WUXAL Buffering agents

06.01.2022 – The performance of your spray mix with foliar fertilizers and crop protection products is strongly affected by the pH value of the mix. In this episode of WUXAL Spotlight, Johannes Krümpel will show you how you can improve your spray quality using WUXAL with its buffering agents.

Watch the video on our YouTube channel.

Buffering agents as part of the WUXAL Additives

WUXAL Products offer a lot of high-performance additives to improve nutrient uptake and the condition of your spray mix. These additives like chelating agents, humectants or stickers are combined in our products through our unique formulation technology.

We will explain each additive in detail in separate postings. In this post, Johannes gives you detailed information about the additive „Buffering agents“.

Buffering agents and the pH value

Buffering agents are closely connected to the pH value of a substance. The pH value can be described on a scale from 0 to 14. A neutral solution has a pH of 7. Values below 7 are considered acidic. Alkaline substances, on the other hand, have a higher pH than 7. The further the number is from 7, the stronger the effect.

Buffering agents keep the pH value of a solution stable, even when an acidic product or alkaline product is added. Buffers should therefore always be the first product that is added into the spray mix.

When buffering agents, such as those integrated in WUXAL, are added to an acidic or alkaline solution, the pH adjusts to an optimal buffer range around 7 or slightly below and keeps the pH in this range.

The effects of the pH value on the spray mix

The pH value of a spray mix is of particular importance for foliar nutrition and crop protection.

Effects on nutrient uptake

An optimal pH of the spray solution results in a maximum uptake of nutrients via the plant surface. There are differences in the optimal pH for an optimal foliar uptake for each crop and for each nutrient, but a neutral to slightly acidic pH provides the best conditions for rapid uptake of all nutrients.

Effects on the stability of active ingredients

The pH value of the application solution has an even greater effect on the efficiency of the crop protection product in the mix. This is because the active ingredients in crop protection products are sensitive to unfavorable pH values. If the pH value is too high or too low, the active ingredients lose their effect. For most crop protection products high pH values in the mix are very critical.

For example, a herbicide for sugar beet that contains Desmedipham as well as other active ingredients has a half-life at pH 9 of only 10 minutes. The half-life determines how long the active ingredients remain stable and active. With a half-live of 10 minutes, 50% of the complete active ingredients in the spray mix are not usable anymore after only 10 minutes. And after 20 minutes even 75% of the crop protection product has been deactivated so far.

Stability without buffering

If after 20 minutes 75% of the crop protection’s effect has already been lost and you do not mix the spray directly in the field, you have lost most of the effect before you have even started spraying. So, you pay a high price to apply inactive products.

A slightly acidic to neutral pH on the other hand extends the half-life and thus maximizes crop protection stability. The WUXAL buffering agents keep the pH in this range.

Remember that we can adjust the pH to a level around or just below 7 by adding WUXAL. This significantly extends the half-life to 14 h 30 min. After a time of 10 minutes, we now do not notice any loss in crop protection efficiency, and neither after 20 minutes.

Stability with WUXAL

On the other side, competitor products based on carbonates or oxides often cause very high pH values and thus unfavorable conditions.

The high loss of stability of the crop protection product with Desmedipham is not unique to this product. In fact, most crop protection products are unstable at high pH values. So are fungicides with Thiophanate-methyl or Captan and insecticides with Indoxacarb.

Efficiency experiment in garden cress

In a trial, garden cress was treated with the same crop protection product containing Desmedipham that we have talked about before. This product is used in this trial to control the garden cress that represents unfavorable plants in the sugar beet field. So, the aim is to see as little healthy plants as possible.

The trial comprised two variants: The herbicide and water, adjusted to pH 9; and the second with the herbicide, water and WUXAL P45 that buffered the pH to 6.7. This means we expect a much higher efficiency of the mix with WUXAL, as the half-life is much longer than at pH 9.

In both cases, we waited 2 hours after mixing and then applied the mixture. This time slot of 2 hours should reflect the time between mixing the spray, for example on the farm, and application in the field.

You can see in the pictures that the efficiency of the herbicide against the cress was much better on the right side. The combination with WUXAL P45 has a clear visible effect due to the pH buffering towards 6.7.

Practical demonstration

In the video that you can watch on our YouTube channel, you will have an additional practical demonstration of the buffering effect in WUXAL products. Watch the full video there or directly skip to the part you want to see via the time stamps in the video description.

Watch the practical demonstration in the video on YouTube.

Conclusions

Using WUXAL products gives an indirect money cashback due to the high nutritious value and reliable additive effects. That’s why WUXAL products are also equipped with buffering agents.