Management of leaf spot and flower blight of marigold caused by Alternaria tagetica (Shome and Mustafee) under field condition

Abstract

Leaf spot and flower blight caused by Alternaria tagetica (Shome and Mustafee) is one of the important diseases of marigold, which causes upto 50 to 60% losses in yield. In this present investigation, different fungicides, botanicals and bio-agents were evaluated under field condition. The results revealed that, Hexaconazole (0.1%) was found effective in reducing the percent disease index (32.15) on leaves and (33.76) on flower in all three sprays and getting higher yields (6.96 t/ha) followed by Mancozeb (0.2%) with PDI of (34.53) on leaves and (35.45) on flower with yield of (6.81 t/ha) as compared to control with (85.02 and 86.11 PDI) on leaves and flower respectively with yield of (4.26 t/ha). Among botanicals, Nimbicidin (0.5%) was effective in minimizing the percent disease index (14.80) on leaves and (16.81) on flowers and yield (4.81 t/ha). Trichoderma harzianum (5g/l) was effective in minimizing the percent disease index (17.07) on leaves and (17.37) on flowers and recorded yield (5.26 t/ha).