Effects of weed management strategies on weed density and biomass and saffron (Crocus sativus) yield

In order to study and compare chemical and non-chemical methods of weed management in saffron (Crocus sativus) fields، two field experiments were carried out in a randomized completely block design with three replications at Research Field Station of Gonabad during 2009 to 2011. Treatments included cover crops of barely، Mushroom bed mulch، herbicides of haloxyfop R methyl ester (EC10%)، iodosulfuron methyl sodium+mesosulfuron. methyl + mefenpyr. diethy (WG6%) l، hand weeding (DF75%) and control. For determining the ability of treatments for weed control، dry matter of weed، leaf dry weight of saffron، stigma and saffron flower yields were determined. Results showed that dominant weed species were mouse barely (Hordeum murinum)، wild barley (Hordeum spontaneum) Hoary cress (Cardaria draba)، and yarrow (Achillea millefolium). Herbicides of iodosulfuron methyl sodium + mesosulfuron methyl + mefen pyr. Diethy (WG6%) destroyed grasses and broadleaf، but it destroyed saffron plant too. Haloxyfop. R methyl ester damaged grasses but decreased stigma yield and leaf of saffron. Applied mulch was not be able to control the weeds، however، it increased saffron stigma yield. Cover crops of barley significantly decreased weed dry matter weights. Barley caused least weeds dry matter weight similar to hand weeding. In conclusion، the treatments of cover crops showed the best performances in weed control and saffron yield comparing to other studied weed management methods.