BBTV is the most serious virus disease of bananas and plantains. It occurs in Africa, Asia, Australia, and South Pacific islands. The virus is transmitted in a persistent, circulative, non-propagative manner by the banana aphid, Pentalonia nigronervosa, which has worldwide distribution. The virus is also spread through infected planting material. All banana cultivars are thought to be susceptible, with no known sources of resistance. The typical symptoms of bunchy top of banana are very distinctive and readily distinguished from those caused by other viruses of banana. Infected plants exhibit a rosetted or ‘bunchy top’ appearance. Once infected, plants do not recover.

1. Presented To:
Dr. Mihira Kumara Mishra
Professor
Dept. of Plant Pathology
College Of Agriculture, OUAT, BBSR
Presented By:
Om Prakash Barik
Adm. No. – 201222217
1st Yr. MSc. Ag. (Plant Pathology)
College Of Agriculture, OUAT, BBSR

2. Topic:
PL. PATH. 502 (Plant Virology)
(2+1)

3. NAME OF DISEASE
• Common names : Banana Bunchy Top
• Other names : Bunchy top or Curly top or cabbage top
or strangles disease.

4. BANANA BUNCHY TOP
• Bunchy top virus or Banana virus - 1 or Musa virus-1
• First reported from Fiji in 1889 in Cavendish varieties
• Around 1940, introduced into India from Srilanka through
cyclone
• Banana bunchy top virus is a ssDNA virus with single
isometric particles

5. BANANA BUNCHY TOP VIRUS (BBTV)
Virus Classification
Group Group II (ssDNA)
Family Nanoviridae
Genus Babuvirus
Species Banana bunchy top virus

6. OCCURRENCE
• World - Asia, Africa, Australia and South Pacific areas.
• India - Tamil Nadu, Kerala, Karnataka and Andhra Pradesh.
• The pathogen is not present everywhere bananas are grown,
but is present in most areas where the vector is also present.
These aphids are most likely native to Southeast Asia.

7. ECONOMIC IMPORTANCE
• Banana bunchy top disease is the most serious virus disease
of banana world wide.
• Diseased plants rarely produce fruit and when they do, the
fruit is stunted and twisted
• The banana bunchy top disease has had a huge impact on
the banana industry in Hawaii and Australia and among
other areas of the world.

8. • The disease was first seen on the Hawaiian island of Oahu in
1989 and by 2002, only 13 years later, it was a major disease
on four of the Hawaiian islands (Hawaii, Oahu, Kauai and
Maui).
• The movement of BBTV was mostly facilitated by human
movement of diseased plant material and banana aphids from
island to island.
• In the 1920s it almost completely destroyed the banana
growing industry in Australia.

9. SYMPTOMS
• Prominent dark green streaks on the petioles and midrib
along the leaf veins.
• Green streaks range from a series of dark green dots to a
continuous dark green line (Morse code).
• Marginal chlorosis and curling of leaves.
• Petioles fail to elongate.
• Leaves are reduced in size, chlorotic, stand upright and
become brittle and are crowded at the top (Bunchy top) and
shoe dark green streaks with 'J hook' shape near the midrib

16. TRANSMISSION OF BBTV
• BBTV can spread from one plantation to the next by means
of infected planting material and between plants with the
Banana aphid, Pentalonia nigronervosa (Hemiptera:
Aphididae).
• The immature aphid stages are small, reddish-brown to
almost black, oval shaped, and wingless

19. IDENTIFICATION OF PATHOGEN
• The virus is an isometric particle measure 20nm in diameter.
• It is ssDNA virus belonging to Nanoviridae family and
Babuvirus genus.
• The virus has multi component genome
• There are six circular single stranded genomes known to be
established.
• 1 kpb Length
• The virus concentration is more present in phloem.
• It is transmitted by infected suckers and banana aphid

21. DISEASE CYCLE
• Primary spread: Through infected plant suckers.
• S. I. By Banana aphid, Pentalonia nigronervosa
• Reservoir hosts: Cucumus sativus, C. melo, Catharanthus
roseus, Gynura aurantiaca, Colocasia esculenta, Amomum
subulatum and Elettaria cardamom.

23. • Aphids feed on the plant phloem tissues by injecting their
thin, flexible stylet into the epidermis of the plant tissue until
it reaches the phloem of the leaves.
• Then the aphid injects saliva and sucks the cell contents.
• This ingestion of viral components is done inadvertently by
the aphid.
• Vector transmission of the BBTV is circulative and non-
propagative, meaning that transmission of the virus occurs
from and to the phloem tissues and the virus does not
replicate within the aphid's midgut

24. MANAGEMENT
• Adaptation of strict quarantine measures.
• Use virus free planting materials.
• Remove and rouging of infected banana plants.Chop, dry and bury
the infected plants.
• Maintain clean, weed free field for early detection of infested suckers.
• Avoid banana cultivation in sugarcane and cucurbitaceous areas as
sugarcane mosaic virus or cucurbit mosaic virus can easily spread to
banana.
Cultural Method

25. • Vector control with systemic insecticides, viz., Phosphomidon
@ 1ml/1 or Methyl demeton @ 2 ml/ 1.
• Acetamiprid, Clothianidin, Dinotefuran, Imidacloprid,
Thiacloprid @ 2ml/l.
• Eradication of all infected suckers by spraying with kerosene
or by injecting herbicide
Chemical method