[Impact of priming on seed germination and seedling growth of Oldenlandia diffusa under drought stress].

Current study was carried out to optimize the priming condition of Oldenlandia diffusa seeds, and improve germination rate and seed vigor of 0. diffusa seeds under drought conditions. Uniform design was used to optimize the concentration and priming time of three priming materials (PEG, KNO3, GA3). Different concentrations of polyethylene glycol (PEG) was used to simulate drought stress. The seedling was cultured in 1/4 Hoagland medium for 30 d. The results showed that seed priming treatment with 366 mg x kg(-1) GA3 for 1h resulted in significant increase in germination rate, germination index, vigor, root length, plant height and biomass of O. diffusa seeds under drought stress (15% PEG), while seed priming with 3.0% KNO3 for 1 h showed little effect on germination and growth of O. diffusa seeds under drought stress. Seed priming treatment with appropriate GA3 concentration and priming time could enhance seed germination and drought resistance of O. diffusa in seedling stage.

[Quality classification criteria of Oldenlandia diffusa seeds].

OBJECTIVE: To establish the quality classification criteria of Oldenlandia diffusa seeds. METHOD: Thirty batches of O. diffusa seeds from different provenances with different collecting time were selected. And the seed germination percentage, seed purity, weight per 1 000 grains, moisture content and seed viability were determined and analyzed through SPSS 11.0 software. RESULT AND CONCLUSION: Seed germination percentage was selected as the main index for classification, while seed purity, weight per 1 000 grains and moisture content could be used as references. The quality classification criteria of O. diffusa seeds have been initially established.