Seasonal changes in the habitat characteristics on survivability and adult emergence of Aedes albopictus (Skuse) from rural and urban environments of northern Kerala, India

Abstract

The range and spread of dengue cases can be ascribed to the breeding habitat of Aedes albopictus. There is a paucity of scientific information on the influence of the water quality of breeding habitats on adult emergence in Aedes albopictus. The objective of the present study was to evaluate the water quality characteristics responsible for the adult emergence of Aedes albopictus confining to selected urban and rural habitats of northern Kerala, India. Larvae of Aedes albopictus were collected using the dipping method, along with the collection and analysis of water samples following APHA (2017). The larvae were retained in controlled environmental conditions to assess the magnitude of adult emergence. The average larval productivity in both rural and urban areas was almost the same and exhibits a particular seasonal pattern. Both the rural and urban sectors showed substantial variations in the magnitude of adult emergence. The percentage of adult emergence followed a pattern of pre-monsoon > post-monsoon> monsoon season. With a correlation coefficient of 0.036, larval productivity and adult emergence were shown to be positively correlated. EC, TDS, salinity, Na, K, and NO3 showed a positive correlation while temperature, pH, turbidity, chloride, and DO showed a negative correlation with the adult emergence. Multiple regression models revealed temperature (p=0.00), DO (p= 0.007), NO3 (p=0.007), and chloride (p=0.030) as the distinguishing elements in the adult emergence of Aedes albopictus.