Medfly Phenotypic Plasticity as A Prerequisite for Invasiveness and Adaptation

Abstract

The hypothesis of this study was that different plant hosts of the medfly Ceratitis capitata may cause variability as a prerequisite for its invasiveness. The main objective was to determine population variability based on medfly wing shape in three favorable medfly host plants (peach, fig and mandarin) from different agroecological growing areas with different pest management practices, and to evaluate phenotypic plasticity as a basis for future expansion into new areas and new hosts. Using geometric morphometric methods across 14 specific landmarks on the medfly wings, 10 populations were tested from infested peach, fig and mandarin fruits, as well as laboratory-grown sterile populations. The studies led to the following main findings: (1) all of the medfly populations that were studied exhibited sexual dimorphism in wing shape; (2) the hosts in which the medfly develops influence wing shape and condition its variability; (3) there is significant variability between laboratory mass-reared sterile and wild individuals in male and female populations; (4) a high phenotypic plasticity of medfly populations was observed along the study sites. Even the low but clearly detected variability between different agroecological conditions and localized variability indicate genotypic stability and high phenotypic plasticity, which can be considered as a prerequisite for medfly invasiveness and dispersal to new areas.

Temperature Sensitivity of Wild-Type, Mutant and Genetic Sexing Strains of Ceratitis capitata

“…Moreover, climate change increases the need to characterize such mutations and is not to be underestimated [ 38 ]. In combination with the invasive character of C. capitata, climate change favoured the shift of its geographic range into new areas [ 39 , 40 ]. On the other hand, climate change can severely affect an AW-IPM programme because temperature changes can influence the sterile males and male mating competitiveness.…”

Population Genetic Structure and Geometric Morphology of Codling Moth Populations from Different Management Systems

“…It is well known that metric traits (wing shape and size) are the first morphological traits to change under the influence of environmental and genetic factors [48,49]. Over the last 20 years, geometric morphometric (GM) has been used to study the genetic variability of different insect species [50][51][52][53][54][55]. In CM populations, GM methods have been used to reveal differences between CM forewings and hindwings as a function of the season (overwintering vs. summer), geographical location, and sex [56].…”