add iodine to destarched leaf ,which has been partly covered.The part of the leaf containing starch will turn blue-black. The parts NOT containing starch, will turn brown.
Add few drops of iodine on the de-starched & keep it in a petridish.The colour of the leaf will turn blue-black.
add iodine to destarched leaf.The part of the leaf containing starch will turn blue-black. The parts which donot contain starch, will turn brown.
use iodine solution - the leaf turns blue if starch is present
destrach a leaf.plce it in sunlight in sunlight for 3 hrs . dip the solution in boiled water to denature the enzyme.place it in a alcohol water bath till the alcohol boils. now rinse it with iodine solution. the parts that contain starch would turn blue-black.
A Simple Experiment to Test if Starch is Present in Leaves:
Place a potted plant in a dark room by covering or wrapping a part or portion of a leaf. Leave this palnt for a day or two. The next day, take the plant and place it in sunlight for a few hours. Next, take the leaf which was partly covered by black paper, remove the black paper and do the test of starch by adding two drops of dilute iodine solution to it. You will see, that the portion of the leaf which was not covered by the black paper will turn into blue-black colour. But, you will see that the portion of the leaf covered by black paper will not change its colour. This indicates that the leaf which was not covered by the black paper has prepared food, i.e. it has prepared starch.