An improved protocol was developed for Agrobacterium rhizogenes-mediated transformation of broccoli. This procedure uses compounds that enhance the virulence of A. rhizogenes and a Brassica campestris feeder cell layer. Leaf explants or intact cotyledons of three broccoli cultivars: Green Beauty, Shogun and Green Belt, were co-cultivated with A. rhizogenes strain A4T harbouring the binary vector pLN35. The T-DNA of this binary vector contains genes encoding antisense 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase (35S-ACC-5'7') and neomycin phosphotransferase II (NOS-NPTII-NOS). Two cultivars were successfully transformed, Shogun and Green Beauty, with a transformation efficiency of 35% and 17%, respectively. Fertile plants were regenerated from kanamycin-resistant hairy roots by transfer to hormone- containing media. Integration of the T-DNA was confirmed by the polymerase chain reaction (PCR) and Southern analyses. Analysis of ethylene production by fully open flowers of three transgenic lines of Shogun demonstrated the feasibility of down-regulating ethylene biosynthesis using an antisense ACC oxidase gene. One transgenic line, Sh/2, showed a 91% reduction in ethylene production after 96 h in comparison to the non-transgenic control.

Item Type:	Refereed Article
Research Division:	Agricultural and Veterinary Sciences
Research Group:	Crop and Pasture Production
Research Field:	Crop and Pasture Improvement (Selection and Breeding)
Objective Division:	Plant Production and Plant Primary Products
Objective Group:	Winter Grains and Oilseeds
Objective Field:	Grain Legumes
UTAS Author:	McNeil, DL (Professor David McNeil)
ID Code:	52471
Year Published:	1999
Web of Science® Times Cited:	21
Deposited By:	Agricultural Science
Deposited On:	2008-07-17
Last Modified:	2011-11-24
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