what is acropetal and basipetal sucession...?
Rajiv is correct, Acropetal succession refers to the arrangement of flowers on the pedicel in such a way that the new flowers and buds are at the top and the older flowers are at the bottom.
Basipetal arrangement is the opposite of acropetal in the fact that the new flowers and buds are found at the bottom and the older flowers occupy the top levels.
Hope it is clear to you now,
@Rajiv, Good answer, Keep it up!
acropetal succession- it is floral arrangement to form bunch of flowers. In which flowers are arranged so that new flowers are at top and old flowers are at bottom such system is found in racemose type of arrangement. you can see it in gulmohar. this arrangement is for attraction of insects on flowers for pollination so that one insect can pollinate many flowers in a single visit. it also increases flourishing perriod.
basipetal - It relates to the development or maturation of tissues or organs or the movement of substances, such as hormones, from the apex downward toward the base.