谷子专题

Heat sensitivity of eggs attributes to the reduction in Agasicles hygrophila population

期刊:INSECT SCIENCE ISSN:1672-9609 , 年:2020 . 卷:27 . 期:1   页码:159-169

语种: English 

原文链接:http://dx.doi.org/10.1111/1744-7917.12611

摘要
Agasicles hygrophila has been introduced worldwide as a control agent for the invasive weed Alternanthera philoxeroides. However, global warming has potential impact on its controlling efficacy. The aim of this research was to explore the primary factors responsible for the greatly reduced A. hygrophila population in hot summers. To imitate the temperature conditions in summers, different developmental stages of A. hygrophila were treated with high temperatures from 32.5 degrees C to 45 degrees C for 1-5 h. Based on the survival rate, the heat tolerance of each developmental stage was ranked from lowest to highest as follows: egg, 1st, 2nd, 3rd instar larva, adult and pupa. Eggs showed the lowest heat tolerance with 37.5 degrees C as the critical temperature affecting larval hatching. Heat treatment of the A. hygrophila eggs at 37.5 degrees C for 1 h decreased the hatch rate to 24%. Our results indicated that when compared with the control at 25 degrees C, 1 h treatment at 37.5 degrees C prolonged the duration of the egg stage, shortened the duration of oviposition and total longevity, and changed the reproductive pattern of A. hygrophila. The net reproductive rate, intrinsic rate and finite rate were all significantly reduced. The results suggest that low heat tolerance of the eggs was the major factor responsible for the reduction of A. hygrophila populations, and the key temperature was 37.5 degrees C. Therefore, appropriate measures should be taken to protect eggs in order to maintain the efficacy of A. hygrophila in the biological control of A. philoxeroides in hot summers.
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关键词
age-stage two-sex life table;  alligator weed;  flea beetle;  heat tolerance;  population dynamics
作者信息
通讯作者:
     Ma, RY , Shanxi Agr Univ, Coll Agr, Taigu 030801, Shanxi, Peoples R China.; Gao, LL , CSIRO Agr & Food, Ctr Environm & Life Sci, Wembley, WA 6014, Australia.
作者机构:
     [1] [ Jia, Dong;  Liu, Yan-Hong;  Xu, Chao-Qian;  Wang, Yuan-Xin;  ]  Shanxi Agr Univ, Coll Agr, Taigu 030801, Shanxi, Peoples R China.
     [2] [ Yuan, Xiao-Fang ]  Shanxi Agr Univ, Coll Life Sci, Taigu, Shanxi, Peoples R China.
     [3] [ Gao, Ling-Ling ]  CSIRO Agr & Food, Ctr Environm & Life Sci, Wembley, WA 6014, Australia.
作者邮箱:
     Lingling.Gao@csiro.au
     maruiyan2004@163.com