EFFICACY OF DIFFERENT FUNGICIDES ON THE MANAGEMENT OF ALTERNARIA BLIGHT OF MUSTARD

Abstract

An experiment was done at Hajee Mohammad Danesh Science and Technology University, Dinajpur during the period of 2022-23 cropping season to explore the possibility of controlling Alternaria blight of mustard caused by Alternaria biassicae and A. brassicicola. A promising mustard variety BARI-14 was used in this experiment. In the field, three different fungicides viz., Rovral 50WP. Bavistin 50WP and Amister Top 325EC were utilized. The applications varied across plots: no application in the control plots, once, twice and thrice in the other plots. The Alternaria symptom was appeared on lower leaves at 14 to 17 days old plants and spraying were started from the time of disease initiation with 10 to 15 days interval. Among the treatments three times application of Rovral showed superior performance in controlling Alternaria blight of mustard. Rovral, applied thrice showed excellent efficacy, reducing disease incidence and spot size by 56.51% and 52.11%, and lowering plant infection percentages by 68.58%, 74.06%, and 64.60%. Rovral also performed well, when applied thrice in increasing the number of healthy plants, leaves, and pods by 63.34%, 57.48%, and 71.43%, with a yield boost of 52.2%. Bavistin, applied three times, reduced disease incidence , spot size by 56.13% and 48.75% and also reduced other infection percentages, increasing yield by 48.17%. Amister Top-3 spray lowered disease incidence, spot size, and infection percentages by 54.31%, 47.27%, 52.20%, 51.25%, and 51.70%, with a yield increase of 45.8%. Rovral-2 spray outperformed others, reducing disease incidence , spot size, and infection percentages, resulting in a 39.35% yield increase. In some cases, two times application of Rovral surpassed three times application of Amister Top in promoting plant and pod health and reducing infected plants. Bavistin 50WP, applied twice, showed better results than Amister Top 325EC but fell short of twice application of Rovral's performance. And among the fungicides Rovral showed better performance while Bavistin stood in the very next position and a lower performance was found by Amister Top in compare to others.