摘要
大气中CO_(2)浓度增加直接或间接影响昆虫的发生和为害,可能会影响入侵害虫的危害性及其与本地近缘种的互作关系。然而,CO_(2)浓度升高对入侵害虫草地贪夜蛾Spodoptera frugiperda及其本地近缘种斜纹夜蛾Spodopteralitura种间竞争的影响尚不清楚。本研究模拟环境条件,设置了CO_(2)正常浓度(400μL/L)和倍增浓度(800μL/L),将草地贪夜蛾幼虫与斜纹夜蛾幼虫以25/5、20/10、15/15、10/20和5/25的比例混合,分别在寄主植物小麦和人工饲料上饲养,比较研究了CO_(2)浓度升高对其种间竞争关系的影响。结果表明:(1)在所有试验处理中,斜纹夜蛾幼虫的死亡率均会达100%,而且在高CO_(2)浓度环境下斜纹夜蛾幼虫全部死亡所需时间更短。而高CO_(2)浓度下,又以小麦为食的25/5和20/10混合比例中用时最短,仅需4.00 d;(2)各混合比例中,草地贪夜蛾幼虫的平均存活天数均显著高于斜纹夜蛾幼虫,其中在高CO_(2)浓度下以小麦为食时,各混合比例中草地贪夜蛾幼虫较斜纹夜蛾幼虫平均存活天数的差距最大,分别为5.99 d、6.96 d、6.22 d、6.15 d和5.21 d。而且高CO_(2)浓度下草地贪夜蛾幼虫与斜纹夜蛾幼虫的平均存活天数相对值均高于正常CO_(2)浓度对照组,其中在以小麦为食时,高CO_(2)浓度组的平均存活天数相对值分别达到正常CO_(2)浓度的1.08倍、1.22倍、1.26倍、1.31倍和1.13倍;(3)两种CO_(2)浓度下草地贪夜蛾幼虫的平均相对生长率均高于斜纹夜蛾幼虫,而且高CO_(2)浓度下草地贪夜蛾幼虫与斜纹夜蛾幼虫的平均相对生长率相对值高于对照,其中在以饲料为食时,在比例25/5、20/10、15/15中,分别达到正常CO_(2)浓度的168.03倍、3.38倍和2.91倍。由此说明,在两种CO_(2)浓度下,草地贪夜蛾幼虫与斜纹夜蛾幼虫在小麦和人工饲料上的种间竞争中,草地贪夜蛾幼虫均具有较强的竞争优势,尤其在高CO_(2)浓度下,更有利于其竞争力的发挥。研究结果为揭示未来CO_(2)浓度升高对入侵害虫草地贪夜蛾种群适应性的影响及其科学防控提供了基础数据。
The increase in atmospheric CO_(2)concentration has direct and indirect effects on the occurrence and harm caused by insects,which can impact the destructive potential of invasive pests and their interactions with local species.However,the specific effects of increasing CO_(2)concentration on the competition between the invasive species Spodoptera frugiperda and its local relative Spodoptera litura are still unclear.In this study,we investigated the impact of elevated CO_(2)levels(400 and 800μL/L)on interspecific competition by feeding mixed populations of S.frugiperda and S.litura with wheat and artificial diets in different ratios(25/5,20/10,15/15,10/20,and 5/25,respectively).The findings of the study were as follows:(1)S.litura experienced 100%mortality in all mixed populations under different CO_(2)treatments,with higher CO_(2)concentrations resulting in shorter time to death.The shortest time(4 days)was observed in the 25/5 and 20/10 wheat-based mixed ratios.(2)S.frugiperda exhibited significantly higher average survival days compared to S.litura in all mixing ratios.Among the different mixing ratios,the average survival days of S.frugiperda showed the most significant difference when wheat was used as food under elevated CO_(2)concentration,ranging from 5.21 to 6.96 days.Both S.frugiperda and S.litura had higher average survival days relative to the control group under high CO_(2)concentration,ranging from 1.08 to 1.31 times of normal CO_(2)concentration.(3)S.frugiperda had a higher average relative growth rate than S.litura under both CO_(2)concentrations,and both species exhibited higher growth rates compared to the control group under elevated CO_(2)concentration.Specifically,when feeding on artificial diets,the ratio of 25/5,20/10,and 15/15 showed growth rates that were 168.03,3.38,and 2.91 times higher,respectively,than the normal CO_(2)concentration.In conclusion,S.frugiperda demonstrated a significant competitive advantage over S.litura in interspecific competition under both CO_(2)concentrations,regardless of the type of diet provided.This advantage was particularly pronounced under elevated CO_(2)concentrations,favoring S.frugiperda s competitiveness.These findings contribute to our understanding of how increasing CO_(2)concentration affects the population adaptability of invasive species like S.frugiperda.
作者
陶旋
鲁智慧
何文
陈亚平
桂富荣
孙仲享
TAO Xuan;LU Zhi-Hui;HE Wen;CHEN Ya-Ping;GUI Fu-Rong;SUN Zhong-Xiang(Plant Protection College,Yunnan Agricultural University,State Key Laboratory for Conservation and Utilization of Bioresources in Yunnan,Kunming 650201,China)
出处
《环境昆虫学报》
CSCD
北大核心
2024年第2期418-430,共13页
Journal of Environmental Entomology
基金
国家重点研发专项(2021YFD1400701)
国家自然科学基金(32260668)。
关键词
高CO_(2)浓度
草地贪夜蛾
斜纹夜蛾
种间竞争
存活率
相对生长率
Elevated CO_(2)
Spodoptera frugiperda
Spodoptera litura
interspecific competition
survival rate
relative growth rate
