Influence of temperature, inoculum potential and wetness duration on development of anthracnose disease of strawberry

The influence of temperature, inoculum potential and wetness duration was studied on the development of anthracnose disease on leaves, green fruit and ripe fruit of strawberry. The disease produced characteristic symptom of brown to black necrotic lesions on leaves, green fruits and ripe fruits causing blightening of leaves and fruit rot. A temperature of 25°C was significantly more favourable for the development of disease on leaves (5 days), green fruits (6 days) and mature fruits (3 days) of strawberry than 15°C and 30°C. A significant higher PDI (Per cent Disease Index) was recorded on leaves, green fruit and mature fruit at 25°C after 9 days of inoculation. There was no disease development at 15°C even after 9 days of incubation. The inoculum strength of 10⁷ spores/ml was found significantly better than 10⁴, 10⁵ and 10^s spore/ml in the development of disease on leaves (5 days), green fruit (5 days) and mature fruit (3 days). A wetness duration of 24 hours significantly favoured the more disease development on leaves (5 days), green fruit (6 days) and mature fruit (3 days) than 0, 8, 12 and 16 hours. The ripe fruit were more susceptible than leaves and green fruit.