title: Impacts of Water Deficiency on Life History of Sitobion avenae Clones From Semi-arid and Moist Areas.
abstract: The climate warming trend appears to be evident with an increasing frequency of drought events in Shaanxi Province of China, which may have contributed to an increase in outbreaks of the English grain aphid, Sitobion avenae (Fabricius). To explore the potential effects of water-deficit stress on aphid outbreak risks, clones of S. avenae were collected from semi-arid and moist areas of Shaanxi. The life histories of collected clones were then compared on wheat under well-watered and moderately water-stressed conditions in the laboratory. Our results demonstrated that semi-arid area clones of S. avenae had longer developmental times, shorter reproductive times, lower fecundities, and lower net reproductive rates compared with moist area clones. Age-specific reproductive rates of moist area clones tended to be higher than those of semi-arid area clones. Significant differences between semi-arid and moist area clones were found for the survival functions when tested under water-stressed conditions, and semi-arid area clones tended to have a lower survival rate than moist area clones throughout their lives. "Population origin" (i.e., semi-arid and moist area clones) and "clone" together explained 62.74-96.56% of the total variance of tested life-history traits, suggesting the genetic basis for differentiation of clones from both areas. Significant differences in correlations, and selection differentials and gradients of life-history traits were also found between clones from both areas, providing further evidence of genetic basis for the life-history differentiation between them. Divergence between clones from both areas and its implications for S. avenae outbreaks are discussed.
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. College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China. dgliu@nwsuaf.edu.cn.
authors.forename: Deguang
authors.initials: D
authors.lastname: Liu
authors.affiliation: Department of Foreign Languages, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Shi
mesh_terms: D000818:Animals; D001042:Aphids / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D002681:China; D003889:Desert Climate; D005260:Female; D020387:Food Chain; D000071421:Life History Traits; D009758:Nymph / Q000235:genetics / Q000254:growth & development; D011157:Population Dynamics; D012098:Reproduction; D014908:Triticum / Q000254:growth & development; D014867:Water / Q000378:metabolism*
chemical_list: D014867:Water
keywords: English grain aphid; cereal crop; drought; life table; water-deficit stress