Mutero C M, Ng'ang'a P N, Wekoyela P, Githure J, Konradsen F
International Water Management Institute (IWMI), Private Bag X813, 0127, Silverton, Pretoria, South Africa.
Acta Trop. 2004 Jan;89(2):187-92. doi: 10.1016/j.actatropica.2003.08.006.
Field experiments were conducted in central Kenya, to study the effect of ammonium sulphate fertiliser ((NH(4))(2)SO(4)) on mosquito larval populations in rice fields. The experiments used a complete randomised block design having four blocks with two experimental ponds per block, and the fertiliser and control treatments allocated randomly among the ponds. Student's two-sample unpaired t-test was used to test for the significance of differences between the relative counts of larvae in fertiliser and control treatments. The results showed a significant overall increase in the larval populations of An. arabiensis (P<0.01) and culicine mosquitoes (P<0.05), after ponds were treated with the fertiliser. Significantly more fourth instar larvae of An. arabiensis were collected in fertiliser than control plots (P<0.001). An. arabiensis data indicated that the first fertiliser application had the most impact, compared to the second and third applications. This was evident in a significant peak of combined first and second instar An. arabiensis larvae observed 5 days after the first fertiliser application (P<0.05). The studies suggest that ammonium sulphate fertiliser reduces turbidity of water in rice fields, thereby making them visually more attractive for egg-laying by An. arabiensis and culicine mosquitoes.
在肯尼亚中部开展了田间试验，以研究硫酸铵肥料[（NH₄）₂SO₄]对稻田中蚊虫幼虫种群的影响。试验采用完全随机区组设计，有4个区组，每个区组有两个试验池塘，肥料处理和对照处理在池塘间随机分配。采用学生双样本非配对t检验来检验肥料处理和对照处理中幼虫相对数量差异的显著性。结果显示，在用肥料处理池塘后，阿拉伯按蚊（P<0.01）和库蚊（P<0.05）的幼虫种群总体上显著增加。在施肥地块收集到的阿拉伯按蚊四龄幼虫明显多于对照地块（P<0.001）。阿拉伯按蚊的数据表明，与第二次和第三次施肥相比，第一次施肥的影响最大。这在第一次施肥后5天观察到的一龄和二龄阿拉伯按蚊幼虫总数显著峰值中很明显（P<0.05）。研究表明，硫酸铵肥料降低了稻田水的浊度，从而使稻田在视觉上对阿拉伯按蚊和库蚊更具产卵吸引力。
