title: Life-history trait plasticity and its relationships with plant adaptation and insect fitness: a case study on the aphid Sitobion avenae.
abstract: Phenotypic plasticity has recently been considered a powerful means of adaptation, but its relationships with corresponding life-history characters and plant specialization levels of insects have been controversial. To address the issues, Sitobion avenae clones from three plants in two areas were compared. Varying amounts of life-history trait plasticity were found among S. avenae clones on barley, oat and wheat. In most cases, developmental durations and their corresponding plasticities were found to be independent, and fecundities and their plasticities were correlated characters instead. The developmental time of first instar nymphs for oat and wheat clones, but not for barley clones, was found to be independent from its plasticity, showing environment-specific effects. All correlations between environments were found to be positive, which could contribute to low plasticity in S. avenae. Negative correlations between trait plasticities and fitness of test clones suggest that lower plasticity could have higher adaptive value. Correlations between plasticity and specialization indices were identified for all clones, suggesting that plasticity might evolve as a by-product of adaptation to certain environments. The divergence patterns of life-history plasticities in S. avenae, as well as the relationships among plasticity, specialization and fitness, could have significant implications for evolutionary ecology of this aphid.
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas (Northwest A&F University), Yangling, Shaanxi 712100, China.|College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Dai
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas (Northwest A&F University), Yangling, Shaanxi 712100, China.|Department of Foreign Languages, Northwest A&F University, Yangling, Shaanxi Province 712100, China.
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Shi
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas (Northwest A&F University), Yangling, Shaanxi 712100, China.|College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Deguang
authors.initials: D
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas (Northwest A&F University), Yangling, Shaanxi 712100, China.|College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Zhaohong
authors.initials: Z
authors.lastname: Ge
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas (Northwest A&F University), Yangling, Shaanxi 712100, China.|College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Da
authors.initials: D
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas (Northwest A&F University), Yangling, Shaanxi 712100, China.|College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Xinjia
authors.initials: X
authors.lastname: Dai
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas (Northwest A&F University), Yangling, Shaanxi 712100, China.|College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Zhihao
authors.initials: Z
authors.lastname: Yi
authors.affiliation: School of Environment and Natural Resources, Renmin University of China, Beijing 100872, China.
authors.forename: Xiuxiang
authors.initials: X
authors.lastname: Meng
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D001042:Aphids / Q000254:growth & development* / Q000502:physiology*; D018554:Avena / Q000469:parasitology; D004777:Environment; D005298:Fertility; D001467:Hordeum / Q000469:parasitology; D006790:Host-Parasite Interactions; D008018:Life Cycle Stages; D010944:Plants / Q000469:parasitology*; D013997:Time Factors; D014908:Triticum / Q000469:parasitology