This ppt have all details about bacterial blight of cotton

6.  1. Seedling blight –
the earliest symptoms of
the disease is seen in
the cotyledon of
germinating seeds.
Minute water-soaked
spots appear on the
under surface of the
cotyledons and
ultimately collapse and
die.

7. Often the disease spreads along the
edge of vein,hence calledveinblightor
blackvein.
 2.Blackarm
Symptoms–lesions on stem,
petioles, and fruiting branches are
dark brown to stooty black.
 Affected stem show crackes and
gummosis and are easily broken by
wind or there may be girdling and
death of affected organs. These are
called black arm

8. 3. Angular leaf spot - On the
leaves, scattered small dark-
green, water-soaked, areolate
spots, form measuring 1–2 mm
on the lower surface, which
appear translucent against
transmitted light.
 The spots increase in diameter to
5 mm, become angular (due to
leaf veination), brown and later
turn dark brown to blackish,
becoming visible on the upper
surface

13. The bacterium survives on infected, dried plant debris in soil for several
years.
 The bacterium is also seed-borne and remains in the form of slimy
mass on the fuzz of seed coat.
 The bacterium also attacks other hosts like Thumbergia thespesioides,
Eriodendron anfructuosum and Jatropha curcus.
 The primary infection starts mainly from the seed-borne
bacterium.
 The secondary spread of the bacteria may be through wind, wind
blown rain splash, irrigation water, insects and other implements.

15. Grow resistant varieties like Sujatha,
1412 and CRH 71.