The golden fibre of eastern India — grown across 700,000 hectares of West Bengal, Bihar, and Assam in the humid monsoon months; the basis of the sacking, textile, and handicraft industries.
5 Major Threats and Their Control
For educational purposes only. Recommended crop varieties are location-specific. Always verify chemical and variety recommendations with your local KVK or State Agriculture Department.
1. Yellow Mite
(Polyphagotarsonemus latus)
The Threat:
- The yellow mite is near-microscopic and the most economically destructive jute pest in West Bengal and Assam.
- It settles on the growing tip and very young leaves, sucking cell contents and injecting toxic compounds.
- Causes “telia” — leaves at the growing tip become bronzed, brittle, and severely distorted.
- Reduces plant elongation and the quality of fibre from affected internodes.
- In severe infestations, the growing tip stops elongating entirely.
- Losses can reach up to 25% of fibre yield.
The Solution:
- Spray Dicofol 18.5 EC (Acaricide — Organochlorine) @ 2 ml/litre or Abamectin 1.9 EC (Acaricide / Insecticide — Avermectin, IRAC Group 6) @ 1 ml/litre at first symptom detection, ensuring coverage of the growing tip and young leaves.
- Early sowing in March–April establishes the crop before peak mite populations in June, reducing infestation severity at the vulnerable growing tip stage.
2. Stem Rot
(Macrophomina phaseolina)
The Threat:
- Stem rot attacks the root and stem base during the pre-monsoon dry period of May–June, when soil moisture is lowest and the fungal pathogen is most active.
- Plants wilt and fall in patches just before the monsoon breaks.
- Damage is particularly severe because the crop has not yet reached the height needed for quality fibre production.
- Post-monsoon waterlogging reactivates surviving inoculum, extending the damage window.
The Solution:
- Treat seed with Carbendazim 50 WP (Systemic Fungicide — Benzimidazole, FRAC Group 1) @ 2.5 g/kg.
- Avoid water stress at the seedling stage, as dry conditions favour fungal activity.
- Maintain field drainage channels to prevent post-monsoon waterlogging that reactivates the pathogen in surviving root tissue.
3. Semilooper Caterpillar
(Anomis sabulifera)
The Threat:
- The semilooper is a geometrid-type caterpillar that defoliates jute by feeding on leaf margins inward, producing characteristic semicircular notches.
- In August–September, warm and humid conditions allow rapid population buildup.
- A single uncontrolled larval generation can strip the entire upper canopy, reducing photosynthesis and cane height increment during critical fibre development.
- Populations can escalate from undetectable to defoliating levels within 7–10 days.
The Solution:
- Spray Quinalphos 25 EC (Contact Insecticide — Organophosphate, IRAC Group 1B) @ 2 ml/litre at 5 caterpillars per plant — the Economic Threshold Level established by ICAR-NIRJAFT.
- Apply HaNPV (Biological Insecticide — Baculovirus) at the first larval instar stage for biological control, before larvae become large enough to cause rapid defoliation.
4. Flooding and Waterlogging
The Threat:
- Annual flash floods in the Gangetic-Brahmaputra delta cause:
- Physical stem damage from strong water currents.
- Root disease due to anaerobic soil conditions.
- Complete crop loss in low-lying fields.
- In Assam and north Bengal, flooding is near-annual for fields below embankment level.
- Timing (July–August, peak crop height) results in loss of fibre quality and length through stem staining and tip damage.
The Solution:
- Grow flood-tolerant varieties recommended by ICAR-NIRJAFT, Kolkata — JRO-524 for the olitorius (tossa jute) type, suitable for flood-prone areas.
- Construct and maintain field bunds to control flood depth and duration.
- Select elevated fields for jute cultivation wherever possible.
5. Nutrient Deficiency (N, P, K)
The Threat:
- The heavily leached alluvial soils of the jute belt, continuously inundated by annual flooding and intense monsoon rain, are chronically depleted in nitrogen, phosphorus, and potassium.
- Nitrogen deficiency: produces thin, short stalks with poorly developed bast fibre bundles.
- Phosphorus deficiency: reduces root development and overall plant vigour.
- Potassium deficiency: lowers cellulose content of the fibre, making it weak and brittle.
- Combined deficiencies result in both low yield and low fibre quality — a double commercial loss for the farmer.
The Solution:
- 80 kg Nitrogen (N), 17.5 kg Phosphorus (P), and 33.3 kg Potassium (K) per hectare is generally recommended.
- Apply chemical fertilizers on the basis of soil test.
- Supplement with FYM (Organic Fertiliser) @ 5 t/ha or incorporate dhaincha (Sesbania bispinosa) green manure in the preceding fallow season.
- Dhaincha fixes 60–80 kg nitrogen per hectare.
- Improves soil structure and water-holding capacity for the subsequent jute crop.
Ph.D. in Agricultural Engineering.