In this article we will discuss about how to control diseases of jute.
1. Seedling Blight:
This disease is caused by a fungus Marcophomina phaseoli. The fungus being seed-borne in nature, seedling may initially develop black lesion on cotyledons which rot and wither, the tender stem then dries turning brown. Ultimately the seedlings die and the field look bighted.
2. Root Rot:
This disease is also caused by M. phaseoli. Root rot infected plants show wilting as the first recognizable symptom. Tips of the affected plants droop and the colour of the stem gradually turns brown. Finally, the plant looks dry and withers completely. An infected root shows rusty brown colouration while healthy, roots are light yellow to buff coloured.
3. Stem Rot:
This disease is caused by M. phaseoli. Though the disease is denoted by stem rot, infection starts from leaves. The pycnospores of M. phaseoli fall on leaf surface germinate and the hyphal system penetrates the leaf tissue causing necrosis. The disease spreads towards the petiole and through it reaches the node of the stem. The node becomes black and infection patch spreads upwards and downwards. Minute black dot-like bodies develop on the stem and leaf.
4. Collar Rot:
This disease is also cause by M. phaseoli. The collar region of the plant, viz., 4-6 inches of the stem from the base is affected. A brownish black scar-like lesion is developed which may encircle the stem.
Control Measures:
Seed treatment for 10 minutes in a closed container with captan at the rate of 5 g/kg of seed. Apply lime and potash in areas with red and or acid soils. Spray Carbendazim (Bavistin) at the rate of 1 g/kg of water at the first appearance of symptoms.
5. Anthracnose of Capsularis:
This disease is caused by Colletrotrichum corchorum. Tiny, moist, brownish black spots appear on the stem which later coalesce to form a larger necrotic lesion. In an advanced stage of the disease, the necrotic spots become dark, dry and cankerous. When pods are attacked, these turn brown and shrivel.
Control Measures:
Seed treatment with Captan at the rate of 5 g/kg of seeds. Spray the crop twice a week with 0.2% copper oxychloride (Blitox) solution.
6. Anthracnose of Olitorius:
The causal organism is colletotrichum gloeosporiodes. At about three months stage of the crop many dark spots become visible on the stem. When the disease is severe, necrosis goes deeper, spots coalesce to from canker and yield is affected.
Control Measures:
Limiting application of nitrogen to 20 kg per hectare has been found to restrict the incidence of the disease. Spray the crop once a week with cooper oxychloride such as Blitox or fytolan 0.2% since the first appearance of the disease.
7. Stem Gall:
The disease caused by Physoderma corchori. The disease is found on late sown olitorius crop subject of submergence in low lying areas during monsoon. Galls may be initially green, but gradually turn pink to brown and finally rusty brown. Each infected plant may have innumerable galls, some of which coalesce to form a larger blister with lacerated fibre. Finally, the dead plants turn into black sticks.
Control Measures:
Avoid submerged conditions. Grow capsularis types in such areas.
In addition to above important disease there are several other diseases like Hoogli wilt, soft rot, black band or die-back, leaf mosaic, shooty mould of pods etc. of minor importance.
8. Root- Knot Nematode:
The attack of root-knot nematode is more the capularis jute than on olitorius. As a result of their attack, the roots become swollen and uptake of nutrients from soil becomes less. Leaves appear light green and dull in appearance.
Control Measures:
Apply Nemagon as preplant at the rate of 37.5 per hectare in irrigation water.