The occurrence and control of black bean aphid (Aphis fabae Scop.) in broad bean

To assess changes in the population of black bean aphid (Aphis fabae Scop.) in relation to the cultivar and timing of pest control using insecticides, precision field experiment was carried out in the fields of broad bean (Vicia faba L.).The research was conducted on three broad bean cultivars 'Tiffany', 'Fuego' and 'Vertigo' during three successive growing seasons in 2018, 2019 and 2020 at different sites with a distance between the experimental fields of 1-2 km.The experiment included five insect pest control regimes.The population of black bean aphid was monitored from the beginning of germination by using yellow traps and by counting percent of damaged plants.Assessments of black bean aphid's abundance were done at beginning of flowering to pod development stage.The infestation of black bean aphids on the plants of broad bean cultivars was affected by different spray regimes.All the tested broad bean cultivars were variably infested with Aphis fabae.The experimental data suggest that among the three cultivars tested the most susceptible to A. fabae was 'Tiffany', while 'Fuego' and 'Vertigo' supported a low population density of this pest.Insecticide application according to the local threshold resulted in a significantly lower aphid population compared to the untreated, and the efficacy was similar to that of the full control treatment.The data from four field trials obtained during the three growing seasons suggest that A. fabae infestation can incur a grain yield reduction of 0.21 t ha -1 .Applications according to local threshold with contact and systemic insecticides increased grain yield at the same level, and it was in line with the full control treatment.