This topic is unforgivably little discussed in the press, although absolutely everyone faces it when using pesticides. The director of marketing and sales of August, Mikhail Evgenievich Danilov, took the matter of education into his own hands and wrote a detailed review of the factors affecting the effectiveness of pesticides. In this issue, we begin to introduce you to it.

Unfortunately, sometimes we have to deal with complaints about the effectiveness of our products. And let an employee of any of the other most respected multinational pesticide and/or agrochemical companies whose big name has saved him from claims throw a stone at me. Complaints that are often completely unrelated to the quality of the particular product used.

Of course, it would be more pleasant for us not to enter into a discussion of this slippery topic, but simply to build a protective armor in the description of drugs with beautiful phrases, as is customary for some companies that are skilled in fending off multimillion-dollar consumer lawsuits (to be honest, they are often quite poorly substantiated). Something like that, following the example of one of the major pesticide manufacturers. A quote from its official website:

“These recommendations are based on our current experience and comply with the regulations approved by the registration authorities. They do not exempt the user from his own assessment and consideration of a large number of factors that determine the use of our product Producers of agricultural products are responsible for strict compliance with the requirements of technology and regulations For our part, we exclude any responsibility for the possible consequences of such use of the drug.

Various factors due to local and regional characteristics can affect the efficacy of the drug. First of all, these are weather and soil-climatic conditions, varietal specifics, crop rotation, treatment period, consumption rates, tank mixtures with other preparations and fertilizers (not specified in our recommendations), the presence of resistant organisms (pathogens, plants (weeds), insects and other target organisms), inappropriate and/or unregulated equipment for use, etc. In the case of particularly unfavorable conditions not taken into account by users, a change in the efficacy of the product or even damage to cultivated plants cannot be ruled out, for the consequences of which we and our trading partners cannot be held responsible.”

In general, everything written is written correctly. It should be noted that the overwhelming majority of claims that August has to consider are not related to deviations in the quality of our products. It is not for nothing that the company is proud of its modern plants equipped with the latest chemical science. We opened the third plant in the summer of 2019 and are pleased to invite our partners there. The opening of the fourth one (already for the production of active ingredients) was planned in March 2020 in the province of Hubei, which we all know infamous about. For obvious reasons, the official opening had to be postponed.

ASSESSMENT OF CIRCUMSTANCES

And the complaints about the work of chemical protective equipment are related precisely to the fact that the condition highlighted in the above quote – a qualitative “assessment and consideration of a large number of factors that determine the use of our drug”, from which “the user is not exempted”, was lame in this user (like the spelling of Winnie-the-Pooh, which, “in general, is good, but lame”).

In the same way, it is sometimes not possible to accurately indicate all the factors in advertising materials. It is also not always possible to place accents on studies and presentations. After all, a specialist, as Kozma Prutkov used to say, “is like a flux: its fullness is one-sided.” The specialist’s eye is “blurred”, attention is not always focused on things that seem obvious and understandable to him. And for a layman, these “obvious” moments can be like absolute terra incognita.

For example, we wrote that the drug should be used in the temperature range of 15 – 25 ° C. We released ourselves formally from responsibility if our product was used in thirty-degree heat. And indeed, it is not good to carry out treatments in heat or cold. But sometimes it’s not good, but it’s necessary. And it would be necessary to explain to the client in which cases it is not good and not necessary, and in which cases it is not good, but if it is really necessary, then it is still possible.

15 FACTORS

Let’s abstract from what is stated in the flyers and registration documents and go through the external factors that can nullify the effectiveness of the highest quality product. Let’s trace the path of our drug from the plant to the target object. And let’s try to understand what factors can “lead him astray”.

These factors include:

1. Conditions of carriage and storage.
2. Quality of the water used for the preparation of the working solution (pH, turbidity, composition of dissolved salts, temperature).
3. Weather conditions both at the time of application and before and after application (air temperature and humidity, wind, temperature inversion, precipitation before and after spraying).
4. Sprayers used, types of spray nozzles and sprayer operating modes (working solution consumption rate, droplet size, number of drops per unit area of the treated plant and the effect of this parameter on systemic/contact pesticides).
5. Characteristics of the soil (presence or absence of plant residues and clods on it, soil structure and moisture, properties of the soil absorbing complex).
6. Agrotechnical methods of tillage and crops used during the growing season.
7. The development phase of weeds and their condition.
8. The phase of crop development, its condition and varietal features.
9. Stage of disease development.
10. Stage of development of the pest.
11. The presence of resistant weed biotypes, pests and diseases, alternating pesticides with different mechanisms of action to reduce the risk of the emergence of resistant species.
12. Tank mixtures of pesticides, agrochemicals (physicochemical and biological compatibility) used.
13. Pesticide aftereffects, crop rotation restrictions.
14. Taking into account the peculiarities of the registration of active ingredients (hereinafter referred to as the active ingredient) in different countries and the norms of the maximum permissible levels of residual active ingredient content in products.
15. And something else that I forgot to mention – so write to us, we will consider it in subsequent materials.

FORMULATION & PACKAGING

But we will start not with external factors, but with internal ones – with formulation and packaging. In order to understand the quality of the formulation, it is worth visiting any of the August factories, here the stories are meaningless, it is worth seeing at least once. In addition, it should be borne in mind that during the production of each batch, arbitration and representative samples are taken, which are stored at the plant and by which it is always possible to check the compliance of the drug with the technical specifications.

As for packaging, since the beginning of 2020, the August company has introduced the marking of each individual storage unit (canister, vial, bag) with a unique data code at all plants. We are talking about professional products. In preparations for summer residents (LPH), we use a different labeling. And even now, with the help of the August Checker mobile application, you can check the authenticity of our products (we talked about this in detail in No. 1/2020 of the newspaper “Pole Augusta”). The August AgroMarker and August AgroWarehouse programs will allow us to track the issuance of products and the return of empty canisters in the warehouses of our consumers.

Similar or similar markings are also found on the products of a number of other manufacturers. August has come up with an initiative to create a single labeling standard and software for the pesticide production and circulation industry. We hope that this will be the case.

So let’s assume that along the entire chain of movement of our products, we are talking about a high-quality and original product, and not about counterfeit.

CONDITIONS OF CARRIAGE AND STORAGE

Problems may arise on the way from the Augusta warehouse to the consumer’s warehouse and during storage there. All pesticides have specific storage temperatures. Some (for example, Tornado) are perfectly frozen in the vast expanses of our homeland, and then defrosted without losing their effectiveness. Therefore, they can be transported and stored within relatively wide temperature ranges. And there are drugs with which this trick is impossible: they should be stored only in conditions of positive temperatures.

Be sure to pay attention to this. All manufacturers are aware of such features and give recommendations on the temperature regime of storage. In addition, this information is always indicated on the label. If the conditions of the season are such that you have some leftovers of warm storage products, be sure to move them to a heated warehouse for the winter. If, due to negligence or other circumstances, the drug was stored in unsuitable conditions, check it before use with the help of the same manufacturer. It is able not only to assess the content of active ingredient, but can also determine the quality of the formulation by other indicators that affect the effectiveness of the pesticide.

Water Factor

Let’s remember a wonderful line from a song based on the lyrics by Leonid Derbenev – “It is not beer that destroys people, it is water that destroys people.” Of course, it is unlikely that anyone will come up with the idea of making a working solution based on beer, but preparing it on the basis of water, without assessing its quality, is a more than common situation.

And if we say that in order to assess the effectiveness of pesticides in accordance with the methodology of field experiment, it is necessary to set up a one-factor experiment, we often forget that water quality is also a factor that can sometimes turn out to be limiting for a particular working solution.

WHAT IS WATER

We are very often asked questions regarding the preparation of tank mixtures. They ask what preparations are combined in terms of biology, physicochemical indicators, etc., but at the same time they forget what water itself is. It would seem that the question is simple: at a temperature of 0 to 100 °C, it is a transparent liquid, each molecule of which consists of two hydrogen atoms and one oxygen atom, that is, H₂A. But the water that we use in life, whether pure drinking or technical, is no longer water from the point of view of physical chemistry. At best, it is a ready-made tank solution of various salts and gases, and at worst, it is a solution with a composition of various suspensions and emulsions. Because even in drinking water, according to the norms of the relevant Sanitary Rules and Regulations, the total mineralization can reach up to 1 g/l, which means that 100 liters of such water can contain up to 100 g of various salts. What can we say about non-drinkable water!

So to this “tank solution”, 100 liters of which contains from several tens to several hundred grams of various unaccounted compounds, we sometimes add grams of active ingredients in the form of our pesticide, lovingly formulated under conditions of medical purity. And then we can’t understand what kind of drug it is – sometimes it works, sometimes it doesn’t. It seems that there is only one party, and they did not steal it on the way, and stored it correctly, but on this field the effect of it is zero, but on another one a dozen kilometers away everything is fine. Although it was applied simultaneously on the same crops and weeds, under the same weather conditions, sprayers, sprayers and regimes. And the secret is simple – “it’s not beer that kills people, it’s water that kills people” (although beer also kills, of course, but that’s beyond the scope of this article). The drug did not work because the content of specific impurities in our real water had a catastrophic effect on its effectiveness.

What properties of water should you pay attention to?

DISSOLVED SALTS

First of all, we are talking about hardness salts – calcium and magnesium (hard water and ways to correct it were the subject of a detailed article in No. 7/2019 of the newspaper “Pole Augusta”).

The chemical composition is more or less constant for artesian water, so if you have determined it in a specialized laboratory, you can be guided by this analysis for many years. And on the basis of it, make a decision: whether to fix the water for you or not.

If you use water from surface sources or shallow wells, an analysis made even a few days ago can only be of historical value. And have nothing to do with the current composition of your water.

To quickly determine the hardness of water, you can use such an indirect indicator as its electrical conductivity, which, in turn, can be easily measured using a conductivity meter. This portable device costs $50 to $100. per piece, depending on the strength and “coolness” of the model. Every self-respecting agronomist or consultant should have such a device. There are conductivity meters that are cheaper, but they tend to fall apart quickly. If the electrical conductivity of your water does not exceed 500 microsiemens/cm, it can be considered conditionally suitable for spraying in terms of hardness.

If this value is higher (or you want to be on the safe side and slightly increase the effectiveness of the products), then the water must be corrected for the preparation of pesticide solutions with active ingredient based on water-soluble salts of organic acids or just such acids. Here is a list of active ingredients and some trade names of Augusta drugs (this also applies to the products of its competitors).

• 2,4-D (Biolan Super)
• Aminopyralide
• Acifluorfen
• Bentazon (Corsair, Corsair Super)
• Glyphosate (Tornado, Tornado 500, Tornado 540)
• Glufosinate
• Dicamba (Deimos, Biolan Super, Doubloon Super)
• Imazamox, Imazapyr, Imazetapir (Paradox, Corsair Super, Grader, Fabian)
• Quinclorac
• Quinmerak (Tranche Super)
• Cletodym (Graminion, Quickstep)
• Clopiralid (Galion, Hacker)
• MCPA (Herbitox, Herbitox-L, Gorgon)
• Picloram (Galion, Gorgon, Ballerina Forte)
• Setoxidim
• Tepraloxidim
• Tralcoxidim

To correct the water, various conditioners based on orthophosphoric, oxalic, citric acids are used – they are liquid, convenient and include signal dyes and buffer agents in their composition. Avgust also has such an air conditioner – this is Soylent. Ammonium sulfate can also be used, but it is much more difficult to work with, especially if there is no solution unit.

It should be borne in mind that Soylent is strictly contraindicated for the fungicide Kumir (copper sulfate tribasic, 345 g/l). This is also true for most air conditioners for copper salt fungicides.

Note that in addition to dissolved hardness salts, sodium salts can be present in water in significant quantities. In our practice, we have come across artesian waters with such a content of chlorides, sulfates and sodium bicarbonates that it was easier to classify them as mineral. Although the calcium and magnesium content was not as high, salt water can have an electrical conductivity of several thousand microsiemens/cm. Since salt (and even not at all hard) water is often contraindicated for preparative forms in the form of concentrates, emulsions and suspensions. And water-soluble bags (a number of drugs have such packaging) become extremely insoluble in such water. Therefore, you should be careful with salt water, because even without binding active ingredient, it can have an extremely negative effect on the durability and effectiveness of emulsions and suspensions.

ACIDITY

Acidity, or pH, can be quickly determined either with indicator paper (with very low accuracy) or with a portable pH meter, which, unlike a portable conductivity meter, requires much more care. Using this device in camping conditions is not very convenient.

For most pesticides, in terms of both their stability in the working solution and their effectiveness, it is a good idea to have a slightly acidic working solution. This is due, on the one hand, to the instability of the majority of active ingredient to alkaline hydrolysis and, on the other hand, to the fact that acidic environments can contribute to better penetration of active ingredient through the cuticle of plants. Soylent and similar conditioners bind hardness salts and acidify the working solution at the same time, so it can be used to soften water and acidify it at the same time. Moreover, natural water, with rare exceptions (swamp waters, for example), has an alkaline reaction (primarily due to sodium, calcium and magnesium bicarbonates dissolved in it). And you don’t need a pH meter that needs careful care.

In principle, if the electrical conductivity of your water is low (the same 500 μS/cm), and the pH is not much away from the neutral value (not much higher than 7), then for most drugs acidification of water is not an urgent need, although, of course, it does not hurt. The exceptions here are fungicides based on copper salts and, to some extent, preparations based on sulfonylureas, which are subject to acidic rather than alkaline hydrolysis, and therefore are less stable in acidic solutions than in alkaline ones.

Nevertheless, there are a number of active ingredients for which acidification of the working solution to the pH level of 5-6 is highly desirable. Sometimes, due to weather conditions, it is necessary to leave the working solution in the sprayer or in the solution unit. Some manufacturers (insuring against possible claims) write in the recommendations that the use of the working solution should take place immediately after its preparation. But, as Goethe used to say, “Theory is dry, my friend, but the tree of life grows luxuriantly green.” Therefore, not for theorists, but for practitioners, taking into account the pomp of real life, here is a list of active ingredients for whom water with an alkaline reaction (pH>7) is extremely undesirable. Especially in the situation described above, when there are problems with the immediate application of the working solution after preparation. Tank mixtures with alkaline agents (for example, such as sodium or potassium humates, the pH of which can reach values of 9 – 10) are also contraindicated for these active ingredients.

Here is a list of active ingredients used in Augusta preparations subject to alkaline hydrolysis, for which a working solution based on water with an alkaline pH requires acidification (use the same Soylent):

acidification is mandatory: desmedipham (Biceps 22, Biceps Garant), fenmedifam (Biceps 22, Biceps Garant), as well as FOPs – phenoxaprop-P-ethyl (Eraser 100, Eraser Top, Eraser-Extra), clodinafop-propargyl (Eraser Top), haloxifop-P-methyl (Quickstep), quizalofop-P-ethyl (Miura) and malathion (Alioth);

acidification is desirable: dimethoate (Sirocco); pyrethroids – alpha-cypermethrin (Boreas Neo), lambda-cyhalothrin (Breik, Borey), cypermethrin (Shar Pei), esfenvalerate (Senpai), as well as chlorpyrifos (Taira) and cymoxanil (Ordan).

It should be borne in mind that the preparative form is somewhat wider than the active ingredient, and therefore there may be some special recommendations for specific drugs.

A question that often arises is: what to do with tank mixtures of betanal drugs and triflusulfuron-methyl? In this case, we choose the side of the active ingredient that is most susceptible to decomposition. Sulfonylureas will tolerate the acidic reaction much more easily than desmedifs and phenmedifs will tolerate alkaline hydrolysis. We acidify it and do not suffer from doubts.

TURBIDITY

Water can be turbid due to various fine suspensions, organic and inorganic. Organic and clay impurities have a very negative effect on active ingredients, which have a high value of the organic carbon/water partition coefficient (English abbreviation KOC). The higher this coefficient, the more the substance is subject to absorption. In muddy waters, such a d.v. becomes passive instead of active.

When the CBS value is measured in tens of thousands (glyphosate) or millions (diquat) units, it is a signal to think hard about the turbidity of your water. However, measuring it with instruments and determining its nature is a task for too inquisitive minds, requiring complex instrumentation. That is why the Americans invented a method that cost them only 25 cents, which at today’s exchange rate is only about 20 rubles. I have improved this method, and in the Russian expanses it will cost you exactly 10 times cheaper – only 2 rubles. You take a two-ruble coin, throw it into a full bucket of water (10-12 liters), and if you see it at the bottom, then such water is considered conditionally suitable in terms of turbidity. And if you don’t even see a five-ruble coin (although this happens quite rarely), your money cried. Look for another source of water to prepare the working solution.

Diquat and glyphosate are extremely sensitive to murky water, oxyfluorfen and pendimethalin also do not like it. As for the other types of ingredient, I recommend that you take a look at the rupest.ru website and look at the “Environmental Behavior” table for the specific value of the CBS for the ingredient you are interested in. If it says “does not move” next to the value, it means that cloudy water is categorically contraindicated for your drug.

TEMPERATURE

Most often, problems arise with very cold water – not all formulations can tolerate it. This leads to difficulties in the preparation of working solutions in mortar units (especially where urea or saltpeter is added to this water, after which the temperature drops below zero), in sprayers and disinfectants. This applies not only to the d.v., but also to other components of the formulation. Pay attention to this! Take specific preparations and make a test solution with water from the refrigerator.

Material of the newspaper “Pole Augusta” No 5, 202