氮营养对菘蓝生长及活性成分积累的影响

Effect of Nitrogen Nutrition on Growth and Accumulation of Active Ingredients in Isatis indigotica Fort.

为探讨氮营养对菘蓝生长及活性成分积累动态的影响,采用盆栽试验,在菘蓝营养生长前期和后期分别施用不同次数的氮素组合A[7.5 mmol·L-1的(NH4)2SO4,2.5 mmol·L-1的KNO3,5.0 mmol·L-1的CO(NH2)2]和组合B[2.5 mmol·L-1的(NH4)2SO4、5.0 mmol·L-1的KNO3、10.0 mmol·L-1的CO(NH2)2],分别记作T1~T9,测定了各处理的叶绿素含量、光合参数、生长指标和活性成分含量。结果表明,2个氮素组合施用不同次数后,叶绿素、叶干重与根干重随时间逐渐增加,叶片的净光合速率与叶的靛蓝、靛玉红和根的(R,S)-告依春含量随时间延长的变化规律不明显。在采样后期T3的主根直径、T1的根干重、T7的叶干重、T4的根(R,S)-告依春含量、T2的叶靛蓝含量与T3的叶靛玉红含量为各处理间最大。结合菘蓝根、叶干重及其叶内指标成分靛玉红含量、根内(R,S)-告依春含量,为了获得高产优质的板蓝根药材,建议前期施用1次氮素组合A,后期施1次氮素组合B;为了获得高产优质的大青叶药材,建议菘蓝生长前期施3次氮素组合A,后期施1次氮素组合B。本研究结果为菘蓝合理施用氮肥提供了理论依据。

To study the effect of nitrogen nutrition on the growth and accumulation of active ingredients in Isatis indigotica Fort.,a pot experiment was carried out using two nitrogen combinations by different times. The nitrogen combination A（ 7. 5mmol·L- 1（ NH4）2SO4,2. 5mmol·L- 1KNO3,5. 0mmol·L- 1CO（ NH2）2） was sprayed at the pre-stage and the nitrogen combination B（ 2. 5 mmol·L- 1（ NH4）2SO4,5. 0 mmol·L- 1KNO3,10. 0 mmol·L- 1CO（ NH2）2） was sprayed in the later stage of I. Indigotica by different frequency,marked as T1 to T9. The chlorophyll contents,photosynthetic parameters,growth indexes and the contents of active ingredients treated by different frequency of two nitrogen combinations were determined. The results showed that the leaf chlorophyll relative content（ SPAD）,leaf dry weight and root dry weight gradually increased with the growing time after different applying frequency by two nitrogen combinations. The regular pattern of net photosynthetic rate,the contents of indigo and indirubin in leaves,the content of（ R,S）- epigoitrin in roots with the growing were not obvious. The taproot diameter by T3,roots dry weight by T1,leaves dry weight by T7,（ R,S）- epigoitrin content in roots by T4,indigo content in leaves by T2 and indirubin content in leaves by T3 were the highest in all treatments. In consideration of the dry weights of leaves and roots,indirubin content in leaves and（ R,S）- epigoitrin content in roots,we suggested that the nitrogen combination A should be sprayed 1 time at the pre-stage and nitrogen combination B should be sprayed 1 time in the later stage of I. indigotica in order to gain better Isatidis Radix. The nitrogen combination A should be sprayed 3 times in the pre-stage and combination B should be sprayed 1 time in the later stage of I. indigotica in order to gain better Isatidis Folium. The results of this research provide the theoretical basis for rational application of nitrogen for I. indigotica.