中文摘要：

按照极性的高低用6种溶剂对鄂尔多斯半日花进行活性物质提取，以生长速率法测定了半日花6种提取物对棉花黄萎病菌V43-1、扩展青霉病菌、梨黑斑病菌和棉花枯萎病菌的抑菌活性．结果表明，不同溶剂提取物的抑菌活性差异很大，其中乙酸乙酯提取物的综合抑菌效果最好，对棉花黄萎病菌V43-1和棉花枯萎病菌的抑制作用高达100％，对梨黑斑病菌最低也达74％；其次，水煮膏的抑菌率也较高，其他几种有机溶剂提取物的抑菌效果明显低于上述两种．不同浓度乙酸乙酯提取物对4种菌的抑菌效果表明，对棉花黄萎病菌V43-1的抑菌效果最好，最低抑菌浓鹰约为5g／L．

英文摘要：

The bioactivitities of 6 kinds of different solvent extracts from Helianthernurn ordosicurn against Fusarium oxysporurn, Verticilliurn dahliae V43-1, Alternaria kikuchiana and Penicilliurn expansurn were studied in laboratory with growth rate method. The results showed that antibacterial activities of different extracts had remarkably significant difference. The ethyl acetate extracts had the strongest fungistasis for all 4 species of fungi, and the highest inhibition rate a- chieved 100 ~ on both Verticilliurn dahliae V43-1 and Fusariurn oxysporurn, while the lowest achieved 74 % on Alternaria kikuchiana. Secondly, the fungistasis of boiling water extracts was merely smaller than ethyl acetate extracts, which was greater than that of other extracts. The antibacterial activities of ethyl acetate extracts with different concentration on Verticilliurn dahliae V43-1 was the best and the MIC was about 5 g/L.