Kumar Gaurav, Singh R K, Pande Veena, Dhiman R C
National Institute of Malaria Research (ICMR), New Delhi, India.
Department of Biotechnology, Kumaun University, Nainital, Uttarakhand, India.
J Vector Borne Dis. 2016 Apr-Jun;53(2):144-8.
BACKGROUND & OBJECTIVES: Aedes aegypti, the primary vector of dengue generally breeds in intradomestic and peridomestic containers made up of different materials, i.e. plastic, iron, rubber, earthen material etc. The material of container is likely to affect the temperature of water in container with variation in environmental temperature. The present study was aimed to determine the effect of different container materials on larval development of Ae. aegypti at different temperatures.
Newly hatched I instar larvae (2-4 h old) were used in the study and experiments were conducted using three different containers made up of plastic, iron and earthen material. Three replicates for each type of container at 22, 26, 30, 34, 38, 40, and 42°C were placed in environmental chamber for the development of larvae.
At temperatures >22°C, 50% pupation was completed in earthen pot within 4.3±0.6 to 6.3±0.6 days followed by plastic containers (5±0 to 8±0 days) and iron containers (6±0 to 9±0 days). Developmental time for 50% pupation in the three containers differed significantly (p < 0.05) at all the experimental temperature ranges. A significant variation was found in the temperature of environmental chamber and the temperature of water in three types of containers (p < 0.05). The difference in the temperatures of water in different containers resulted in significant variations in the developmental period of larvae. More than 35°C temperature of water was found inimical for pupal development.
INTERPRETATION & CONCLUSION: The results revealed the variation in temperature of water in different types of containers depending on the material of container, affecting duration of larval development. As the larval development was faster in earthen pot as compared to plastic and iron containers, community should be discouraged for storing the water in earthen pots. However, in view of containers of different materials used by the community in different temperature zones in the country, further studies are required for devising area-specific preventive measures for Aedes breeding.
埃及伊蚊是登革热的主要传播媒介，通常在家庭内部和周边由不同材料制成的容器中繁殖，如塑料、铁、橡胶、陶土等材料。随着环境温度的变化，容器材料可能会影响容器内水的温度。本研究旨在确定不同容器材料在不同温度下对埃及伊蚊幼虫发育的影响。
本研究使用刚孵化的I龄幼虫（2 - 4小时龄），并使用由塑料、铁和陶土材料制成的三种不同容器进行实验。每种类型的容器在22、26、30、34、38、40和42°C下设置三个重复，放置在环境箱中进行幼虫发育实验。
在温度>22°C时，陶土罐中50%的幼虫在4.3±0.6至6.3±0.6天内完成化蛹，其次是塑料容器（5±0至8±0天）和铁容器（6±0至9±0天）。在所有实验温度范围内，三种容器中50%幼虫化蛹的发育时间差异显著（p < 0.05）。发现环境箱温度和三种类型容器内水的温度存在显著差异（p < 0.05）。不同容器内水的温度差异导致幼虫发育时期出现显著变化。发现水温超过35°C对蛹的发育不利。
结果表明，不同类型容器内水的温度因容器材料而异，这影响了幼虫发育的持续时间。由于与塑料和铁容器相比，陶土罐中幼虫发育更快，应劝阻社区使用陶土罐储存水。然而，鉴于该国不同温度区域社区使用不同材料的容器，需要进一步研究以制定针对埃及伊蚊繁殖的特定区域预防措施。
