Pollen Transformation

• Earliest priority – 15 July 1997
• Filed – 14 July 1998
• Granted – 3 May 2001
• Expected expiry – 14 July 2018

The Australian patent 733 080 claims the same method for transforming pollen of a plant with Agrobacterium as the United States patent. However, the Australian patent claims in addition a specific medium for pollen germination and pollen tube growth.

United States Department of Agriculture (USDA)

• Earliest priority – 15 July 1997
• Filed – 14 July 1998
• Granted – 5 March 2003
• Expected expiry – 14 July 2018

The European patent 996328 claims the same method for transforming pollen of a plant with Agrobacterium as the United States patent.

Designated contracting States at the time of grant are: Austria, Belgium, Switzerland, Cyprus, Germany, Denmark, Spain, Finland, France, United Kingdom, Greece, Ireland, Italy, Liechtenstein, Luxembourg, Monaco, Netherlands, Portugal, Sweden

• Earliest priority – 15 July 1997
• Filed – 15 July 1997
• Granted – 27 July 1999
• Expected expiry – 15 July 2017

Delta and Pine Land Co., acquired exclusive licensing rights to the pollen-transformation system developed by the USDA in the United States. (Source: Ag Biotech InfoNet, January 26, 2001).

The United States patent 5 929 300 claims:

• a method for producing a transgenic plant by transforming pollen of a plant with Agrobacterium carrying a foreign gene and then fertilizing a second plant with the transgenic pollen to obtain transgenic seed. The transgenic plant is obtained by germination of the transgenic seeds. The Agrobacterium must be applied as a lawn to a solid pollen culture medium and the pollen must also be applied to the solid culture medium.  Thus, it appears that other methods of applying the Agrobacterium (e.g., by pipetting drops onto the medium) might not fall within the scope of the claims.

• Earliest priority – 15 July 1997
• Filed – 14 July 1998
• OPI – 28 January 1999

1. National phase entry of WO 1999/03326 in Canada (CA 2296501) is pending.
2. National phse entry of WO 1999/03326 in China (CN 1098029 C) has been published as granted on 8 January 2003.
3. Related patent documents also filed in Brazil (BR 9811791), The Hong Kong Special Administrative Region of the People’s Republic of China (HK 1026118), Taiwan (TW 577922) and South Africa (ZA 9806240).

A) applying Agrobacteria having a foreign gene to a pollen culture on a solid medium;
B) allowing germination and growth of the transgenic pollen on the medium;
C) fertilizing a second plant with the transgenic pollen;
D) obtaining seed; and
E) germinating the seed to obtain a transgenic plant.

A) obtaining pollen from a first plant;
B) applying a lawn of Agrobacteria to a solid pollen culture medium, the Agrobacteria comprising at least one heterologous gene sequence capable of being transferred to a plant cell;
C) applying the pollen to the solid medium;
D) allowing the pollen to germinate and grow on the medium, thereby producing transgenic pollen;
E) applying the transgenic pollen to the stigma of a second plant capable of being fertilized by the pollen of the first plant, thereby fertilizing the second plant;
F) obtaining transgenic seed from the second plant;
G) germinating the transgenic seed to obtain a transgenic plant.

A medium for pollen germination and pollen tube growth comprising agarose, sucrose, KNO₃, MnSO₄ , H₃BO₃, MgSO_4, and gibberellic acid.