Xanthomonas campestris pv. phlei. [Descriptions of Fungi and Bacteria].

1987 ◽  
Author(s):  
J. F. Bradbury
Keyword(s):  
Geographical Distribution ◽  
Xanthomonas Campestris ◽  
Lolium Multiflorum ◽  
Seed Transmission ◽  
Vascular Bundles ◽  
Festuca Pratensis ◽  
Forage Grasses ◽  
Symptom Development ◽  
Young Leaves ◽  
Arrhenatherum Elatius

Abstract A description is provided for Xanthomonas campestris pv. phlei. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Phleumpratense. In inoculation tests Egli & Schmidt (1982) found that Phleum alpinum, P. arenarium, P. bertolonii (2 cvs.), P. phleoides and P. pratense (2 cvs.) were all highly susceptible. Lolium multiflorum showed mild symptoms in this test, but none in another. Other grasses, including Festuca pratensis, Arrhenatherum elatius and Poa trivalis showed little or, more often, no symptom development. DISEASE: Bacterial wilt of timothy grass. The symptoms are the same as those caused by X. campestris pv. graminis on other forage grasses. Young leaves curl and wither and shoots remain stunted or die. In some plants growth continues poorly and small, distorted inflorescences are produced. Chlorotic and necrotic zones form along the vascular bundles of older leaves, often extending to the sheaths. Bacterial streaming is often visible under the microscope from the cut edges of infected tissue. GEOGRAPHICAL DISTRIBUTION: Norway (Egli & Schmidt, 1982) and Belgium (61, 6162) are the only reports so far, but the disease is probably more widespread in Europe than this would suggest. TRANSMISSION: As for X. campestris pv. graminis transmission within the crop is thought to be mainly by mowing machinery. The possibility of seed transmission should not be overlooked, although this has not been proved.

Xanthomonas campestris pv. arrhenatheri. [Descriptions of Fungi and Bacteria].

1987 ◽  
Author(s):  
J. F. Bradbury
Keyword(s):  
Geographical Distribution ◽  
Xanthomonas Campestris ◽  
Lolium Multiflorum ◽  
Phleum Pratense ◽  
Vascular Bundles ◽  
Forage Grasses ◽  
Poor Growth ◽  
Poa Trivialis ◽  
Young Leaves ◽  
Arrhenatherum Elatius

Abstract A description is provided for Xanthomonas campestris pv. arrhenatheri. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Arrhenatherum elatius. By inoculation strain 705 gave much less severe symptoms on Alopecuruspratensis and Dactylis glomerata, but other grasses tested were not diseased (Egli et al., 1975) Three other strains (711, 719, and 725) gave mild symptoms on Lolium multiflorum, and one (730) gave a slight reaction on Phleum pratense. The reactions on Festuca pratensis and Poa trivialis were negative or negligible (Egli & Schmidt 1982). It is unlikely that the above inoculated hosts would be infected naturally. DISEASE: Bacterial wilt of tall oat grass. The symptoms are identical to those caused by X. campestris pv. graminis on other forage grasses. They are first seen at the heading stage when young leaves curl and wither and shoots remain stunted or may die. In some plants poor growth continues and small distorted inflorescences are produced. Chlorotic and necrotic zones form on older leaves along the vascular bundles, often extending into the sheaths. Bacterial streaming may be seen under the microscope from cut ends of vascular bundles of infected tissue mounted in water. GEOGRAPHICAL DISTRIBUTION: Switzerland. All of Egli's isolates came from that country and the pathogen has not yet been reported from elsewhere. TRANSMISSION: As with X. campestris pv. graminis transmission within the crop is thought to be mainly by mowing machinery.

Xanthomonas campestris pv. poae. [Descriptions of Fungi and Bacteria].

1987 ◽  
Author(s):  
J. F. Bradbury
Keyword(s):  
Geographical Distribution ◽  
Bacterial Wilt ◽  
Xanthomonas Campestris ◽  
European Countries ◽  
Vascular Bundles ◽  
Forage Grasses ◽  
Poa Trivialis ◽  
Young Leaves ◽  
Means Of Transmission ◽  
Heading Stage

Abstract A description is provided for Xanthomonas campestris pv. poae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Naturally infects Poa trivialis. By artificial inoculation Poafertilis and P. nemoralis are both moderately susceptible, P. annua rather less susceptible, and P. pratensis and P. compressa little or not at all affected. DISEASE: Bacterial wilt of rough stalked meadow grass (Poa trivialis). The symptoms are the same as those produced by X. campestris pv. graminis on other forage grasses. At the heading stage young leaves are seen to curl and wither, and shoots remain stunted or die. Some plants produce small, distorted inflorescences. Chlorotic and necrotic areas form along the vascular bundles of older leaves and often extend into their sheaths. Bacterial streaming is usually visible under the microscope. GEOGRAPHICAL DISTRIBUTION: Switzerland. Probably present but unrecognised in some other european countries. TRANSMISSION: Within the crop the main means of transmission is probably mowing machinery.

Xanthomonas campestris pv. graminis. [Descriptions of Fungi and Bacteria].

1987 ◽  
Author(s):  
K. E. Reay
Keyword(s):  
Geographical Distribution ◽  
Festuca Arundinacea ◽  
Xanthomonas Campestris ◽  
Natural Infection ◽  
Dactylis Glomerata ◽  
Phleum Pratense ◽  
Vascular Bundles ◽  
Poor Growth ◽  
Young Leaves ◽  
Natural Host Range

Abstract A description is provided for Xanthomonas campestris pv. graminis. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Lolium italicum, L. multiflorum, L. perenne, Dactylis glomerata, Festuca pratensis, and Trisetum flavescens. Single cases of natural infection of Agropyron repens, Phalaris arundinacea and Phleum pratense are also recorded (62, 241), but their status in the natural host range is unknown. In inoculation tests (Egli et al., 1975; Egli & Schmidt, 1982) the following were highly susceptible: Alopecurus pratensis, Dactylis glomerata, Festuca arundinacea, F. pratensis, F. rubra, Lolium loliaceum, L. multiforum, L. parabolicae, L. perenne, L. remotum, L. temulentum, Phleum arenarium and P. bertolonii. Showing much less susceptibility were Agrostis alba, Arrhenatherum elatius, Phleum alpinum, P. phleoides, P. pratense, Poa annua, P. compressa, P. fertilis, P. memoralis, P. pratensis and P. trivialis. Leyns et al. (61, 6162) found that Agrosas tenuis and Festuca ovina were moderately susceptible when inoculated. Egli et al. (1975) recorded doubtful symptoms on Hordeum vulgare and Triacum aestivam on inoculation, but consider that they are unlikely to be naturally infected. DISEASE: Bacterial wilt of forage grasses. Symptoms usually first noticed at the heading stage, when young leaves curl and wither, and shoots remain stunted or may die. Other plants will continue to make poor growth and produce small, distorted inflorescences. Chlorotic and necrotic zones form on the older leaves along long stretches of vascular bundles, often extending into the sheaths. Bacterial streaming may be seen under the microscope from the cut ends of vascular bundles of infected tissue mounted in water. GEOGRAPHICAL DISTRIBUTION: CMI Map 533, ed. 1, 1979 lists France, Germany, Switzerland and Wales, to which must be added Scotland (63, 2925), Belgium (61, 4199), Netherlands, Norway (62, 241), and New Zealand (62, 241). Possibly in USA (IL; 61, 5045) though this disease is currently attributed to a Rickettsia- like organism. TRANSMISSION: Within the crop transmission is presumed to be by the blades of mowing machines.

Septoria helianthi. [Descriptions of Fungi and Bacteria].

1970 ◽  
Author(s):  
P. Holliday
Keyword(s):  
Helianthus Annuus ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
Seed Treatment ◽  
Seed Transmission ◽  
Adaxial Surface ◽  
Young Leaves

Abstract A description is provided for Septoria helianthi. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Helianthus annuus, Helianthus grosseserratus and Helianthus rigidus. DISEASE: Leaf spot of sunflower. Yellowish spots up to 1.5 cm develop over the whole lamina, gradually turning necrotic and becoming almost black. The numerous pycnidia are mostly on the adaxial surface. The lesions have a polygonal outline, being sharply delimited by the veins. Infection may begin on the cotyledons and young leaves, spreading to later developing leaves. Severe attacks lead to defoliation and loss in yield. GEOGRAPHICAL DISTRIBUTION: Fairly widespread in E. Europe and the U.S.S.R. in Asia, China, Japan, Australia (Qd.); E. and S. Africa, N. America (CMI Map 468, ed. 1, 1970). TRANSMISSION: Overwintering occurs in host debris. Seed treatment is recommended although seed transmission does not appear to have been demonstrated. Introduction of the fungus into Hungary may have been via seed (43, 2013).

Xanthomonas axonopodis. [Descriptions of Fungi and Bacteria].

1977 ◽  
Author(s):  
J. F. Bradbury
Keyword(s):  
Geographical Distribution ◽  
Seed Transmission ◽  
Saccharum Officinarum ◽  
Vascular Bundles ◽  
Xanthomonas Axonopodis ◽  
Digitaria Decumbens ◽  
Pasture Grasses ◽  
Tropical America ◽  
Rain Splash ◽  
Short Time

Abstract A description is provided for Xanthomonas axonopodis. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Axonopus scoparius, A. micay, A. compressus and A. affinis. Also able to infect by inoculation Digitaria decumbens, Hypharrhenia rufa, Panicum sp. (Guinea grass) and Saccharum officinarum (54, 5464). DISEASE: Gummosis of Imperial and Micay grasses, important pasture grasses in tropical America. Diseased stems usually stand out from healthy ones in the same tuft by their elongated, partly bare appearance with a few pale, yellowish leaves at their ends, giving a characteristic flag-like appearance. Closer examination shows many diseased leaves with pale stripes running parallel to the main veins. After cutting diseased Imperial grass the new shoots are feeble and twisted, and often wither in a short time. Subsequent shoots behave in the same way. In severe attacks of whole tuft may shrivel and die. Such tufts are very easily pulled from the soil. When diseased stems are cut across, especially in the rainy season, minute droplets of yellowish bacterial ooze appear in a short time. In longitudinal cuts the vascular bundles are seen to be stained reddish or brownish, especially near the nodes. Masses of bacteria and mucilage are found in vessels when examined under the microscope. GEOGRAPHICAL DISTRIBUTION: Colombia. TRANSMISSION: Mainly by machete and other agricultural implements. Cattle can infect young shoots when grazing, evidently transmitting the bacteria in their saliva. Trampling by cattle and man and the passage of wheeled vehicles can also transmit the disease, and rain splash can carry infection from the exudate of recently cut stems. Insect transmission is not thought to be important and the bacteria do not survive free in the soil (46, 666). Seed transmission is also thought to occur (43, 2799c).

Xanthomonas campestris pv. sesami. [Descriptions of Fungi and Bacteria].

1981 ◽  
Author(s):  
J. F. Bradbury
Keyword(s):  
Geographical Distribution ◽  
Leaf Spot ◽  
Bacterial Blight ◽  
Xanthomonas Campestris ◽  
Seed Transmission ◽  
Sesamum Indicum ◽  
Leaf Spot Disease ◽  
Spot Disease ◽  
Water Splash ◽  
Olive Green

Abstract A description is provided for Xanthomonas campestris pv. sesami. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Sesamum indicum (Pedaliaceae). DISEASE: Bacterial blight of sesame or simsim; known as 'Marad ed Dum' in the Sudan. Mainly a leaf spot disease, this starts as tiny dark olive green spots, which increase in size, becoming dark red-brown to black, and about 2-3 mm. They may be rounded or angular, and may coalesce to involve larger areas of leaf. Stems and capsules may also be infected, having oval, slightly raised, dark red-brown lesions. GEOGRAPHICAL DISTRIBUTION: Sudan and India (CMI Map 494, ed 2, 1973) to which must be added Venezuela, now confirmed (54, 524; 56, 2615). TRANSMISSION: Within a crop by water splash, wind-driven rain etc. ; from one area to another by seed transmission (47, 593). Survival in seed is up to 16 months (51, 400), in soil up to 6 months.

Asperisporium caricae. [Descriptions of Fungi and Bacteria].

1972 ◽  
Author(s):  
M. B. Ellis
Keyword(s):  
Geographical Distribution ◽  
Experimental Work ◽  
West Indies ◽  
Carica Papaya ◽  
Black Spot ◽  
Seed Transmission ◽  
Leaf Fall ◽  
Mature Leaves ◽  
Early Suggestion ◽  
Young Leaves

Abstract A description is provided for Asperisporium caricae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Carica papaya. DISEASE: Black spot, blight or 'rust' of papaw (Carica papaya). Water-soaked spots on mature leaves become necrotic, usually circular and up to 4 mm diam., the dark conidia! masses being conspicuous on the under surface. Abundant spotting causes defoliation and over 50% leaf fall can occur. Similar spots form on the fruit; they cause shallow lesions and no decay. Young leaves are not attacked. GEOGRAPHICAL DISTRIBUTION: Restricted to Central and S. America, West Indies and USA (Florida, Texas) (CMI Map 488, ed. 1, 1972). TRANSMISSION: Presumably air dispersed but no experimental work has been reported and there is no confirmation of an early suggestion of seed transmission (4: 682).

Pyrenophora dictyoides. [Descriptions of Fungi and Bacteria].

1976 ◽  
Author(s):  
M. B. Ellis
Keyword(s):  
New Zealand ◽  
North America ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
Leaf Blade ◽  
Seed Transmission ◽  
Festuca Pratensis ◽  
Net Blotch ◽  
Meadow Fescue ◽  
Brown Leaf

Abstract A description is provided for Pyrenophora dictyoides. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Festuca, Lolium, Phleum, Poa. DISEASE: Causes net blotch and leaf spot primarily of fescues. Irregular brown leaf lesions with a delicate netted pattern are formed which may result in the withering of the whole leaf blade. Common on meadow fescue (Festuca pratensis) causing net-blotch lesions and occasionally found on Lolium and other grasses. GEOGRAPHICAL DISTRIBUTION: North America, Europe, Australia and New Zealand. TRANSMISSION: By spores, overwintering on leaf bases, crop debris, etc., and by seed transmission (50, 3873).

Long-term fertilization experiments on a natural grassland on calcareous meadow soil

2010 ◽  
Vol 59 (2) ◽  
pp. 255-268
Author(s):  
István Harmati
Keyword(s):  
Trifolium Pratense ◽  
Poa Pratensis ◽  
Festuca Pratensis ◽  
Meadow Soil ◽  
Medicago Lupulina ◽  
Arrhenatherum Elatius ◽  
Natural Grassland ◽  
Fertilization Experiments ◽  
Agropyron Repens

Sekély humuszos szintű, erősen karbonátos réti talajon kialakult természetes (Achilleo-Festucetum pseudovinae) gyepen beállított tartamkísérletekben vizsgáltuk a műtrágyázás kérdéseit a gyep növényi összetételének megjavítása, termésének növelése és minősége javítása céljából. A kísérlet humuszban gazdag, nitrogénnel és káliummal igen jól ellátott, de foszforban szegény talaján az N- és P-műtrágya 2-2 adagját szólóban és kombinációikban alkalmaztuk. Az öntözetlen kísérletet 28, az öntözöttet 14 éven át folyamatosan, széleskörűen vizsgáltuk. Megállapításainkat a következőkben foglaljuk össze. – A gyep növényi összetételét a N- és a P-műtrágyák adagjaiktól és kombinációiktól függően megváltoztatták. A nitrogén a füvek, a foszfor a pillangósok versenyképességét fokozta és segítette elő növekedését. Az önmagában alkalmazott N-műtrágya a talaj nagyfokú P-szegénysége miatt nem gyakorolt pozitív hatást a gyepre. A P-műtrágya viszont kedvező változásokat okozott: a füvek fejlődésének elősegítése mellett nagymértékben növelte a pillangósok borítási értékét és tömegarányát, különösen az öntözött parcellákon. Öntözetlen viszonyok között a réti perje (Poa pratensis), a sovány csenkesz (Festuca pseudovina) és a komlós lucerna (Medicago lupulina) alkotta a gyep termésének túlnyomó részét, néhány egyéb fű- és pillangósvirágú komponens társaságában. Az öntözött kísérletben a pillangósok abszolút uralma mellett gyakran a réti perje jutott vezető szerephez. A pillangósok közül az eperhere (Trifolium fragiferum), a komlós lucerna (Medicago lupulina) és a vörös here (Trifolium pratense) váltakozva jutott uralomra. Az időjárás nagyban befolyásolta a gyep pillangós komponenseinek tömegarányát. Az NP kombinációkban a pillangósok tömegaránya erősen lecsökkent, különösen a nagyobb N-adag használata esetén. Öntözetlen területen a sovány csenkesz és a réti perje változó arányban alkotta a gyep termésének túlnyomó részét. Az öntözött parcellákon azonban a réti perje abszolút uralkodóvá vált és az egyre jobban előretörő tarackbúza (Agropyron repens) is jelentősen részt vett a termés kialakításában, elsősorban a nagyobb N-dózisú kombinációkban. A kísérlet 3. évtizedében a csapadékos években megjelent a francia perje (Arrhenatherum elatius) és a réti csenkesz (Festuca pratensis) is. – A gyep termését az önmagában alkalmazott N-műtrágya nem növelte jelentősen. Ezzel szemben a P-műtrágya nagy hatékonysággal 2–4-szeresére (3–5 t·ha–1-ra) növelte a gyep szénatermését, elsősorban a pillangósok nagyarányú térhódítása révén. 1 kg P2O5 öntözetlen körülmények között 43, míg öntözöttben 68 kg szénaterméstöbbletet eredményezett, sokévi átlagban. A 90 kg P2O5·ha–1 adag néhány év után soknak bizonyult. A legjobb eredményt a 200 kg N·ha–1 + 60 kg P2O5·ha–1 adaggal értük el, amellyel az öntözetlen területen – 28 év átlagában – 7,87, öntözötten – 14 év átlagában – 7,12 t·ha–1 szénatermést kaptunk. Az időjárás nagymértékben befolyásolta a termés mennyiségét és minőségét, legfőképpen a pillangósok tömegarányának változása révén, különösen az öntözetlen kísérletben. A három növedék tömegének aránya 7 évi átlagban, az öntözetlen kísérletben a szóló foszforkezeléseknél 48:37:15%, míg az NP kombinációknál 56:35:9% volt. Az öntözött területen ezek az arányok az előbbi sorrendben: 39:49:12, illetve 43:41:16%. A nitrogénből számított nyersfehérjehozam sokévi átlagban az öntözetlen kísérletben 428–550, míg az öntözöttben 560–760 kg·ha–1 volt. – A talaj felvehető tápanyagtartalma az évek során jelentősen megváltozott, különösen a talaj 0–10 cm-es rétegében. A P-trágyázás önmagában, de az NP kombinációiban is az adagoktól, illetve az ezek hatására kialakult termések mennyiségétől függő mértékben növelte a talaj P-tartalmát. A legjobbnak a 200 kg N·ha–1 + 60 kg P2O5·ha–1 kezelésű parcellákban bizonyult: a kísérlet 22. évében a talaj 0–10 cm-es rétegében a P-tartalom 260 mg P2O5·kg–1 lett, ami az erősen karbonátos talajok esetében igen jó P-ellátottságnak mondható. A K-ellátottság azonban az NP-kezeléseknél az optimális szint alá csökkent (172 mg K2O·kg–1) a termések nagyarányú K-kivonása következtében. Ezért néhány évi NP-trágyázás után K-pótlásra is szükség van.

Ascochyta desmazieresii. [Descriptions of Fungi and Bacteria].

1980 ◽  
Author(s):  
E. Punithalingam
Keyword(s):  
Geographical Distribution ◽  
Leaf Spot ◽  
Crop Residues ◽  
Lolium Multiflorum ◽  
Leaf Tissue ◽  
Lower Side ◽  
Soil P ◽  
Wet Weather ◽  
Irish Republic

Abstract A description is provided for Ascochyta desmazieresii. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Lolium multiflorum and L. perenne. DISEASE: Glume and leaf spot of Italian and perennial ryegrasses. At first leaf lesions start as small purplish or chocolate-brown spots with a distinct red-purple margin. With time these enlarge, become irregular or elliptical, up to 5 mm long and distinctly visible on both sides of the leaves. Finally the centres of older lesions fade to fawn to straw yellow with numerous pycnidia immersed within the leaf tissue on both sides of the leaves but usually abundant pycnidia occur on the lower side. GEOGRAPHICAL DISTRIBUTION: Asia (Japan); Europe (Belgium, Czechoslovakia, Denmark, France, Irish Republic, UK); N. America (USA, California, Oregon, Washington); S. America (Chile, Brazil). TRANSMISSION: No specific studies reported; infection is presumably spread by air-borne conidia in wet weather or heavy dews. The fungus is also probably carried over on crop residues and debris in soil.

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