PHYTOPLASMAS Meaning and
Definition
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Phytoplasmas are a type of microscopic, cell-wall-less bacteria that infect plants. They are classified under the class Mollicutes and belong to the group of bacteria known as Mycoplasma-like organisms (MLOs). Unlike most bacteria, phytoplasmas lack a rigid cell wall, making them difficult to classify within traditional bacterial taxonomies. Instead, they have a simplified cellular structure, consisting of a cell membrane surrounded by a plasma membrane.
These pathogens primarily infect phloem tissues of plants, which are responsible for transporting sugars and other nutrients throughout the plant. Phytoplasmas are transmitted from plant to plant through insect vectors such as leafhoppers, planthoppers, and psyllids, which acquire the bacteria by feeding on infected plants.
Infected plants exhibit various symptoms, depending on the host plant and the specific phytoplasma strain. These symptoms can include stunting, yellowing or reddening of leaves, witches' broom (excessive branching), phyllody (abnormal development of floral parts), and overall decline of plant health. The severity of symptoms can range from mild to severe, ultimately leading to reduced crop yield and economic losses in agricultural systems.
Phytoplasma diseases have a global distribution and affect a wide range of plant species, including important agricultural crops such as maize, rice, citrus fruits, and grapevines. Controlling phytoplasma infections is challenging, as they cannot be treated with antibiotics due to their lack of a cell wall. Instead, management strategies often involve preventing insect vectors from spreading the bacteria and removing infected plants to prevent further transmission.
Etymology of PHYTOPLASMAS
The word "phytoplasmas" is derived from two components: "phyto-" and "-plasmas".
1. "Phyto-": This prefix comes from the Greek word "phyton" which means "plant". It is commonly used in words related to plants, plant life, or plant biology. In the context of "phytoplasmas", "phyto-" refers to the fact that these microorganisms primarily affect plants.
2. "-Plasmas": The suffix "-plasmas" originates from the Greek word "plasma" which means "something molded or formed". In biology, it refers to a form or substance within a cell. In the case of "phytoplasmas", it implies that these microorganisms manifest as a particular form or substance within plant cells.
