Bacillus Thuringiensis: biological larvicide

In the organic garden only products of organic or natural origin should be used , avoiding toxic pesticides, which are harmful to the environment and to those who will later eat the vegetables grown. Among the organic insecticides a very interesting product is bacillus thuringiensis.

It is a specific product against certain types of parasites, in particular it is effective against moth caterpillars They devour leafy vegetables like cabbage. The fact that it affects specific classes of insects is a great advantage of this insecticide. Indeed, the bacillus thuringiensis is very selective: This allows us to defend the vegetables without hitting other beneficial garden insects, such as bees.

The bacillus is a bacterium that affects the insect’s digestive system , there are several strains that can be useful against different parasites. The most used in the garden is bacillus thuringiensis variety Kurstaki which is sufficient to affect the aforementioned Lepidoptera larvae.

Contents [Ocultar]

  • insecticidal action

    • Non-toxic natural insecticide

  • Bacillus thuringiensis strains

  • How to use Bacillus thuringiensis

    • Where to find bacillus thuringiensis


The action of the insecticide

Baciullus thuringiensis is a bacterium, a unicellular organism. Its particularity is to be sporadic : under certain external conditions, the bacterium forms a spore as a whole and releases it. In this way, the bacillus takes on a more resistant form.

Together with the spore, a crystal is released, which has an insecticidal action: when ingested by insect larvae, it becomes a toxin and blocks the digestive system causing the death of the caterpillar.

There are three main strains of bacteria:

  • kurstaki

  • Tenebronis

  • Israelelensis.

Different strains of Bacillus thuringiensis are effective against different types of insects and therefore have different uses in the orchard and organic garden, as discussed below.

Among the various organic insecticides, this bacterium is particularly valuable for its selectivity, in fact it does not create problems for pollinating insects or ladybugs.

Non-toxic natural insecticide

Being an entomopathogenic bacterium, this insecticide is completely natural and is therefore a treatment authorized in organic farming which does not lead to toxicity problems or environmental consequences.

Unlike most pesticides on the market, Bacillus thuringiensis does not harm humans, wildlife and, as already mentioned, beneficial insects. Garden friends, like ladybugs, which eat pests, or bees, which pollinate flowers, can rest easy.

The bacterium of kurstaki varieties works by blocking the digestive system of lepidopteran larvae (butterflies and moths), killing these insects by paralysis. For this reason, it can be used in organic gardening without having to worry about it.

Bacillus thuringiensis pairs

There are several strains of this particular species of spore-forming bacteria.

The most interesting in organic farming among the types of bacillus thuringiensis is undoubtedly the BTK (Bacillus Thuringiensis Kurstaki) , for it is the one which affects the larvae of most insects injurious to the garden, fruit plants and orchards. Its effectiveness is mainly against Lepidoptera , such as guinea fowl, moths, moth, moth, processionary. Nocturnal ones, like cabbage caterpillars, are very common on orchard plants, while moths and moths are pests that often affect the orchard.

guinea pig larva

Strain tenebronis on the other hand it is effective against young beetles, the most important application of this bacterium is the fight against potato dorifora, an insect sadly known to solanaceae growers.

It is also worth mentioning the Bacillus thuringiensis israelensis because it is able to affect mosquito larvae . It is mainly used in water-soluble tablets, useful for recovering stagnant water. This larvicide is perfect if there are rainwater collection buckets near the crops, which could otherwise become tiger mosquito farms.

How to use bacillus thuringiensis

In the presence of nocturnal attacks or pesticides, the bacillus thuringiensis can spread in the plants, the spores must be diluted in an aqueous solution. For better efficiency, the treatment must be done at night, because the larvae come out at night to attack the vegetables. In addition, the spores of this insecticide are not very resistant, in particular heat and light can make the product harmless, hence the advice to carry out treatments at night.

The bacillus is not effective by simple contact: it must be ingested, and it only affects larvae, it is not useful against eggs and adult individuals. This is why it is important to treat it at the right time, to kill the parasitic generation before it can develop. Against adult insects in organic farming, other products are used instead, such as neem oil and pyrethrum, the latter must be careful because it is not selective and although of natural origin it is toxic to many organisms.

Where to find bacillus thuringiensis

Insecticides based on Bacillus thuringiensis are commercially available, usually in the form of water-soluble granules. In these cases, it is enough to dissolve the insecticide in water and use it, but more information on how to use it and its dosage can be found on the packaging of each product.

Unfortunately, chemical insecticides are too often recommended in agricultural centers and garden centres, and it is not always easy to find Bacillus thuringiensis, even if it is a very useful product in the garden. Fortunately today you can buy this excellent remedy online Quickly and safely.

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