Pests and diseases

Scale insects

పొలుసు పురుగు

Insects and mites

The advice below comes from each crop's guide — every item shows its source, region and date. It is pending expert review; ask your local officer whether it suits your area.

Colocasia

  • Leaf blight

    Leaf blight can cause up to 50% loss in severe cases. Non-chemical measures in the source: field-resistant varieties (Muktakeshi, Jankhri), early planting to avoid heavy monsoon rain, healthy planting material, removing self-grown taro plants, and treating seed tubers with Trichoderma viride. Fungicide sprays and chemical dips for aphids, mealybugs and scales are also listed — ask your officer before using them.

    Pending expert review
    Source
    Crop Production Guide – Horticulture Crops 2020 (Directorate of Horticulture and Plantation Crops, Tamil Nadu & Tamil Nadu Agricultural University (TNAU)), Taro – Leaf blight management, p. 146
    Region
    Tamil Nadu
    Last updated
    2026-11-04

Turmeric

  • Chemicals: ask before you use

    The source also lists chemical rhizome treatments and sprays for rhizome rot, scales, thrips, nematodes and leaf spots. Choose any product only with your local Agriculture Officer.

    Follow the instructions on the product label. Consult your local Agriculture Officer before use.

    Pending expert review
    Source
    Crop Production Guide – Horticulture Crops 2020 (Directorate of Horticulture and Plantation Crops, Tamil Nadu & Tamil Nadu Agricultural University (TNAU)), Turmeric – Transplants technology; plant protection, pp. 171–173
    Region
    Tamil Nadu
    Last updated
    2026-11-04

Ber

  • Fruit fly and scales: non-chemical measures in the source

    Fruit fly: collect fallen and infested fruits and bury them under a thick layer of soil; plough between trees to expose pupae; use methyl eugenol lure traps (25/ha); neem oil 30 ml/l is also listed. Scale insects: prune and burn affected parts. Chemical sprays for black leaf spot and powdery mildew are also listed — ask your officer.

    Pending expert review
    Source
    Crop Production Guide – Horticulture Crops 2020 (Directorate of Horticulture and Plantation Crops, Tamil Nadu & Tamil Nadu Agricultural University (TNAU)), Ber – Plant protection (pests), p. 40
    Region
    Tamil Nadu
    Last updated
    2026-11-05

Rose

  • Pests: non-chemical measures in the source

    Rose chafer beetle: hand-pick the beetles during the day and destroy them. White grub: set up a light trap to attract the adult beetles. Red scale: rub off the scales with cotton soaked in kerosene, and cut and burn affected branches. Neem oil 3% is listed for thrips, aphids and leafhoppers.

    Pending expert review
    Source
    Crop Production Guide – Horticulture Crops 2020 (Directorate of Horticulture and Plantation Crops, Tamil Nadu & Tamil Nadu Agricultural University (TNAU)), Rose – Pests (non-chemical measures), pp. 248–249
    Region
    Tamil Nadu
    Last updated
    2026-11-05

Tea

  • Pests: non-chemical measures in the source

    Stem borer: locate the frass mat at the base of the bush, remove it, and push a thick wire into the bore hole to kill the larva. Tea mosquito bug: monitor regularly and remove alternate hosts such as neem, cashew and guava nearby. Neem-based azadirachtin is listed for thrips and mites. Chemical options for scales, thrips, aphids, mites, tea mosquito bug and blister blight are also listed — ask your officer.

    Pending expert review
    Source
    Crop Production Guide – Horticulture Crops 2020 (Directorate of Horticulture and Plantation Crops, Tamil Nadu & Tamil Nadu Agricultural University (TNAU)), Tea – Plant protection, p. 195
    Region
    Tamil Nadu
    Last updated
    2026-11-05

Coffee

  • Pests and diseases: non-chemical measures in the source

    White stem borer (Arabica under poor shade): keep optimum shade; trace and uproot infested plants in March and September; pheromone traps (25/ha) if severe; rub off loose scaly bark. Berry borer: harvest on time and thoroughly, pick up gleanings and leftover berries, remove off-season berries, avoid excess shade, prune for ventilation, and dry berries to the right moisture (parchment 10%, Arabica cherry 10.5%, Robusta cherry 11%). Shot-hole borer: prune affected branches. Scales and mealybugs: release Cryptolaemus beetles (300 per acre). Black root rot: dig out and burn infected bushes, trench around the spot, and do not replant for 18 months. Chemical options for these and for rust, black rot and collar rot are also listed — ask your officer.

    Pending expert review
    Source
    Crop Production Guide – Horticulture Crops 2020 (Directorate of Horticulture and Plantation Crops, Tamil Nadu & Tamil Nadu Agricultural University (TNAU)), Coffee – Plant protection, pp. 199–200
    Region
    Tamil Nadu
    Last updated
    2026-11-05