چكيده لاتين :
A sample collected from the citrus orchards of the Sari Township, Mazandaran province (N Iran), was determined as Araujia sericifera Brot. (Apocynaceae), according to Markgraf (1972). This species and the genus Araujia, is new to Iran and the region covered by Flora Iranica (Rechinger 1970, 1974).
A. sericifera, a native plant of the South America, was first introduced to Europe, the United States and other region as an ornamental plant. Nowadays, it is regarded as an invasive plant or weed in many countries. The European Plant Protection Organization included the species in its Alert List in 2008 and in its Observation List of potentially invasive plants in 2012 (Anonymous 2012). The species is classified as a high-risk plant in the United States (Anonymous 2013), important weed in parts of New Zealand (Popay et. al. 2004) and potentially most serious weed in some provinces of Australia (Anonymous 2013).
The global distribution of this plant includes South America, North America, United States, Europe (France, Italy, Greece and Portugal), South Africa and Australia (Popay et. al. 2004).
Araujia sericifera has a very rapid growth. It forms dense colonies when it enters a region. The plant has a very high seed production rate. The seeds keep their potency for five years and are scattered through wind, water and clothes (Spellman & Gunn 1976).
The plant is habituated mainly in the margins of lakes, rivers and streams, dry river beds, forests, farmlands, citrus groves, orchards (vineyards, citrus fruits, berries, olives etc.), urban green spaces, road and rail sides and wastelands (EPPO 2012(.
This climber weed, which has a highly dense and heavy foliage, settles beside the host trees and usually grows in two years so densely that it covers the canopy of the host trees and competes for water, nutrients and light. It kills individual branches by girdling. Significant infestations reduce fruit yields and interfere with tree maintenance and pruning (Anonymous 2012).
The plant has poisonous milky sap and can trap and kill insects using its bell-shaped petals. Hence it is called ʹʹThe Cruel Plantʹʹ (Popay et. al. 2004). A short description of plant is as follows.
Stems twining, slender, woody, finely hairy. Leaves opposite, simple, oblong-ovate, acute, 3–6 cm long and 1–2.5 cm wide), truncate at bases, upper surface glabrous or sparsely haired, glossy, dark green, the lower surface densely haired, fine, gray-green. Petioles 1–1.7 cm long. Fruits egg-shaped, pendant, 10 cm long, 4–5 cm in diameter. Seeds numerous, dark brown to black, 5–6 mm, with distinctive glands scattered on the surface, topped with deciduous white silky hairs (Fig. 1).
Material examined: Iran, Mazandaran province, Sari, Citrus orchard, 2.10.2013, Zand (62662 IRAN).
