Stable form of papaya is

Stable form of papaya is Pistillate. Papaya is a polygamous plant with three basic types of flowers viz. staminate, pistillate and hermaphrodite (bisexual). Of these, only pistillate is stable, whereas flowers of hermaphrodite and male vary in sex expression under different environmental conditions.
The pistillate form of papaya has a flower that lacks stamens is pistillate. The pistillate flower of papaya is a pleurogynous unisexual form derived intraspecifically from a perigynous bisexual ancestor. It is a morphological anomaly in which the ovary consists of two cycles of carpels.