Which one of the following plants shows vexillary aestivation and diadelphous stamens?
Pisum sativum
Allium cepa
Solanum nigrum
Colchicum autumnale
Vexillary aestivation: - It is a unique arrangement where the other smaller petals are covered by one large petal. The larger petal is called the vexillum or standard while the other two curved petals laterally positioned are called wings. The two inmost, boat-shaped petals are called reels. E.g.: - In pea.
Stamens are the male reproductive structure of flowers. They are either free or united, when they are free, they are known as polyandrous. When they are united, they are referred to according to the number of bunches they form: -
So, the pea (Pisum sativum) is the plant that shows both vexillary aestivation 8 amadelphous stamens.
Hence the correct option is (a).