• Alfiya Thomas
• Binoy C F

Predatory efficiency of nymphal stages of dragonfly Rhyothemis variegata on the larval instars of Aedes, Anopheles and Culex mosquitoes were evaluated under simulated conditions. R. variegata nymphs were collected and were reared by providing mosquito larvae as their food. The observations were conducted between 10.00 AM to 6.00 PM. R. variegata showed preference for Aedes larvae than Anopheles and Culex probably because both R. variegata and Aedes larvae shared a common habitat; stagnant fresh water pools. R. variegata mostly consumed third instar larvae of Aedes (70.6%) followed by second instar (38.6%) larvae. The maximum consumption rate in Anopheles (34.6%) and Culex (28.6%) were significantly less when compared to Aedes. Percentage consumption was higher for the third instar larvae in all selected mosquitoes (F< 0.01). The experiments on prey choice among the four larval stages suggested that prey size affected predatory efficiency. Mortality was observed in the fourth instar larvae of all mosquito species due to the injury caused by R. variegata during prey capture. The maximum predation rate was recorded during the initial period of observation between 10.00 AM to 12.00 Noon and gradually decreased.

R. variegata, Aedes, Anopheles, Culex, predatory efficiency, biological control.

"Rhyothemis Variegata Linnaeus (Odonata: Libellulidae): A Potent Biocontrol Agent Against Common Mosquito Larvae In Thrissur District, Kerala", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.6, Issue 6, page no.361-365, June-2019, Available :http://www.jetir.org/papers/JETIR1906196.pdf

"Rhyothemis Variegata Linnaeus (Odonata: Libellulidae): A Potent Biocontrol Agent Against Common Mosquito Larvae In Thrissur District, Kerala", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.6, Issue 6, page no. pp361-365, June-2019, Available at : http://www.jetir.org/papers/JETIR1906196.pdf