Laboratory evaluation of Novalurone as an Insect Growth Regulator (IGR) against the immature DDT resistant Phlebotomus argentipes (Diptera: psychodidae)

Abstract

Female sand flies Phlebotomus argentipes are well-established pathogen transmitter for Visceral Leishmaniasis (VL) among humans and Dichlorodiphenyltrichloroethane (DDT) served as an important tool for controlling their population. After the decades of DDT use, P. argentipes has developed resistance against it affecting every aspect of vector control at grass-root level. In a way of exploring new 'strategic weapon' against sand flies, Novalurone -a noble Insect Growth Regulators (IGRs), inhibiting life-cycle and checking insect population at their non-infective stage has been evaluated for the first time ever against the laboratory colonized DDT resistant sand flies. It was observed that DDT resistant sand flies tolerating insecticide pressure successfully exhibited susceptibility at highest concentration of Novalurone processed larval diet (i.e., at 150000 ppm) following slowed growth rate that doesn't allowed them to metamorphed into the pupal stage. Moreover, their survival (1.8±94.50) was observed to be lasted till 2 nd stage only in which they attained absolute mortality. These preliminary laboratory based results certifies Novalurone to be very much effective for nailing effective checks upon natural growth process of immature DDT resistant sand flies and hence could be incorporated as an important preposition as alone or as a synergist with insecticide for total and long-lasting control over the VL vector population.