Management of Alternaria blight of Indian mustard through combo of seed treatment and foliar sprays of bioagent and fungicides

Abstract

Alternaria blight caused by Alternaria brassicae (Berk) Sacc. and A. brassicicola (Schw) Wiltshire is one of the most devastating disease on rapeseed-mustard causing major economic losses. The field experiments were conducted during 2017-18 and 2018-19 to evaluate combo of seed treatment and foliar sprays of bio-agents and fungicides. Treatment T8 i.e. ST with Thiram 2.5 g/kg seed + 3 spray of Nativo @ 0.05% was found most effective with minimum mean disease severity 13.27% followed by T2- ST with P. fluorescence @ 6.0 g/kg seed + 3 spray of Nativo @ 0.05% with severity 17.66%, T12- ST with Thiram 2.5 g/kg seed + 3 spray of Folicur @ 0.2% (21.40%), T6- ST with P. fluorescence @ 6.0 g/kg seed + 3 spray of Folicur @ 0.2% (24.05%), T9- ST with Thiram 2.5 g/kg seed + 3 spray of Propiconazole @ 0.1% (25.93%). Maximum yield (Kg/ha) and increase in yield was found in T8 1672.22 kg/ha and 70.05% respectively followed by T2 (1627.77; 65.63%), T12 (1594.44; 62.14%), T6 (1561.11; 58.75%), T9 (1544.44; 57.06%). The highest yield loss was avoided by T8 (41.19%) followed by T2 (39.55%), T12 (38.32%), T6 (37.01%), T9 (36.33%). The maximum cost benefit ratio was found in T9 (1:3.60) followed by T3 (1:3.38), T8 (1:2.48), T2 (1:2.32), T11 (1:2.03).