Solanum elaeagnifolium, an increasing problem in Greece
Solanum elaeagnifolium (Solanaceae, EPPO A2 List) has spread during the last 20 years across Greece, especially in Thessaloniki and Chalkidiki because of the intensive human activities (constructions of new roads, building or agricultural activities). A significant proportion of fields with arable, horticultural and perennial crops, as well as waste lands and roadsides, have been infested by this weed.
Mature berries of the plant contain high levels of solanine and solanosine which are toxic to livestock. Large infestations can reduce harvest yields by competing for nutrients and soil moisture, and have allelopathic effects especially in cotton fields. S. elaeagnifolium develops colonies from extensive systems of creeping horizontal and deep vertical roots, both of which produce new shoots. Fruits and seeds disperse via agricultural activities, water, mud, soil movement and animals. Colonies of
S. elaeagnifolium are difficult to control by mechanical or biological methods because no biocontrol agent is currently registered against this plant. In Greece, the only method used against S. elaeagnifolium in irrigated summer and perennial crops consists of weekly mowing that prevents the production of new shoots or the establishment of new seedlings during summer months. However, this practice does not permanently solve the problem, as shallow cultivation does not disturb sufficiently the root system while it increases the problem by dispersing rhizome fragments to non-contaminated areas.
Sources
Kotoula-Syka E (2011) Solanum elaeagnifolium, an increasing problem in Greece. In Brunel S, Uludag A, Fernandez-Galiano E, Brundu G (Eds.) Proceedings of the 2nd International Workshop on Invasive Plants in the Mediterranean Type Regions of the World, 2010-08-02/06, Trabzon, Turkey pp. 400-403.