Effects of benomyl and cytokinin on in vitro contamination and growth of Vaccinium arctostaphylos L. node explants

Microbial contamination is one of the main challenges and influential factors in the response of explants under in vitro cultures, especially in woody plants where the explants are prepared from natural habitats. In the present study, to investigate the effects of benomyl on microbial contamination and growth of Vaccinium arctostaphylos L. node explants, MS containing different concentrations of benomyl (0-2000 mg.L-1) was used. Furthermore, to investigate the interaction of benomyl, basal medium, and hormonal composition on the growth response of explants, different basal media (MS, AN, and WPM) containing IBA (0.1 mg.L-1), cytokinin (Zeatin, BAP, and TDZ, each at concentrations of 0, 0.5, 1, and 2 mg.L-1), and benomyl (0 and 150 mg.L-1) were studied. The results showed that benomyl in MS medium had no significant effect on the explants contamination, but use of lower benomyl concentrations (400 mg.L-1 or less) could provide better growth conditions. Interaction of treatments significantly affected the percentage of survival and explants foliation. MS contained benomyl showed higher percentage of survival and foliation than MS without benomyl, but in AN and WPM media, the percentage of survival and foliation were significantly decreased in the presence of benomyl. Furthermore, in AN and WPM media contained cytokinin, the presence of benomyl significantly reduced the foliation percentage, while in MS medium, the effect of benomyl was different depending on the concentration and cytokinin type.