Citrullus colocynthis

Citrullus colocynthis, with many common names including colocynth, bitter apple, bitter cucumber, desert gourd, egusi, vine of Sodom, or wild gourd, is a desert viny plant native to the Mediterranean Basin and Asia, especially Turkey (especially in regions such as İzmir), Nubia and Trieste. It resembles a common watermelon vine but bears small, hard fruits with a bitter pulp. It originally bore the scientific name Colocynthis citrullus, but is now classified as Citrullus colocynthis.
The flowers are yellow and solitary in the axes of leaves and are borne by yellow-greenish peduncles. Each has a subcampanulated five-lobed corolla and a five-parted calyx. They are monoecious therefore the male (stamens) and the female reproductive parts (pistils and ovary) are borne in different flowers on the same plant. The male flowers’ calyx is shorter than the corolla. They have 5 stamens, 4 of which are coupled and 1 is single with monadelphous anther. The female flowers have 3 staminoids and a 3-carpels ovary. The two sexes are distinguishable by observing the globular and hairy inferior ovary of the female flowers.


Citrullus colocynthis is a perennial plant that can propagate both by generative and vegetative means. However, seed germination is poor due to the extreme xeric conditions, therefore the vegetative propagation is more common and successful in nature. In the Indian arid zone the growth takes place between January and October but the most favorable period for the vegetative growth is during summer, which coincides with the rainy season. The growth declines as soon as the rains and the temperature decrease and almost stops during the cold and dry months of December and January.

Colocynth prefers sandy soils and is a good example of good water management which may be useful also on research to better understand how desert plants react to water stress.
To enhance production, an organic fertilizer can be applied.
Colocynth is also commonly cultivated together with cassava (intercropping) in Nigeria.

Cultivated colocynth suffers of climatic stress and diseases such as cucumber mosaic virus, melon mosaic virus, Fusarium wilt, etc. as any other crop. To improve it, a relatively new protocol for regeneration has been developed with the aim of incorporating disease and stress resistance to increase yield potential and security avoiding interspecific hybridization barriers.