以板蓝根品种安徽亳州种为试材，研究了不同浓度(200、400 mg/L)ALA对板蓝根幼苗光合特性和叶绿素荧光参数的影响。结果表明，与喷蒸馏水相比，板蓝根幼苗叶片的净光合速率(Pn)，气孔导度(Gs)，蒸腾速率(Tr)、胞间CO₂浓度(Ci)显著提高，略提高了板蓝根水分利用率。200、400 mg/L ALA处理后，初始荧光(Fo)极显著(P ＜ 0.01)降低，降低幅度分别为7.6%、14.7%；与喷蒸馏水相比，200 mg/L外源ALA处理最大荧光(Fm)、可变荧光(Fv)、最大光化学效率(Fv/Fm)、潜在光化学效率(Fv/Fo)、光能获取能力(1/Fo-1/Fm)分别提高1.06%、2.98%、1.97%、11.44%，10.98%；400 mg/L外源ALA处理分别提高1.72%，5.54%、3.81%、23.72%，23.53%，除(1/Fo-1/Fm)处理之间差异显著(P ＜ 0.05)外，其余指标处理间差异均达极显著(P ＜ 0.01)水平。喷施ALA能提高板蓝根幼苗植株的光合能力。

Radix isatidis Anhui bozhou was used as the material， the effect of Exogenous ALA on Photosynthesis and chlorophyII fluorescence dynamics of radix isatidis(Isatis indigotica F.) seedlings was studied. The results showed that the net photosynthetic rate(Pn)， stomatal conductance(GS)， transpiration rate(Tr) and intercellular CO₂ concentration(Ci) of seedling leaves of Radix isatidis were significantly increased compared with that of spraying distilled water， which slightly improved the water use efficiency of Radix isatidis. The initial fluorescence (Fo) was significantly decreased (P < 0.05) by 7.6% and 14.7% After 200 mg/L and 400 mg/L ALA treatment. The maximum fluorescence(Fm)， the variable fluorescence(Fv.)， the PS Ⅱmaximum photochemical efficiency(Fv/Fm)， the potential photochemical efficiency(Fv/Fo) and the ability of PS Ⅱ reaction center to trap energy from antenna pigment(1/Fo-1/Fm) were increased by 1.06%， 2.98%， 1.97%， 11.44% and 10.98%， respectively， compared with spraying distilled water with 200 mg/L exogenic ALA；400 mg/L exogenous ALA treatment increased by 1.72%， 5.54%， 3.81%， 23.72%， 23.53%， respectively. There were significant differences among(1/Fo-1/Fm) treatments(P < 0.05)， and the differences among other indexes were extremely significant(P < 0.01)， which indicated that exogenous ALA treatment could improve photosynthesis ability of radix isatidis seedlings.

S567.2

甘肃省中药材产业科技攻关项目(GYC14-04)。