The total RNA was extracted from the Young Panicle of F1 hybrid rice by Trizol reagent.The mRNA was purified from the total RNA by Poly-A Tract mRNA Isolation Kit and the double-stranded（ds） cDNA was synthesized after reverse transcription.The fragments longer than 400 bp in length were fractionated by Sephrose CL-2B Column

and then ligated into the pTRG vertor.The ligation product was transformed into XL1-Blue MRF Kan Library Pack Competent Cells to construct the bacterial two-hybrid system library.Analysis showed that the primary library contained 1.03×106 pfu/mL

and approximately 100% of the clones were positive recombinants and about 97% of the cDNA fragments inserted were longer than 800 bp in length.The capacity of the amplified library was 1.05×1010 pfu/mL.