Kenawy M A, Rashed S S, Teleb S S
Department of Entomology, Faculty of Science, Ain Shams University, Cairo, Egypt.
J Egypt Soc Parasitol. 1998 Aug;28(2):449-59.
The characteristics of the breeding water, interspecific association and seasonal abundance of 3 mosquito species within rice fields were examined in 6 districts. Larvae of Cx. antennatus were dominant (83.71% collected larvae), of An pharoensis were common (12.29%) and of Cx perexiguus were uncommon (4.0 = .0%). Breeding water has pH of 6-8, salinity of 0.05-0.35 gm Cl/L. and temperature of 21-29 degrees C. Although the relation of larval density (for each species) was positive with pH and negative with salinity and temperature however, no interaction (regression analysis) was existed among the variables (R = 0.26-0.40, P > 0.05). Significant and complete associations (CAB = 1.0, P < 0.01) were detected for Cx. antennatus with other species. During rice growing period (June to October), Cx perexiguus larvae were quite short lasting (June to August). Larval abundance varied monthly in relation to the plant growth stage. No larvae of any species were collected in short plant (< 20 cm, beginning of June) or in very long ones (130 cm in October). Higher numbers of larvae were often associated with the moderate plant growth (50-80 cm) with a peak in plants of 70 cm height in August (161.50 larvae/10 net dips for the 3 species). The highest larval density for Cx antennatus (132.50 larvae) and An pharoensis (22.25 larvae) were during August (70 cm plant) and for Cx. perexiguus (7.67 larvae) was in July (60 cm plant). So, rice fields are potential habitats for these disease vectors. The plant height and irrigation scheme are major factors affecting the abundance of these species.
在6个地区对稻田内3种蚊虫的孳生水体特征、种间关联及季节丰度进行了调查。触角伊蚊幼虫占主导地位（采集到的幼虫占83.71%），法老伊蚊幼虫较为常见（占12.29%），微小按蚊幼虫不常见（占4.0%）。孳生水体的pH值为6 - 8，盐度为0.05 - 0.35克氯/升，温度为21 - 29摄氏度。尽管幼虫密度（每种蚊虫）与pH值呈正相关，与盐度和温度呈负相关，但变量之间不存在相互作用（回归分析）（R = 0.26 - 0.40，P > 0.05）。触角伊蚊与其他物种之间存在显著且完全的关联（CAB = 1.0，P < 0.01）。在水稻生长期间（6月至10月），微小按蚊幼虫持续时间较短（6月至8月）。幼虫丰度随植物生长阶段每月变化。在矮小植株（6月初<20厘米）或非常高大的植株（10月130厘米）中未采集到任何物种的幼虫。较多数量的幼虫通常与中等生长的植株（50 - 80厘米）相关，8月植株高度为70厘米时出现高峰（3种蚊虫每10次网捞幼虫数为161.50条）。触角伊蚊幼虫密度最高（132.50条）出现在8月（植株70厘米时），法老伊蚊幼虫密度最高（22.25条）出现在8月（植株70厘米时），微小按蚊幼虫密度最高（7.67条）出现在7月（植株60厘米时）。因此，稻田是这些病媒的潜在栖息地。植株高度和灌溉方案是影响这些物种丰度的主要因素。
