Cucurbitaceae - Gourds
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The Cucurbitaceae is a medium-sized family of dicotyledenous annual flowering herbs with around 119 genera and over 800 species, mostly from warm climates. The family takes its name from the genus The order takes its name from the genus Cucurbita (squashes, pumpkins). Bryonia has two hardy species from England and Europe. Many species have 5-angled climbing or prostrate stems, often roughened with trichomes, carrying alternate palmately 5-lobed, veined leaves and coiled tendrils. Cucurbitaceae typically have unisexual yellow or white flowers with 5-fold symmetry and pointed petals, sometimes with petals fused into a funnel, and may be monoecious or dioecious. Fruits are berries (pepo) but may be very large and bottle-shaped containing many seeds, or an explosively dehiscent capsule.
A few members of the family are regarded as invasive weeds.
The Cucurbitaceae includes many important food plants (cucumber, melon, pumpkin, squash) as well as useful inedible species (bottle gourds, loofah, ornamental gourds). Members of this family have been cultivated for at least 10,000 years. Some species e.g. Bryonia are also considered to have medicinal properties.
Cucurbitacins (tetracyclic triterpenoids and their glycosides) occur commonly in this family and impart a bitter flavor, discouraging or even poisoning herbivores. Cucurbitacins, among the most bitter substances known, have been investigated as anticancer agents, insecticides and beetle attractants.
Most cultivated Cucurbitaceae have been selected to produce low levels of cucurbitacins although the bitterness of cultivated species may increase in response to environmental stress such as heat or shortage of water. The concentration of cucurbitacins is generally highest in roots and fruit. Asian bitter melons are grown especially for this bitter flavour.
While many species may be considered to have a degree of succulence, species of Coccinia, Corallocarpus, Cyclantheropsis, Gerrardanthus, Ibervillea, Kedrostis, Melothria, Momordica, Odosicyos, Seyrigia, Xerosicyos, and Zehneria are generally considered worthy of cultivation as succulent or caudiciform plants.
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Bryonia dioica (White Bryony)
White Bryony is the only native English cucurbit. This climbing plant of hedgerows and woodland margins is found in England as far North as Yorkshire and in Europe to the Middle East. From a large forked fleshy perennial root arises a large annual vine, with an angular stem bearing alternate large simple triangular leaves with notched margins and long tendrils arising from the leaf axils. The English species Bryonia dioica has small white flowers with 5 petals, followed by red berries with a thin skin over one or two seeds. A similar European species Bryonia alba has black berries. Both male and female flowers occur on the same plant.
White Bryony is of historical interest as its forked root was often used as a substitute for the magical root, mandrake, which does not grow in Great Britain and had to be imported from the continent. The more similar to the human form, the more valuable the root. A suitable shape was sometimes encouraged by making the root grow through earthenware moulds.
The tubers are very poisonous. White Bryony contains the irritant alkaloid bryonine, useful in animal husbandry and as a medical "cure-all" including a 14th century treatment for leprosy. Modern herbal and homeopathic preparations are still in use.
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Bryonia dioica |
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Note: the English "Black Bryony" is from the wild yam family, with different toxic and herbal properties.
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Plant Families with Succulent Species 