This document discusses several species of beetles that vector plant viruses and diseases. It provides details on the Maize chlorotic mottle virus, which is transmitted by cereal leaf beetles, corn flea beetles, and corn rootworm beetles in a non-propagative manner. It also discusses beetle vectors of Broad bean mottle virus, Turnip crinkle virus, Cocksfoot mild mosaic virus, Turnip yellow mosaic virus, Potato virus X, and Cucumber chlorotic mottle virus. Finally, it summarizes bacterial and fungal diseases of plants that are spread by beetles, such as Stewart's wilt of corn, bacterial wilt of cucurbits, Dutch elm disease, and laurel w

1.  Chrysomelidae (leaf beetles),
 Scolytidae (bark beetles),
 Coccinellidae (lady bird beetles),
 Curculionidae (weevils or snout beetles) and
 Melonidae (blister beetles)
 Machlomovirus
 Bromovirus
 Carmovirus
 Sobemovirus
 Tymovirus
 Potexvirus
 Tobamovirus
Presented by
ARUNKUMAR. P

2. • Maize chlorotic mottle virus (Machlomovirus)
• Broad bean mottle virus (Bromovirus).
• Turnip crinkle disease (Carmovirus).
• Cocks foot mild mosaic disease (Sobemovirus).
• Turnip yellow mosaic disease (Tymovirus).
• Potato virus X disease (Potexvirus).
• Cucumber chlorotic mottle disease
(Tobamovirus).
VIRUS
• Stewarts wilt of corn.
• Bacterial wilt of cucurbitsBACTERIA
• Dutch elm disease.
• Laurel wilt disease.FUNGI

3.  Contains ssRNA with isometric particles (hexagonal)
 Two important strains- Peru (MCMV-P) (Jensen, 1985) and
Kansas, USA (MCMV-K)
Mosaic pattern
Yellow streaks running parallel to veins in the leaf.
These streaks coalesce to form a mottled leaf.
Plants bore malformed, have small cobs and
Male flowers of affected plants- reduced in size.
L. R. Nault et al.,1978

4. L. R. Nault et al.,1978
Two other insect species with mandibulate mouthparts,
- Paeonia japonica and Agrotis ipsilon failed to transmit
transmission of a plant virus.
Oulema melanopa- Aphid species transmits Maize chlorotic
mottle virus
Transmission of MCMV by six chrysomelid beetle species.
 Cereal leaf beetle
 Two corn flea beetle species
 Three corn rootworm species
Virus- present in the gut and hemolymph of vector species and
transmission is entirely mechanical.

5.  ssRNA
 Isometric
 Non-enveloped
 Contains (twenty-one to twenty-three%) nucleic acid and
seventy-seven% protein.
Mosaic/mottle on leaves of upper canopy/fresh growth
necrosis of lower canopy leaves.
Necrosis and shriveling of seeds

6.  Striped cucumber beetle- Acalymma trivttata,
 Spotted cucumber beetle- Diabrotica undecimpunctata
 Bean weevil- Sitona lineatus and
 Brape colaspus- Colaspis flavida
 Circulative non-propagative manner.
 In addition to beetles, Spodoptera exigua- vector of this virus
with a transmission efficiency of 31%.
Loren J. Giesler et al.,2002

7.  RNA as nucleic acid
 Isometric
 Leaf crinkling
 Yellow mottling/mild mottling on Brassica crops.
Transmission through flea beetles:
 Genus: Phyllotreta and Psylliodes
N.S.Butter.,2018

8.  Virus belonging to Sobemovirus genus
 ssRNA virus
 Isometric particles
 Attacks Family- Gramineae
 Light green streaks in the leaves.
 Infective Sap-transmissible
 Secondary spread- Aphids and Beetles(Dactylis glomerata)
E.P.Serjeant.,1966

9.  RNA with particles of isometric symmetry
 Attacks the Family- Cruciferae
 Virus is transmissible through sap and flea beetles
 Virus-vector relationship between vector beetle and virus is
entirely mechanical.
 Flea beetles Phyllotreta and Psylliodes can acquire the virus in
an acquisition access period of a few minutes.
Mustard beetle, Phaedon cochleariae- larvae are also able to
transmit the virus.
Larvae- acquire the virus within (1 to 3 mints)
Latent period- 24 hours.

10. Longitudinal section through the alimentary canal of an adult flea-beetle, Phyllotreta sp.,
showing the valve which, being between the crop and the mid-gut, does not prevent
regurgitation of food materials from the crop
Roy Markham and Kenneth Smith.,1949

11.  Synonym of Potato mild mosaic virus (PMMV).
 Mottling
 Necrotic spotting, are conspicuous in diseased potato
plants.
 ssRNA, filamentous
 Family: Alphaflexiviridae
 Monopartite genome virus
 Host range includes Solanaceae and sixteen other families
of crop plants.

12.  Fungi (Synchytrium endobioticum),
 Grasshoppers (Melanopus differentials; Tettigonia
viridissima)
 Beetles (Epilachna ocellata)
Nagaich et al., 1972

13.  RNA virus
 belongs to Genus Tobamovirus
 Spread of this virus is via contaminated tools, insects with
chewing mouthparts (beetles), seed, pollen and dodder.
 It is known to infect cucumber, melon, water melon, bottle
gourd and vegetable marrow.
 The leaf beetle Aulacophora femoralis is an efficient vector of
this virus.
N.S.Butter.,2018

14.  Leaf mottling
 Blistering and
 Leaf deformations.
 Fruits and fruit peduncles show necrotic patches/spots.
 In addition, yellow patches are also seen in the fruit flesh upon
dissection.
 Flesh is mushy, broken and contain cavities.

15. • Caused by Erwinia stewartii in corn in USA and Canada.
• Damage- seedling stage.
• Corn flea beetles- cause wounds, serve as the substratum for the
spread of disease.
• The leaf tissues around feeding areas become water soaked.
 Bacteria- present in the alimentary canal of flea beetles
 Spread- through regurgitation and fecal matter
 Corn flea beetles- serve as delivery vessels for the inhabitant
bacteria.

16. • Pale yellow linear streaks
running parallel to veins
• Necrotic
near the soil level
• Main stem gets broken
• Apical growth of the plant- arrested

17. Photo source: Jerald K. Pataky.,2004

19. Source of photo: Jason Andrew Smith et al.,2013

20.  Fungi, Ophistoma ulmi and O. novo-ulmi, and is
transmitted by beetles
 In America, it is transmitted by Hylurgopinus
rufipes (Eichh.) and Scolytus multistriatus.
 In Europe, its spread is through S. Scolytus, S.
multistriatus, S. pygmaeus, S. kirschii species
of bark beetles.
• Flagging
• Wilting of leaves
• Plant dies within 1–3 years

21. Photo source: Linda Haugen.,2014

22. X. glabratus
 Disease caused by one of the symbionts (Raffaelea
lauricola) of Red bay ambrosia beetle, Xyleborus glabratus
(Coleoptera)