Bacillus thuringiensis subsp. kurstaki strain SA-12

The active substance consists of spores and protein crystals (delta-endotoxins) of the soil bacterium Bacillus thuringiensis var. kurstaki. Strain SA-12 is a highly effective biological agent that targets lepidopteran larvae selectively.

Once ingested by the pest, the toxin crystals dissolve in the alkaline gut environment. The activated toxins bind to specific receptors in the midgut epithelium, causing pore formation and tissue disintegration.

As a result, feeding stops almost immediately after ingestion. The insect becomes paralyzed and dies within a few days due to gut infection and starvation.

The product is safe for mammals, beneficial entomophages, bees, and humans, making it an excellent component for integrated pest management programs.

A major advantage of this strain is that target pests do not typically develop resistance to these bacterial toxins, allowing for repeated use without loss of efficacy.

Products based on the SA-12 strain are used against a wide variety of lepidopteran larvae (caterpillars). These include cabbageworms, diamondback moths, loopers, leafrollers, and various types of armyworms.

This bio-insecticide is effective against various pests affecting both field crops and horticultural crops, including fruit trees where it targets early-stage codling moth larvae.

The product is particularly useful for controlling pests on leafy vegetables, brassicas, and berries where low residue requirements are strictly enforced.

Maximum efficacy is achieved when targeting younger larval stages (instars I–III), which consume more leaf tissue and are more susceptible to the endotoxin.

Because the product acts via ingestion, uniform coverage of the foliage is essential for successful pest management.

Application rates depend on the specific pest density and the crop type. The prepared spray solution should be applied according to the manufacturer's label instructions.

Optimal timing for application is during the peak hatch of eggs. This prevents the larvae from reaching a size that can cause significant economic damage to the crop.

Applications should be made in the early morning or evening to avoid direct sunlight, as UV radiation can degrade the bacterial spores and reduce effectiveness.

Adding a spreader-sticker (adjuvant) is highly recommended to improve the retention of the product on waxy leaf surfaces, especially on crops like cabbage.

Re-application intervals are usually 7–10 days, depending on the pest pressure and the rate of new plant growth, which requires additional coverage.

Do not mix the biological product with chemical bactericides, as they can inhibit the viability of the Bacillus thuringiensis spores.

While the product is environmentally safe, users should wear personal protective equipment such as gloves and a mask to prevent irritation.

In case of contact with skin or eyes, flush thoroughly with clean water. Keep the product stored in a cool, dry place away from direct sunlight.

Storage conditions must be strictly followed to ensure the titer of spores remains stable over time and the product retains its biological activity.

Since the insecticide has no systemic action, ensure that all parts of the plant, including the undersides of leaves, are thoroughly sprayed.