IMPROVED BRASSICA NAPUS L., REGENERATION FROM HYPOCOTYLS USING THIDIAZURON AND BENZYLADENINE AS CYTOKININ SOURCES

A reproducible system to produce regenerated Brassica napus L., plants has been developed using hypocotyl explants. Different concentrations of Benzyladenine (1.5, 3.0 and 4.5 mg l -1 ) and Thidiazuron (0, 0.15 and 0.30 mg l -1 ) were evaluated for shoot regeneration using 7, 14 and 21 day old hypocotyl explants. Treatments were arranged in a factorial experiment as a randomized complete block design with three replications. Significant differences were found in the interactions of Benzyladenine and Thidiazuron concentrations as well as the ages of the explants. Maximum shoot regeneration was obtained using 4.5 mg l -1 Benzyladenine and 0.3 mg l -1 Thidiazuron. Shoot regeneration was highly affected by the age of the explants. It was found that 21 day old explants were more likely to undergo shoot development than the others. Under these culture conditions, the highest percentage of shoot regeneration was 174.0% for hypocotyl explants. Regenerated shoots rooted when cultured on a root induction medium supplemented with 2 mg l -1 of Indolebutyric acid. Rooted plantlets were successfully established in the soil which developed normal fertile flowers and viable seeds. In light of its efficiency, this hypocotyl regeneration method could be a suitable tool for genetic transformation using Agrobacterium.