SOLID WASTE MANAGEMENT SYSTEM OF FENI PAURASHAVA, BANGLADESH.pdf
S.mythili 2015021085-verticillium wilt of brinjal
1. COLLEGE OF AGRICULTURAL TECHNOLOGY
(Affiliated to Tamil Nadu Agricultural University, Coimbatore-3)
Kullapuram (Po),ViaVaigai Dam, Theni-625 562
VERTICILLIUM WILT OF BRINJAL
Submitted by Course teacher
S.MYTHILI Dr.Parthasarathy.S
2015021085 Assistant Professor (Plant Pathology)
2. Verticillium wilt of brinjal
Verticillium dahliae and Verticillium albo-atrum
Pathogen
3. History
The disease was first reported and described in North
America in the late 1940 and erroneously attributed to
V. albo-atrum. Its true identity was recognized as
V. dahliae in 1970.
4. ECONOMIC IMPORTANCE
• Verticillium dahliae and V. albo-atrum cause
economic losses in crops in temperate regions of the
world and hence are the most studied species.
• The disease cycle of both species is similar in most
aspects except that V. dahliae produces microsclerotia
and V. albo-atrum produces melanized mycelia for
survival between crops.
5. Host and Distribution
• Verticillium affect more trees, shrubs and vegetables.
• Some of the host plants are Tomato, Cotton, Potato
etc.,
• It is worldwide distributed disease.
• Some of the countries are China, Armenia, Hebei,
Henan, Shanxi etc.,
6. Symptoms
• Verticillium dahliae can infect eggplant plants at any
growth stage.
• Symptoms include yellowing and drooping of leaves
on a few branches or on the entire plant.
• The edges of the leaves roll inward on infected plants
and foliar wilting ensure.
• The foliage of severely infected plants turns brown
and dry.
• Chlorosis observed in the middle between the veins.
• V shaped chlorosis on the tip of the leaf
8. • Plants infected early in the season can be severely
stunted with small leaves that turn yellow-green.
• Subsequently, the dried leaves and shriveled fruits
remain attached to plants that die.
• pinkish discoloration of the vascular tissue is visible
when the roots and lower stem of a wilted plant are
cut longitudinally.
9. • Root rot also cause similar foliar symptoms.
• However, root rot cause extensive browning and
rotting of the root cortex, while the roots of V.
dahliae-infected egg plant show no external
discoloration or decay.
14. Pathogen
• Verticillium dahliae belongs to the fungal class
Deuteromycetes (Fungi Imperfecti) a group of fungi,
which do not have a known sexual stage.
• The vegetative mycelium is hyaline, septate, and
multinucleate.
15. • The nuclei are haploid in culture. Conidia are ovoid
or ellipsoid and usually single-celled.
• They are borne on phialides, which are specialized
hyphae produced in a whorl around each
conidiophore.
• Each phialide carries a mass of conidia. Verticillium is
named for this verticillate (=whorled) arrangement of
the phialides on the conidiophore.
• The fungus forms microsclerotia in dying tissue,
which are masses of melanized hyphae.
16. Pathogen
• Verticillium albo-atrum having larger conidiophores
with a dark swollen phase, a larger conidia having
one septation, dark thickened resting mycelium and
swollen hyphae.
17. Mode of spread
• Primary spread- Soil borne chlamydospores and
dormant mycelium from plant debris.
• Secondary spread- water borne conidia.
18. Management
Cultural control
• Do not leave crop remains on the field or add them to
the compost pile, this encourages future infections.
• Crop rotation with non susceptible grasses and grains
is of value, 4 to 5 year crop rotation intervals should
be followed in order for pathogen populations to drop
as infected plant residues decompose.
• Do not crop rotate with tomato or potato. They are
very susceptible hosts.
19. Biological control
• Double Nickel LC at 0.5 to 4.5 pints/A for soil
application on 14 to 28 day intervals. It can be
applied at the day of harvest.
Chemical control
• Soil application and foliar application with Benlate
(0.1%) is effective in reducing the wilt disease.
• Vapam at various rates also used.
