| A novel alteration in secondary metabolism of maize transformed with wheat oxalate oxidase gene (OXO) was determined using HPLC and microscopy. Phenolic concentration was significantly increased, but DIMBOA synthesis was down-regulated. The high levels of soluble phenolic acids, in particular free ferulic acid, most likely contributed to the insect resistance in the OXO maize.{09}To facilitate future cowpea transformation with the OXO, a stable in vitro regeneration system was established in blackeye cowpea via shoot organogenesis. The optimal initiation medium comprised MS salts, B 5 vitamins, 2 mg 1-1 BAP, 3% sucrose and 0.8% agar at pH 5.8. The highest initiation frequency and shoot number were obtained from the shoot apices of 3-5 days old seedlings. For shoot elongation, 0.5-5.0 mg 1-1 GA3 was required. Rooting medium was MS salts supplemented with B5 vitamins, 3% sucrose and 0.8% agar. |
