Black locust (Robinia pseudoacacia L.) resources for degraded area: physiological and biochemical responses to drought

Among the fast growing deciduous trees, black locust (Robinia pseudoacacia L.) is the third after eucalyptus and hybrid poplars to be used in forest stand establishment and artificial reforestations. Black locust is characterized by a dense and highly branched root system, which enables it to succesfully exploit nutrients and water resources of the soil, excellent ability to fix free atmospheric nitrogen, high vitality and seed production. Its rapid spread has been promoted by increasing demands for the afforestation of neglected agricultural lands, by the necessity to fix loose shifting sands and by the possibility to use its wood for tool manifacture, fuel and poles . In several countries it is an economically important tree and as a result Robinia has become a part landscape, nature, culture and economics, including cultural and historical heritage, as it is mentioned in songs, poems, literature and culinary recipes. Despite this, the attempts to list Robinia among the invasive alien species of EU concern a public debate among various interest groups initiated, and individual States depending on the context may take measures against black locust or include it among the invasive alien species. Aim of this study is to cooperate in characterization Robinia pseudoacacia L. trees suitable to reforestation of degraded lands in unfavourable environments. Studies of drought effect on physiological and biochemical adaptation was done comparing two black locust clones that showed different responses to the environmental drought.