Rhizomania, also known as root madness or crazy root, is a disease of sugar beet caused by the Beet necrotic yellow vein virus transmitted by the soil-borne fungus Polymyxa betae. It was first discovered in 1950 in Japan and has since spread to many sugar beet growing regions worldwide. The disease causes significant losses in root and sugar yield, with infection in Serbia estimated to have caused losses on over 5,177 hectares. Key symptoms include gridling and darkening of the root system, stunted fleshy roots, and chlorosis in leaf veins. Management strategies focus on cultural practices like early planting, resistant varieties, and soil fumigation to control the vector.

1. RHIZOMANIA IN SUGAR BEET
STUDENT
Miss.KOWSALYA.S
ID. No: 2015021064
COURSE TEACHER
Dr. PARTHASARATHY S
Asst. Professor (Plant Pathology)

2. HISTORY
• Rhizomania also called as “root madness” or “crazy
root”
• First discovered in 1950 at Japan
• 1959- discovered in Italy
• Currently virus was found in six Asian countries, 22
European countries and parts of USA

3. DISTRIBUTION
• Japan, Europe, United states, California,
Colarado and in the Red river valley of
Minnesota

4. LOSSES
• Rhizomania causes significant losses in root
and sugar yield
• In Serbia (Yugoslavia) it causes loss
approximately of 5177 ha of field

5. HOSTS
• Beet root, sugar beet, chicory, tobacco and
spinach

6. SYMPTOMS
ROOTS:
• Gridling of lower part of the root
• Dense and dark root hairs leads to the drying
of roots from white to brown and new rootlets
produced continuously this is called “salt and
pepper beard”
• In severe cases taproot restricted two or three
inches below the soil surface results in a “wine
glass” shape

7. • Vascular system becomes darkened in
longitudinal sections
• Early season infection results in stunted fleshly
roots
• Leaf – chlorosis in leaf veins and necrotic
symptom
• On foliage- chlorosis with erect and upward
posture

8. ©alamy stock.in

9. ©extension publications unl.edu

10. SYSTEMIC POSITION
• GROUP – Group IV ((+)ssRNA)
• FAMILY – Benyviridae
• GENUS – Benyvirus
• SPECIES – Beet yellow vein virus

11. PATHOGEN
• Beet necrotic yellow vein virus
• Vector- soil borne fungi Polymyxa betae
• It is a obligate parasite
• Vector can survive more than 10 years in the
soil in the form of cystososri
• Virus rigid rod particles with divided genomes
(3-5 molecules of ssRNA)

12. ©cropwatch.unl.edu

13. ©researchgate.com

14. TRANSMISSION

15. MODE OF SPREAD
• Primary spread - rains splashes and soil
• Secondary spread – farm machinery

16. FAVOURABLE CONDITION
• Temperature – high (15-28°C)
• Humidity – optimum
• pH- neutral

17. INTEGRATED DISEASES MANAGEMENT
CULTURAL MANAGEMENT :
• Early planting of crops can reduce the
infection of plants
• Use of resistant cultivars can reduces infection
to some extend
• Vector can be controlled by soil fumigation