P-1: Incidence of resistance to pyrethroids and carbamates in Czech populations of green peach aphid (Myzus persicae) from oilseed rape fields

Abstract: The susceptibility of eleven local populations of Myzus persicae collected in Czech
oilseed rape fields in 2019-2021 to 10 insecticides was tested in a laboratory bioassay, and
the presence of the kdr (L1014F) mutation was proven by qPCR in samples from the
bioassay that survived treatment with alpha-cypermethrin. Resistance to alphacypermethrin and pirimicarb was proven in most of the tested populations. The mortality
of M. persicae ranged between 7.4 % and 98.4 % and between 10.7 % and 97.4 % after the
application of alpha-cypermethrin and pirimicarb at 100 % of the field application dose,
respectively. The L1014F mutation was detected in 44.5 % and 38.2 % of the M. persicae
individuals surviving the 100 % and 500 % doses of alpha-cypermethrin, respectively. The
frequency of alleles with the L1014F mutation in the samples of particular populations
ranged from 5 % to 45 %. The tested populations of M. persicae were highly susceptible
to chlorpyrifos-methyl, sulfoxaflor, flonicamid and spirotetramat.