病虫害防治--欧洲植物保护联盟

 EPPO Standards  Guidelines on good plant protection practice Umbelliferous crops PP 2/22(1) English European and Mediterranean Plant Protection Organization 1, rue Le Nôtre, 75016 Paris, France 2000 approval EPPO Standards are approved by EPPO Council. The date of approval appears in each individual standard. Review EPPO Standards are subject to periodic review and amendment. The next review date for this set of EPPO Standards is decided by the EPPO Working Party on Plant Protection Products. Amendment record Amendments will be issued as necessary, numbered and dated. The dates of amendment appear in each individual standard (as appropriate). Distribution EPPO Standards are distributed by the EPPO Secretariat to all EPPO Member Governments. Copies are available to any interested person under particular conditions upon request to the EPPO Secretariat. Scope EPPO guidelines on good plant protection practice (GPP) are intended to be used by National Plant Protection Organizations, in their capacity as authorities responsible for regulation of, and advisory services related to, the use of plant protection products. References All EPPO guidelines on good plant protection practice refer to the following general guideline: OEPP/EPPO (1994) EPPO Standard PP 2/1(1) Guideline on good plant protection practice: principles of good plant protection practice. Bulletin OEPP/EPPO Bulletin 24, 233-240. outline of requirements For each major crop of the EPPO region, EPPO guidelines on good plant protection practice (GPP) cover methods for controlling pests (including pathogens and weeds). The main pests of the crop in all parts of the EPPO region are considered. For each, details are given on biology and development, appropriate control strategies are described, and, if relevant, examples of active substances which can be used for chemical control are mentioned. European and Mediterranean Plant Protection Organization Organisation Européenne et Méditerrannéenne pour la Protection des Plantes PP 2/22(1) English Guidelines on good plant protection practice Umbelliferous crops Specific scope Specific approval and amendment This standard describes good plant protection practice for umbelliferous crops. First approved in September 2000. ____________________ This guideline on GPP for umbelliferous crops forms part of an EPPO programme to prepare such guidelines for all major crops of the EPPO region. It should be read in conjunction with EPPO Standard PP 2/1 Principles of Good plant protection Practice. The guideline covers methods for controlling pests (including pathogens and weeds) of crops of the family Apiaceae (i.e. umbelliferous crops). The main umbelliferous crops are vegetables: carrot (Daucus carota), celery (Apium graveolens), celeriac (A. graveolens var. rapaceum), fennel (Foeniculum vulgare var. dulce) and parsnip (Pastinaca sativa). They are biennials grown for the swollen roots or leaf bases formed at the end of the first growing season. Umbellifers are also grown as herbs, such as parsley (Petroselinum crispum), coriander (Coriandrum sativum) and caraway (Carum carvi). Soil-borne pests and diseases are especially important. Crops should be grown in soils which are, as far possible, free from soil-borne pests. The basis of GPP in umbelliferous crops is adequate rotation and good waste-handling practices. Waste from processing or packing operations should not be returned to the soil or at least returned to the same field from which it was produced. Treatments can be applied to the seeds as well as the soil and aerial parts of the crop and, where relevant, seed treatment is to be preferred. Growing crops should be monitored (soil sampled for nematodes before sowing) for the need for pest, disease and weed control treatments in conjunction with trapping, baiting and forecasting systems where available and proved effective. Treatments should then be applied following a risk assessment of the potential for economic damage. Some soil-borne diseases are only seen after harvest, and the risk assessment is based on previous history of the field. The principal pests of umbelliferous crops considered are given in Table 1. Explanatory note on active substances The EPPO Panel on Good Plant Protection Practice, in preparing this guideline, considered information on specific active substances used in plant protection products and how these relate to the basic GPP strategy. These details on active substances are included if backed by information on registered products in several EPPO countries. They thus represent current GPP at least in those countries. It is possible that, for any of numerous reasons, these active substances are not registered for that use, or are restricted, in other EPPO countries. This does not invalidate the basic strategy. EPPO recommends that, to follow the principles of GPP, only products registered in a country for a given purpose should be used. CARROT Carrots (Daucus carota subsp. sativa) are the main umbelliferous crop in most European countries. They are grown from seed outdoors through spring and summer. Carrots have to be grown on good fertile soils to ensure even growth of the roots. Pythium violae and Pythium sulcatum (cavity spot) General First symptoms are slightly sunken elliptical lesions on the root surface beneath which can be found a cavity. Subsequently, the surface tissue breaks down exposing the cavity. The cavities finally become raised greyish areas. Cavity spot occurs especially on soils with poor drainage or structure. Secondary pathogens, including other Pythium spp., cause further rotting which can affect most of the root. All carrot crops are potentially susceptible. The least risk is with early harvested main crops, and the most risk with over-wintered field-stored crops. The number and size of lesions is very variable. Under high disease pressure, these Pythium spp. can cause damage to fine roots and subsequent branching of the main root. Pythium violae is thought to colonize roots at the seedling stage from soil-borne resting spores but symptoms only start to appear about 12 weeks after sowing. The rapid appearance of symptoms suggests that there may be discrete infection periods but interactions with weather factors are poorly understood. Table 1 Principal pests of umbelliferous crops considered Pests Crops on which economic damage occurs Pythium violae, P. sulcatum (cavity spot) carrot, parsnip Pythium spp., Thanatephorus cucumeris (damping off) celery, celeriac Helicobasidium purpureum (violet root rot) carrot, parsnip, fennel Phytophthora primulae (root and crown rot) parsley Phytophthora syringae (leaf blight) fennel Erysiphe heraclei (powdery mildew) carrot, parsnip, fennel Oidium sp (powdery mildew) parsley, herbs Plasmopara nivea (downy mildew) parsnip, fennel Peronospora sp. (downy mildew) parsley Alternaria dauci (alternaria blight) carrot, parsley Botryotinia fuckeliana (grey mould) carrot, celery, celeriac, herbs Cercosporidium punctum fennel Phomopsis foeniculi fennel Ramularia coriandri (leaf spot) coriander Septoria apiicola (leaf spot) celery, celeriac Septoria petroselini ( leaf spot) parsley Alternaria radicina (black rot) carrot, celery, celeriac, parsley Thielaviopsis basicola carrot Itersonilia pastinacae (canker) parsnip Mycocentrospora acerina (liquorice rot) carrot, parsnip, celery, celeriac, caraway Phoma apiicola (root rot) celery, celeriac Rhizoctonia carotae (crater rot) carrot, celery, celeriac Thanatephorus cucumeris (crater rot) celery, celeriac Sclerotinia sclerotiorum (sclerotinia rot) carrot, parsnip, celery, celeriac, herbs Bacterial soft rots carrot, parsnip, celery, celeriac Pseudomonas sp. (bacterial blight) coriander Carrot motley dwarf virus complex carrot, parsley, dill Carrot mosaic potyvirus carrot, dill Parsnip mosaic potyvirus parsnip Parsnip yellow fleck sequivirus parsnip Celery mosaic potyvirus celery, celeriac, parsley, coriander, dill Psila rosae (carrot fly) all umbelliferous crops Noctuids (cutworms) all umbelliferous crops Cavariella pastinacae (willow-parsnip aphid) parsnip, carrot, celery, celeriac Cavariella aegopodii (willow-carrot aphid) carrot, parsnip, celery, celeriac, herbs Semiaphis dauci (carrot aphid) carrot Pemphigus pasekki (root aphid) caraway Myzus persicae parsnip, celery, celeriac Trioza apicalis (carrot psyllid) carrot, parsnip Euleia heraclei (celery leaf miner) celery, celeriac, parsnip, parsley Depressaria daucella (caraway moth) caraway Nematodes all umbelliferous crops Weeds all umbelliferous crops Basic strategy No resistant cultivars are available, but new Nantes/Berlicum hybrids show some tolerance. Fresh land cannot be guaranteed disease-free, but good field records of previous problems with cavity spot and soil tests based on ELISA can identify risk. Rotation should be as wide as possible. Double cropping should be avoided. Metalaxyl is an effective fungicide, but presents a risk of resistance and enhanced soil microbial degradation. Lower rates per hectare can be used by band spraying, only on mineral soils, provided the band covers the full row width. Main fungicides Sprays : metalaxyl. Seed treatment : metalaxyl, thiram. Helicobasidium purpureum (violet root rot) General The host range of Helicobasidium purpureum (syn. H. brebissonii) is very wide. Severe infection causes yellowing of foliage and wilting, usually in patches with late-season rotting and disappearance of foliage. Symptoms in the crop are: violet or purple dots (infection cushions) on roots with wefts of purple mycelium between infection cushions; a dense mycelial mat becoming cinnamon-brown with age; and purple mycelium visible at crown of carrot and on soil surface. Resting bodies (sclerotia) form around lateral roots. Soil sticks to infected roots. Root infection is not usually deep-seated but secondary organisms cause extensive damage. The main period of occurrence is September/November. The pathogen is widespread in all carrot and sugarbeet-growing areas. Sclerotia in soil germinate to give mycelium, which infects the root. Initial colonization is very slow and takes 3 months, but mycelium subsequently spreads over the root and from root to root. Mycelium also survives in infected carrot debris and can infect new host plants. Infected fragments can be spread by wind and machinery. Seasonal variation in severity is apparent. Typically, the disease occurs in patches and is aggravated by short rotations of root crops. Basic strategy No fungicides are available. Some cultivars appear to be less infected than others in the field but all can become infected to a high level. Crop rotation is the main means of control, and in this context cereal break crops are valuable. Rotation between susceptible crops (e.g. potatoes, sugarbeet) should be at least 5 years. Infested land should be avoided completely. Weeds should be well controlled and volunteer plants of susceptible crops removed. Infected carrots or soil from packing houses should not be dumped on land intended for root crop production. Early lifting avoids heavy infection. Erysiphe heraclei (powdery mildew) General Symptoms are diffuse white mycelium on leaves and petioles, becoming denser with age and leading to loss of foliage. Powdery mildew occurs commonly but especially in years with hot dry summers. It probably survives from season to season via a "green bridge" of volunteer plants or overlapping crops. Conidia are wind-blown and cleistothecia are also produced. Attacks follow hot dry conditions and fungal development can be very rapid in late summer/early autumn. Basic strategy Control can be influenced by hygiene practices, weed control and correct irrigation to minimize crop stress. The crop should be monitored before applying fungicide to estimate whether the roots have reached their final size, since there is no yield response if crop is of adequate root size. Fungicide sprays should be applied during the early stages of disease. Main fungicides Sprays: difenoconazole, dinocap, fenpropimorph, hexaconazole, iprodione, myclobutanil, sulphur, tetraconazole, thiophanate-methyl, triadimenol, triforine. Plasmopara nivea (downy mildew) General Yellowish spots develop on the upper surfaces of leaves and later turn black, while in damp conditions white patches of sporulating mildew appear on the underside of the leaves which eventually shrivel and drop. Basic strategy Diseased plant material should be destroyed after harvest. High plant density encourages high humidity and disease development, and the disease is more serious in irrigated crops. Umbelliferous host weeds should be controlled, and fungicides may be applied by spraying. Main fungicides Sprays: chlorothalonil, cymoxanil, mancozeb, maneb, metalaxyl. Alternaria dauci (alternaria blight) General Alternaria dauci can cause seedling death, and dark brown lesions on leaves leading to chlorotic margin with shrivelling and death of leaves. There are records of root invasion in field and in store. This disease is seed-borne and can survive in carrot debris for short periods if dry. There is also limited survival in soil. A high temperature of 22-24C plus 24-h leaf wetness will give severe infection. The optimum humidity for spore production is 96%. The life cycle can be completed in 8-10 days. The disease may also develop in store at temperatures >12C. In warmer countries, this may be the most serious disease of carrots. Another widespread carrot leaf pathogen Cercospora carotae causes symptoms similar to those of A. dauci. In contrast to A. dauci, it infects younger foliage rather than older leaves and appears earlier in the season. It is less damaging and not seed-borne. Basic strategy There is some evidence of varietal resistance to A. dauci but the current benefit from this is limited. Seeds should be tested, and fungicide-treated if the fungus is present. Hot-water treatment of the seeds at 54°C for 20 min is also effective. Debris from infected crops should be ploughed in as soon as possible after harvest to prevent spread to later crops. Crops should be monitored, and disease-development models used if possible, to determine whether application of fungicide sprays is necessary. Iprodione-resistant strains of A. dauci have been identified. Fungicides used against A. dauci will also control C. carotae. Main fungicides Sprays : chlorothalonil, difenoconazole, hexaconazole, iprodione, mancozeb, thiophanate-methyl. Seed treatment : iprodione. Alternaria radicina (black rot) General The host range of Alternaria radicina includes parsnips, celery and parsley, as well as carrots. Symptoms are seedling death, blackening of petiole base, leaf death, black rot of crown and rot of stored roots. High humidity is required for crown rot. The disease is seed-borne, but soil-borne transmission is most important. Infection can develop even at 0°C on stored roots. Basic strategy There is no evidence of varietal resistance. Seeds should be tested, and fungicide-treated if the fungus is present. Debris from infected crops should be ploughed in as soon as possible after harvest to prevent spread to later crops. Rotation should be a minimum of 3 years between crops. Fungicide sprays are recommended if there has been a previous history of the disease in the field. Main fungicides Sprays : chlorothalonil, difenoconazole, hexaconazole, iprodione, mancozeb. Seed treatment : iprodione. Sclerotinia sclerotiorum (sclerotinia rot) General Sclerotinia sclerotorium is polyphagous, attacking a very wide range of crops (carrots, potatoes, peas, rape) and weeds. Symptoms are browning of petioles followed by tissue collapse and death. White cotton-woolly mycelium containing black sclerotia is often seen on dead leaves in autumn. On the crowns, brown or black water-soaked lesions appear, with sclerotia attached to the surface. This is rare in field-stored crops but common in crops stored under refrigeration. The disease occurs in warm moist seasons, usually when foliage is dense and senescing. The fungus is widespread in European soils. Sclerotinia rot is mainly a problem in stored roots but may appear in the final packaged product if left at ambient temperatures. Soil-borne sclerotia germinate to give apothecia (producing ascospores) or can attack roots directly via mycelium. Air-borne ascospores discharged from apothecia are most likely to infect yellow or dead foliage. Once infection is established, the fungus spreads by direct contact of infected roots in field or cold storage. Basic strategy There is no evidence of varietal resistance. Crops should not be too densely planted. Application of nitrogenous fertilizer should be limited on more vigorous cultivars. Irrigation may help to reduce early foliage death. Site selection should be based on previous cropping with a wide rotation but this can be difficult to impose given the range of susceptible arable crops. Biological control is possible with the "biological fungicide" Coniothyrium minitans. It prevents pathogenic strains of S. sclerotiorum from penetrating and thereby infecting treated plants. Main fungicides Sprays : Coniothyrium minitans, dicloran, iprodione, vinclozolin. Mycocentrospora acerina (liquorice rot) General In addition to carrot, this fungus attacks parsnip, celery and a very wide range of weeds. The symptoms are brownish water-soaked lesions turning black on shoulder or tips of roots. Foliar symptoms are uncommon but include irregular brown or black leaf spots (rather like alternaria blight) and blackening of petioles. It is mainly a storage disease but the fungus can colonize cavity-spot lesions in the field. Infection of foliage occurs in the field, but symptoms on roots are generally not seen until after storage. Soil-borne chlamydospores ensure survival in soil for several years. Foliar and soil-borne phases establish inoculum which threatens the stored crop. Wet weather favours build-up on foliage. Development on stored roots takes place over several months at low temperatures. Basic strategy Where prevalent, Mycocentrospota acerina limits the storage potential of carrots. There is no evidence of varietal resistance. Minimizing the amount of damage during harvest reduces the incidence of the disease. Raised temperatures and high humidity to allow wound healing before storage has given useful control, but this favours attack by Sclerotinia sclerotiorum (q.v.). Older roots are more susceptible. A minimum rotation of 4 years between root crops is essential. Good control of the disease can be achieved by a pre-harvest sprays (if the field has a history of the disease). Main fungicides Sprays : benomyl, chlorothalonil, iprodione. Seed treatment : iprodione. Rhizoctonia carotae (crater rot) General In addition to carrot, this fungus attacks celery, swedes, cabbage and beet. The symptoms are sparse white mycelium over the root surface, with small depressions which enlarge into shallow craters, eventually becoming more deep-seated. Small white then brown sclerotia are produced on the surface of rotted roots. Infection occurs in the field but symptoms are not seen until storage. The fungus persists in wood of storage bins from which new infections are initiated. It may also be present in the soil (as sclerotia) and initiate infection before harvest. Development is favoured by humid refrigeration conditions and continues at low temperatures. Basic strategy There is no evidence of varietal resistance. On farms with a previous history of the disease, control with fungicide is advisable. Fungicides should be sprayed in the field once or twice before lifting, with sufficient pressure to ensure the fungicide reaches the crown. Damage during harvesting s