عنوان مقاله [English]
Background and Objectives
Crocus flower which is belongs to Iridaceae, is one of the most important ornamental bulbous plants. The propagation of Crocus vernus L. by corm commercially is not affordable due to transmission of fungal and bacterial diseases as well as long dormancy period from 4 to 5 months. So, in vitro culture of Crocus vernus is suitable solution to commercial reproduction. Plant tissue culture technique would be a better alternative for improving quality and production. In order to micropropagation of ornamental saffron, the effect of different culture media on direct organogenesis experiment was conducted in factorial arrangement in a completely randomized design with 3 replications in tissue culture lab., Dep. of hort., Khuzestan Agricultural Sciences and Natural recourses University, during 2015 to 2016.
Material and Methods
The explants used in this experiment were lateral and terminal buds which were evaluated in 10 hormonic treatments and control in the Murashige and Skoog medium. To eliminate surface contamination, the explants were immersed under water for 30 minutes after placing the corms, and then, by preparing a Benlate fungicide solution at high temperature (55 ° C) on a hot plate for 30 minutes, and then 70% ethanol (ethyl alcohol) for 30 seconds and 15% Sodium hypochlorite solution for 6 minutes and then three times washing with sterile distilled water under an airflow bench. The effects of plant growth regulators including of BAP (0.5, 1.0, 2.0 mg/l) TDZ (0.5, 0.75, 1.0) Kin (0.5, 1.0, 2.0 mg/l) along with 0.1 IBA in direct regeneration was investigated.
Results showed kind of plant growth regulators (PGR) and explant type is so important in regeneration of Crocus vernus and without PGR we cannot earn any shoots. In direct organogenesis experiment, the maximum number of multiple shoots (15.84) was obtained from apical bud explant in MS medium supplemented along with 0.5 mg/l TDZ along with 0.5 mg/l BAP and 0.5 mg/l KIN and 0.1 mg/l IBA after 10 weeks, that had a significant difference with other treatments at 1% Duncan test.
In the present study, it was found that 0.5 mg/l TDZ, 0.5 mg/l BAP and 0.5 mg/l Kin along with 0.1 mg/l IBA had the greatest effect on the shoots length, Number of shoots and Percentage of regeneration. We observed 2.0 mg/l BAP along with 0.1 mg/l IBA had the greatest effect on the Number of corm. Furthermore, the results showed the shoot regeneration is controlled by the ratio of cytokinin with auxin. It must be said cytokinins play a role in the synthesis of RNA, stimulation of the production of protein and the activity of some enzymes. Present results said that the use of auxin along with cytokinin has a beneficial effect on shoot regeneration.