Abstract:
Early blight is one of the most common and devastating disease of potato
plant which is caused by the fungus, Alternaria solani. The efficacy of six
commercial chemical fungicides viz. Bicozeb 80 WP (Mancozeb), Rovral
50WP (Iprodione), Sazid 70 WP (Mancozeb + Metalaxyl 7%), Win 77WP
(Copper Hydroxide), Pipertax 50WP (Copper Oxychloride) and Tilt 25 EC
(Propiconazole) were tested against early blight disease of potato in field
condition during 2016-2017 in Sher-e-Bangla Agricultural University,
Dhaka. The experiment was conducted following RCBD design with three
replications. The finding showed that, all fungicides significantly reduced
the early blight disease incidence and severity as well as increased the yield
of potato in compared with control under field conditions. The maximum
reduction of plant infection 86.95%, leaf infection 86.83% and disease
severity 86.70% were observed at 80 days after planting by the application
of Bicozeb 80 WP. The maximum yield increased by 121.18% when the
field was applied by Bicozeb 80 WP against early blight disease of potato.
Rovral 50 WP (Iprodione) also showed better performance in controlling
disease. Thus, the present study revealed that, application of fungicides viz.
Bicozeb 80 WP (Mancozeb) have shown significant effect and proved to be
cost effective for the management of early blight disease of potato in field
condition.
