Squash (Cucurbita pepo)

Summary

The United States patent granted to Asgrow Seeds refers to

  • a method for transforming squash embryogenic calli with Agrobacterium,
  • regeneration of transformed squash plants, and
  • components of an induction medium for regeneration of the transformed calli.

Asgrow Seeds was previously a subsidiary of the Upjohn Company, which was sold to Empresas La Moderna (ELM; Mexico) in 1994, and soon after became Seminis Inc.. Seminis is now owned by Monsanto Co. (acquisition signed in 2005).

Specific Patent Information

Patent Number Title, Independent Claims and Summary of Claims Assignee
US 5677157

  • Earliest priority – 20 September 1989
  • Filed – 5 December 1994
  • Granted – 14 October 1997
  • Expired – 16 November 2005
Title – Somatic embryogenesis and transformation of squash

Claim 1

A method of transforming and regenerating squash plants, which comprises:

A) excising shoot tips from germinating squash;
B) transforming embryogenic calli by inoculating the excised squash tissue with Agrobacterium comprising a DNA construct having a beneficial gene and a plant expressible selection marker gene and culturing the resulting explant on an induction media comprising MS media, 2,4,5-T, BAP, and Kn;
C) selectively growing the transformed embryogenic calli on media containing a selection agent for the plant expressible selection marker gene; and
D) subjecting the transformed embryogenic calli to an embryogenic regeneration procedure from which whole transformed squash plants can be obtained.

Claim 4

A method of transforming and regenerating squash plants, which comprises:

A) excising tissue from mature squash seeds;
B) transforming embryogenic calli by inoculating said excised squash tissue with Agrobacterium comprising a DNA construct having a beneficial gene and a plant expressible selection marker gene and culturing on an induction media comprising MS media, 2,4-D or 2,4,5-T, BAP, and Kn;
C) selectively growing the transformed embryogenic calli on media containing a selection agent for the plant expressible selection marker gene; and
D) subjecting the transformed embryogenic calli to an embryogenic regeneration procedure from which whole transformed squash plants can be obtained.

Granted US 5677157 has expired due to non-payment of maintenance fees.

Methods to transform embryogenic calli derived from squash shoot tips and squash seeds with Agrobacterium having a gene of interest. Media for culturing the transformed explant and embryogenic regeneration procedure are claimed.

Additionally, transformation of the same explants by microprojectile bombardment is also claimed. The claims referring to this transformation method are not shown here.

Asgrow Seed Company

WO 1991/04332 A1

  • Earliest priority – 20 September 1989
  • Filed – 22 August 1990
  • OPI – 4 April 1991
Title – Somatic embryogenesis of squash

Claim 1

A method of regenerating and transforming Cucurbita pepo L. (squash) plants, which belong to the family Cucurbitaceae, which comprises

(1) excising squash tissue selected from the group consisting of shoot tips from germinating squash seeds and squash tissue from mature seeds,
(3) producing embryogenic calli from said tissues, being either non-transformed or transformed,
(4) selectively growing the transformed embryogenic call on media containing kanamycin, and
(5) subjecting the transformed embryogenic calli to an embryogenic regeneration procedure from which whole transformed squash plants can be obtained.

PCT application WO 1991/04332 recites a transformation and regeneration method of Cucurbita pepo. Note that the steps in the published document have skipped number 2. Agrobacterium-mediated transformation of C. pepo is recited in dependent claim 7.

The Upjohn Company
Remarks
  1. National phase entry of WO 1991/04332 in Australia (AU 62840/90) has lapsed on 11 June 1992.
  2. National phase entry of WO 1991/04332 in Europe (EP 62840) has been granted on 30 November 1994. Independent claim 1 does not limit the method of transformation to that of Agrobacterium.
  3. National phase entry of WO 1991/04332 in Japan (JP H 05/500308) has been deemed to be withdrawn on 25 November 1997.

Note: Patent information on this page was last updated on 27 March 2006.