There are five cultivated species of the genus
Cucurbita: C. pepo
,
C. moschata
,
C. maxima
,
C. argyrosperma
, and
C. ficifolia
.
Cucurbita
is one of the most morphologically variable genera in the plant kingdom. Breeding of
Cucurbita
has played a key role in the variety and productivity of cultivars available to growers and consumers today. In addition to traditional plant breeding methods of transferring virus‐resistance alleles from wild to cultivated species of
Cucurbita
, scientists have developed and commercialized genetically engineered virus resistance in
C. pepo
. The center of origin for
Cucumis
species is likely Africa for the wild species, but initial sites of domestication for
C. melo
are likely in the Middle East. On the other hand,
C. sativus
may have originated in Africa, China, India, or in the Near East with domestication occurring later throughout Europe. Melon and cucumber's improved varieties have thus far been derived through traditional breeding, which has accomplished a wide range of improvements, including yield and disease resistance. Watermelon was thought to have originated in southern Africa. Most cultivated or edible watermelons belong to the species
Citrullus lanatus
. Over the past century, conventional breeding has tremendously improved earliness, plant architecture, fruit yield, quality, diversity, disease resistance, and shipping quality.