Bacterial leaf blight threatens second season paddy crop in Alappuzha

The Kerala Centre for Pest Management (KCPM) has issued an alert over the outbreak of bacterial leaf blight disease in paddy fields under five Krishi Bhavans in Alappuzha district.

Officials say the disease has been confirmed in Karuvatta, Nedumudi, Kainakary, Thakazhi, and Neelamperoor. The bacterial infection has been detected in fields undergoing second season paddy cultivation, between 35 and 85 days after sowing.

Officials say effective control of the disease is possible only if preventive measures are implemented at the initial stage. The bacterial cells accumulate in the plant’s vascular tissues, which absorb water and nutrients, thereby obstructing the upward movement of these vital resources. A visible symptom of the disease is leaf wilting. The current weather conditions are highly favourable for the disease’s spread. It can spread rapidly through rain, wind-borne contact between leaves, and water entering the fields, said a KCPM official.

The KCPM has recommended the following control measures: green cow dung can be tied in muslin cloth and placed near the water inlet, or cow dung slurry can be poured into the paddy field. Alternatively, bleaching powder can be placed in small muslin cloth pouches near water inlets at a rate of 2 kg per acre.

In the early stages of the disease, Bronopol 100% (Bionol) at 5 grams per 10 litres of water, mixed with 3 ml of a wetting agent such as Filwet or Teepol, can be sprayed. Ensure that the upper leaves are thoroughly wetted.

If the disease is more widespread, streptocycline (2 grams) and copper oxychloride (3 grams) can each be dissolved in 10 litres of water, along with 3 ml of Filwet/Teepol, and sprayed.

For farmers following organic methods, 20 grams of Pseudomonas fluorescens in 1 litre of water, or 20 grams each of Pseudomonas fluorescens and Bacillus subtilis in 1 litre of water, combined with 3 ml of Filwet per 10 litres of water, can be sprayed.

Nutrients like potassium and silica enhance disease resistance. Dissolve 100 grams of 13:0:45 foliar fertilizer, 25 ml of Silica, and 4 ml of Filwet/Teepol in 10 litres of water and spray. Avoid continuous water stagnation. Intermittently drying the field can reduce disease spread. However, in highly acidic soils, care must be taken to avoid excessive drying.