Question

How would you test the presence of starch in leaves

Answer 1

By using Iodine test

Answer 2

take two potted plant of some kind keep them in dark for 3 day cover a paper or wood stripe your favourite design of leaf tie it keep the plant in Sun for one day plug the leaf having design and open it and the put it iodine solution the uncovered part become violet it shows that the presence of starch in leaf
starch +iodine solution =violet colour