Abstract:
An investigation was conducted on the citrus plants at the citrus orchard of Sher-eBangla
Agricultural University, Dhaka, during the period of from April to
September 2008 to find the effect of fungicides in controlling the scab and die
back of citrus. The citrus plants were sprayed with seven fungicides namely,
Cupravit 50WP (0.7%), Bavistin 50 WP (0.1 %), Rovra) 50WP (0.2%), Ridornil
MZ-72 (0.2%), Tilt 250EC (0.05%), Champion 77 WP (0.2%) and Dithane M-45
(0.3%). The performance of the fungicides varied significantly in reducing the
disease incidence and severity of citrus scab (Elsinoe fawcettiiy and die-back
(Colletotrichum gloeosporioides) compared to control. Incidence of scab (leaf and
fruit) was remarkably reduced respectively by Rovral 50WP and Champion 77
wp. after the end of sixth spray. Disease incidence of die back after the end of
sixth spray was potentially reduced by Dithane M-45 followed by Bavistin 50 WP.
The highest reduction of leaf scab severity was performed by Rovra) 50WP
(86.17%) followed by Champion 77 WP (81.76%) and Dithane M-45 (77.53%).
The highest reduction of fruit scab severity was performed by Champion 77 WP
(82.35%) followed by Dithane M-45 (76.60%) and Rovral 50WP (70.56%). The
highest reduction of die back severity was shown by Dithane M-45 (69.78%)
followed by Bavistin 50 WP (64.48%) and Tilt 250 EC (58.96%). Thus Rovral 50
WP and Champion 77 WP can be used for controlling scab of citrus while Dithane
M-45 can be used for controlling both scab and die back of citrus.
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 (MS)
IN
PLANT PATHOLOGY
