Effect of Citrullus colocynthis (Cucurbitaceae) agglutinin on the life table parameters of Apomyelois ceratoniae (Lepidoptera: Pyralidae)

Abstract

A Castanea crenata agglutinin (abbreviated as CCA) was extracted and purified from bitter apple, Citrullus colocynthis L., to determine its effects on the demographic parameters of Apomyelois ceratoniae Zeller. Two groups of first larval instars were reared on an artificial diet containing 2% (w/w) of CCA and control diets until emergence of adults. Two Sex MS-chart life table software was used to analyze data and calculate life table parameters. Developmental times of larvae in control and CCA diets showed statistical differences for male, female except for third and fourth larval instars. It was found that A. ceratoniae larvae fed on control had a survival of 18 days but individuals fed on CCA diet survived for 12 days. The highest fecundity values of individuals fed on control and CCA diets were obtained at the age of 30 and 27 days, respectively. Adult longevity, pre-oviposition period, oviposition period and mean fecundity of A. ceratoniae fed on control were higher than those of individuals fed on CCA diet. The probabilities of a newborn egg surviving to age 28 days were 0.42 and 0.3 for control and CCA, respectively. Each female started egg laying on day 22 for control and 25 for CCA. Life expectancies of a newly laid egg were 29 days for control and 26 days for CCA treatment. Life table parameters except for mean generation time showed statistical differences between control and CCA treatments. These results demonstrated the negative effects of CCA on life table parameters of A. ceratoniae that might lead to a promising and alternative way to suppress population increase and damage caused by A. ceratoniae.