A study of intercropping of maize with sweet basil and borage

Intercropping is one of the environmental friendly ways to improve the use of resources and weed control. A field experiment was performed on maize intercropped with sweet basil and borage under weed free and infestation conditions. The experimental design was a factorial based on randomized complete block design with three replicates. Factors included weed infestation levels (weed free and weed infestated) and intercropping ratios (100:0, 75:25, 50:50, 25: 75, and 0:100, maize: sweet basil or borage). The intercroppping treatments decreased weeds biomass compared to the monocultures of borage and sweet basil. The weeds biomass and density in maize monoculture was lower than the monocultures of the other two plants. Under sole crop condition, the plants yield was higher than intercropping treatments. Weed interference decreased the yield of plants, while this decrease was less in intercropping treatments. Area-time equivalent ratio value showed that the ratios of 50:50 maize: sweet basil, maize: borage and 25:75 maize: borage provided the yield advantages of 11%, 11% and 36% under weed infestation, respectively. Also, area-time equivalent ratio values were higher in weed infestation compared to weed free treatments. The leaves essential oil of sweet basil under intercropping treatments, especially in weedy condition, was further than monocropping treatments. Intercropping of maize with sweet basil was more successful than intercropping with borage in reducing weeds biomass and density. In general, the intercropping of maize with sweet basil was more efficient compared to intercroppping with borage