Two experiments were carried out from September to May 2002, in Mossoró, Rio Grande do Norte State, Brazil, to evaluate the agrieconomic performance of two lettuce groups under bicropping, sole crop and intercropping system with two carrot cultivars (Alvorada and Brasília) in a strip-intercropping arrangement. The experimental design was of group balanced blocks with four replications. The evaluated lettuce cvs. were from the crispleaf group (Lucy Brown, Tainá, Laurel and Verônica) and looseleaf group (Babá de Verão, Maravilha das Quatro Estações, Elisa and Carolina). In the intercropping experiment, the split-plot scheme was used. In the plots the carrot cvs. were assigned and in the subplots the lettuce cvs. of both groups. From the lettuce cvs. were obtained data of leaf yield and, for the carrot cvs. were obtained total and commercial yield, besides the root classes. Agrieconomic indices such as land equivalent ratio, gross and net income, monetary advantage, rate of return and profit margin were used to measure the efficiency of intercropping systems. No significant interaction was obtained between carrot and lettuce cvs. in yield of both crops. Carrot cvs. did not influence crop yield and lettuce cvs. had no influence on carrot yield. In the bicropping of lettuce with carrot, the cvs. Lucy Brown and Tainá (crispleaf group) and Babá de Verão and Maravilha das Quatro Estações (looseleaf group) had presented the best yield performance in the first planting. In the second planting, only cv. Maravilha das Quatro Estações of looseleaf lettuce group had presented the best performance under intercropping. Lettuce cvs. of crispleaf group intercropped with carrot had presented the best yield performance when compared to those of the looseleaf group. The intercropping systems of carrot 'Alvorada' x lettuce 'Lucy Brown' and carrot 'Brasília' x lettuce 'Maravilha das Quatro Estações' in a strip arrangement of four carrot rows alternated with four lettuce rows resulted in the best agrieconomic indicators, with land equivalent ratios of 2.16 and 2.15, rates of return of 2.05 and 2.33, and profit margins of 53.92% and 59.83%, respectively.
Daucus carota; Lactuca sativa; agrieconomic efficiency
