Plants are the primary means by which food is produced for living organisms. These include the species Homo sapiens – all 7 billion plus of us. But we are far from being the only species that depends on plants. There are many herbivores with which we compete, some of the most devastating being insects. Moreover, plants deemed useful as sources of food may be outcompeted by other plants of less practical use: these are often regarded as weeds. More insidiously, there are many infectious agents ranging from viroids, consisting of a few hundred nucleotides, through viruses, bacteria, mycoplasmas, nematodes and fungi to plants themselves that parasitise those crop plants we use as sources of food.
The tale of a tiny worm, the bacteria that live inside her, and a tree being munched on by a grub.