Yuncker and many other workers separated Cuscuta approximate from Cuscuta europaea mainly on the basis of capsule Character, i.e. depressed in Cuscuta approximate and conical in Cuscuta europaea. However there is a remarkable variation in the depression of the capsule, size of the petals, and shape of the scales, number of the flowers in the clusters, size of the pedicel. We have examineds more than 200 specimens including a few specimens from A, BM, E, K, MICH, O and E which were previously identified as Cuscuta europaea and Cuscuta approximate. But in our opinion it is not possible to separate Cuscuta europaea from Cuscuta approximate.
Tutin, l.c., separated Cuscuta approximate by having the calyx tube golden-yellow, shiny, and reticulate. But there is continuous variation of these characters. Plitmann, l.c., separated Cuscuta europaea from Cuscuta approximate by the presence of usually 4-merous flowers, style and stigmas shorter than ovary whereas in the latter taxon the flowers are infrequently 4-5 merous, the stigma and style usually longer or rarely shorter than ovary. A remarkable variation is found in the number of petals and sepal lobes: mostly flowers have 5 petal and sepal lobes, but a few flowers, even from the same cluster, have 4 or 6 petal and sepal lobes. Variation also exists in the colour, size and degree of bending of the style and. stigma. In the specimens we have examined the character combination used by Plitmann to separate Cuscuta approximate and Cuscuta europaea breaks down, and these two taxa cannot be recognized as two distinct species.
We have examined the type specimen of Cuscuta kotschyana [S. Persia, Kuh-Daena, Kotschy 749, (G, O!)] and could not find any reasonable difference between it and Cuscuta europaea. As mentioned above there is a wide range of varialion within Cuscuta europaea. The characters of the type specimen of Cuscuta kotschyana fit well within the variation range of Cuscuta europaea.
We have also examined specimens of Cuscuta planijlora Tenore, and are unable to find any significant differences between it and Cuscuta europaea; the only minor difference we have noticed is that in Cuscuta planifora the flowers are slightly more compactly arranged in clusters than in Cuscuta europaea. Engehnan also considered; Cuscuta planifora and Cuscuta approximate to be conspecific.
Cuscuta brevistyla A. Braun. ex A. Rich, is also not recognized as a separate species. Yuncker 1932 & 1964, mentioned in his descriptions of Cuscuta brevistyla that "considerable variation is observed in this species which in many of its characters resembles Cuscuta approximate (synonym of Cuscuta europaea) and Cuscuta planiflora”. He had separated Cuscuta brevistyla from Cuscuta approximate and Cuscuta planiflora on the basis short style and less turgid perianth parts. However, these characters do not apperar to be significant enough to separate the taxa. Most probably previous taxonomists have separated Cuscuta brevistyla from Cuscuta europaea because of the small number of collections available to them.
Cuscuta europaea, the greater dodder[1] or European dodder, is a parasitic plant native to Europe, which belongs to the family Convolvulaceae, but was formerly classified in the family Cuscutaceae. It grows on Asteraceae, Cannabaceae, Chenopodiaceae, Fabaceae, Urticaceae and other herbaceous plants, including garden plants such as Coleus and Impatiens, and more occasionally on Humulus.[2] It is a notable parasite of lucerne (Medicago sativa). In many regions, including the Nepal Eastern Himalayas, this species are used as traditional medicine to treat hepatic diseases.[3]
The long thin stems of C. europaea are yellowish or reddish. They have an inflorescence that is produced laterally along the stems, the flowers are arranged in compact glomerules with few to many flowers. The pedicels are up to 1.5 millimetres (0.059 in) long. The 1.5 mm calyx is cup-shaped with 4 or 5 sepals that are triangular-ovate in shape. The 2.5–3 millimetres (0.098–0.118 in) corolla is pink, with 4 or sometime 5 lobes. The corolla remains after anthesis and is often reflexed. The stamens are inserted below sinus and the filaments are longer than the anthers. The anthers are ovate-circular with very thin scales. The ovary is subglobose with 2 styles. The stigmas are divergent or curved. The 3 mm wide, rounded seed capsule, is capped by the withered corolla. Each capsule often has 4, pale brown, elliptic, seeds that are 1 mm long.[4]
Cuscuta europaea can now be found in Japan and Algiers,[5] as well as N Africa, W Asia and Europe.[6] In India and Pakistan, the species occurs in the Himalayas, stretching from Kashmir to Sikkim on an altitude of 3,600 metres (11,800 ft).[7]
Derived from the Arabic word kechout, Cuscuta was the name used for this plant by Rufinus, a thirteenth-century botanist. The specific epithet europaea means 'European' or 'of Europe'.[8]
C. europaea was introduced to North America,[9] where it is considered to be an invasive species in Maine.[10] In 1979 Holm described the weed as 'serious' in Afghanistan and Poland while it was 'principal' in Czechoslovakia and the Soviet Union. P. Wolswinkel, during the same year, also took note on its invasiveness, as the species was feeding on faba bean. In 1983, Wolswinkel and Ammerlaan had seen another damage that was caused by this plant, after finding dry matter and ash in the nettle and Aegopodium podagraria species. The species which were affected had 8.5% less chlorophyll, which C. europaea drains out of its host plants, as was suggested by Gal'vidis in 1993. In Italy, former Yugoslavia and eastern Europe the species was known to infest sugar beet as well being poisonous to livestock, such as horses.[4]
Cuscuta europaea, the greater dodder or European dodder, is a parasitic plant native to Europe, which belongs to the family Convolvulaceae, but was formerly classified in the family Cuscutaceae. It grows on Asteraceae, Cannabaceae, Chenopodiaceae, Fabaceae, Urticaceae and other herbaceous plants, including garden plants such as Coleus and Impatiens, and more occasionally on Humulus. It is a notable parasite of lucerne (Medicago sativa). In many regions, including the Nepal Eastern Himalayas, this species are used as traditional medicine to treat hepatic diseases.