Effect of insect growth regulator, chromafenozide on the food consumption and metabolic efficiencies of the desert locust

Abstract

The objective of the current investigation was to assess the food deterrence property of chromafenozide and its impact on different food metabolic parameters of the 5 th instar nymphs of the desert locust Schistocerca gregaria. For this purpose, three doses (10, 100 and 150 µg/nymph) were topically applied (once) onto the newly molted last (5 th ) instar nymphs. chromafenozide exhibited contradictory effects on the feeding since it acted as a weak antifeedant against female nymphs only at the lowest dose but acted as phagostimulant against their congeners at the higher two doses. Furthermore, the compound exerted a general phagostimulant action on the male nymphs, regardless the dose. The food intake by the last nymphal instar females was slightly reduced only at only the lowest dose but remarkably increased at the higher doses. The male nymphs had been promoted to consume more food amount. Treated nymphs of both sexes attained slightly or significantly increasing relative weight gain and discharged more frass pellets. The treated nymphs of both sexes achieved slightly increasing approximate digestibility (AD), with two exceptions for the male nymphs which had a slightly decreased AD at the medium dose and unaffected AD at the highest dose. Both the efficiency of conversion of ingested food into biomass (ECI) and efficiency of conversion of digested food into biomass (ECD) of the female nymphs slightly increased. ECI of male nymphs was enhanced but ECD was slightly inhibited. Depending on the present results, Chromafenozide cannot be recommended as a promising agent for controlling S. gregaria.

Geometric morphometrics of three species of the genus Dociostaurus (Orthoptera: Acrididae) from the Middle Atlas of Morocco

“…For several years, investigators have investigated the factors influencing the voracity and agricultural impact of Acrididae (Pincebourde et al 2017;Dakhel et al 2020). Results showed that a wide diet spectrum and intense food consumption are considered the main factors (Basiouny and Ghoneim 2021;Egonyu et al 2021). Acrididae are known for the intestinal diversity of microbial and enzymatic capacities, and these allow the consumption and digestion of food in large quantities (Zahri et al 2021).…”