Bindweed

Bindweed — The Convolvulaceae, known commonly as the bindweed or morning glory family, is a group of about 60 genera and more than 1,650 species of mostly herbaceous vines, but also trees, shrubs and herbs.

They can easily be recognized by their funnel-shaped radially symmetrical flowers. These have 5 sepals, a corolla of 5 united petals and 5 stamens. The flowers are hypogynous (= having a superior ovary). The stem of these plants is usually winding, hence its Latin name (convolvere = to wind). The leaves are simple and alternate, without stipules. The fruit is a capsule with one to four seeds (sometimes even more), or a berry or a nut.

The leaves and starchy tuberous roots of some species are used as foodstuffs (e.g. sweet potato and water spinach), and the seeds are exploited for their medicinal value as purgatives. Some species contain ergoline alkaloids that are likely responsible for the use of these species as ingredients in psychedelic drugs (e.g. ololiuhqui). The presence of ergolines in this plant family is apparently due to infection by fungi related to the ergot fungi of the genus Claviceps. A recent study of the Convolvulaceae species, Ipomoea asarifolia, and its associated fungi showed that the presence of a fungus, identified by DNA sequencing of 18s and ITS ribosomal DNA and phylogenetic analysis to be closely related to fungi in the family Clavicipitaceae, was always associated with the presence of ergoline alkaloids in the plant. The identified fungus appears to be a seed-transmitted obligate biotroph growing epiphytically on its host. This finding strongly suggests that the unique presence of ergoline alkaloids in some species of the family Convolvulaceae is due to symbiosis with clavicipitaceous fungi.