This is a glossary of some of the terms used in phytopathology

Phytopathology

Plant pathology is the scientific study of plant diseases caused by pathogens and environmental conditions . Organisms that cause infectious disease include fungi, oomycetes, bacteria, viruses, viroids, virus-like organisms, phytoplasmas, protozoa, nematodes and parasitic plants...

.

Phytopathology is the study of plant diseases. It is a multi-disciplinary since prerequisites for disease development are the presence of a susceptible host species, a pathogen and the appropriate environmental conditions. This is known as the disease triangle. Because of this interaction, the terminology used in phytopathology often comes from other disciplines including those dealing with the host species ( botany / plant science

Botany

Botany, plant science, or plant biology is a branch of biology that involves the scientific study of plant life. Traditionally, botany also included the study of fungi, algae and viruses...

, plant physiology

Plant physiology

Plant physiology is a subdiscipline of botany concerned with the functioning, or physiology, of plants. Closely related fields include plant morphology , plant ecology , phytochemistry , cell biology, and molecular biology.Fundamental processes such as photosynthesis, respiration, plant nutrition,...

), the pathogen (bacteriology

Bacteria

Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...

, mycology

Mycology

Mycology is the branch of biology concerned with the study of fungi, including their genetic and biochemical properties, their taxonomy and their use to humans as a source for tinder, medicinals , food and entheogens, as well as their dangers, such as poisoning or...

, nematology, virology

Virology

Virology is the study of viruses and virus-like agents: their structure, classification and evolution, their ways to infect and exploit cells for virus reproduction, the diseases they cause, the techniques to isolate and culture them, and their use in research and therapy...

), the environment and disease management practices (agronomy

Agronomy

Agronomy is the science and technology of producing and using plants for food, fuel, feed, fiber, and reclamation. Agronomy encompasses work in the areas of plant genetics, plant physiology, meteorology, and soil science. Agronomy is the application of a combination of sciences like biology,...

, soil science

Soil science

Soil science is the study of soil as a natural resource on the surface of the earth including soil formation, classification and mapping; physical, chemical, biological, and fertility properties of soils; and these properties in relation to the use and management of soils.Sometimes terms which...

, meteorology

Meteorology

Meteorology is the interdisciplinary scientific study of the atmosphere. Studies in the field stretch back millennia, though significant progress in meteorology did not occur until the 18th century. The 19th century saw breakthroughs occur after observing networks developed across several countries...

, environmental science

Environmental science

Environmental science is an interdisciplinary academic field that integrates physical and biological sciences, to the study of the environment, and the solution of environmental problems...

, ecology

Ecology

Ecology is the scientific study of the relations that living organisms have with respect to each other and their natural environment. Variables of interest to ecologists include the composition, distribution, amount , number, and changing states of organisms within and among ecosystems...

, plant breeding

Plant breeding

Plant breeding is the art and science of changing the genetics of plants in order to produce desired characteristics. Plant breeding can be accomplished through many different techniques ranging from simply selecting plants with desirable characteristics for propagation, to more complex molecular...

, pesticides, entomology

Entomology

Entomology is the scientific study of insects, a branch of arthropodology...

), and areas of study that apply to both the host and pathogen (molecular biology

Molecular biology

Molecular biology is the branch of biology that deals with the molecular basis of biological activity. This field overlaps with other areas of biology and chemistry, particularly genetics and biochemistry...

, genetics

Genetics

Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....

, molecular genetics

Molecular genetics

Molecular genetics is the field of biology and genetics that studies the structure and function of genes at a molecular level. The field studies how the genes are transferred from generation to generation. Molecular genetics employs the methods of genetics and molecular biology...

). The result is that most phytopathological glossary include terms from these other disciplines in addition to terms (disease incidence, horizontal resistance, gene-for-gene relationship, blast, scab and so on) that are specific to, or which have a unique meaning in phytopathology. This glossary is no exception. However, for the sake of brevity, it has for the most part, restricted terms from other disciplines to those that pertain to the pathogen. At some point, these terms should be moved to other glossaries (e.g. glossary of mycology, glossary of nematology, and so on).

A

abiotic

Disease not caused by living organisms

acceptable daily intake

acervulus (pl. acervuli)

The acervulus

Ascocarp

An ascocarp, or ascoma , is the fruiting body of an ascomycete fungus. It consists of very tightly interwoven hyphae and may contain millions of asci, each of which typically contains eight ascospores...

 is an erumpent, cushionlike fruiting body bearing conidiophores, conidia, and sometimes setae. It is distinguished from a stroma in not having a peridium or covering of fungal tissue of any kind.

acid precipitation

acid rain

acropetal

Actinomycetes

The Actinobacteria or Actinomycetes

Actinobacteria

Actinobacteria are a group of Gram-positive bacteria with high guanine and cytosine content. They can be terrestrial or aquatic. Actinobacteria is one of the dominant phyla of the bacteria....

 are a group of Gram-positive bacteria.

acute

acute toxicity

aeciospore

aecium

aflatoxin

agar

aggressiveness

air pollution

alkaloids

allele

allelopathy

alternate host

alternative hosts

alternation of generations

amphid

amphigynous

amphimixis

amphimobile

anaerobic

anamorph (adj. anamorphic; syn. imperfect state)

anastomosis (pl. anastomoses)

anthracnoes

antibiotic

antibody

antigen

antiseptic

apothecium

The apothecium

Ascocarp

An ascocarp, or ascoma , is the fruiting body of an ascomycete fungus. It consists of very tightly interwoven hyphae and may contain millions of asci, each of which typically contains eight ascospores...

 is an open, cuplike, or saucer-shaped sexual fungal fruiting body (ascocarp

Ascocarp

An ascocarp, or ascoma , is the fruiting body of an ascomycete fungus. It consists of very tightly interwoven hyphae and may contain millions of asci, each of which typically contains eight ascospores...

) containing asci.

antiseptic

appressorium (pl. appressoria)

arbuscular mycorrhiza (abbr. AM; syn. endomycorrhiza)

arbuscule

ascocarp (syn. ascoma)

ascogenous

ascogonium (pl. ascogonia)

ascoma (pl. ascomata; syn. ascocarp)

Ascomycetes

asci

ascospore

ascostroma (pl. ascostromata)

ascus (pl. asci)

aseptate

asexual

asexual reproduction

atrophy

AUDPC (abbr. for Area Under Disease Progress Curve)

autotroph

avirulence (avr) gene

avirulent (syn. nonpathogenic)

axenic

autoecious

B

bacilliform

bacterial streaming

bactericide

bacteriocin

bacteriophage

bacterium (pl. bacteria)

bactericide

basal knob (syn. stylet knob)

basidiocarp (syn. basidioma)

Basidiomyctes

The Division Basidiomycota is a large taxon within the Kingdom Fungi that includes those species that produce spores in a club-shaped structure called a basidium.

basidiospore

basidium (pl. basidia)

basidiospore

basidium (pl. basidia; adj. basidial)

binary fission

binucleate

bioassay

biocide

biocontrol (syn. biological control)

biotic

A disease caused by a living organism

biotroph (syn. obligate parasite)

biotype

bitunicate

blasting

blight

blotch

breaking

broadcast application

brooming

brown rot (of wood)



burn

bursa

C

canker

capsid (syn. coat protein)

carcinogen

carrier

casting

causal agent

certification

cfu (abbr. for colony forming unit)

chemotaxis (syn. chemotropism)

chemotherapy

chlamydospore

chlamydospore

A chlamydospore

Chlamydospore

A Chlamydospore is the thick-walled big resting spore of several kinds of fungi. It is the life-stage which survives in unfavourable conditions, such as dry or hot seasons....

 is the thick-walled big resting spore of several kinds of fungi.

chlorosis

chronic toxicity

chytridiomycetes

circulative-propagative transmission (syn. propagative transmission)

circulative transmission (syn. persistent transmission)

cirrus

cleistothecium

clamp connection

clavate (or claviform)

coalesce

coat protein (syn. capsid)

coccus (pl. cocci)

coelomycetes

colonization

colony

colony forming unit (abbr. cfu)

compartmentalization

conidiogenesis

conidiogenous

conidioma (pl. conidiomata)

conidiophore

conidium (pl. conidia)

conjugation

conk

constitutive

contact fungicide (syn. protectant fungicide)

coremium (pl. coremia; syn. synnema)

cross-protection

crozier

cryptobiosis (hidden life)

curl

cyst

cytopathology

D

damping-off

days to harvest

decay

degree-day

demicyclic

deuteromycetes (syn. Fungi Imperfecti)

diagnostic

antigen

diploid

Diploid (2x) cells have two copies (homologs) of each chromosome, usually one from the mother and one from the father.

diapause

dieback (v. die back)

differential host (syn. differential cultivar)

differential medium

differentiation

dikaryon (adj. dikaryotic)

dilution plating

dilution streaking

dimorphic

direct penetration

Discomycetes

disease

disease cycle

disease incidence

disease progress curve

disease pyramid

disease severity

disease triangle

disinfect

disinfest

dispersal (syn. dissemination)

dissemination (syn. dispersal)

dolipore septum

dormancy (adj. dormant)

downy mildew

drift (of pesticides)

drought

durable resistance

dwarfing

E

echinulate

economic threshold

ectomycorrhiza (pl. ectomycorrhizae)

ectoparasite

ectotrophic

elicitor

enation

encapsidate

encyst

endemic

endogenous

endophytic

endoconidium (pl. endoconidia)

endomycorrhiza (pl. endomycorrhizae; syn. arbuscular mycorrhiza)

endoparasite

endospore

epidemic

epidemiology

epinasty

epiphytotic

The epidemic condition of a disease, in a plant population. Compare with enphytotic

eradicant

eradication

ergot

ergotism

erumpent

escape

etiolation

etiology

exclusion

exogenous

exudate

F

f. sp. (abbr. for forma specialis)

facultative parasite

facultative saprotroph

fasciation

fastidious

filamentous (syn. filiform)

flagellum

flagging

fleck

focus (pl. foci)

forest decline

forma specialis (abbr. f.sp.; pl. formae speciales)

fructification

fruiting body

fumigant (v. fumigate)

Fungi Imperfecti (syn. Deuteromycetes

fungicide (adj. fungicidal)

Chemical designed to kill fungi

fungus (pl. fungi)

fungistat (adj. fungistatic)

Inhibits growth of some fungi.

fungistasis

fusiform

G

gall

gametangium (pl. gametangia)

gametophyte

gene-for-gene hypothesis

general resistance (syn. horizontal resistance, race non-specific resistance)

genotype

germ theory

giant cell

girdle

giant cells

gram-negative

Gram-negative

Gram-negative

Gram-negative bacteria are bacteria that do not retain crystal violet dye in the Gram staining protocol. In a Gram stain test, a counterstain is added after the crystal violet, coloring all Gram-negative bacteria with a red or pink color...

 bacteria are those that do not retain crystal violet dye in the Gram staining protocol.

gram-positive

Gram-positive

Gram-positive

Gram-positive bacteria are those that are stained dark blue or violet by Gram staining. This is in contrast to Gram-negative bacteria, which cannot retain the crystal violet stain, instead taking up the counterstain and appearing red or pink...

 bacteria are classified as bacteria that retain a crystal violet dye during the Gram stain process.

gram stain

growth regulator (syn. hormone)

gummosis (pl. gummoses)

H

haploid

hardiness

haustorium (pl. haustoria)

The haustorium

Haustorium

In botany, a haustorium is the appendage or portion of a parasitic fungus or of the root of a parasitic plant that penetrates the host's tissue and draws nutrients from it. Haustoria do not penetrate the host's cell membranes.Fungi in all major divisions form haustoria...

 is the hyphal tip of a parasitic fungus

hemiparasite

hermaphrodite (adj. hermaphroditic)

heteroecious

heterokaryon

Heterokaryon

A heterokaryon is a cell that contains multiple, genetically different nuclei. This can occur naturally, such as in the mycelium of fungi during sexual reproduction, or artificially as formed by the experimental fusion of two genetically different cells. A medical example is a heterokaryon composed...

 (adj. heterokaryotic

Heterokaryotic

Heterokaryotic refers to cells where two or more genetically different nuclei share one common cytoplasm. It is the antonym of homokaryotic. This stage after Plasmogamy, the fusion of the cytoplasm,a and before Karyogamy, the fusion of the nuclei. It is neither 1n or 2n. It is in the sexual...

)

heterothallic

heterotroph

holomorph

holoparasite

homokaryon (adj. homokaryotic

Homokaryotic

Homokaryotic refers to multinucleate cells where all nuclei are genetically identical. It is the antonym of heterokaryotic....

)

homothallism (adj. homothallic)

horizontal resistance (syn. general resistance, race non-specific resistance)

host plant

host range

hyaline

hymenium

hyperparasite

hyperplasia

hypertrophy

hypersensitive

hypersensitive reaction and pathogenicity (hrp) gene

hypersensitive response (HR)

hypha

hyphal sheath (syn. mantle)

hyphomycetes

hyphopodium

hypoplasia

hypovirulence

hypovirulence is reduced virulence of a pathogen. Hypovirulence in fungi can be caused by a virus within the fungus. The virus reduces virulence and sporulation. A hypovirus-fungus can be used in biological control.

I

immune
immunity
imperfect fungi (syn. Fungi Imperfecti, deuteromycetes)
imperfect state (syn. anamorph)
in planta
in situ
in vitro
in vivo
incubation period
indicator plant
indirect penetration
induced
induced systemic resistance (ISR)
infection court
infection cushion
infection focus
infection peg (syn. penetration peg)
infection period
infectious
infective
infest (n. infestation)
initial inoculum (syn. primary inoculum)
injury
inoculate (n. inoculation)
inoculum (pl. inocula)
inoculum density
integrated pest management (abbr. IPM)
intumescence (syn. edema or oedema)
IPM (abbr. for integrated pest management)
isolate

K

klendusity
The disease-escaping ability of plants.
Koch's postulates
knot

L

latent infection
latent period
leaf dip
leaf spot
leafroll
lesion
life cycle
lignification
local lesion
local necrosis
lodge

M

macerate
macroconidium (pl. macroconidia)
macrocyclic
macronutrient
mantle (syn. hyphal sheath)
mating types
mechanical injury
mechanical transmission
medium (pl. media)
melanin
microbial
microclimate
microconidium (pl. microconidia)
microcyclic
microflora
micronutrient
microorganism (syn. microbe)
microsclerotium
mildew
MLO (syn. mycoplasmalike organism)
mold
mollicute
monocyclic
monoecious
monogenic
monogenic resistance (syn. single gene resistance)
monotrichous
monoxenic culture
mosaic
motile
mottle
movement protein
multigenic resistance (syn. polygenic resistance)
multiline
multinucleate
multiparticulate virus
multipartite virus
multiseptate
mummification
mummy
mushroom
mutagen
Mycelia sterilia
mycelium (pl. mycelia)

Mycelium

Mycelium

thumb|right|Fungal myceliaMycelium is the vegetative part of a fungus, consisting of a mass of branching, thread-like hyphae. The mass of hyphae is sometimes called shiro, especially within the fairy ring fungi. Fungal colonies composed of mycelia are found in soil and on or within many other...

 is the vegetative part of a fungus consisting of a mass of branching, threadlike hyphae that exists below the ground or within another substrate.

mycology
mycoparasite
mycoplasmalike organism (syn. MLO)
mycorrhiza (pl. mycorrhizae; adj. mycorrhizal)
mycotoxin
mycovirus
Myxomycetes (syn. slime molds)

N

necrosis (adj. necrotic)
necrotroph
needle cast (of conifers)
nematicide

A nematicide

Nematicide

A nematicide is a type of chemical pesticide used to kill parasitic nematodes.One common nematicide is obtained from neem cake, the residue obtained after cold-pressing the fruit and kernels of the neem tree. Known by several names in the world, the tree was first cultivated in India in ancient...

 is a type of chemical pesticide used to kill parasitic nematodes.

nematode

Nematodes are unsegmented, bilaterally symmetric and triploblastic protostomes with a complete digestive system.

nitrogen oxides
noninfectious disease
nonpathogenic (syn. avirulent)
nonpersistent transmission (syn. stylet-borne transmission)
nonseptate

O

obligate parasite (syn. biotroph)
occlusion
oedema (also edema; syn. intumescence)
oligogenic resistance
oogonium (pl. oogonia)

An oogonium

Oogonium

"Oogonium" may refer to either a primordial oocyte in a female fetus or the female gametangium of certain thallophytes.-in the fetus:Oogonia are formed in large numbers by mitosis early in fetal development from primordial germ cells...

 is a female gametogonium.

oomycetes (adj. oomycetous)
oospore
ooze
ostiole (adj. ostiolate)
overwinter

P

pandemic
papilla
paragynous
parasexualism
parasite (adj. parasitic)
parasitism
parthenogenesis (adj. parthenogenetic)
partial resistance
pasteurization
pathogen (adj. pathogenic)
pathogenesis-related (PR) proteins
pathogenicity
pathology
pathotype
pathovar (abbr. pv.)
penetration
penetration peg (syn. infection peg)
perfect (see teleomorph)
perithecium (pl. perithecia)
peritrichate
persistent transmission (syn. circulative transmission)
pest
pesticide
phenological synchrony
phenotype
phloem necrosis
Phycomycete
phyllody
phylloplane-competent
physiogenic disease
phytoalexin
phytopathogenic
phytopathology (syn. plant pathology)
phytoplasma (syn. mycoplasmalike organism, MLO)
phytosanitary certificate
phytotoxic
plant pathology (syn. phytopathology)
plasmodiophoromycetes
plasmodium (pl. plasmodia)
polycyclic
polyetic
polygenic resistance (syn. multigenic resistance)
polymorphism
polyprotein
powdery mildew
predispose (n. predisposition)

primary inoculum (syn. initial inoculum)
proinhibitin
prokaryote
promycelium (pl. promycelia)
propagative transmission (syn. circulative propagative transmission)
propagule
protectant
protectant fungicide (syn. contact fungicide)
pseudothecium (pl. pseudothecia)
Puccinia pathway
pustule
pv. (abbr. for pathovar)
pycnidiospore
pycnium (pl. pycnia; syn. spermagonium)

Q

qualitative resistance
quantitative resistance
quarantine
quiescent
quiescent
dormant or inactive
quorum sensing

R

race
race non-specific resistance (syn. general resistance, horizontal resistance)
receptive hypha
reniform
resinosis
resistant (n. resistance)
rhizomorph
rhizosphere
rhizosphere-competent
ringspot
rosette
rot
roundworm
rugose
russet
rust

S

sanitation
sap transmission
saprobe (syn. saprotroph)
saprotroph

A saprotroph (or saprobe) is an organism that obtains its nutrients from non-living organic matter, usually dead and decaying plant or animal matter, by absorbing soluble organic compounds.

scab
scald
sclerenchyma (adj. sclerenchymatous)
sclerotium (pl. sclerotia)

A sclerotium

Sclerotium

A sclerotium is a compact mass of hardened fungal mycelium containing food reserves. One role of sclerotia is to survive environmental extremes. In some higher fungi such as ergot, sclerotia become detached and remain dormant until a favorable opportunity for growth. Other fungi that produce...

 is a compact mass of hardened mycelium (as an ergot) stored with reserve food material that in some higher fungi becomes detached and remains dormant until a favorable opportunity for growth occurs.

scorch
secondary infection
secondary inoculum
secondary metabolite
secondary organism
seed treatment
seedborne
selective medium
septate
serrate
sessile
seta (pl. setae)


sexual spore
sexually compatible
shot-hole
sign
single gene resistance (syn. monogenic resistance)
slime molds (syn. Myxomycetes)
smut
soft rot
soil drench
soilborne
soil pasteurization
soil sterilization
solarization
sooty mold
sorus (pl. sori)
sp. (abbr. for species; pl. spp.)
species
specific resistance (syn. vertical resistance)
spermagonium (pl. spermagonia; syn. pycnium for rust fungi)
spermatium (pl. spermatia; syn. pycniospore for rust fungi)
spicule

spiroplasma - helical, motile, cell wall-less bacterium; member of genus Spiroplasma in class Mollicutes
sporangiophore
sporangiospore
sporangium (pl. sporangia)
spore
sporidium (pl.sporidia)
sporocarp
spore-bearing fruiting body
sporodochium (pl.sporodochia)
sporogenous
sporophore
sporophyte
sporulate
spot
stabilizing selection
staghead
stem pitting
sterigma

Sterigma

thumb|right|The sterigmata is the slender extension that connects the spore to the basidia .A sterigma is an extension of the basidium consisting of a basal filamentous part and a slender projection with a spore at the tip...

 (pl. sterigmata)
sterilant
sterile fungus
sterilization (adj. sterilized)
stippling
strain

streak
striate (n. striations)
stroma (pl. stromata)
stunting
stylet knob (syn. basal knob)
stylet-borne transmission (syn. nonpersistent

transmission)
subspecies
substrate
sunscald or sunburn
suppressive soil
susceptible (n. susceptibility)
symptom
symptomless carrier
syncytium (pl. syncytia)
synergism (adj. synergistic)
synnema (pl. synnemata; syn. coremium)
systematics
systemic
systemic acquired resistance (SAR)
systemic fungicide

T

teleomorph (syn. perfect state)
teliospore (sometimes called teleutospore, teleutosporodesm)

Teliospore

Teliospore

Teliospore is the thick-walled resting spore of some fungi , from which the basidium arises.-Development:They develop in telia ....

 (sometimes called teleutospore) is the thick-walled resting spore of some fungi (rusts and smuts), from which the basidium arises.

telium (pl. telia)
temporary wilt
thallus
thermotherapy
tolerance (adj. tolerant)
toxicity
toxin
transmit (n. transmission)
trap crop
transmit (n. transmission)
trenching
tumor (syn. gall)
type

U

urediniospore (also urediospore, uredospore)
uredinium (also uredium; pl. uredinia)

V

vascular wilt disease
vector
vein banding
vein clearing
vermiform
vertical resistance (syn. specific resistance)
viable (n. viability)
virescence
virion
viroid
viroplasm
virulence
virulent
viruliferous
virus-laden, usually applied to insects or nematodes as vectors
virus

A virus

Virus

A virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea...

 is a microscopic particle (ranging in size from 20 - 300 nm) that can infect the cells of a biological organism.

viscin

W

walling-off
water-soaked
white rot (of wood)
white rust
wild type
wilt
winterburn
witches' broom
wound

X

XLB (xylem-limited fastidious bacteria)
xylem-limited fastidious bacteria (XLB)

Y

yellowing

yellows

Z

zonate
zoosporangium
zoospore

A zoospore

Zoospore

A zoospore is a motile asexual spore that uses a flagellum for locomotion. Also called a swarm spore, these spores are created by some algae, bacteria and fungi to propagate themselves.-Flagella:...

 is a motile asexual spore utilizing a flagellum for locomotion.

Zygomycetes
zygospore

A zygospore

Zygospore

A zygospore is a diploid reproductive stage in the life cycle of many fungi and protists. Zygospores are created by the nuclear fusion of haploid cells. In fungi, zygospores are termed chlamydospores and are formed after the fusion of hyphae of different mating types...

is a sexual part of a fungus, a chlamydospore that is created by the nuclear fusion of haploid hyphae of different mating types.