AGRONOMIC EVALUATION OF LITTLE KNOWN SPECIES OF Leucaena.

Abstract

The present study was conducted at the Experimental Station of Gualaca in an inceptisol soil of poor fertility, in a completely randomized design with three replications. There were evaluated 16 species of Leucaena considering adaptability, reaction to the presence of Heteropsylla cubana insect, dry matter yield and its quality. The specie L. collinsii subspecie zacapana. The L. esculenta subspecie esculenta and L. lempirana showed poor vigor and yellow leaves, possibly due to the pH of the soil and high content of aluminium. The remain ones showed good vigor and normal green leaves. The species L. leucocephala x L. pallida and L. collinsii subspecie collinsii presented about 25% of defoliation because of insect attack of Heteropsylla cubana; the rest ones were not attacked. The specie L. trichandra prodeced five time more forage (P<0.05) than L. esculenta subspecie esculenta and L. collinsii subspecie collinsii. Crude protein contents (CP) of the species were high and varied (P<0.01) from 18.4% of L. lempirana and L. macrophylla subspecie nelsonii to 24.0% of L. collinsii subspecie collinsii. There were not differences (P<0.05) among in vitro digestibility values of the dry matter (DIVMS), phosphorus (P) and calcium (Ca) of all evaluated species, with respective mean values of 49.18%, 0.17% and 0.58%. These values were low, excepted the one for calcium. It was concluded that the more adaptive species to Gualaca acid soils and showed high dry matter yields, higher than 3000 kg/ha, cut at 60 days, were L trichandra, L. macrophylla subspecie nelsonii, L. leucocephala subspecie Glabrata and L. lanceolata.