Apple mosaic ilarvirus

Presentation on theme: "Apple mosaic ilarvirus"— Presentation transcript:

1 Apple mosaic ilarvirus
Created by …….., a first year student of the second group of the faculty of plant protection, biotechnology and ecology

2 Taxonomy and relationships
Data collated by R.W. Fulton, 1985. Taxonomy and relationships Ilarvirus: Bromoviridae (subgroup 3)

3 mild apple mosaic virus, severe apple mosaic virus.
Nomenclature Synonyms birch line pattern virus, birch ringspot virus, Dutch plum line pattern virus, European plum line pattern virus, hop A virus, horse chestnut yellow mosaic virus, rose mosaic virus (Thomas, 1980; 1981; 1982; 1984a and b). Acronym ApMV Strains mild apple mosaic virus, severe apple mosaic virus. ICTV decimal code

4 Host range and symptoms Natural host range and symptoms
First reported in Rosa spp. and Malus domestica; from the U.S.A.; by White (1928) and Bradford and Joley (1933). Natural host range and symptoms Symptoms persist. Malus domestica and Malus spp. - mosaic. Rosaceae (many species) - necrotic ringspots. Humulus spp. - mottling.

5 Geographical distribution
Transmission Virus transmitted by mechanical inoculation; transmitted by grafting (of roots); possibly not transmitted by seed; but probably transmitted by pollen to the pollinated plant. Geographical distribution Probably distributed worldwide.

6 Experimental host range
Many (>9) families susceptible. Experimentally infected plants mostly show necrotic and chlorotic local lesions, systemic mottles, mosaics and ringspots.

7 Physical and biochemical properties Properties of particles in sap
TIP: 54 °C (in extracts stabilized with mercaptoethanol). LIV: days (2-4 hours in buffered extracts, 2-5 minutes in crude sap). DEP: log10minus 3 (in stabilized 2-mercapto-ethanol sap diluted in buffer). Leaf sap contains few virions. Electron microscopy: treat with 1% glutaraldehyde before negative staining.

8 Particle morphology Virions isometric; not enveloped; 25 and 29 nm in diameter (and probably a third size); rounded in profile (and pleomorphic); without a conspicuous capsomere arrangement.

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10 Biochemical properties
Physical properties Three sedimenting components in purified preparations; sedimentation coefficient of the fastest 117 S; of the other(s) 88 and 95 S. Biochemical properties Virions contain 16 % nucleic acid (all components); 84 % protein; 0 % lipid. Genome consists of RNA; single-stranded; of three parts. Genomic nucleic acid isolated by Gonsalves and Fulton (1977). Additional factor required for infectivity (coat protein).

11 Replication does not depend on a helper virus.
Features of the genome Non-genomic nucleic acid found in the virions; is subgenomic mRNA; for the coat protein. Sub-genomic mRNA found in infected cells. Features of proteins Virion protein(s) one; Mr  Method of preparation: Gonsalves and Fulton (1977). Replication Replication does not depend on a helper virus.

12 Taxonomy and relationships Ilarvirus: Bromoviridae (subgroup 3)
Virus(es) with serologically related virions Prunus necrotic ringspot virus, but distantly. Virus(es) with serologically unrelated virions Tobacco streak, Tulare apple mosaic, prune dwarf, citrus variegation, citrus leaf rugose, asparagus 2 and elm mottle viruses.

13 Diagnostically susceptible host species and symptoms
Amaranthus tricolor, Teramnus uncinatus - small brown local lesions. Catharanthus roseus, Vigna unguiculata - systemic chlorotic lines and rings. Chenopodium quinoa - mottling.

14 Crotalaria juncea - veinal necrosis.
Cucumis sativus - chlorotic local lesions, systemic chlorosis, stunting. Cyamopsis tetragonoloba - necrotic local lesions. Torenia fournieri - bright yellow mosaic.

15 Diagnostically insusceptible host species
Beta vulgaris, Datura stramonium, Helianthus annuus, Lactuca sativa, Nicotiana tabacum.

16 Maintenance and propagation hosts
Catharanthus roseus, Cucumis sativus, Phaseolus vulgaris (only certain isolates), Vigna unguiculata (only certain isolates). Assay hosts (Local lesions or Whole plants) Cyamopsis tetragonoloba (L), Cucumis sativus, (W).

17 Susceptible host species
Amaranthus retroflexus Amaranthus tricolor Cassia occidentalis Catharanthus roseus

18 Cucumis sativus Cucurbita maxima Cyamopsis tetragonoloba Fragaria vesca Gomphrena globosa

19 Nicotiana benthamiana
Malus domestica Melilotus albus Momordica balsamina Nicandra physalodes Nicotiana benthamiana

20 Rosa Rosaceae Teramnus uncinatus Torenia fournieri Tropaeolum majus

21 Insusceptible host species
Beta vulgaris Cucurbita pepo Cyamopsis tetragonoloba Datura stramonium Helianthus annuus

22 Families containing susceptible hosts
Amaranthaceae (3/3) Apocynaceae (1/1) Cannabidaceae (1/1) Chenopodiaceae (2/3) Convolvulaceae (1/1) Cucurbitaceae (4/5) Euphorbiaceae (1/1) Leguminosae-Caesalpinioideae (1/1) Leguminosae-Papilionoideae (7/8) Polemoniaceae (1 /1) Rosaceae (3/3) Scrophulariaceae (1/1)

23 Families containing insusceptible hosts Sources of host-range data
Chenopodiaceae (1/3) Compositae (2/2) Cucurbitaceae (1/5) Leguminosae-Papilionoideae (2/8) Solanaceae (3/10) Sources of host-range data Fulton (1952); Kristensen and Thomson (1963); Posnette and Ellenberger (1963).

24 Thank you for your attention