Study on sugar beet micropropagation and production of photoautothrophic microplants

Sugar beet is an essentially self-sterile plant for which the vegetative propagation is used to obtain identical sister plants. Sugar beet micropropagation is initiated by meristematic cuttings. Sugar beet meristematic flower stalk explants were established in sterile cultures and used for shoot propagation. Two PGoB medium with different hormonal combinations: 1) BA/NAA/IBA at 1, 0.1 and 0.1 and 2) BA/NAA/GA3 at 0.5, 0.1 and 1 mg/l were compared for rate of shoot induction in three genotypes: IR428, IR445 and IR463 at 10 - 20 and 30 days after culture and at the time of transfer for root initiation. Experiment was conducted in a factorial design with time as the main plot, media and genotypes as sub plots, with eight replications each unit consisting of one shoot/culture vessel. Duncan's multiple range test was performed for mean comparison. ANOVA results showed that all factors (time, medium, genotype), had significant effects on micropropagation. More shoots were produced in the second medium as compared to the first. Mean no. of shoots varied among genotypes and increased with days after culture. In the first medium, genotypes were classified in three groups according to their mean no. of shoots but the two best (IR428 and IR463) appeared in one group in the second medium. Paclobutrazol treatment (0.2%) applied on microplants foliage and utilization of a water culture device, designed to support microplants to gain photoautotrophic growth.