This is a glossary of some of the terms used in phytopathology. Phytopathology is the study of plant diseases. It is a multi-disciplinary science 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, plant physiology), the pathogen (bacteriology, mycology, nematology, virology), the environment and disease management practices (agronomy, soil science, meteorology, environmental science, ecology, plant breeding, pesticides, entomology), and areas of study that apply to both the host and pathogen (molecular biology, genetics, molecular genetics). 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 ** ** acceptable daily intake ** ** acervulus (pl. acervuli) ** ** acid precipitation ** ** acid rain ** ** acropetal ** ** Actinomycetes ** ** 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 ** ** 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 ** ** basidiospore ** ** basidium (pl. basidia) ** ** basidiospore ** ** basidium (pl. basidia; adj. basidial) ** ** binary fission ** ** binucleate ** ** bioassay ** ** biocide ** ** biocontrol (syn. biological control) ** ** biotic ** ** biotroph (syn. obligate parasite) ** ** biotype ** ** bitunicate ** ** blasting ** ** blight ** ** blotch ** ** breaking ** ** broadcast application ** ** brooming ** ** brown rot (of wood) **

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** 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 ** ** 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 ** **<span id="contact fungicide (syn. protectant fungicide)" style="font-weight: bold">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 ** ** 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 ** ** 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 ** **<span id="fumigant (v. fumigate)" style="font-weight: bold">fumigant (v. fumigate) ** ** Fungi Imperfecti (syn. Deuteromycetes ** ** fungicide (adj. fungicidal) ** ** fungus (pl. fungi) ** ** fungistat (adj. fungistatic) ** ** 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-positive ** ** gram stain ** ** growth regulator (syn. hormone) ** ** gummosis (pl. gummoses) **

H

** haploid ** ** hardiness ** ** haustorium (pl. haustoria) ** ** hemiparasite ** ** hermaphrodite (adj. hermaphroditic) ** ** heteroecious ** ** heterokaryon (adj. heterokaryotic) ** ** heterothallic ** ** heterotroph ** ** holomorph ** ** holoparasite ** ** homokaryon (adj. homokaryotic) ** ** 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 **

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 ** **<span id="infest (n. infestation) " style="font-weight: bold">infest (n. infestation) ** ** initial inoculum (syn. primary inoculum) ** ** injury ** ** inoculate (n. inoculation) ** ** inoculum (pl. inocula) ** ** inoculum density ** ** integrated pest management (abbr. IPM) ** **<span id="intumescence (syn. edema or oedema) " style="font-weight: bold">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 ** **<span id="MLO (syn. mycoplasmalike organsim) " style="font-weight: bold">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) ** ** 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 ** ** nematode ** ** 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) ** ** 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) **

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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 ** **<span id="resistant (n. resistance) " style="font-weight: bold">resistant (n. resistance) ** ** rhizomorph ** ** rhizosphere ** ** rhizosphere-competent ** ** ringspot ** ** rosette ** ** rot ** ** roundworm ** ** rugose ** ** russet ** ** rust **

S

** sanitation ** ** sap transmission ** **<span id="saprobe (syn. [saprotroph](https://bliptext.com/articles/saprotroph))" style="font-weight: bold">saprobe (syn. saprotroph) ** ** saprotroph ** ** scab ** ** scald ** ** sclerenchyma (adj. sclerenchymatous) ** ** sclerotium (pl. sclerotia) ** ** scorch ** ** secondary infection ** ** secondary inoculum ** ** secondary metabolite ** ** secondary organism ** ** seed treatment ** ** seedborne ** ** selective medium ** ** septate ** ** serrate ** ** sessile ** ** seta (pl. setae) **

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** 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 (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 ** **<span id="susceptible (n. susceptibility)" style="font-weight: bold">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) ** ** telium (pl. telia) ** ** temporary wilt ** ** thallus ** ** thermotherapy ** **<span id="tolerance (adj. tolerant) " style="font-weight: bold">tolerance (adj. tolerant) ** ** toxicity ** ** toxin ** ** transmit (n. transmission) ** ** trap crop ** ** transmit (n. transmission) ** ** trenching ** **<span id="tumor (syn. gall)" style="font-weight: bold">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 ** ** viscin **

W

** walling-off ** ** water-soaked ** **<span id="white rot (of wood)" style="font-weight: bold">white rot (of wood) ** ** white rust ** ** wild type ** ** wilt ** ** winterburn ** ** witches' broom ** ** wound **

X

**<span id="XLB (xylem-limited fastidious bacteria)" style="font-weight: bold">XLB (xylem-limited fastidious bacteria) ** **<span id="xylem-limited fastidious bacteria (XLB)" style="font-weight: bold">xylem-limited fastidious bacteria (XLB) **

Y

** yellowing ** ** yellows **

Z

** zonate ** ** zoosporangium ** ** zoospore ** ** Zygomycetes ** ** zygospore **