Influence of Variable Photoperiod on Life-stages Mobilization of Teneral Reserves in Culex quinquefasciatus (Diptera: Culicidae): Implication for Environmental Manipulation for Vector Control

Abstract

The influence of photoperiod on teneral reserve accumulation across life stages of Culex quinquefasciatus was investigated in this study. Day-old larvae of the mosquito were exposed to five simulated photoperiodic regimens, namely 0, 6, 12, 18 and 24 hours of Light (hL) and a Control (prevailing 13 hL). Rearing of immature stages and quantification of teneral components (lipid, glucose, protein and glycogen) at the life stages were done following standard protocols. Results revealed significant effects of photoperiod on teneral components in all life stages. Generally, there were significant increase in all teneral components as the larvae progressed from L1 to L4 instars, with subsequent reduction at pupal and adult stages. The quantities of teneral components also exhibited an inverse relationship with photo-duration, with glycogen and protein more distributed than lipid and glucose. Average immature component ranged from 12.05±0.30 to 23.95±0.15, 7.66±0.43 to 13.62±0.29, 38.06±0.70 to 61.97±0.44, and 20.19 ±0.58 to 38.30±0.47 μg /mosquito, for lipid, glucose, glycogen and protein, respectively. While Adult values were, respectively, ranged from 10.47±0.36 to 25.29±0.99, 6.46±0.30 to 15.22±0.90, 33.54±1.94 to 67.66±0.49 and 17.29±0.45 to 41.04±0.24 μg/mosquito. The present study showed that photoperiod had significant influence on teneral reserves of Cx. Quinquefasciatus mosquito.