the shoots for this day.
7. Repeat procedure 5 every three days for at least three weeks.
8. Record the results in a table form.
9. On the same seedlings measure the length of one leaf from each of the five seedlings (from leaf apex to its attachment on the stem).
10. Calculate the average length of the leaves and record in the table.
11. Plot a graph of the height of the shoot against time. On the same axes plot length of leaf against time.
12. Compare the two graphs drawn.

Growth and Development In Plants

The main growth and development phase in plants begins with the germination of the mature seed. Seeds are of two kinds depending on the number of cotyledons or embryo leaves.

Practical Activity

To investigate structural differences between monocotyledonous and dicotyledonous seeds –

Requirements

Bean seeds and maize grains which have been soaked overnight. Scalpel or razor blades, iodine solution, Petri-dish and hand lens.

Procedure

1. Using a scalpel or razor blade make longitudinal sections (LS) of both the bean seed and the maize grain.
2. Observe the LS of the specimens using a hand lens.
3. Note any structural difference between the specimens.
4. Draw the LS of each specimen and label.
5. Puta drop of iodine solution on the cut surfaces of both specimens.
6. Note any differences in colouration with iodine on the surfaces of the two specimens.
7. On your diagrams indicate the distribution of the stain.

Account for the difference in distribution of the colouration with iodine in the two specimens.

EVALUATION

1. How do you calculate the fresh weight of a plant?
2. What is fresh weight and dry weight in plants?
3. How do you find the dry weight of a plant?
4. How do you measure plant growth?
5. How do you calculate leaf weight?
6. How much do plants weigh?
7. What is the weight of a leaf?
8. How is leaf area ratio calculated?
9. How do you measure the diameter of a plant?
10. How do we calculate growth rate?