Economic threshold levels for black gram: aphids – 20 per 2.5 cm shoot length; pod borers – 10% of pods affected; spotted pod borer – 3 larvae per plant.
Pending expert review
Source
Crop Production Guide – Agriculture 2020 (Directorate of Agriculture, Tamil Nadu & Tamil Nadu Agricultural University (TNAU)), Blackgram – Crop protection, ETL, p. 140
Region
Tamil Nadu
Last updated
2026-11-04
Chemical pesticides: ask before you spray
The source lists insecticides and fungicides for black gram pests and diseases. Many are hazardous, and some may be restricted. Choose a product only with your local Agriculture Officer, and spray only after the pest crosses the threshold level.
Follow the instructions on the product label. Consult your local Agriculture Officer before use.
Pending expert review
Source
Crop Production Guide – Agriculture 2020 (Directorate of Agriculture, Tamil Nadu & Tamil Nadu Agricultural University (TNAU)), Blackgram – Pest & disease management, pp. 140–141
