02 Dec 2024

What is K-Obiol and how does it work?

K-Obiol® is a synergised stored grain protectant that can be used on cereal grains, malting barley and sorghum but cannot be used on oil seeds and pulses. K-Obiol is applied as a liquid spray diluted in water and applied into the auger as the grain is fed into the storage. Importantly, as the name suggests, as a protectant insecticide, it ‘protects’ grain so must be applied to un-infested grain.

K-Obiol contains the active ingredient, deltamethrin, and is combined with a synergist, piperonyl butoxide to increase its effectiveness.

Insecticide Resistance in stored grain?

The ongoing effectiveness of all stored grain insecticides, whether they be grain protectants (like K-Obiol containing deltamethrin and products containing spinosad) or fumigants must be managed as effectively as possible to minimise the onset and development of resistance to various stored grain insects.

As an industry, it is critical that applicators heed the advice provided by the various industry experts and advisors for this to be as effective as possible. Insecticide resistance to our currently available control options is developing and for some species such as Lesser Grain Borer and Rice Weevil, we as an industry, are already experiencing the effectiveness of protectants and fumigants being impacted across widespread regions.

When using K-Obiol, the addition of an organophosphate registered for use on stored grains such as fenitrothion or chlorpyrifos-methyl is required. The choice of which will depend on the intended end-use market and what grain is being treated.

Rotation?

It is a good practice, where possible to rotate on a seasonal basis between K-Obiol as a base protectant to products containing the base protectant, spinosad to help minimise the development of insecticide resistance. Like K-Obiol, spinosad also requires the addition of organophosphate and in some cases s-methoprene (refer to the label for further instructions).

Protectants vs Fumigants

When protectants are used in accordance with the label instructions, they can protect un-infested grain in storage for up to nine months (refer to label). Importantly, because protectants are applied as grain is moved into storage, they can be used with sealed OR unsealed silos.

Fumigants, which are applied to grain once IN storage, must be applied to gas tight sealed silos to be effective. Much of the inconsistency with fumigation and rapid onset of resistance that has already developed is due to applicators attempting to fumigate grain in storages that are not adequately sealed. When fumigants are used in sealed storages, they disperse evenly and thoroughly and unlike protectants can control existing insect infestations very efficiently. In contrast fumigant used in unsealed gas tight storage can result in grain not being treated evenly or for long enough leaving portions of the grain untreated and infested with insects. And once the fumigation has finished, and without any residual protection, like protectants, insects that have survived can continue to reproduce and infest more of the grain.

Both methods have their pros and cons with the decision often coming down to whether the storage is sealed (either fumigant OR protectant options) or not (protectant option only).

K-Obiol – an industry leader

The effectiveness of the current K-Obiol EC Combi formulation, has been successfully used as a stored grain protectant by the Australian grains industry for almost 11 years. K-Obiol was the first grain protectant used on-farm with a stewardship program to provide users with all the information they needed to successfully use K-Obiol on their stored grain.

Between October 1^st & December 31^st, purchase a bottle of K-Obiol® EC Combi from your local Nutrien store, for your chance to win a Complete Grain Spray System for the treatment of your stored grain. Follow this link to find out more!

For more information on K-Obiol EC Combi insecticide visit the Envu website. Always read the label before use.

*DISCLAIMER:

The information provided in this article is intended as a guide only. Information contained in this article has been provided by the manufacturer/ You should not rely on the information in this article, and it should not be considered advice. You should seek professional advice regarding relevant factors specific to your situation. This article does not take into account variable conditions that may impact performance. Always read and follow label directions before using any product in this article. To the maximum extent permitted by law, Nutrien Ag Solutions Limited and its related associated entities will not be liable for any loss or damage suffered by any person arising out of any reliance on any information contained in this article.