Curcurbita Flashcards
Squash leaf curl
Squash leaf curl virus
Squash leaf curl
Squash leaf curl virus
Transmitted by whitefly, Bemisia tabici in a
semi-persistent (circulative) manner.
• The virus is not transmitted through seeds or by
mechanical means.
Squash leaf curl virus
Initial symptoms include mottling of interveinal
tissues and green vein banding.
• Plant may show severe leaf curling or cupping
and stunting.
SLC
Remove infected plants as soon as symptoms
are seed.
Remove weeds that serve as alternate host.
SLC
Phoma cucurbitacearum
Gummy stem blight
Leaf spots, mostly on leaf edges are light brown
and expand to the center of the leaf usually forming
a V or U shape lesion.
Older leaves become yellowish and die
Phoma cucurbitacearum
Stem lesions are light brown and often elongated
and can be found at or near the stem base usually
resulting from expansion of the leaf infection.
Phoma cucurbitacearum
Stem lesions are light brown and often elongated
and can be found at or near the stem base usually
resulting from expansion of the leaf infection.
Phoma cucurbitacearum
Fruit infection usually starts from the blossom
end.
May be seed-borne.
Cotyledons and young leaves are resistant but
become susceptible as they mature.
Phoma cucurbitacearum
Moisture and high relative humidity is more
important
for
disease
development
than
temperature.
• Spore are disseminated by rain splashes or
irrigation water.
Phoma cucurbitacearum
Namamarako
cucurbit aphid-borne yellows virus (CABYV)
Initial
symptoms
include
leaf
wrinkling,
downward cupping and mild yellow patches in
older leaves.
Cucurbit aphid-borne yellows virus
CABY
Young leaves show interveinal chlorosis ,extreme reduction in size.
In severe cases, plants become stunted and
may not bear fruit due to the reduction of the
number of female flowers produced.
CABY
The virus is spread in a persistent manner by 2 aphid
species, Aphis gossypii and Myzus persicae and by
grafting.
CABY
