Resting Spore

a thick-walled spore, usually formed by a sexual process, that germinates after remaining in a dormant state for an extended period of time.

Rot

the disintegration of tissue, often caused by enzyme or toxins produced by pathogens.
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Rust

rust-coloured pustules formed by members of the Uredinales (rust fungi).
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S

Saprophyte

an organism that obtains nourishment from non-living organic matter (usually dead and decaying plant or animal matter) by absorbing soluble organic compounds.

Scab

a discrete, superficial roughened lesion.
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Sclerotium (pl. Sclerotia)

a hard, resistant vegetative resting body of a fungus composed of a compact mass of hyphae and capable of surviving under unfavourable environmental conditions. Under favourable conditions the sclerotium can produces sexual or asexual fruiting bodies.

Secondary Inoculum

inoculum produced by infections that took place during the same growing season. Compare with primary inoculum.

Secondary Metabolite

a compound that is not necessary for growth or maintenance of cellular functions but is, in general, synthesised for the protection of a cell or microorganism during the stationary phase of its growth cycle. In plants, secondary metabolites are believed to be important in the attraction of pollinators and to have a function in defense, as some metabolites have antimicrobial properties. Also known as secondary products.

Smut

a disease characterised by black spore masses on leaves, stems or inflorescences, caused by members of the Ustilaginales (smut fungi).
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Sporangiophore

sporangium -bearing body of a fungus.

Sporangium (pl. Sporangia)

a unicellular or multicellular sac-like structure in fungi that produces asexual spores.

Spore

a specialised reproductive body in fungi (and some other organisms), containing one or more cells, capable of developing into an adult.

Stoma (pl. Stomata)

a minute opening in the epidermis of leaves and stems through which gasses pass. The stoma is bordered by two guard cells which open and close depending on their turgidity. The term stoma is often used to refer to the entire stomatal apparatus i.e. the guard cells as well as the pore they surround.

Systemic

(1) pertaining to a disease in which the pathogen spreads generally throughout the plant; (2) pertaining to a chemical absorbed into the plant through root or foliage and transported internally throughout the plant.
- Systemic fungicide: a chemical agent that spreads internally through the plant and eradicates established fungal infections. See fungicide.

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T

Tillage

the process of turning or mixing the soil.

Toxin

in general, a poisonous substance of biological origin. Specifically, a compound produced by a microorganism which is toxic to other organisms.

Transcription

the process whereby a base sequence of messenger RNA (mRNA) is synthesized on a complementary segment of DNA.

Translation

the process that occurs at the ribosome whereby the information in messenger RNA (mRNA) is used to assemble amino acids into a protein.

Дата добавления: 2015-10-31