Fertile transgenic corn plants

Abstract

Fertile transgenic Zea mays (corn) plants which stably express heterologous DNA which is heritable are disclosed along with a process for producing said plants. The process comprises the microjectile bombardment of friable embryogenic callus from the plant to be transformed. The process may be applicable to other graminaceous cereal plants which have not proven stably transformable by other techniques.

What is claimed is  
     
         1 . A fertile transgenic  Zea mays  plant containing heterologous DNA which is heritable.  
     
     
         2 . The plant of  claim 1  wherein the heterologous DNA encodes a protein.  
     
     
         3 . The plant of  claim 2  wherein the heterologous DNA is expressed.  
     
     
         4 . The plant of  claim 1  wherein the heterologous DNA encodes an antisense RNA.  
     
     
         5 . The plant of  claim 1  wherein the  Zea mays  plant is selected from the group consisting essentially of field corn, popcorn, sweet corn, flint corn, and dent corn.  
     
     
         6 . The plant of  claim 1  wherein the heterologous DNA comprises a gene selected from the group consisting of non-plant genes, modified genes, synthetic genes, and genes from other plant strains or species.  
     
     
         7 . The plant of  claim 1  wherein said heterologous DNA encodes a beneficial trait to the plant.  
     
     
         8 . The plant of  claim 7  wherein said beneficial trait is selected from the group consisting essentially of promoting increased crop food value, higher yield, reduced production cost, pest resistance, stress tolerance, drought resistance, disease resistance, and the ability to produce a chemical.  
     
     
         9 . The plant of  claim 1  which expresses a selectable marker gene.  
     
     
         10 . The plant of  claim 9  wherein the selectable marker gene confers resistance or tolerance to a compound selected from the group consisting of hygromycin, kanamycin, G418, neomycin, glyphosate, methotrexate, imidazolinone, chlorsulfuron, and bromoxynil.  
     
     
         11 . The plant of  claim 9  wherein the selectable marker gene confers resistance or tolerance to hygromycin.  
     
     
         12 . The plant of  claim 1  which expresses a reporter gene.  
     
     
         13 . The seed produced by the plant of  claim 1  which inherit the heterologous DNA..  
     
     
         14 . The grain produced from the plant of  claim 1  when the heterologous DNA increases the crop food value or feed value of said grain.  
     
     
         15 . The food produced from the grain of  claim 14 .  
     
     
         16 . The R2 and higher generations of the plant of  claim 1 .  
     
     
         17 . The products derived from the  Zea mays  plant of  claim 1  or any part thereof.  
     
     
         18 . The plant of  claim 1  which is produced from transgenic seed produced from a fertile transgenic plant using cross-breeding techniques.  
     
     
         19 . A process for producing a fertile transgenic  Zea mays  plant which stably expresses heterologous DNA which is heritable, wherein the process comprises the steps of (i) establishing a friable embryogenic callus of a plant to be transformed, (ii) transforming said callus by bombarding it with DNA-coated microprojectiles in a microprojectile bombardment procedure, (iii) identifying or selecting a transformed callus cell, and (iv) regenerating a fertile transgenic plant therefrom.  
     
     
         20 . The process of  claim 19  wherein the callus subjected to bombardment is in clumps of about 30 to 80 mg per clump.  
     
     
         21 . The process of  claim 19  wherein the callus had been initiated about 3 to 36 months before the bombardment.  
     
     
         22 . The process of  claim 19  wherein the callus is maintained on solid induction media.