Assessing the Effectiveness of Newly Developed Fungicides in Managing Rice Blast Disease

Abstract

Rice blast, which is caused by the fungus Magnaporthe oryzae, is a highly destructive disease that poses a significant threat to rice cultivation. It results in considerable crop damage, affecting both the yield and quality of rice. This makes rice blast a major concern for farmers and a significant issue in terms of food production. These studies were carried out at Bangladesh Institute of Nuclear Agriculture (BINA), Mymensingh with the aim to manage rice blast disease by means of different fungicides under in in-vitro and field conditions. In-vitro bioassay of six chemical fungicide(s) viz. Amister top 325SC, Seltima, Nativo 75 WG, Filia 525 SE, Avalon 27SC and Trooper 75 WP was done against Magnaporthe oryzae following poison food technique in the Plant Pathology Lab of BINA. The maximum mycelial growth inhibition (73.43%) of Magnaporthe oryzae was obtained by Avalon 27SC (Picoxystrobin 6.70%+ Tricyclazole 20.33%), Nativo 75WG (Tebuconazol 50% + Trifloxistrobin25%) and Seltima (Pyrachlostrobin 10%) at 0.0125% concentrations and 100% growth inhibition was obtained by all the six fungicides at 0.1% and 0.5% concentrations. In vivo evaluation of five fungicides viz. Amister top 325SC, Seltima, Nativo 75 WG, Filia 525 SE and Avalon 27SC against rice blast was carried out in research plot of the Plant Pathology of BINA. From the result, it was concluded that all the fungicides were effective in controlling leaf blast but Avalon 27SC (Picoxystrobin 6.70%+ Tricyclazole 20.33%) @ 0.2% was more effective among other fungicides, showing least leaf blast severity mean at three time interval (1.00, 1.33 and 1.46), least incidence (11.90%, 15.08%, 16.67%), and the highest grain yield (7.58 t ha-1).