title: Emergence of the overwintering generation of peach fruit moth (Carposina sasakii) depends on diapause and spring soil temperatures.
abstract: Survival rate and emergence timing of the overwintering generation of many temperate agricultural pests is expected to affect their population dynamics and damage potential. However the impact of fluctuating winter and spring conditions on the successful emergence of insects post-diapause is generally poorly known. Here we characterize diapause responses in the peach fruit moth (PFM) pest, Carposina sasakii Matsumura, which overwinters at the larval stage in soil. Temperatures at a depth of 5 cm fluctuated markedly in early spring during the critical PFM post-diapause period (late December to mid-April). By removing outdoor larval samples over this period, we show that the completion of diapause for PFM in northern China starts from late January and continues until March. This extended developmental period is accompanied by an ongoing loss of cold resistance. Temperature conditions experienced in the field were associated with cold tolerance and emergence times, and reduced cold tolerance was associated with shorter emergence time. Cryoprotectants declined from late December, and levels were associated with changes in the supercooling point (SCP) of the larvae, but both correlated weakly to survival under cold stress during the post-diapause period. These findings suggest that diapause stage and soil temperatures should be taken into account when predicting field dynamics of soil-dwelling overwintering insects based on degree day accumulation models and other approaches.
authors.affiliation: Group of Climate Change Biology, State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China. Electronic address: zhangbo05@caas.cn.
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
authors.affiliation: Group of Climate Change Biology, State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China. Electronic address: pengyu_420@163.com.
authors.forename: Yu
authors.initials: Y
authors.lastname: Peng
authors.affiliation: Institute of Ecology, Chinese Research Academy of Environmental Sciences, Beijing 100012, China. Electronic address: zhaoxj@craes.org.cn.
authors.forename: Xiang-Jian
authors.initials: XJ
authors.lastname: Zhao
authors.affiliation: School of BioSciences, The University of Melbourne, Melbourne, VIC 3010, Australia. Electronic address: ary@unimelb.edu.au.
authors.forename: Ary A
authors.initials: AA
authors.lastname: Hoffmann
authors.affiliation: Group of Climate Change Biology, State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China. Electronic address: xndlr@sohu.com.
authors.forename: Rui
authors.initials: R
authors.lastname: Li
authors.affiliation: Group of Climate Change Biology, State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China. Electronic address: machunsen@caas.cn.
authors.forename: Chun-Sen
authors.initials: CS
authors.lastname: Ma
mesh_terms: D000818:Animals; D064666:Diapause, Insect; D007814:Larva / Q000254:growth & development; D009036:Moths / Q000254:growth & development*; D012987:Soil; D013696:Temperature
chemical_list: D012987:Soil
keywords: Carposina sasakii; Cold tolerance; Cryoprotectant; Diapause termination; Post-diapause development; Soil temperature