Effects of copper and arsenic stress on the development of Norway spruce somatic embryos and their visualization with the environmental scanning electron microscope.

•Four cell lines of Norway spruce underwent the process of somatic embryogenesis under Cu(II) and As(V) stress.•Treatment with Cu(II) and As(V) resulted in morphological changes in early somatic embryos.•Abnormally developed somatic embryos were studied by transverse section and under environmental scanning electron microscope.•Microanalysis of effects of Cu(II) and As(V) showed both elements influenced macro and micronutrients uptake.