symptoms,pathogen and manaagement

1. STUDENT COURSE TEACHER
KEERTHANA. R Dr. S. PARTHASARATHY
ID. No. 2016021018 Assistant Professor (Plant Pathology).
COLLEGE OF AGRICULTURAL TECHNOLOGY
Affiliated to Tamil Nadu Agricultural University, Coimbatore
Kullapuram, Via Vaigai dam, Theni-625 562
MOTTLE STREAK VIRUS OF RAGI

2. RAGI – Eleusine corocana

3. SIGNIFICANCE
• Major cultivating area is Africa and Southern
Asia.
• It is rich in Calcium, Iron, Protein, and some rare
nutrients such as Methionine.

4. DISTRIBUTION
• The cultivation of finger millet widely distributed
extending from TamilNadu in South and Uttranchal in
North; Gujarat in West to Orissa in East and even
extending to north – eastern regions including
Sikkim.

5. SYMPTOMS
• Initial symptoms of mottle streak disease appear around
45 days after sowing in funnel leaves as small sparse
chlorotic specks.
• The virus affected plants are stunted and pale green in
colour.
• Later the specks coalesce leading to short streaks.
• Yellowing of leaves in severe infection.

6. • Infected plants produce more of nodal branches and
unproductive tillers.
• Failure of earhead emergence with sparse grains is
noticed during initial and later infection.
• Vector for this disease is Leafhopper –
Cicadulina bipuntella

7. Chlorotic streaks

8. Small specks on leaf

9. Severe infestation of mottle streak

10. Yellowing of entire plant

11. Mottling of centre plant

12. Symptom on earhead

13. Kingdom Virus
Phylum Negarnaviricota
class Monjiviricetes
order Mononegavirales
Family Rhabdoviridae
Genus Nucleo
Species rhabdovirus
SYSTEMIC POSITION

14. PATHOGEN - CHARACTERS
• This disease is caused by Nucleo rhabdovirus or
Potato Yellow Dwarf Virus is bacilliform, with one
type of particle of about 380 75nm.
• It is enveloped by with a clear model length of 178-
224nm, 59-76nm wide.
• Anal canal obvious and 8nm in diameter.

15. Pathogen

16. Microscopic view

17. TRANSMISSION
• The leaf hopper Cicadulina bipunctella was found
to transmit the virus efficiently up to 80%.
• The virus vector relationship revealed that 72 h of
acquisition access period, 5 days of inoculation
access period and nearly 30 days of incubation in
the host were required for attaining efficient
transmission.

18. Leaf hopper

19. FAVOURABLE CONDITION
• The grain is very highly resistant to storage
insect pest, even without any special care or
attention.
• It is reputed to remain in good condition even
when stored as long as fifty years.

20. MANAGEMENT
• Rogue out the affected plants.
• Spray systemic insecticides Methyl demeton
500ml/ha when notching symptom and repeat twice
if necessary at 20 days to control the vector.

21. REFERENCES
• Rose. J, Whitt. M (2001). “Rhabdoviridae: The
viruses and their replication”. pp – 1221-1244.
• http://www.sciencedirect.com