Plant protection of ornamental indoor plants against fungal and bacterial diseases

Protection of ornamental pot crops from rots and wilting

Saintpaulia (African violet) is susceptible to a dangerous Phytophthora rot of stems and petioles, caused by the pathogen Phytophthora nicotianae var. parasitica. The disease manifests as tissue hardening, browning, and blackening; on leaves, it spreads in waves, quickly leading to the death of the entire plant. The main source of infection is usually the compost. To protect plants, use only clean, healthy compost and carry out timely fungicide applications (see page 353).

Powdery mildew (causative agent Oidium sp.) on Saintpaulia usually begins on flower sepals and rarely harms the leaves. Start treatments at the first symptoms of the disease — this will help reduce the amount of fungicide residues on the plants. The bacterium Corynebacterium fascians causes fasciation in Saintpaulia, but it usually does not cause serious harm. Much more dangerous is black leaf rot, caused by the bacterium Pseudomonas marginalis, which leads to mass plant death.

Upon the appearance of black leaf rot, it is necessary to completely replace or disinfect the substrate, as well as thoroughly disinfect propagation areas. On mature Saintpaulia leaves, a grey central spot may develop, causing the tip of the leaf blade to curl. The fungus Rhizopus stolonifer is found on diseased tissues, but its role as a primary pathogen has not yet been confirmed. Soft bacterial rot of stems and leaves (causative agent Erwinia carotovora var. carotovora) usually affects plants already weakened by the fungus Pythium splendens. Protective measures aimed at Pythium splendens are also effective against bacterial rot (see page 353).

Schizanthus is often affected by root and stem rots caused by pathogens Phytophthora sp., Pythium sp., and Rhizoctonia solani. The greatest danger is posed by Phytophthora foot and root rot. Among non-infectious pathologies of the crop, leaf tissue overgrowth, stunted growth, and chlorosis due to over-wetting of the compost stand out, as well as flower drop in the absence of pollination, which is the main problem during cultivation.

Sonerila suffers from foot and root rot caused by the fungus Rhizoctonia sp. The disease can be recognized by stunting, retarded growth, premature aging, and wilting of leaves. Streptocarpus is also sensitive to foot rot, the causative agent of which is the fungus Rhizoctonia solani.

Tradescantia is highly resistant and is rarely affected under extensive cultivation. Nevertheless, it can develop stem rot (causative agent Rhizoctonia solani) and root rot (causative agent Botrytis cinerea). For the Zantedeschia crop, specific diseases and control measures are not provided in the current section.

• Page with control measures — 353
• Size of Sclerotium rolfsii sclerotia — like a radish seed
• Main problem of Schizanthus — lack of pollination

This crop is grown for cut flowers and for planting in open soil. One of the most harmful diseases is bacterial root rot (causative agent Erwinia carotovora var. carotovora). Soft, wet rot develops on the roots of affected plants, and the leaves wilt. The only way to control the rot is to select young, healthy cuttings and propagate them in a disinfected substrate. Similar symptoms are produced by the fungus, applied during irrigation (see page 353). Moderate signs of mottling appear on the leaves as a result of infection with tomato spotted wilt virus tomato. Mosaic-affected plants must be destroyed. ZYGOCACTUS When affected by the fungus Fusarium oxysporum, stem rot appears, and the plant dies. The pathogen can live in the soil. The best way to control the disease is using healthy propagation material, disinfecting the compost, and in case of severe infection, irrigating with benzimidazole solutions. In addition, Pythium rots of the roots and root collar have been detected on Zygocactus. FURTHER READING Anon. (1969) Pot Plants. Bulletin 112. HMSO, London. Forsberg, J. L. (1975) Diseases of Ornamental Plants. University of Illinois Press, Urbana, IL. Van Nostrand Reinhold Company, New York. Mastalerz, J. W. (1971) Geraniums. Pennsylvania Flower Growers Association. Pirone, P. P. (1978) Diseases and Pests of Ornamental Plants. John Wiley and Sons, New York. Sinclair, W. A. (1966) How to Control Plant Disease in Home and Garden. Iowa State University Press, Ames Iowa. INDEX Ageratum 130 — agricultural practice 240 Azalea 348, 358 — Verticillium wilt 246 — leaf fasciation 359 — damping-off 245 Actipron 126 Bacteria 21 Aleyrospores 14, 65 — pathogenic 21 Alyssum 337, 346 — spread 68 Allergy 64 Marigold 337, 343 Allisan 129 — white rot of marigold 343 Aloe 348, 352 Begonia 337, 346, 348 Aliette 130 — tuber rot 359 Aminotriazines 38 — leaf spot 360 Anomalies, genetic 38 — bacterial wilt 371 Antagonists 266 Greenhouse whitefly 28, 116, 234 Antirrhinum 337, 340, 341, 343 Beloperone 348, 360 Anthraquinones 130 — leaf fasciation 360 Anthurium 348, 366 Benzimidazoles 127, 129 Pansy 337 Benlate 129 Apothecia 17 Benodanil 127, 129 Arum (Zantedeschia) 348, 380 Benomyl 117, 129 Asca 17 Bitertanol 129 Ascocarp 17 Blastomycetes 13 Ascospores 17 Diseases Aster 339 — control 75 Aubrieta 337 — pathogens 11 Aphelandra 348, 358 — diagnostics 40 — leaf spot 358 — environmental control 105 Afugan 129 — definition of term 11 Acervuli 19 — crop losses 60, 64 Acylalanines 129 — spread 62 Aerosols 125 Biological control 115, 117 Bavistin 129 Bupirimate 117, 129 Basidia 18 Witches' broom 27 Basidiomycetes 13, 18 Vertalec 115 Basidiospores 18 Vinclozolin 117, 129 Baycor 129 Viroids 23, 311, 313 Bayleton 129 Virulence 78 Eggplant 240 Viruses 23, 73

— non-persistent 23 — — — septoria leaf spot 284 — pathogenic 23 — bacterial stem cracking — persistent 25 282, 293 — helpers 27 — — of sepals 296 — propagative 25 — rust 283 — dissemination 26, 73 — top curling 297 — stylet-borne 23 — phyllody 296 — circulative 25 — bacterial wilt 293 Vitavax 129 — — slow 294 Relative air humidity — — phialophora 291 (RH) 105, 107 — — fusarium 288 Water — fusarium 282 — disinfection 112 Hemiascomycetes 13 — source of infection 68, 111 Hemibasidiomycetes 13 — spore dispersal 70 Virulence genes 78, 83 Waves of fruiting (champ.) 247 — resistance 79, 80 Survival of pathogens 65 Dahlia 337, 343 Carnation 277 —- white rot 343 — agricultural practice 277 Herbicides 36, 183, 237, 297 — leaf warty outgrowth 294 Occupational hygiene 109, 113 — latent carnation virus 295 Hydathodes 50, 59 — viral diseases 294 Hydroxypyrimidines 129 — basal rots 282 Hydroponics 101 — fusarium basal rot Gynura 348, 368

Hyphae 12 — — fusarium bud rot 286 Gloxinia 348, 368 — — leaf rot 985 Hydrangea 348, 370 — — shoot alternaria rot 283 — green petal 371 — — gray rot 283 — leaf spot ascochyta 370 — — — flower rot 986 — — ring spot (vir.) 370 — — rhizoctonia stem rot Pot crops 348

280 —- agricultural practice 348 — — black rot (alternaria) 279 — species 349 — anther smut 286 — root rots 352 — ring engraving 295 — — crown rots 352 — bacterial stunting 294 — rhizoctonia stem rot —- mottling 294 353 — — vein 295 —- — black root rot 354 — petal curling 297 — — brown root rot 355 — powdery mildew 288 —- — gray rot 356 — non-pathogenic disorders 295 — powdery mildew 356 — damage by herbicides 297 —- non-pathogenic proliferation 357 — — low temperatures 296 Pots — streaking (vir.) 295 — cleaning 113 — — oily 986 — source of infection 66 — — ring spot (fairy rings) Fungi

985 — biological control 115 — alternaria leaf spot — classification 13, 15

— virus vectors 74, 103 — polar 21

— growth in soil 70 Atmospheric pollution 35, 70

Dazomet 99 — mushroom caps 38, 272

Daconil 130 Legislative plant protection measures 114

Sulfur dioxide 110 Zantedeschia (arum) 348, 380

DD 99, 101 Chickweed 66, 231

Nitrogen deficiency 31, 46 Isoxazolones 130

— boron 32, 46, 297 Bed isolation 101, 104

— iron 31, 46 Imazalil 117, 129

— potassium 31, 46, 50 Ergosterol biosynthesis inhibitors

— magnesium 31, 46, 48 Inoculation 179

— manganese 31, 46, 48 Iprodione 117, 126, 129

— copper 46 Sources of infection primary 66,

— phosphorus 31, 46 Kalanchoe 348, 371

Dicarboximides 127, 129 Captan 117, 126, 130

Dinitro compounds 130 Carbendazim 117, 129

Dinocap 117, 130 Carboximides 128, 129

Dithane M-45 129 Carboxin 127, 129

Dithane w.p. 129 Quintozene 117, 126, 129

— bacterial stem rot 365 Disinfecting mats 112 365 Coleomycetes 13

— leaf spots 365 Collinia 348, 363

— bacterial leaf spot 364 — stem rot 363

— — brown leaf spot 365 Bellflower (Campanula) 348, 361

Sweet pea 342 — pathogens 86, 88

— root rot 342 — symptoms 52, 55, 56

Groundsel 212, 230, 234 — chemicals 96 Crop rotation 66, 87 Cucumber

— symptoms 48—51 — root rots 192

— functions 58 — — non-pathogenic root 193 Lobelia 337

Snapdragon 345 — — non-pathogenic crown 192 Maneb 117, 129

Mancozeb 117, 129 — white rot 197

Mineral oils 38, 271 — — rhizoctonia crown rot Copper 193

— preparations 130 — — phytophthora crown rot — sulfate 193 192

— oxychloride 130 — — black root rot (phomopsis) Mecoprop 183 189

Meristem culture 26, 77 — — mycosphaerella 196 Metalaxyl 129 — leaf deformation (herb.) 216 Methyl bromide 97 — — cotyledon 215 Methyl isothiocyanate 97, 98 — fracture 212

Milcurb 129 — hairy root 192 Mil-col 130 — mosaic (CMV) 208 Milfوران 129 — — green mottle 210 Mistral 129 — powdery mildew 201

Non-septate mycelium 12 — — downy (peronospora) 205 — septate 12 — uneven germination 213 Morestan 130 — fruit bleaching 212 Mutants 39, 127 — top burn 217

Nabam 117, 129 — downy mildew 205 Insect vectors 71 — gray mold 194

Physiological disorders 12, 30 — genetic yellowing 216 Nematodes 29 — seedling damping-off 187

— virus vectors 73, 181, 235, — brown spot 205

Nemesia 337, 344 — — angular bacterial 205 Nimrod 129 — leaf dissection 216 Nitroisophthalates 130 — rusty flowering 201 Nitrotal-isopropyl 117, 130 — verticillium wilt 208 Nuarimol 129 — — fusarium 206 Soil disinfestation 88 — fruit suppression 217

385. — cold drought 217 Pepper — cercospora leaf spot 203 — agricultural practice 240 Dandelion 212 — damping-off 245 Ozone 35 — root rots 241 Gram stain 21 — crown rots 241 Oxycarboxin 117, 129 — tobacco mosaic (TMV) 244 Honey fungus 71, 332, 367 — powdery mildew 243 Sprayers 121 — gray mold 242 — "Cheshunt" 123 Perithecia 17 — electrostatic 123 Petunia 337, 347 Dusting 126 — damping-off 340 Dusters 125 — leaf deformation 346 Sow thistle 212, 230 Picloram 182 Infection foci 42, 43 Pycnidia 18 Ferns 348, 367 Pycnospores 19 — leaf spots 367 Pilea 348, 377 Facultative parasites 12 Pyrazophos 117, 129 — obligate 11 Nutrient regime Paraquat 38 — deficiencies 46 Steam-air mixture 95 — disorders 31 Steam generators 125 — toxicity 47 Needle steam pipes 91 Plantvax 129 — combined 91 Plough, steam 91 — stationary 94 Ivy 348, 368 — Hoddesdon 90 — leaf and petiole rot 370 Shepherd's purse 212, 234 — bacterial leaf spot 368 Pastes 126 Surfactants 124 Patafol 129 Mechanical damage 35 Pathogens Rootstock 78, 83 — host interaction 61, Irrigation 64 — with sterilants 110 — survival 65 — with fungicides 100, 124, 125 — colonization 62 Soil — soil-borne 67 — drainage 94 — dispersal 74 — disinfestation 88, 96 — dissemination 68, 71, 73 — treatment with fungicides 100, 125 — growth in soil 71 — pathogens 85, 86 Pelargonium (geranium) 348, 371 — field capacity 96 — wet stem rot 371 — electrical heating 96 — alternaria leaf spot — steaming 90 375 — — surface 92 — rust 373 — loosening 94 — verticillium wilt 373 Grafting Pellionia 348, 353 — methods 84 Sodium pentachlorophenate 117 — rootstocks 83 Peperomia 348, 376 — resistance 78 Vectors 71, 73, 74 Primula 348, 378

Pathogens of decorative and greenhouse crops

In greenhouse cultivation, decorative crops often grow alongside transplant and vegetable plants, creating risks for rapid spread of mixed infections. Pathogens easily move from wild species or vegetables to houseplants, entering through stomata (section 50) or being transported by insects such as aphids—virus vectors (sections 23, 25). To protect plantings, it is important for an agronomist to monitor the phytosanitary status of all crops in the operation, taking into account the specifics of fungal mycelium development, rhizomorphs (section 18), sclerotial mass (section 249), and bacterial pathogens, including rickettsia (section 21). At the same time, it is necessary to control the dynamics of infection spread both on a crop-wide scale (section 41) and directly on individual plants (sections 46, 52, 54).

Many viral infections affect a wide range of hosts, which is why ornamental species can become infected from accompanying vegetable or weed crops. For example, cucumber mosaic virus (CMV) harms not only vegetables but also freesias, causing spotting on the flowers and leaf deformation. Tobacco necrosis, dandelion yellow mosaic, and arabis mosaic exhibit a similar cross-infectivity pattern, capable of spreading to indoor flowers. Aster yellows (mycoplasma), sugar beet western yellows, lettuce necrotic yellows, and pseudo-yellows also pose a particular danger.

Integrated protection system: disinfection, agronomic practices, and fungicides

Reliable disease prevention in greenhouses begins with substrate preparation and the maintenance of an optimal microclimate. Thermal methods are used to eliminate pathogens in peat, peat bags (sections 88, 102, 105), and reusable containers. Steaming is carried out via drains (section 94), under plastic film (section 93), or superficially (section 92), by treating the soil (section 77), seeds (sections 76, 77), and seedling boxes and pots (section 171). Alternatively, soil sterilants (section 96) and chemical disinfection with formaldehyde or formalin (sections 97, 100, 110) are used, performing fumigation with pure product, sulfur (section 110), or a mixture of formaldehyde with potassium permanganate (section 111).

1. Clear greenhouses of plant debris and eliminate waste piles near the greenhouses (sections 65, 67, 112).
2. Perform thermal treatment of the substrate (section 77) or steaming (sections 92, 93, 94).
3. Disinfect seeds to prevent the transmission of pathogens (sections 74, 76, 176) and maintain their biological functions (section 59) by means of seed treatment (sections 76, 159, 177).
4. Perform sterilization of seedling boxes, pots (section 171), and disinfection of structures.

When growing roses, freesias, and other flowers, it is critically important to control the physiological parameters of the environment that influence photosynthesis (section 58) and the accumulation of carbohydrates. The agronomist must prevent condensation from forming on leaves by monitoring the dew point (section 107) and regulating the irrigation regime (section 108), especially when using nutrient film technique (NFT) (section 103). The concentration of soluble salts in the substrate (sections 32, 49) directly affects plant susceptibility to diseases (section 33) and the speed of their spread (sections 42, 43), as do the pathways of infection spread via irrigation water (sections 69, 71). It is also important to monitor the accumulation of protective substances, such as phenols (section 38), which increase natural immunity.

• Spraying schedules — section 131
• Thermal soil treatment — section 77
• Seed steaming — sections 76, 77
• Dew point control — section 107
• Container sterilization — section 171

A wide arsenal of chemical agents is used to suppress fungal infections. Triadimefon, tri-minol, triforine, saprol, and fenpropimorph (section 129), as well as folpet and phaltan (section 130), are effective against rust and powdery mildew. Grey mold is controlled using procymidone, sumisclex, fubo, rhizo-lex (section 129), fungex and filex (section 130), as well as by fumigation with the product ronilan (sections 325, 329). For root rots and late blight, systemic active ingredients are used: propamocarb hydrochloride, prothiocarb (section 130), and fosetyl-aluminum (sections 117, 130). For foliar spraying and substrate irrigation (sections 100, 121, 124, 125), prochloraz, prochloraz-manganese, thiophanate-methyl, tecnazene, and fungaflor (sections 117, 129) are also applied.

Furalaxyl 129 — rust 361 Quinoxalines 130 — non-pathogenic wilting 361 inomethionate 1 Zinnia 344 itridiomycetes Chlamydospores 14 Cissus 348, 362 Sodium chlorate 38 Mushroom Chlorophytum 348, 361 — agricultural practice 247, 273 Copper oxychloride 117, 130 — Vert-de-gris 269 Chloropicrin 97, 101 — verticillium wilt 254 Chlorothalonil 117, 130 — viral diseases 263 Hoya 348, 353 — brown patch 269 Chrysanthemum — bacterial rot 261 — agricultural practice 299 — deformations 272 — aspermy (vir.) 315 — cap contamination 272 — seedlessness (vir.) 315 — Confetti 269 — inflorescence diseases 316 — red geotrichum 268 — wart disease 309 — La France (vir.) 263 — white rot 306 — false truffle 266 — — Phoma root rot 302 — shaggy stalk 257 — — petal (blight) 313 — mummification 262 — — ray blight 304 — open veil 271 — — stem rhizoctonia rot 303 — dieback (vir.) 263 — didymella 304 — cobweb disease 256 — fasciation 310 — yellow molds 269 — stunting (viroid) 311 — white (bubble) mold 24% — chlorotic spotting 313 — — — powdery 269 — powdery mildew 307 — — brown 270 — Non-pathogenic disorders 317 — — — powdery 270 — flower blight 313 — — green 270 — grey mold 305 — — red 268 — — flower 315 — — black hairy 270 — Septoria leaf spot — browning 263

309 — damage CO. 272 — bacterial cancer 309 — watery streak 263. — white rust 308 — cap spotting 259 39) — cockscomb (fasciation) Plant export 114 271 Elvaron 130 — stroma 271 Droplet electrostatic charging 124 — hardgill 271 Epinasties 51 — X-disease (vir.) 263 Epiphytotics — cephalosporiosis 259 — definition 65 — black cap 271 — development 68 — bacterial pitting 261 Ethylene 35 Schizanthus 348, 379 Etiology 11 Strains 78 Etridiazole 117, 126, 130, 133 — tolerant 126 Euparen 130 Oedema 50 Purple dead-nettle 66, 231 INDEX OF LATIN AND ENGLISH NAMES OF PEST ORGANISMS AND SOME PLANTS Aphanomyces sp. 349, 367 220, 242, 283, 286, 305, 315, 321, 343, Agaricus bisporus 247, 266 Erwinia lathyri 81, 220, 226, 362 Agave sp. 349, 352 Ascomycetes 14 Cisedapa X pertheopurpuria 349, 361 Agrobacterium tumefaciens 192 Callistephus chinensis 339 Agrobacterium rhizogenes 309, 333, 376 Campanula carpatia 144 Alternaria alternata 71, 343, 344, 375 Campanula isophylla 349, 361 Alternaria cucumerina 204 Capsella bursa-pastoris 212 Alternaria dauci 284 Celosia cristata var. pyramidalis 349, 362 Alternaria senecionis 362 Cercosporium sp. 258 Ampelomyces quisqualis 115 Cercospora melonis 203 Aphelandra squarrosa 349, 358 Cucumber green mottle mosaic virus 181, 235, 335 Aphanocladium album 259 Chaetomium globosum 268 Armillaria mellea 71, 332, 367 Chaetomium olivaceum 268 Ascomycetes 13 Chenopodium comosum var. variegatum 349, 361 Ascomycotina 13 Chlorophytum capense var. variegatum 349, 361 Ascomycetidae 13 Chrysanthemum chlorotic mottle virus 313 Aspermy virus 315 Chrysanthemum stunt viroid 311 Aspergillus niger 367 Chrysosporium luteum 269 Aster yellows virus 236 Chrysosporium sulfureum 269 Chrysomycetes 13 Cistus albidus 212

Basidiomycetes 13 C155 from tagetes 349, 356, 362 Basidiomycotina 13 Cephalosporium gregatum 256

, Cladosporium cucumerinum 206 Beet yellow mottle virus 234 Cladosporium echinulatum 285 Botrytis spp. 349, 359 Cladosporium pisum 115 Bougainvillea spp. 349, 360 Coelosporium tussilaginis 361 Blastomycetes 13 Colletotrichum coccodes 145 Bicana [musa] 270 Colletotrichum lagenarium 203 Botrytis cinerea 370 Colletotrichum trifolii 370

Colletotrichum trifolii 332 Hesi [fugata] 349, 367 Colletotrichum truncatum 307 Hesi [pumila] 349, 367 Coriptus [comus] 271 367 Coriptus [lineanus] 271 Eitua [versinallei] var. rufra 349, Cordyline terminalis 349, 363 353 Corynebacterium [flascans] 310, 346, Eucha [bolyana] 349, 368 360, 376, 379 Eucha [corynflora] 349, 368 Corynebacterium [misiopense] 158 Euitho [septica] 201 Corynespora [cassica] 358 Euma [doal] 76, 82, 127 Cuilophium [iseum] 349, 367 Fusarium [culmorum] 380, 282 Cucumis [uni] 208, 231 Fusarium [moniliforme] 319 Cucumis [umis] 2 210 Fusarium [oxysporum] 319, 381 Cucurbita [fitola] 207 Fusarium [oxysporum] f. sp. cucumerinum 206 Cucumber mosaic virus 1 208, 231 Fusarium [oxysporum] f. sp. lycopersici 171, Fusarium [sati] 145 Cyaten [persum] 349, 363 Fusarium [roseum] f. poae 286 Cyclocarpon [aestians] 342, 355 Dacia [sunicoa] 377 Dandelion yellow mosaic virus 234 Cybehelia [bacca] 362 Dautella [bryoiae] 196 Glomerella [crasae] 365 Dautella [chrysanthemi] 304 Cynura [scandens] 349, 368 f. p: [lycopersic] 147 Hareli 271 Glethiomyces [microsporis] 106, 266 Hedera [cananensis] 349, 368 Hienascha [exotica] 349, 364 Ascomycetes 13 Hedera [helix] 349, 368 Hedera [mactada] 349, 368 Pepocarpom [rosae] 329 Hemiascomycetes 13 Drocomyces [microsporis] 270 A. Hemiascomycetes 13 Domycetes [eromuss] 270, p =. Heterothella [dalehinensis] 285 Double virus streak of tomato 179 Heterosporium [echinulatum] 285 Dracaena [sandery] 349, 363 M Hoya [carnosa] 349, 353 Dracaena [terminalis] 349, 366 Hymenomycetes 13 Encarsia [formosa] 115 Hypomyces [roseulus] 256 Eruca [carodogra] var. [carodogra] 377, 379, 380 Hydrangea [notensis] 350, 370 Eruca [chrysanthemi] 294 Hydrangea [ring spot virus] 370 Erysiphe [cichoracearum] 299 Hydromyxomycetes 13 Erysiphe [polygona] 356, 371 Hyperomycetes [lactucae] 235 Hypnomycetes 14 Edhet [the virus of carnation] 295 Hypnomycetes 13 OB. Eup [ora] [pulcherima] 349, 377 Iceberg disease 303 Exobasidium [saccid] 359 Z: Peronsha [peremians] 313 Fasnegaera [dri] (Epasja [laportus] x Hedera [helix]) 349, 366 Leaf spot of carnation 295 Raa [laportus] 349, 367 Hesi [femina] 349, 367 Laboulbeniomycetes 13

La France 263 Phoma [chrysanthemi] 302 Langium [purpureum] 66 Phoma [destructia] 167 Leposphaelia [comolytum] 332 Phomopsis [serenodes] 71, 189, Phycomycetes 13 Macrophoma [dracontis] 366 Phyllostica [alminium] 345 Marssonina [panadpogana] 228 Phyllostica [nehelicola] 370 Mastigomycotina 13 Phytophthora [cryptobeda] 138 Melanium [locum] 286 Phytophthora [erythrosepica] 138 Microsphaera [pootica] 356 Phytophthora [medians] 165 Morcuereia [buger] 257 Phytophthora [mesasperma] 138 Phytophthora [nicotianae] var. [parasitophytophthora] [urea] 70, 138, 379 Mycogone [peritosa] 70, 249 Phytophthora [pumilae] 378 Mycospaherena [metomus] Phytophthora [spp.] 192, 193, 241, 340, Myrothecium [roudum] 337 342, 352 Myxomycotia 13 Phytophthora [verrucosa] 138 Myxomycetes 13 Phytostigmus [peremilis] 115 Myrus [ascoocus] 235 Pilea [cahert] var. [nana] 350, 377 Myrus [perscae] 230, 234, 295 Pleospora [herbarum] 229 Nasonoda [nuss-meeti] 230 Plicamia [thua] 270 349, 363 Primula [acaulis] 350, 378 Necta [rad] [nicola] 342, 355, 363, 368 Primula [genensis] 350, 378 Nicotiana [virus 1] 244 Primula [ofica] 350, 378 Primula [povanta] 350, 378 Olpidium [sp.] 288, 356, 379 Primula [stensis] 350, 378 Olpidium [brassicae] 74, 233 Prunus [necrotic ring spot virus] 335 Olpidium [chrysanthemi] 307 Pseudofalsanca [microspora] 266 Oidium [sp.] 192 Pseudomonas [aatic] 261 Oidium [brassicae] 74, 233 Pseudomonas [caryophylli] 282, 293 Oomycetes 13 Pseudomonas [cielori] 936, 261 Open well 271 Pseudomonas [corrugata] 109, 136 Osmatocerta [terrese] 270 Pseudomonas [fluorescens] 959 Papulaspora [byssa] 270 Pseudomonas [lachrymans] 205 Pearwostium [domestiscum] 350, 371 Pseudomonas [marginalis] 226, 236, Pearwostium [petium] 350, 371 379. o Pearwostium [ronde] 350, 371 Pseudomonas [syngpae] pv. [apri] 345. Pellioma [daleana] 350, 353 Pseudomonas [syngpae] pv. [tomato] 161.. Peperonia [hederaeoidia] 350, 376 Pseudomonas [tasi] 259, Peperonia [macnodia] 350, 376 Pseudoperonospora [cubensis] 205 Peronospora [parasitica] 346 Pseudoperonospora [pasa] 326 Peronospora [parsa] 316 Resohopeis [syndapana] 362, 378 Peronospora [radi] 396 Pseudo [yellows] 212, 234 Resga [osacoderma] 270 Pters [cretica] 350, 367 Phiophora [cinerescens] 291 Puccinia [chrysanthemi] 308