Leucaena leucocephala ( Lam. ) De Wit . New genus and new adven titious species naturalized in Paraguay

Abstract

The genus Leucaena, described by George Bentham(J. Bot. Hooker 4: 416-417, 1848), belongs to the family Fabacea, subfamily Mimosoidea. It includes shrubs and trees native to the American continent (specially Mexico and Central America). The specie Leucaena leucocephala (Lam.) de Wit ssp. leucocephalaand ssp. glabrata (Rose) Zarate P. are used extensively in throughout the tropics and subtropics as green manure and forage. Local publications and technical reports about the introduction of the species as a growing economic importance and own observation of the spontaneous growth of the species in various locations of Paraguay merit the official record of this entity as introduced and naturalized specie of the Paraguayan Flora. So, botanical databases ("Flora del Conosur", "Tropics", IPNI), local Herbaria (FCQ) were reviewed and botanical collections and photographic records were made to document the work. It was found collections of specimens of cultivated and spontaneous growth, since 1977, in Asunción Capital, Central, Paraguarí, President Hayes, Boquerón; and it was confirmed the presence and spontaneous growth of the species with its two subspecies. The specimens collected in Cordillera and Canindeyú were identified as ssp. glabrata. Leucaena leucocephala (Lam.) de Wit ssp. leucocephala and ssp. glabrata (Rose) Zarate P. has given clear evidence of being naturalized in Paraguay, that its spontaneous growth was registered. Its invasive behavior in other regions of the earth shows signs of that here may also have it in favorable conditions, what it has been able to register in this work.