Experiments on the greening and senescence arresting effects of cytokinins
Experiments on the greening and senescence arresting effects of cytokinins
Cytokinin is widely found in plants. It can promote cell division, inhibit the activity of some hydrolytic enzymes such as nuclease and protease, so that macromolecular substances are less damaged. Treatment of senescing leaves with cytokinins can prevent the destruction of chlorophyll and extend leaf life.
Put the isolated leaves of plants in the appropriate concentration of cytokinin solution, placed in the dark at 25-30 ℃, the decomposition of chlorophyll in the leaves is slower than the control, proving that schizophyllin has a greening effect.
Operation method
Experiments on the greening and senescence arresting effects of cytokinins
Principle
Cytokinin is widely found in plants. It can promote cell division, inhibit the activity of some hydrolytic enzymes such as nuclease and protease, so that macromolecular substances are less damaged. Treatment of senescing leaves with cytokinins can prevent the destruction of chlorophyll and prolong leaf life. Put the isolated leaves of plants in the appropriate concentration of cytokinin solution, placed in the dark at 25-30 ℃, the decomposition of chlorophyll in the leaves is slower than the control, proving that schizophyllin has a greening effect.
Materials and Instruments
Wheat seedlings Move I. Materials and equipment For more product details, please visit Aladdin Scientific website.
Agonist solution Acetone
Petri dish Measuring cylinder Measuring cylinder Drug balance Small funnel Small scissors Volumetric flask Mace Filter paper 721 Spectrophotometer
Wheat seedlings
8cm diameter Petri dish, 10 ml measuring cylinder, 100 ml measuring cylinder, pharmaceutical balance, small funnel, small scissors, 25 ml volumetric flask, mortar, filter paper, 721 spectrophotometer
Drugs
100pp M agonist solution: 10 mg agonist was dissolved in a small amount of 0.1N HCl and fixed to 100 ml with distilled water.
Acetone, 0.1NHCl, 80%g acetone.
II. Experimental steps
1. 10 ml each of distilled water and 0.05 pp M , 0.5 pp M , 5 pp M , and 50 pp M agonist solution were added to 7 petri dishes. Each treatment was repeated 3 times.
2. Wheat seedlings with uniform growth were selected, the first complete leaf was cut, the tip was cut off 1.5 cm, and the subsequent 3 cm length was cut off. Put 0.500-1.000 g of this cut off into each petri dish. Then put the petri dish in the diffused light culture 1-2 weeks.
3. Take out the wheat leaves from the petri dish, absorb the water with filter paper and put them into the mortar. Put a small amount of quartz sand, a small amount of calcium carbonate and 4-5 ml of 80% acetone into the mortar, carefully grind it into a pulp, filter it into a 100 ml volumetric flask, wash the mortar with 4-5 ml of 80% acetone twice, and then filter the washout. The filter residue and filter paper were put into the mortar again, ground and filtered. This was repeated until the filtrate was free of green color. The filtrate was diluted to 100 ml with 80% acetone.
4. Turn the sensitivity of the 721 spectrophotometer to position 3 and compare the color at 663n M and 645n M with 80% acetone as blank control.
III. Results
Chlorophyll concentration was calculated according to the following formula:
[ch1] = 20.2 x D645 + 8.02 x D663
[ch1] = chlorophyll concentration in M g/liter.
D645: extinction value of chlorophyll solution at 645n M.
D663: extinction value of chlorophyll solution at 663n M.