TY - JOUR

T1 - Plant resistance in different cell layers affects aphid probing and feeding behaviour during poor- and non-host interactions

AU - Escudero-Martinez, Carmen

AU - Leybourne, Daniel J.

AU - Bos, Jorunn I.B.

N1 - Funding Information: The authors thank Dr Freddy Tjallingii (EPG Systems, The Netherlands), Professor Alberto Fereres (CSIC, Spain) and Professor Gregory Walker (University of California, Riverside, USA) for providing EPG training, and additional thanks to Dr Tjallingii for helpful comments on non-host EPG waveforms. They also thank Dr A. Nicholas E. Birch (The James Hutton Institute) for allowing us to use the EPG equipment. This work was supported by the European Research Council (310190-APHIDHOST to JIBB), and the James Hutton Institute and Universities of Aberdeen and Dundee through a Scottish Food Security Alliance (Crops) PhD studentship to DJL.

PY - 2021/2

Y1 - 2021/2

N2 - Aphids are phloem-feeding insects that cause economic losses to crops globally. Whilst aphid interactions with susceptible plants and partially resistant genotypes have been well characterized, the interactions between aphids and non-host species are not well understood. Unravelling these non-host interactions can identify the mechanisms which contribute to plant resistance. Using contrasting aphid-host plant systems, including the broad host range pest Myzus persicae (host: Arabidopsis; poor-host: Barley) and the cereal pest Rhopalosiphum padi (host: Barley; non-host: Arabidopsis), we conducted a range of physiological experiments and compared aphid settling and probing behaviour on a host plant vs either a non-host or poor-host. In choice experiments, we observed that around 10% of aphids selected a non-host or poor-host plant species after 24 h. Using the Electrical Penetration Graph technique, we showed that feeding and probing behaviours differ during non-host and poor-host interactions when compared with a host interaction. In the Arabidopsis non-host interaction with the cereal pest R. padi aphids were unable to reach and feed on the phloem, with resistance likely residing in the mesophyll cell layer. In the barley poor-host interaction with M. persicae, resistance is likely phloem-based as phloem ingestion was reduced compared with the host interaction. Overall, our data suggest that plant resistance to aphids in non-host and poor-host interactions with these aphid species likely resides in different plant cell layers. Future work will take into account specific cell layers where resistances are based to dissect the underlying mechanisms and gain a better understanding of how we may improve crop resistance to aphids.

AB - Aphids are phloem-feeding insects that cause economic losses to crops globally. Whilst aphid interactions with susceptible plants and partially resistant genotypes have been well characterized, the interactions between aphids and non-host species are not well understood. Unravelling these non-host interactions can identify the mechanisms which contribute to plant resistance. Using contrasting aphid-host plant systems, including the broad host range pest Myzus persicae (host: Arabidopsis; poor-host: Barley) and the cereal pest Rhopalosiphum padi (host: Barley; non-host: Arabidopsis), we conducted a range of physiological experiments and compared aphid settling and probing behaviour on a host plant vs either a non-host or poor-host. In choice experiments, we observed that around 10% of aphids selected a non-host or poor-host plant species after 24 h. Using the Electrical Penetration Graph technique, we showed that feeding and probing behaviours differ during non-host and poor-host interactions when compared with a host interaction. In the Arabidopsis non-host interaction with the cereal pest R. padi aphids were unable to reach and feed on the phloem, with resistance likely residing in the mesophyll cell layer. In the barley poor-host interaction with M. persicae, resistance is likely phloem-based as phloem ingestion was reduced compared with the host interaction. Overall, our data suggest that plant resistance to aphids in non-host and poor-host interactions with these aphid species likely resides in different plant cell layers. Future work will take into account specific cell layers where resistances are based to dissect the underlying mechanisms and gain a better understanding of how we may improve crop resistance to aphids.

KW - Aphid

KW - EPG analyses

KW - nonhost

KW - plant resistance

KW - probing

KW - stylet pathway

UR - http://www.scopus.com/inward/record.url?scp=85088981018&partnerID=8YFLogxK

U2 - 10.1101/372839

DO - 10.1101/372839

M3 - Article

C2 - 32539886

AN - SCOPUS:85088981018

VL - 111

SP - 31

EP - 38

JO - Bulletin of Entomological Research

JF - Bulletin of Entomological Research

SN - 0007-4853

IS - 1

ER -