Effects of cover crops on weeds density, agronomic characteristics, flower and corm yield of saffron (Crocus sativus L.)

This experiment was conducted in order to study the effect of cover crops on weeds population, flower and corm yield of saffron. The experiment was carried out based on Randomized Complete Block Design with three replications at the Research Station, Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, in 2013-14. The treatments included six cover crops: barely (Hordeum vulgare), persian clover (Trifolium resupinatum), fenugreek (Trigonella Foenum – Graecum L.), grass pea (Lathyrus sativus), rapeseed (Brassica napus) and arugula (Eruca sativa) and control. The results of analysis of variance showed that the effect of cover crops was significant on all of the studied properties. The maximum flower number (23.m-2), flower fresh weight (61.88 kg.ha-1) and stigma dry weight (0.990 kg.ha-1) were observed in the planting of rapeseed. The stigma dry weight at the control treatment was 41% more than planting a different kind of cover crops. Furthermore, the highest total weight of replacement corms and replacement corms weight without tunic per clone were obtained at the control and then planting of rapeseed as a cover crop. The number of replacement corms per clone among cover crop treatments was about 17% more than that of control. However, the lowest amount of all parameters of flower and corm of saffron were obtained for arugula, Fabaceae species and barely cover crop treatments. Meanwhile, the minimum amount of weed density was observed for barely, arugula, Fabaceae species cover crops treatments and control. Therefore, the results indicated that control and rapeseed as a cover crop treatments had better effects on the flower and corm parameters of saffron.