Rapid and massive production of date palms from a single offshoot is confronted by bacterial contamination during the establishment and subculture of in vitro plant culture. Management methods of the bacterial contamination usually consider the use of certain antibiotics and inorganic materials. However, their extensive use led to the emergence of drug-resistant bacterial strains. In this study, we investigated antibacterial agents included chitosan, silver nitrate (AgNO3), copper (Cu), zinc (Zn), sodium thiosulphate, the nanoparticle formulations (NPs) of chitosan NPs, AgNO3NPs, CuNPs, ZnNPs and combinations of chitosan and each of the latest three, in comparison to the widespread-used antibiotic streptomycin. Rooting subculture medium were supplemented with antibacterial agents with certain concentrations, the percentage of bacterial contamination was recorded, growth parameters of plantlets were assessed, and leaf content of total amino acid was assessed then the regenerated plantlets were acclimatized under greenhouse conditions. Results revealed that the percentage of culture contamination was reduced to 0% with the treatments of chitosan NPs, AgNO3NPs, or any of their combinations at all tested concentrations. As for the growth characteristics of plantlets and the amino acids content, chitosan, AgNO3 or their combination - either in the nano form or in the ordinary form - gave the highest records. Similarly, at the acclimatization stage, the greatest survival percentage was corresponded to the plantlets treated with chitosan, AgNO3 or their combination, either in the nano form or in the ordinary form. These findings provided highly effective alternative antibacterial agents considering the quality and survival rate of regenerated plantlets. |
