Abstract:
Incidence and severity of sclerotium root rot disease of sugarbeet was investigated at
Sher-e-Bangla Agricultural University (SAU) and Bangladesh Sugarcrop Research
Institute (BSRI) campus during January to March 2019. From the survey study it revealed
that, the highest disease incidence (21.6%) was observed at BSRI farm, Iswardi in
compared to SAU field (19.4%) and the disease severity was higher at BSRI campus
(7.73%) compare to SAU campus (5.51%). The lab experiment was conducted for invitro
management
of
sclerotium
root
rot
disease
of
sugarbeet
through
chemical,
botanical
and
biological
means
during
April
to
december
2019.
Seven
fungicides
viz.
Amister
Top
325
SC,
Acibin
28 SC, Tilt 250 EC, Ridomil Gold, Dithane M-45, Cabrio Top 55 WG,
Benda 50 WP, one plant extract (Neem leaf) and two bio- agents (Trichoderma
harzianum and Pseudomonus fluorescens) were evaluated for their efficacy against
Sclerotium rolfsii. The selected chemical fungicides and neem leaf extract were evaluated
following by cup method and two bio-agents were evaluated through dual culture
method. Among the tested chemical fungicides, Cabrio Top 55 WG and Acibin 28 SC
gave the better performance in controlling the radial mycelial growth of Sclerotium
rolfsii. Amister top showed better Performance in reduction of radial mycelial growth
(inhibition 70% over control) followed by Tilt 250 EC, Benda, Ridomil Gold, and
Dithane M-45 (inhibition 64.78%, 64.11%, 18.56%, 14.44% over control respectively) at
4 days after inoculation. Neem leef extract was not found satisfactory result in reducing
the growth of fungus in in-vitro. Between two bio-agents Trichoderma harzianum (%
inhibition 42.77% over control) showed better performance in controlling Sclerotium root
rot disease of sugarbeet compared to Pseudomonus fluorescens (% inhibition 27.60 %
over control )in reduction of radial mycelial growth of S. rolfsii. In this study, the
potentiality to cause sugarbeet root rot disease caused by Sclerotium rolfsii was also
confirmed through pathogenicity test. However, from the findings of the in-vitro study, it
may be concluded that among the selected chemical fungicides, Acibin 28 SC, Cabrio top
55WG and bio-agents Trichoderma harzianum can be suggested for field trail for
management of sclerotium root rot disease of sugarbeet.
Description:
A Thesis
Submitted to the 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
