Covering the period of autumn-winter-spring of 2007, a study was performed in Seropédica, Metropolitan Region of Rio de Janeiro State, Brazil, to evaluate different intercroppings between cowpea (cv. Mauá) and corn (cv. AG-1051) under organic farming system. The experiment was carried out in an area of ultisol employing a randomized block design with four replicates. Treatments consisted of four intervals of cowpea sowing, as follows: (E1) 21 days prior to corn; (E2) 14 days prior to corn; (E3) 7 days prior to corn; and (E4) cowpea and corn sowed on the same day. Sole crops of cowpea and corn were included, both sown along with treatment E4. Intercropping with cowpea did not affect corn yield as immature (green) spikes and also had no influence in terms of the spikes basal diameter and length, regardless the intervals between sowing dates. As for cowpea, the sole crop productivity in green beans was superior to its intercropping with corn. The data obtained for the Area Equivalency Index (AEI), higher than 1.0 in all cases, indicated that intercrops were efficient in agronomic/biological terms. Considering, in addition, the yield of each component crop intercropping, cowpea sowing 21 days preceding corn was most adequate to the organic management adopted under regional conditions.
Vigna unguiculata; Zea mays; Area Equivalency Index; agroecology
