Integrated Pest Management Schedule for Vegetables - National ...

DISEASEMANAGEMENTTOMATOAlternaria Blight (Alternaria solani,A. alternata f.sp. lycopersici)SymptomsIrregular leaf spots mostly appear from marginalportion of leaves. In many tomato cultivars, symptomsare V shaped and progress towards midrib. Theselesions are having prominent yellowing on their outermargin due to host specific toxin produced by thepathogen. Mostly disease appears in vegetative phaseof plant growth before flowering. Symptoms of earlyblight appear on all above ground parts of the plant.Pre and post emergence damping off in seedbeds alsooccurs.Field sanitation by plucking the lower leaves andburning of infected crop debris.Summer ploughing to increase the desiccation ofpathogen and infected plant parts.Minimize relative humidity in plant canopy forpreventing the infection.Two spray of Chlorothalonil @0.2% at 8 daysinterval is effective against the disease but spraymust be started soon after infection on floral part.Late Blight (Phytophthora infestans)SymptomsBlight appears on foliage as light-pale green watersoaked dead area. The lesions are wet in morning anddried, shriveled in daylight. It enlarges rapidly untilentire leaves are killed and exposing all the fruits forinfection. In moist and cloudy weather a downy whitefungus develops near the outer margin of lesion onunderside of the leaves. Green and ripe fruit affectedby the blight appear as greenish brown and internaltissues become spongy with bad odour.Elongated & concentric on stem/fruit lesions/ foliage due to alternariaManagementCrop rotation with non-solanaceous host isessential for effective reduction of inoculum.Healthy seeds should be collected only fromdisease-free fruits.Phytophthora blight on green fruits