Seed samples were taken from 10 pods. Harvested seed samples were immediately frozen on dry ice and stored at approximately −18◦C until analysis with an HPLC. The endogenous plant hormone analysis was carried out using the HPLC procedure outlined previously (He in et al., 1984; Zhan get al., 1999; Liu et al., 2010). Briefly, samples were initially weighed then about 1 g was homogenized with a Poly tron homogenizer for 3 min in 10 mL of 80% cold methanol (4◦C) containing 10 mg/L BHT(chilled to −80◦C before use). After extraction for 4 h at 4◦C, the homogenates were centrifuged at 10,000 × g for 15 min and then the supernatant was decanted. The residues were further extracted twice with 10 mL of 80% cold methanol and then the combined. These combined extracts were reduced to the aqueous phase in salinized glass tubes under reduced pressure at30◦C. The combined extracts were brought to a volume of 4.0 mL with distilled demonized H2O, and then sonicated, and micro filtered(1.2 m cellulose nitrate, Micro Filtration System)