An experiment was carried out from June to September 2003, in the field, in Mossoró, Rio Grande do Norte State, Brazil. Associations of carrot (cv. Brasília) and lettuce (cv. Tainá) planting densities on carrot agronomic performance in strip-intercropping system were evaluated. The experimental design was of randomized complete blocks in a 4 x 4 factorial scheme with five replications. The treatments of the factorial consisted of the combination of four carrot-planting densities [100%; 80%; 60% and 40% of the recommended sole crop density (RSCD)] with four lettuce-planting densities (100%; 80%; 60% and 40% of the RSCD). The recommended planting density for the sole crop in the region is of 500.000 plants/ha for carrot and 250.000 plants/ha for lettuce. From the carrot crop we evaluated the plant height, shoot and root dry mass, total and commercial yield and classification of roots. No significant interaction between carrot densities and lettuce densities for any assessed trait in carrot crop was obtained. Also, no significant effect of increase in lettuce density was observed for any carrot-assessed trait. Plant height increased as carrot planting density increased, whereas shoot and root dry mass, and percentage of long and mean, and refused roots decreased with increasing of carrot density. As the association of carrot and lettuce planting densities increased, the total and commercial yield and percentage of short roots increased.
Daucus carota; Lactuca sativa; yield; root quality
