Phenotypic plasticity of Myzus persicae (Hemíptera: Aphididae) raised on Brassica oleracea L. var. acephala (kale) and Raphanus sativus L. (radish)

Abstract

The study of variability generated by phenotypic plasticity is crucial for predicting evolutionary patterns in insect-plant systems. Given sufficient variation for plasticity, host race formation can be favored and maintained, even simpatrically. The plasticity of size and performance (assessed by the lifetime fitness index r m ) of six clones of Myzus persicae was tested, with replicates allowed to develop on two hosts, kale (Brassica oleracea var. acephala) and radish (Raphanus sativus). The clones showed significant variability in their plasticity. Reaction norms varied through generations and negative genetic correlation, although not significant, tend to increase with the duration of host use. The lack of plasticity in lifetime fitness among generalist clones occurred as an after-effect of the highly plastic determinants. Significant morphological plasticity in host used was observed, but no variation in the plastic responses (GxE interaction) was detected. Strong selection for a larger size occurred among individuals reared on radish, the most unfavorable host. Morphological plasticity in general body size (in a multivariate sense) was not linear related to fitness plasticity. These observations suggest that a high potential for the evolution of host divergence favors host race formation.

Have Genetic Trade-Offs in Host Use been Overlooked in Arthropods?

“…Studies using environmentÂgenetic interactions (GÂE) only were not included as a significant GÂE interaction does not necessarily indicate genetic trade-off (see Falconer and McKay, 1996;Roff, 1997 on p. 206). Recent examples of studies that found significant GÂE interactions but no evidence for a negative genetic correlation in performance are for instance Peppe and Lomoˆnaco (2003) and Ueno et al (2003). We also noted whether the arthropod species is able to reproduce asexually (including cyclic parthenogenesis like aphids and gynogenetic reproduction like in Alsophila pometaria) or is obligate sexually.…”

Evidence of selection on phenotypic plasticity and cost of plasticity in response to host-feeding sources in the major Chagas disease vector Triatoma infestans

“…In the aphid Myzus persicae, strong selection for larger body size occurred among individuals reared on an unfavorable host plant (Peppe and Lomônaco, 2003), whereas in the gypsy moth Lymantria dispar phenotypic selection analyses revealed that specific activities of digestive enzymes were adaptive (Mrdaković et al, 2014).…”

Revision and Phylogenetic Analysis of the Hadronema Group (Miridae: Orthotylinae: Orthotylini), With Descriptions of New Genera and New Species, and Comments on the Neotropical Genus Tupimiris

“…Using CVA to discriminate among groups within the complex of A. princeps, A. uhleri, A. uniforme, and the Colorado population (Agrawal, 2001;Carrol and Boyd, 1992;Kirk, 1991;Mopper, 1996;Peppe and Lomô naco, 2003). Nutritional quality of host plants is probably the most important factor to influence insect size (e.g., Amarillo-Suárez and Fox, 2006;Clissold et al, 2006).…”