Intercropping sweet corn with summer savory to increase weed suppression and yield

A 2-yr field experiment was conducted to explore the effects on weed growth and crop productivity of intercropping sweet corn with summer savory. Five cropping patterns were set up: sweet corn alone (16 seeds m(-2), in rows, 75 cm apart), summer savory alone (40 seeds m(-2), broadcasted), and three intercropping ratios of 75% sweet corn, 25% summer savory (75%C:25%S), 50%C:50%S, and 25%C:75%S, of plant densities used in respective monocultures. When intercropping, weed biomass decreased as the proportion of summer savory increased, with a reduction of 48%, 61%, and 70 % in 75%C:25%S, 50%C:50%S, and 25%C:75%S, respectively, compared to sweet corn alone. In parallel, sweet corn yield was higher under intercropping compared to its monoculture and increased as the proportion of summer savory decreased, with yield increases compared to corn monoculture of 38%, 32%, and 15% in the first year and 48%, 23%, and 14 % in the second year in 75%C:25%S, 50%C:50%S, and 25%C:75%S, respectively. However, the intercropping pattern had the opposite effect on summer savory yield, with a significant reduction in yield with an increasing ratio of sweet corn. Our results indicate that intercropping sweet corn with summer savory can increase both weed suppression and yield of sweet corn compared to crop monoculture.