Species Description
Merremia tuberosa is a long, climbing vine. Its leaves are simple and the blades are circular in outline, 6-16 cm long and wide, the base is cordate, and margins are palmately 5-7 lobed almost to the base. The lobes are 8-20 cm long, 9-20 cm wide, ovate, 3-9 cm long, 1-5 cm wide, and leaf margins are entire. Its stems are basally woody, perennial, twining, and glabrous. Flowers usually occur in clusters and fully bloom in sunlight and close under cloudy conditions and in the dark. The corolla is yellow, glabrous, funnelform, contortiplicate, enclosed by the sepals in bud, and comprised of 4 petals 5-6 cm long. It has 3 petioles which are 6-18 cm long and glabrous. Its pedicels are 15-18 mm long, claviform, glabrous, and enlarge in fruit. Its sepals are unequal, with the outer two longer than the inner three. They are oval to almost orbicular, with a rounded apex, membranous apically, somewhat herbaceous basally, and 23-25 mm long. Its sepals equally enlarge in fruit. The inner three are oblong, 12-20 mm long. Its filament is unequal, 2.5-3 cm long, glandular, and pubescent. The pistil is glabrous, 4-locular, and the stigma is globose. It has tuberous taproots. The fruits are globose to depressed globose and 3-3.5 cm in diameter. The calyx is accrescent, with fruiting sepals divergent but supporting the fruit. 1-4 seeds occur per fruit and are black to dark-brown, ovoid, 1.5-2 cm long, smooth surfaced, and covered with short, erect, puberulent indumentum (Austin, 1998; Motooka et al, 2003).
Lifecycle Stages
Merremia tuberosa is a perennial vine that produces bright yellow morning-glory-like inflorescences in the late fall. Fruits occur abundantly in early winter. By late December and early January die backs occurs. Its seeds remain viable for several years and germinate readily even in conditions of low light (Langland & Stocker, 2001; PIER, 2008).
Uses
The roots of Merremia tuberose contain resins that were formerly used across the tropics and in Europe as laxatives. Now plants are grown for their flowers and ornamental fruits that are used by florists. Its grated root was historically found useful for those that have swollen bellies and whose intestines rumble. A mixture was also drunk while fasting, to purge, and to lower fever (Austin, 1998).
Habitat Description
Merremia tuberosa is known to grow in mesic forests from 0-1,400 m elevation. It is a climbing vine that grows over trees or other surfaces and prefers high levels of sunlight. It is also reported to require fertile, well-drained soils (Smith, undated; PIER, 2008).
Reproduction
Merremia tuberosa reproduces primarily through seed production and also by vegetative fragmentation. It produces an abundant seed set in the winter that germinate readily (PIER, 2008; Langland & Stocker, 2001).
Pathway
Merremia tuberosa was spread through as a medicine throughout Europe when it was discovered in Mexico, and subsequently through horticulture trade around the world. The roots contain resins that formerly were used across the tropics and in Europe as laxatives. Now it is grown and introduced for their flowers and ornamental fruits that are used by florists (Austin, 1998).
Principal source: Austin, Daniel F. 1998. Xixicamatic or wood rose (Merremia tuberosa, Convolvulaceae): Origins and dispersal. Economic Botany. 52(4). Oct.-Dec., 1998. 412-422.
Pacific Islands Ecosystems at Risk (PIER), 2008. Merremia tuberosa (L.) Rendle, Convolvulaceae
Smith, Clifford W., Undated. Impact of Alien Plants on Hawaiis Native Biota
Compiler: Comité français de l'UICN (IUCN French Committee) & IUCN SSC Invasive Species Specialist Group (ISSG)
Review: Dr. Daniel F. Austin, Center for Sonoran Desert Studies, Arizona-Sonora Desert Museum
Publication date: 2010-07-16
Recommended citation: Global Invasive Species Database (2024) Species profile: Merremia tuberosa. Downloaded from http://iucngisd.org/gisd/speciesname/Merremia+tuberosa on 21-12-2024.