Norway spruce somatic embryos (first week of maturation)

Norway spruce somatic embryos after the 1^st week of maturation - small meristematic cells of the embryo "head" are clearly distinguishable from the elongated cells of suspensor.

Cell walls were stained with fluorescent dye Calcofluor White, which binds to polysaccharides as cellulose and chitin. Images were acquired after UV excitation as maximum intensity projections of optical slices using confocal laser scanning microscope.