In which one of the following, both autogamy and geitonogamy are prevented?
Wheat
Papaya
Maize
Castor
List three strategies that a bisexual chasmogamous flower can evolve to prevent self pollination (autogamy).
Give scientific reasons : Outbreeding devices increase fertility.
$A$ : Continued self-pollination checks inbreeding depression.
$R$ : Pollen release and stigma receptivity are synchronised.
Flowers are unisexual in
A plant with both male and female flowers borne over it is