Male Flower of Gnetum
Male strobilus:-
> In Gnetum, the male cones are compact and slender axis-like structures, which are up to 6 cm in length. Each cone is generally a penicle that is either solitary and axillary or fascicled at the apex. The axis of the strobilus bears opposite and connate bracts. Bracts are arranged one above the other to form collars or cupules. There are 6-25 cupules are present, each cupule, staminate flowers are arranged in several definite rings, usually 3 to 6 in number.
> Each mature microsporophyll consists of a stalk bearing two unilocular microsporangia (anthers). The stalk is invested at the base by a perianth.
> In Gnetum ula, 2-4 anthers are there which are formed from microsporangial initial cells. It divides periclinally and anticlinally to form a primary cell wall, tapetal cell, and sporogenous cells. Sporogenous cells later differentiate into spore mother cells. Microspore mother cell forms microspores (pollen grains) through meiosis.
> The wingless pollen grains are liberated by the longitudinal dehiscence of the anthers.