Agrobacterium-mediated transformation of five inbred maize lines with the Brittle 2 gene

Abstract

The Brittle 2 (Bt2) gene encodes a small subunit of ADP-glucose pyrophosphorylase (AGPase) enzyme, one of the enzymes that play an important role in endosperm starch biosynthesis. We carried out a study to transfer the Bt2 gene into several inbred maize lines and regenerate transgenic maize plants possessing the transgene, which can be used to further study the role of the Bt2 gene in starch biosynthesis. Agrobacterium tumefaciens strains C58 and EHA105 harboring the transformation vector pCambia2300/Ubi-Bt2-Nos were used to transfer the Bt2 gene into five inbred maize lines, H14, H26, H240, H95, and N18. Transformed calli were selected on selection medium containing 100 mg/L of kanamycin. The stable integration of the Bt2 gene into transgenic plants was confirmed by Southern hybridizations. We recorded the different transformation frequencies in the experiments with A. tumefaciens strains C58 and EHA105. Transgenic plants were regenerated from transformed calli of all five studied maize lines. Transformation frequencies varied from 1.09% to 2.33%, depending on maize genotypes. The results obtained show that our transformation system is effective for numerous maize genotypes. H95 and H240 are good lines for gene transfer in maize.

The Role of Plant Genotype, Culture Medium andAgrobacteriumon Soybean Plantlets Regeneration during Genetic Transformation

“…Relatively low breeding progress, high self-incompatibility and inbreeding depression may be some of the factors encouraging genotype specificity and recalcitrance in many crops. Evidence of these effects were reported by Gawali et al [54], Targonska et al [55], Nguyen et al [56] and Wang et al [57] in Cajanus cajan, Secale cereale L., Zea mays L. and Triticum aestivum.…”

Overexpression of the IbOr gene from sweet potato (Ipomea batatas ‘Hoang Long’)in maize increases total carotenoid and β-carotene contents

“…Maize transformation and regeneration of transgenic plants were performed as previously described by Nguyen et al (2016): immature embryos at 10-13 days after pollination from the maize lines were used for transformation using Agrobacterium tumefaciens strain C58 harboring the pCambia2300/Glo1/IbOr/Nos construct. The treated embryos were cultured on modified N6 medium (basal N6 medium (Chu et al, 1975) supplemented with 2 mg/L 2,4-D, 10 mg/L AgNO 3 , 2.3 g/L L-proline, 100 mg/L casein hydrolysate, 20 g/L sucrose, 10 g/L glucose, 100 µM acetosyringone, and 7.5 g/L agar; pH 5.8) for cocultivation for 3 days in the dark.…”