Differentiation of adventitious buds from Capsicum annuum L. hypocotyls after co-culture with Agrobacterium tumefaciens

摘要

In vitro organogenesis in hypocotyl explants of the pepper cultivar 'Bryza' was induced on MS medium containing 5 mg/l 6-benzyloaminopurine (BAP) and 1 mg/l indole-3-acetic acid (IAA). The hypocotyl explants were then inoculated with Agrobacterium tumefaciens LBA4404(pBI121). After 2 days of culture the first cell divisions were observed in the epidermis and cortex. After 6-7 days, numerous adventitious bud primordia appeared in 58.4% of the explants. In further stages of culture, buds developed into shoots in 8.4% of the explants. Histological analysis revealed hypertrophy and the presence of necrotic cells in the cortex. Necrotic changes were also observed in the vascular bundles. It is likely that culture on a selective medium containing kanamycin and co-culture with Agrobacterium tumefaciens strongly affected the organization of the hypocotyl meristematic tissue, and in consequence brought about necrosis and isolation of the adventitious buds from the vascular bundles.