Fungal spores. Coloured scanning electron micrograph (SEM) of unidentified fungal spores in a lemon grass leaf blade (Cymbopogon sp.). Some species of fungi are parasitic on plants, causing diseases that include rusts, smuts and mildews. The spores are the fungal reproductive bodies, which vary greatly in structure between fungi. The size and shape of the spores can often be used to identify the infecting fungus. Fungi are similar to plants in that they possess a cell wall and absorb nutrients in soluble form, but they lack chlorophyll and are therefore unable to photosynthesize. Magnification unknown.