Authors: Carlotta Balconi Chiara Lanzanova Elena Conti Tiziana Triulzi Fabio Forlani Marzia Cattaneo Elisabetta Lupotto
Publish Date: 2006/12/05
Volume: 117, Issue: 2, Pages: 129-140
Abstract
The maize gene b32 normally expressed in the maize Zea mays endosperm encodes for a RIP Ribosome Inactivating Protein characterised by antifungal activity Transgenic wheat plants were obtained via biolistic transformation in which the b32 gene is driven by the 35SCaMV promoter in association with the bar gene as a selectable marker Plants were brought to homozygosity through genetic analysis of progeny and pathogenicity tests were performed on the fourth generation Six homozygous b32 wheat lines were characterised All plants had a normal phenotype not distinguishable from the control cv Veery except for slightly smaller size flowered and set seeds Western blot analyses confirmed b32 expression during the plant life cycle in the various tissues Each line differed in the b32 content in leaf protein extracts and the transgenic protein expression level was maintained at least up to 10 days after anthesis Pathogenicity tests for Fusarium head blight FHB were performed on the b32 transgenic wheat lines in comparison to the parental cv Veery Resistance to FHB was evaluated by the single floret injection inoculation method on immature spikes with spores of Fusarium culmorum In all the transgenic lines a similar reduction in FHB symptoms not dependent on the level of b32 protein has been observed 20 and 30 relative to the control respectively 7 and 14 days after inoculation Percentage of tombstone kernels at maturity was also recorded in all transgenic lines disease control for this parameter was around 25 The data obtained indicate that maize b32 was effective as in vivo antifungal protein reducing FHB symptoms in wheat lines expressing the maize RIP protein
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