摘要
以拟南芥的赤霉素 (GA)缺陷型突变体ga 1,ga 2 ,ga 3和GA不敏感型突变体ga i为材料 ,研究了光和 4种GA对拟南芥种子萌发和幼苗生长影响的相互关系。结果表明 :(1)烯效唑对ga i种子萌发的抑制在光下可明显被GA恢复 ,而在黑暗中GA的作用不明显。 (2 )在光下低浓度的外源GA3 可使ga 1,ga 2和ga 3的种子萌发 ,而在黑暗中同样浓度的GA3 则难以使种子萌发。 (3)光可以降低种子萌发所需求的GA的剂量。 (4 )ga i和ga 1的幼苗的呼吸代谢有明显差异。以上结果说明
ga 1, ga 2, ga 3 are gibberellin deficient Arabidopsis mutants, ga i is a gibberellin insensitive mutant. The relationship between the role of gibberellin and light during seed germination and seedlings was investigated. Inhibition of ga i germination by uniconazole and prohexadione was recovered partially by application of GA 3 in light, but not in the dark (Figs.1,2). GA 3 was active inducing ga 1, ga 2 and ga 3 germination in light,but not in the dark (Fig.4). Light lowered GA concentration required for germination from 10 -4 mol/L in the dark to 10 -6 mol/L in light (Fig.3). The respiratory metabolism of ga 1 was different from ga i and wild type (Ler) (Table 1). These results show that light might increased sensitivity of Arabidopsis seed to exogenously applied GA rather than the capacity to synthesize GAs
基金
国家自然科学基金资助项目!(No39870051)
