牡丹皮提取物除草活性初步研究

A preliminary study of the herbicidal activity of the extracts from Cortex Moutan Radicis

为明确牡丹皮(Cortex Moutan Radicis)的除草活性并初步探索其活性成分分离条件,采用平皿法、土壤喷雾法及茎叶喷雾法测定了牡丹皮不同极性溶剂萃取物对反枝苋Amaranthus retroflexus和稗Echinochloa crus-galli的除草活性。平皿法测定结果显示,在1 mg/mL浓度下,牡丹皮正丁醇萃取物的除草活性最强,对反枝苋幼根和幼茎的抑制率分别为67.88%和65.71%,对稗草幼根和幼茎的抑制率分别为68.72%和71.32%;毒力测定结果表明,牡丹皮正丁醇萃取物对反枝苋幼根和幼茎的IC50分别为12.28 mg/L和19.67 mg/L,对稗草幼根和幼茎的IC50分别为43.35 mg/L和72.79 mg/L。土壤喷雾法和茎叶喷雾法测定结果显示,在5 mg/mL浓度下,牡丹皮正丁醇萃取物对反枝苋和稗草的鲜重抑制率最高,其中土壤喷雾法对反枝苋和稗草的鲜重抑制率分别为81.43%和83.18%;茎叶喷雾法对两种杂草的鲜重抑制率分别为80.83%和83.65%。由此可见,牡丹皮的除草活性成分主要集中在正丁醇萃取物中,值得进一步研究。

In order to clarify the herbicidal activity of Cortex Moutan Radicis and preliminarily explore the separation conditions,the herbicidal activities of different extracts from the Cortex Moutan Radicis against Amaranthus retroflexus and Echinochloa crus-galli were determined by bioactivity assay in the laboratory.The plating method showed that the n-butanol extracts of the Cortex Moutan Radicis(1 mg/mL)had the strongest herbicidal activity,with an inhibition rate of 67.88%and 65.71%against young roots and stems of A.retroflexus,and 68.72%and 71.32%against young roots and stems of E.crus-galli,respectively.Further toxicity assays showed that the IC 50 values of n-butanol extracts of Cortex Moutan Radicis were 12.28 mg/L and 19.67 mg/L against young roots and stems of A.retroflexus,43.35 mg/L and 72.79 mg/L against E.crus-galli,respectively.The soil spray method showed that the n-butanol extracts of Cortex Moutan Radicis(5 mg/mL)had the strongest herbicidal activity,with a fresh weight inhibition rate of 81.43%and 83.18%against A.retroflexus and E.crus-galli,respectively.The n-butanol extracts of Cortex Moutan Radicis also had the strongest activity by using the stem-leaf spray method,with a fresh weight inhibition rate of 80.83%and 83.65%against A.retroflexus and E.crus-galli,respectively.It suggested that the herbicidal active components of Cortex Moutan Radicis are mainly concentrated in the n-butanol extracts,and the active compounds are worth further investigation.