MANAGEMENT OF SCAB AND DIE-BACK OF CITRUS (Citrus limon L.) THROUGH BIOAGENT, PLANT.EXTRACTS AND FUNGICIDES

Abstract

A research work was conducted on the standing citrus plant raised at .. citrus orchard in Sher-e-Bangla Agricultura1 University, Dhaka, during the period from May to September 2005 to investigate . the effect of bioagent, plant extracts and fungicides in controlling the scab and die back of citrus. One bioagent (Trichoderma harzianum T22), three plant extracts viz. Bishkatali (Polygonum hydropiper), Garlic (Allium sativum) and Neem (Azadirachta indica) and five fungicides viz. Dithane M-45 (0.3%), RidQmil MZ·72 (0.2%), Bavistin 50 WP (0.1%), .Champion 77 WP (0.25%) and Bordeaux mixture (1%) were applied for controlling scab and die back of citrus. The highest reduction of the scab severity (PDI) was performed by Champion 77 WP (72.72% leaf scab and 83.98% fruit scab) followed by, Bishkatali (67.54% and 79.99%), Bordeaux mixture (66.26%, and 72.01%) and Trichoderma harzianum T22(62.36% and 63.34%). The highest reduction of die-back severity (PDI) was resulted by Dithane M-45 (73.46%) fallowed by Neem extract (67.34%), Bordeaux mixture (59.19%) and Trichoderma harzianum T22 . (57.67%).Thus, the Champion 77 we (0.25%) could be used for controlling scab of citrus while Dithane M-45 (0.3%) for die-back .and ' Bordeaux mixture for both scab and die-back of citrus.