The effect of maize, sunflower and soybean intercropping at leucaena sowing on the establishment of this species, the recovery of star grass and grain yield of the intercropped seasonal cultures was studied. A random block design with 4 replications was used. Treatments were: leucaena sown alone or intercropped with 1 or 3 furrows between a double row with maize, sunflower or soybean after a conventional soil preparation; At 35 days of sowing the number of plants/m(2) of leucaena was similar in all treatments (5-6 plants/m(2)). In the cultures, this measurement varied according to the species, being greater(P < 0.001) in soybean when 3 furrows between double rows of leucaena were sown. Yield (t/ha DM), height, leaves and stems/leucaena plants were not affected by the intercropped species 120 days after sowing. The best grain yield was obtained when 3 furrows of soybean between double rows of leucaena (0.72 t/ha) were intercropped. Sunflower contributed 1.95 t/ha of DM of harvest residues which differed (P < 0.05) from the remaining treatments. At the end of the experiment, 11 months after sowing, leucaena yield (1.95 t/ha DM) was higher(P < 0.05) when one furrow of sunflower was intercropped and lower (0.64 t/ha) when 3 furrows of sunflower were sown. The highest yield (P < 0.05) of star grass (2.6 t/ha DM) was attained when 1 or 3 furrows of soybean were intercropped and the lowest was when 3 furrows of sunflower were intercropped between double rows of leucaena (1.4 t/ha DM). It was concluded that the contribution to grain production when 3 furrows of maize or soybean are intercropped is an option to decrease the establishment costs of leucaena and star grass. Soybean had a higher contribution to grain production and it favoured or did not affect biomass production of leucaena and star grass. A single row of sunflower also improved leucaena yield.
