Phytoplasma

Phytoplasma are specialised bacteria that are obligate parasites of plant phloem tissue and transmitting insects (vectors). They were first discovered by scientists in 1967 and were named mycoplasma-like organisms or MLOs. They cannot be cultured in vitro in cell-free media. They are characterised by their lack of a cell wall, a pleiomorphic or filamentous shape, normally with a diameter less than 1 micrometer, and their very small genomes.

Phytoplasmas are pathogens of agriculturally-important plants, including coconut, sugarcane, and sandalwood, causing a wide variety of symptoms that range from mild yellowing to death of infected plants. They are most prevalent in tropical and sub-tropical regions of the world. Phytoplasmas require a vector to be transmitted from plant to plant, and this normally takes the form of sap-sucking insects such as leaf hoppers, in which they are also able to survive and replicate.