Onions (Allium spp)

Summary

The New Zealand Institute for Crop & Food Research and Seminis Vegetable Seeds have filed patent applications directed to the transformation of Alliumspp. (onions) using Agrobacterium.

  • The New Zealand Institute for Crop & Food Research: the PCT application contains a very broad independent claim reciting a method of transforming plants of the Allium genus but lacks recitation of any steps. As such, it is highly unlikely to be granted as filed. If allowed, such a claim would cover any method used to this end. It is possible that converted patents will not contain such a claim. New Zealand application NZ 513184, for example, specifies the target tissue for transformation (embryos or embryo-derived cell cultures), and that transformation is carried out without passage through a callus stage. A preferred explant used in the transformation procedure with Agrobacterium are wounded immature embryos.
  • Seminis Vegetable Seeds discloses a method that uses embryogenic callus, embryos or flower buds as a target explant for transformation with Agrobacterium.

Because of their limited subject matter, these applications may be affected by other patents with granted claims to general transformation methods for monocots.

Specific Patent Onions – Specific Patent Information

Patent Number Title, Independent Claims and Summary of Claims Assignee
WO 2000/44919 A1

  • Earliest priority – 29 January 1999
  • Filed – 10 December 1999
  • OPI – 3 August 2000
Title – Transformation and Regeneration of Allium plants
A preferred embodiment utilizes the alliinase gene, which encodes an enzyme involved in sulfur metabolism.

Claim 1A method of transforming plants of the Allium genus.
Claim 3A method of transforming plants of the Allium genus comprising inoculating an embryo culture of an Allium species with anAgrobacterium tumefaciens strain containing a suitable vector or plasmid.
Claim 9A method of transforming Allium using immature embryos as an explant source, including:
(a) isolating immature embryos of the Allium plant to be transformed;
(b) innoculating cultures of the immature embryos with an Agrobacterium tumefaciens strain containing a binary vector;
(c) wounding embryos and infiltrating embryos with agrobacteria;
(d) transferring embryos to a selective medium;
(e) culturing embryo pieces;
(f) selecting putative transgenic cultures; and
(g) regenerating plants.

New Zealand Institute for Crop & Food Research Ltd.

AU 763531 C

  • Earliest priority – 29 January 1999
  • Filed – 10 December 1999
  • Granted – 24 July 2003
  • Amended – 26 February 2004
  • Expected expiry – 9 December 2019
Title – Transformation and regeneration of Allium plants

Claim 1A method of transforming plants of the Allium genus comprising the following steps:
(a) delivering previously manipulated DNA into embryo, or embryo derived culture cell types of the Allium genus via vector or direct gene transfer;
(b) selecting transformed plant material;
(c) culturing and regenerating the transformed plants;
wherein the transformation is carried out without passage through a callus phase.
Claim 7A method of transforming Allium using immature embryos as an explant source, including:
(a) isolating immature embryos of the Allium plant to be transformed;
(b) innoculating cultures of the immature embryos with an Agrobacterium tumefaciens strain containing a binary vector;
(c) wounding embryos and infiltrating embryos with agrobacteria;
(d) transferring embryos to a selective medium;
(e) culturing embryo pieces;
(f) selecting putative transgenic cultures; and
(g) regenerating plants.
Remarks
  1. Related patent granted in New Zealand (NZ 513184).
  2. National phase entries of WO 2000/44919 in Canada (CA 2361143 A1) and Europe (EP 1144664 A1) are still pending.
EP 1180927 B1

  • Earliest priority – 5 May 1999
  • Filed – 5 May 2000
  • Granted – 21 December 2005
  • Expected expiry – 4 May 2020
Title – Transformation of Allium sp with Agrobacterium using embrogenic callus cultures

A method of transforming Allium species (onions) with Agrobacterium carrying a heterologous gene. A preferred embodiment utilizes immature embryos and flower buds as target tissue for transformation.

Claim 1A method for transforming an Allium species with a heterologous gene, the method comprising the step of: contacting embryogenic callus material from an Allium species with a bacterium belonging to the genus Agrobacterium which contains a heterologous gene.
Claim 8A method for transforming an Allium species with a heterologous gene, the method comprising the steps of:
a. culturing immature embryos or flower buds from an Allium species on an initiation medium for a period of from about 2 to about 6 months until embryogenic callus material forms on the embryos or flower buds;
b. transferring the embryogenic callus material to a coculture medium and contacting the embryogenic callus material with a suspension of Agrobacterium rhizogenes or Agrobacterium tumefaciens containing a heterologous gene;
c. incubating the embryogenic callus material with the Agrobacterium rhizogenes or Agrobacterium tumefaciens for a period of from about 2 to about 4 days; and
d. removing the Agrobacterium rhizogenes or Agrobacterium tumefaciens from the transformed embryogenic callus material.

Designated contracting State at the time of grant is Spain.

Seminis Vegetable Seeds Inc. (US)

EP 1180927 A1

  • Earliest priority – 5 May 1999
  • Filed – 5 May 2000
  • Granted as EP 1180927 B1 (see above)
Title – Transformation of Allium sp with Agrobacterium using embrogenic callus cultures

A method of transforming Allium species (onions) with Agrobacterium carrying a heterologous gene. A preferred embodiment utilizes immature embryos and flower buds as target tissue for transformation.

Claim 1 (granted)A method for transforming an Allium species with a heterologous gene, the method comprising the step of: contacting embryogenic callus material from an Allium species with a bacterium belonging to the genus Agrobacterium which contains a heterologous gene.
Claim 9 (granted)
A method for transforming an Allium species with a heterologous gene, the method comprising the steps of:a. culturing immature embryos or flower buds from an Allium species on an initiation medium for a period of from about 2 to about 6 months until embryogenic callus material forms on the embryos or flower buds;
b. transferring the embryogenic callus material to a coculture medium and contacting the embryogenic callus material with a suspension of Agrobacterium rhizogenes or Agrobacterium tumefaciens containing a heterologous gene;
c. incubating the embryogenic callus material with the Agrobacterium rhizogenes or Agrobacterium tumefaciens for a period of from about 2 to about 4 days; and
d. removing the Agrobacterium rhizogenes or Agrobacterium tumefaciens from the transformed embryogenic callus material.
AU 780954 B2

  • Earliest priority – 5 May 1999
  • Filed – 5 May 2000
  • Granted – 28 April 2005
  • Expected expiry – 4 May 2020
Title – Transformation of Allium sp. with Agrobacterium using embryogenic callus cultures

Claims of this patent are limited to transforming Allium cepa and A. fistulosum using Agrobacterium.

Claim 1A method for transforming an Allium cepa or Allium fistulosum with a DNA of interest from a heterologous gene, the method comprising the steps of: contacting embryogenic callus material from an Allium cepa or Allium fistulosum with a bacterium belonging to the genus Agrobacterium which contains a DNA of interest from a heterologous gene and obtaining a transformed Allium cepa or Allium fistulosumembryogenic callus under selective conditions.
Claim 8A method for transforming a plant or plant tissue of an Allium cepa or Allium fistulosum with a DNA of interest from a heterologous gene, the method comprising the steps of:
a. culturing immature embryos or flower buds from an Allium cepa or Allium fistulosum on an initiation medium for a period of from about 2 to about 6 months until an embryogenic callus forms on the embryos or flower buds;
b. transferring the embryogenic callus to a coculture medium and contacting the embryogenic callus with a suspension of Agrobacterium rhizogenes or Agrobacterium tumefaciens containing a DNA of interest from a heterologous gene; and
c. obtaining a transformed Allium cepa or Allium fistulosum embryogenic callus under selective conditions.

Note: Patent information on this page was last updated on 7 February 2006.