Rabi sorghum occupies significance importance as a staple cereal food crop for many poor families.
Apart from moisture stress, diseases and pests also pose additional threat during the crop's growth period.
Most destructive
Among the diseases, charcoal rot is the most destructive one.
The disease is prevalent in both red and black soils and causes grain yield losses from 30 per cent to 90 per cent.
The infestation is caused by a fungus. Infected plants fall on the ground due to weakened stalk.
Outward symptom
Characteristic outward symptom in the field is lodging, premature drying of stalks, root rot and reduction in filling up of grains. This often occurs in the driest part of the field.
The fungus has a very wide host range like maize, soybean and several other crops and survives during off-season in the form of sclerotia
Sclerotia germinate under high soil temperature conditions of 30 degree Celsius and lower soil moisture.
High soil moisture stress and high temperature is conducive for development of the disease.
Disease management
— Avoid soil moisture stress by mulching, adjusting dates of sowing.
— Early sowing, long crop rotation, soil solarisation, use of bio-control agents, balanced fertilizers, deep sowing, wider spacing, optimum plant population reduces the incidence.
— Apply minimum dosage of nitrogen fertilizers. Adopt intercropping than sole cropping
— Grow drought tolerant, lodging resistant, and non-senescing types of sorghum like CSV 17, SPV 462 etc.
— Soil fumigation with methyl bromide reduces the pathogen load.
— Seed treatment with Trichoderma harizianum or T. viride at 4gm/kg seed were effective in reducing percent incidence.
—Application of neem cake, safflower cake and mulching with wheat straw reduces the disease.
Mallikarjun Kenganal
Byadgi, A. S.
& Benagi, V. I
Department of Plant Pathology, University of Agricultural Sciences Dharwad
