Soybean - Patent assigned to University of Mississipppi

A method of regenerating soybeans (G. max) via organogenesis, comprising:

A) obtaining hypocotyl explants from germinated seedlings of soybean plants whose regeneration is desired,
B) maintaining said hypocotyl explants on a shoot induction medium comprising a cytokinin until shoots form at the acropetal end of said hypocotyl explant,
C) excising shoots from said hypocotyl explant and maintaining said shoots on a shoot elongation medium until said shoots are competent on a rooting medium, and maintaining said shoots on a rooting medium until rooted plantlets are formed, and
D) transplanting said plantlets to soil.

A method for transforming soybean plants to express exogenous DNA, comprising:

A) obtaining a hypocotyl explant from germinated seedlings of a soybean plant,
B) maintaining said explant on a shoot induction medium comprising a cytokinin for 16-32 hours,
C) bombarding said explant, with the acropetal end facing up, with microparticles of an inert metal coated with exogenous DNA comprising a plasmid which comprises an expression gene, said expression gene encoding the expression of a protein exogenous to said soybean plant,
D) maintaining said bombarded hypocotyl explant on a medium selective for growth of transformed tissues, followed by maintenance on a shoot elongation medium and preparing plantlets from shoots so obtained.

A method of transforming soybeans, comprising:

A) obtaining a hypocotyl soybean explant from germinated seedlings, and
B) maintaining on its side or upright on a shoot induction medium comprising a cytokinin with a basipetal end thereof submerged in said medium,
C) pre-culturing and/or co-culturing an Agrobacterium strain with a virulence enhancing substance, and
D) adding said pre- or co-cultured bacteria to the acropetal end of said upright hypocotyl explant or by complete submersion,
E) co-incubating said hypocotyl explant for a time sufficient to permit transfection of said hypocotyl explant by said bacteria,
F) disinfecting said hypocotyl explant, maintaining said hypocotyl explant on a shoot induction medium and assaying said explant for expression of introduced foreign DNA, and regenerating hypocotyl explants positive for expression of said DNA.