Abstract:
Betel vine Piper betle L. is largely grown as an important cash crop throughout
the tropical and subtropical regions in Bangladesh. Disease damage to the crop
is one of several known limiting factors. Foot and root rot of betel vine caused
by Sclerotium rolfsii is the most overwhelming disease which decreases the
production of betel leaf to a great extent. Management of foot and root rot
disease of betel vine caused by Sclerotium rolfsii was studied during cropping
season 2012-2013. The experiment was conducted in the Laboratory,
Department of Plant Pathology, Sher-e-Bangla Agricultural University (SAU),
Sher-e- Bangla Nagar, Dhaka. The field experiments were conducted in the
field of Malonchi upazila in Pabna district under natural condition. The
experiments were laid out in a Randomized Complete Block Design (RCBD)
with 3(three) replications. Initially 6 fungicides, 5 plant extracts and 2 bioagents
were
evaluated
for
their
efficacy
against
Sclerotium
rolfsii
by
an
in
vitro
test.
In in vitro experiment (cup method) Bavistin proved to be the best in
controlling the radial mycelum growth of Sclerotium rolfsii. Among them 3
fungicides, 2 plant extracts and 1 bio-agent were found promising and selected
for field evaluation against foot and root rot disease of betel vine. Treatment of
betel vine stem followed by spraying with 7 treatments comprising Bavistin,
Topgan, Tilt 250 EC, Garlic clove extracts, Neem leaf extracts, Trichoderma
harzianum based BAU-biofungicides and control were explored in the
experiment. A remarkable reduction of the severity of foot and root rot was
achieved by treating with fungicides. The lowest severity was found in the
Bavistin (0.71%) followed by Topgan (0.94%) whereas the highest disease
severity was recorded under the untreated control treatment (2.87%). The
highest yield was found in case of Bavistin which was 68.46% increased over
untreated control followed by Topgan (49.05%). Stem treated with Bavistin by
spraying at 7 days interval after inoculation minimized disease incidence,
severity and increased yield followed by Topgan. Garlic clove extract and
Trichoderma harzianum showed better performance in controlling foot and
root rot disease of betel vine compared to control. Among the ecofriendly
approach T. harzianum based BAU-Biofungicide increased 30.15% yield over
control
iii
Description:
A Thesis
Submitted to Faculty of Agriculture
Sher-e-Bangla Agricultural University, Dhaka,
in partial fulfillment of the requirements
for the degree of
MASTER OF SCIENCE
IN
PLANT PATHOLOGY
SEMESTER: JULY-DECEMBER, 2013