›› 2006, Vol. 49 ›› Issue (4): 556-561.doi:

• 研究论文 • 上一篇    下一篇

斑点野生稻拒食活性组分的分离及其对斜纹夜蛾消化酶活性的影响

冯国忠,万树青*,潘大建   

  1. 华南农业大学昆虫毒理研究室, 广州 510642
  • 出版日期:2006-09-28 发布日期:2006-08-20
  • 通讯作者: 万树青

Isolation of antifeeding components from wild rice Oryza punctata and their effect on digestive enzymes of Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae)

FENG Guo-Zhong, WAN Shu-Qing, PAN Da-Jian   

  1. Laboratory of Insect Toxicology, South China Agricultural University, Guangzhou 510642, China
  • Online:2006-09-28 Published:2006-08-20
  • Contact: WAN Shu-Qing

摘要: 为了进一步评估斑点野生稻Oryza punctata的抗虫性,采用液液分配萃取和硅胶柱层析的方法,从斑点野生稻甲醇提取物中分离获得石油醚、氯仿、乙酸乙酯、正丁醇和水的萃取物,测定了其对斜纹夜蛾Spodoptera litura 3龄幼虫拒食活性。结果显示,氯仿萃取物比其他4种萃取物具有更高的拒食活性,在25 mg/mL的浓度下,24 h和48 h的拒食率分别为55.62%和52.66%。氯仿萃取物经硅胶柱层析后,得到14个组分。比较14个组分的拒食活性,发现组分4和10为主要的活性组分。这两个组分对斜纹夜蛾幼虫中肠脂肪酶和α-淀粉酶的活性都具有一定的抑制活性,其中组分10对脂肪酶具有显著的抑制效果,以1 mg/mL的浓度活体处理48 h和72 h抑制率分别达19.82%和34.60%; 对α-淀粉酶的影响在48 h和72 h内都具有显著的抑制效果,随着处理时间的延长,其抑制率逐步提高,72 h的抑制率分别为25.06%和27.40%。结果提示斜纹夜蛾幼虫中肠脂肪酶和α-淀粉酶可能是斑点野生稻拒食活性成分的作用靶标。

关键词: 斑点野生稻; 斜纹夜蛾; 拒食活性成分; 脂肪酶; &alpha, -淀粉酶

Abstract: For evaluating the insect resistance property of a wild rice Oryza punctata, five extracts of the wild rice plants with petroleum ether, chloroform, ethyl acetate, n-butanol and water were tested for their antifeedant activity against Spodoptera litura larvae. The results showed that chloroform extract was the most effective one among the five extracts. In 24 h and 48 h of treatment, the antifeedant rate of the chloroform extract against 3rd instar larvae of S. litura at 2.5 mg/mL was 55.62% and 52.66%, respectively. The chloroform extract was further separated through silica gel column and the fractions were  monitored with analytical thin layer chromatography (TLC). Fourteen fractions were obtained and also tested for their antifeedant activity against S. litura larvae. The bioassay results showed that fraction 4 and 10 at 1 mg/mL had higher antifeedant activity to 3rd instar larvae of S. litura than other fractions. The antifeedant rate of fraction 4 was 56.01% in 24 h of treatment and 38.06% in 48 h of treatment, while that of fraction 10 was 51.56% in 24 h of treatment and 64.30% in 48 h of treatment. The inhibiting activity of the two fractions against two digestive enzymes lipase and α-amylase from the midgut of S. litura was tested. The results showed that the activity of both enzymes was inhibited effectively by the two fractions. The inhibiting rates of fraction 4 and 10 at 1 mg/mL against α-amylase activity of 3rd instar larvae of S. litura were 25.06% and 27.40% in 72 h of treatment, respectively. Fraction 10 could inhibit the activity of lipase of 3rd instar larvae of S. litura significantly, with the inhibiting rate 19.82% in 48 h of treatment and 34.60% in 72 h of treatment, respectively. The results of assay suggested that the digestive enzymes of the midgut of S. litura might be the action targets of the active ingredients fromO. punctata.

Key words: Oryza punctata, Spodoptera litura, antifeeding component, lipase, α-amylas