Effect of Hairy Vetch (Vicia villosa Roth) on Weeds Control and Production of Coriander (Coriandrum sativum L.) in Itercropping

Evaluation of hairy vetch (Vicia villosa Roth) effect on weed control, yield, yield components and essential oil of coriander (Coriandrum sativum L.) in mixed cropping were important objectives of this study.  

Experiment was carried out as a split plot based on randomized complete block design (RCBD) with 3 replications at the field of Agricultural and Natural Resources Research of Meshginehshahr in 2018. The effect of weed control as the main factor was included two levels of control and non-control of weeds and different planting pattern in 7 level: coriander sole cropping, hairy vetch sole cropping, intercropping of coriander and hairy vetch (1:1) with different spacing of plants on hairy vetch rows including 5 (A), 7.5 (B), 10 (C), 12.5 (D) and 15 (E) cm, were as sub factor.  

The highest number of lateral branches and essential oil percentage (0.29%) of coriander were obtained in E, number of umbrella per plant in all intercropping treatments, and the number of grains per umbrella in C and D treatments. The highest biological yield (3013 kg.ha-1) and grain yield (689.2 kg.ha-1) of coriander were obtained in sole cropping with weed control treatment, and the highest essential oil yields were obtained in sole cropping (1.85 kg.ha-1) and intercropping of coriander with hairy vetch at 15 cm distances on rows (1.86 kg.ha-1) in weed control conditions. The lowest weed biomass was recorded in intercropping with 5 cm distances of seeds on rows of hairy vetch without any differences with 7.5 and 10 cm distances of seeds, which led to decreases of weed biomass by 14.2 and 9.2 % compared to sole cropping of coriander and hairy vetch, respectively. Land equivalent ratio (LER) based on biological yield in all intercropping treatments was greater than 1 and indicated the superiority of intercropping over sole cropping in both crops in the studied treatments.  

In general, to achieve higher yield of coriander essential oil in intercroping with hairy vetch, planting distance of 15 cm of hairy vetch under weed control and planting distance of 5 cm of hairy vetch without weed control are appropriate. For more control on weed, planting of hairy vetch at distances of 5, 7.5 and 10 cm will be effective in intercroping with coriander.