Asexual spores - (Zoospores). Spores produced by budding from the parent fungus without the addition of genetic material from another. Usually do not have a dormant phase.
Bacteria - A single celled organism which divides rapidly and grows in clumps or chains.
Fruiting body - the part of a fungus which grows out from the main structure to produce spores, eg. the orange-brown pustules of rust.
Hypha - individual strands of fungal growth. Protruding hyphae come together to produce spores which are carried away by the wind.
Microculture - a method of vegetative reproduction. A small piece of fast growing cells are taken from the shoot tip and grown in a special culture medium to produce an exact replica of the parent. (This is how Surfinia Petunias are grown as they arose from an abnormal shoot or 'sport'). Because a viral infection may not have migrated to these cells this can be a way of rescuing a rare plant or producing virus-free stock.
Mycelium - loose structure of a fungus made up of interconnected hyphae. Can extend over a large area underground.
Parasite - lives on a host taking food and support to the detriment of the host.
Pathogen - an organism which invades another causing it harm or leading to its death by extracting nutrients, damaging cells or producing toxic by-products.
Phloem - vessels which carry starch and sugars from the leaves down the plant, situated in the bark of trees and bushes.
Protoplasm - the mass of material which makes up the contents of a cell including enzymes and organised particles which carry out specific functions within the cell.
Saprophyte - describes most fungi which feed on dead material breaking down organic matter and are essential for good soil health.
Sexual spores - (Oospores). Produced when two hyphae come together and exchange genetic material. May form a protective coat and can lay dormant until favourable conditions return.
Xylem - vessels in the stem which carry water and nutrients up to the leaves.
Vector - means by which infection is transmitted.
Virus - Extremely small clumps of genetic material surrounded by protective proteins only visible at the high magnification of an electron microscope, appearing as rods or spheres. They enter the nucleus of the host cell and direct it to produce more viruses.
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