The effect of pretreatment of silver nitrate (AgNo۳) on the vitro regeneration of rapeseed (Brassica napus)

Rapeseed is the second important oilseed crop in the world which is also one of the first products that has been genetically manipulated. Given that achieving a method and plant propagation conditions of callus is the first step to a successful transformation program, in this study, effective factors on direct shoot proliferation of rapeseed varieties including RGS۰۰۳, Sarigol, SLM۰۴۶ and Orient in connection with the pretreatment of silver nitrate (in three levels of zero, ۲.۵ and ۵ mg per liter) were studied as a factorial experiment with a completely randomized design in three replications and eight samples in each iteration. After disinfection, seeds were cultured in sodium hypochlorite (in MS environment) in order to generate explants, so that five day old seedlings were used to prepare Cotyledon explants and also eight day old seedlings for Hypocotyls’ explants. Results of variance analysis showed that genotype, explants and applying different pretreatment on callus formation had a significant impact on the regeneration of rapeseeds and its studied traits such as the number of shoots and the percentage of regeneration. While except the interaction of genotype × explants, other interactive effects were not significant on the rapeseed’s response to regeneration. Also, in this experiment, it was determined that cotyledon explants of has much more organogenesis than hypocotyls. Although in both cases the maximum regeneration and shoot proliferation was recorded at the level of ۲.۵ mg per liter of silver nitrate. So, the pretreatment of silver nitrate can be used for the regeneration of oilseed rape, also, it is recommended to examine different levels of the pre-treatment method and different varieties of rapeseed in future studies.

Keywords:

rapeseed , callus formation , explants , silver nitrate.