Effects of soil conductivity on properties of saffron corms and in vitro production of its style explants

Abstract

Saffron is the dried stigmas of Crocus sativus L., a member of the Iridaceae family which ispropagated by means of corms. Corms are faced with many stresses in soil. Therefore, it isimportant to reduce these stresses and improve the quantity of saffron production. Biotic andabiotic stresses disrupt the metabolic balance of cells; thereby, resulting in accumulation ofreactive oxygen species (ROS) which cause oxidative damage. In this study, the effect of soilelectrical conductivity (EC) on biochemical indicators of corms, the percentages of callusformation and stigma-like structures (SLSs) on calli were investigated. In order to obtain calliand SLSs, immature style explants from floral buds of corms were collected from three regions(Shahroud, Mardabad and Torbat Heydarieh) and used for tissue culture. Style explants wereseparated first from the immature floral buds, then sterilized and used for tissue culture.Biochemical analysis of calli with SLSs including malondialdehyde (MDA) and prolinecontents, antioxidant enzymes activities and polysaccharides and reducing sugars contents wereinvestigated and compared. Moreover, sodium and potassium ions content and EC of soils ofthe three regions were investigated. The results indicated that corms from Shahroud with thehighest level of EC soil showed more imposed stress than that from Torbat Heidariye andMardabad but the calli percentage and number of SLSs of Mardabad’s were higher than those ofthe other two respectively. In this study, a close relationship between soil EC and in vitroproduction of saffron with a short glance on epigenetic modification was postulated.