Claim 1 A method for screening for overexpression of a transcription factor polynucleotide in plants, said method comprising (a) providing a first pool of donor vectors, wherein each donor vector member comprises a LexA DNA binding domain fused to a GAL4 transcription activation domain, and a second pool of receptor vectors, wherein each receptor vector member comprises a LexA DNA binding site operably linked to a transcription factor polynucleotide; (b) transforming a first plant with a member of said donor vector pool; (c) transforming a second plant with a member of said receptor vector pool; (d) crossing said first and second transformed plants to generate a hybrid plant, wherein the hybrid plant comprises the member of said donor vector pool and the member of said receptor vector pool; and (e) characterizing the phenotype of said hybrid plant so as to identify a hybrid plant overexpressing the transcription factor polynucleotide.
Claim 8 A method for breeding a plant with enhanced tolerance to environmental stress, said method comprising the steps of (a) providing a first transformed plant, wherein said first transformed plant is transformed with a donor vector comprising a LexA DNA binding domain fused to a GAL4 transcription activation domain; (b) providing a second transformed plant, wherein said second transformed plant is transformed with a receptor vector comprising a LexA DNA binding site operably linked to a polynucleotide encoding a transcription factor that confers enhanced tolerance to environmental stress when overexpressed; (c) crossing said first and second transformed plants to generate a hybrid plant, wherein the hybrid plant comprises the donor vector and the receptor vector; and (d) selecting a hybrid plant that overexpresses the transcription factor, wherein the selected hybrid plant has enhanced tolerance to environmental stress.
Claim 16 A method for increasing expression of a transcription factor polynucleotide in a plant, said method comprising (a) providing a first pool of donor vectors, wherein each donor vector member comprises a LexA DNA binding domain fused to a GAL4 transcription activation domain, and a second pool of receptor vectors, wherein each receptor vector member comprises a LexA DNA binding site operably linked to a transcription factor polynucleotide; (b) transforming a first plant with a member of said donor pool; (c) transforming a second plant with a member of said receptor pool; and (d) crossing first and second transformed plants to generate a hybrid plant with increased expression of a transcription factor polynucleotide.
