Diurnal feeding as a potential mechanism of osmoregulation in aphids  

作　　者：Vamsi Nalam Travis Isaacs Sarah Moh Jessica Kansman Deborah Finke Tessa Albrecht Punya Nachappa 

机构地区：[1]Department of Agricultural Biology,Colorado State University,Fort Collins,Colorado,USA [2]Department of Biology,Purdue University Fort Wayne,Fort Wayne,Indiana,USA [3]Division of Plant Sciences,University of Missouri,Columbia,Missouri,USA

出　　处：《Insect Science》2021年第2期521-532,共12页昆虫科学（英文版）

基　　金：TI,SM,and TA were supported by startup funds provided to VN by Purdue Fort Wayne and Colorado State University.DF and JK were supported by USDA NIFA MO-HAPS0006 and the University of Missouri Research Board.JK was supported by AFRI EWD(2019-67011-29729)from the U.S.Department of Agriculture,National Institute of Food and Agriculture.The authors wish to thank Bruce Arnold for technical support with the electrical penetration graph machine.

摘　　要：Diurnal variation in phloem sap composition has a strong infuence on aphid performance.The sugar-rich phloem sap serves as the sole diet for aphids and a suite of physiological mechanisms and behaviors allowv them to tolerate the high osmotic stress.Here,we tested the hypothesis that night-time feeding by aphids is a behavior that takes advantage of the low sugar diet in the night to compensate for osmotic stress incurred while feeding on high sugar diet during the day.Using the electrical penetration graph(EPG)technique.we examined the eiects of diurmal rhythm on feeding behaviors of bird cherry-oat aphid(Rhopalosiphurm padi L.)on wheat.A strong diurmal rhythm in aphids as indicated by the presence of a cyclical pattern of expression in a core clock gene did not impact aphid feeding and similar feeding behaviors were observed during day and night.The major difference observed between day and night feeding was that aphids spent significantly longer time in phloem salivation during the night compared to the day.In contrast,aphid hydration was reduced at the end of the day-time feeding compared to end of the night-time fepding.Gene expression analysis of R.padi osmoregulatory genes indicated that sugar break down and water transport into the aphid gut was reduced at night.These data suggest that while diumal variation occurs in phloem sap composition,aphids use night time feeding to overcome the high osmotic stress incurred while feeding on sugar-rich phloem sap during the day.

关 键 词：bird cherry-oat aphid diurnal cycle electrical penetration graph hydraion OSMOREGULATION PHLOEM 

分 类 号：Q96[生物学—昆虫学]