1-萘氨甲酰苯甲酸、外源IAA和GA_3对拟南芥根的伸长和向重力性反应的影响

Effects of N-1-naphthylphthalamic Acid and Exogenous IAA and GA_3 on the Elongation and Gravitropic Responses of Arabidopsis Roots

拟南芥幼苗用1-萘氨甲酰苯甲酸（NPA）、IAA和GA3处理后测定根的伸长和向重力性弯曲的结果表明，低浓度（0．001μmol·L^-1）IAA和（0．01—1μmol·L^-1）GA3促进根的伸长和向重力性弯曲，高浓度（0．01-10μmol·L^-1）IAA和（10—100μmol·L^-1）GA3的则相反。NPA在总体上是抑制根的伸长和向重力性弯曲，但低浓度（0．4μmol．L^-1）的NPA有促进根伸长的趋势。低浓度的IAA和GA3均拮抗NPA对根伸长的影响，且低浓度的GA3对根伸长的促进作用并不依赖IAA。

The seedlings of Arabidopsis were treated with N-1-naphthylphthalamic acid （NPA）, IAA and GA3 respectively and also treated with NPA associated with IAA or GA3 respectively. The root length and curvature were measured after the primary root was placed horizontally for a period of time. The results indicated that at low concentrations both IAA （0.001 μmol.L^-1） and GA3 （0.01-1 μmol.L^-1） could facilitate the root elongation and gravitropic curvature and at high concentrations IAA （0.001-10 μmol.L^-1） and GA3 （10-100 μmol.L^-1） could restrain the root elongation and gravitropic curvature, that NPA could exert its inhibitions on the root elongation and gravitropic curvature as a whole, but at low concentrations NPA （0.4 μmol.L^-1） tended to promote the root elongation, that at low concentrations both IAA and GA3 could oppose the prohibitive action of NPA on the root elongation and that the stimulative action of GA3 at low concentrations on the root elongation was independent of IAA.