Life table of Xestia c-nigrum(Lepidoptera:Noctuidae)population at different temperatures and the dynamics of field adults captured in light trap in Korla,Xinjiang,Northwest China
[Aim]To assess the effects of temperature on the growth,development and reproduction of Xestia c-nigrum in Korla,Xinjiang,Northwest China,and to explore its adaptability to environmental temperature.[Methods]The egg hatching rates,larval survival rates,pupation rates,eclosion rates,developmental duration and fecundity of X.c-nigrum at 15,20,25,30 and 35 ℃ were compared by using two-sex life table method,and the effects of different temperatures on the life table parameters of the population were analyzed.The developmental threshold temperatures and effective accumulated temperatures of X.c-nigrum at different developmental stages were also determined.During 2020-2022,the relationship between the population dynamics of X.c-nigrum by light-trapping and the daily average temperature change in Korla,Xinjiang was analyzed.[Results]At 15 ℃,the larval survival rate,pupation rate,and eclosion rate of X.c-nigrum were lower than 30％.At 30 ℃,the larval survival rate and pupation rate were lower than 10％,and the pupa could not normally emerge.At 35 ℃,the larvae could not survive.The duration of different developmental stages of X.c-nigrum shortened as the temperature rose,and the egg duration was 15.52,7.40,5.47,4.88 and 3.88 d at 15,20,25,30 and 35 ℃,respectively.The larval duration was 109.43,40.53,26.47 and 24.55 d at 15,20,25 and 30 ℃,respectively.The pupal duration was 41.43,18.00 and 12.54 d at 15,20 and 25 ℃,respectively.The pupal duration was 41.4,18.0 and 12.5 d at 15,20 and 25 ℃,respectively.The population showed negative growth at 15 ℃,and positive growth at 20 and 25 ℃,with the highest intrinsic rate of increase(rm)at 25 ℃.The developmental threshold temperatures of egg,1 st-6th instar larvae and pupa were 9.81,8.43,9.95,10.26,12.52,13.58,12.60 and 10.81 ℃,respectively,and the effective accumulated temperatures were 79.62,92.17,56.09,57.03,39.35,38.16,80.72 and 172.39 degree-days,respectively.The monitored data from light-trapping during 2020-2022 showed that X.c-nigrum had three generations per year in Korla,Xinjiang,and the adult peak periods were in mid-May,late July and early September,with the average daily temperature range of 19.5-26.5 ℃.[Conclusion]The population of X.c-nigrum shows negative growth when the temperature is lower than 15 ℃,and cannot complete its life cycle at over 30 ℃,moreover,20-25 ℃ is more suitable for its growth and reproduction.This study provides a scientific basis for clarifying the temperature adaptability and its occurrence and dynamics of X.c-nigrum in Korla,Xinjiang.
Xestia c-nigrumlife table parameterstemperaturedevelopmental durationpopulation dynamicstwo-sex life table
万方数据
维普
