Impact of ACCase Inhibitor Herbicides on Saffron (Crocus sativus L.) Yield

Abstract

Saffron (Crocus sativus L.) is a weak competitor against weeds due to its leaf structure and low leaf area index. Therefore, weed control in an important practice to improve it flowering capacity [1]. In this regard a field experiment was carried out at the research field of university of Birjand to investigate the effect of different weed control methods on saffron reproductive growth parameters. The experiment was performed based on a randomized complete block design, during 2019. Corm planting (using corms with ~ 6g weight, density of 50 corms per m2 and planting depth of 20 cm) was done in September 2016, then when the field was two-year old (February 2018) experimental treatments (Table 1) were applied. At the start of the next flowering season (November 2019) saffron flowers were harvested and counted daily. Then mean flower weight and length were determined. In addition, stigmas and petals were dried at shade (~25 oC) for a week and then their yields were measured. All weeds control treatments especially mechanical method (by hand) improved significantly stigma and petal yields. The best concentrations of Sethoxydim and Cletodim were 4.5 and l L ha-1, respectively (Table 1). According to photodegradation and biodegradation of Sethoxydim and Cletodim in environment, it seems that this herbicide have potential to be used in saffron fields [2]. Overall, hand weeding was the best method of weed control in saffron field, but all concentrations of both used herbicides were also useful. However, it is recommended to evaluate these herbicides at the low levels prior to their widespread application in the fields.