TITLE:
Physiological and Morphological Responses of Susceptible and Resistant Barleys to Bird Cherry-Oat Aphid Feeding
AUTHORS:
Rafael Hayashida, John Scott Armstrong, William Wyatt Hoback, Dolores Mornhinweg
KEYWORDS:
Plant Tolerance, Hemiptera, Piercing-Sucking Injury, Cereal Crops
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.14 No.10,
October
11,
2023
ABSTRACT: The bird cherry-oat aphid (Rhopalosiphum padi [Linnaeus, 1758]) is considered a key pest of
cereal crops worldwide, causing direct damage through sap feeding and by acting
as a vector for viral diseases. Managing aphids is challenging because of their
biology and potential resistance to insecticides. Developing resistant barley
genotypes is a sustainable strategy for managing BCOA. In this study, we assessed responses of susceptible “Morex” and
resistant “BCO R001” barley, Hordeum vulgare L. genotypes to different initial BCOA densities
(0, 50, 100 or 200 aphids.plant-1). Physiological and morphological
parameters were measured weekly for four weeks after infestation. Chlorophyll
content, photosynthetic rate, plant aerial fresh and dry weight were greater
for the resistant cultivar at lower aphid abundances and up to three weeks
after infestation. Carbon assimilation curves (A/Ci) of infested “BCO R001”
were similar to controls 15 days post infestation, differing from Morex.
However, BCOA infestation of 50 aphid.plant-1 for two weeks negatively
impacted the fitness of both genotypes. Initial resistance by BCO R001 to BCOA
infestation can allow growers and natural enemies more time contributing to
more effective and sustainable management of BCOA infestations.