THE PLANT CELL, Vol 4, Issue 1 7-16, Copyright © 1992 by American Society of Plant Biologists
Competence of Immature Maize Embryos for Agrobacterium-Mediated Gene Transfer
M. Schlappi and B. Hohn
Friedrich Miescher-Institut, CH-4002 Basel, Switzerland
Agrobacterium-mediated transfer of viral sequences to plant cells
(agroinfection) was applied to study the susceptibility of immature maize
embryos to the pathogen. The shoot apical meristem of immature embryos 10
to 20 days after pollination from four different maize genotypes was
investigated for competence for agroinfection. There was a direct
correlation between different morphological stages of the unwounded
immature embryos and their competence for agroinfection. Agroinfection
frequency was highest in the embryogenic line A188. All developmental
stages tested showed Agrobacterium virulence gene-inducing activity,
whereas bacteriocidal substances were produced at stages of the immature
embryos competent for agroinfection. The results suggested that
Agrobacterium may require differentiated tissue in the maize shoot apical
meristem before wounding for successful T-DNA transfer. This requirement
for the young maize embryo has implications for the possible use of
Agrobacterium for maize transformation.
