Practical tips for spraying

Introduction

In this article, which is the result of years of experience and study, an attempt has been made to examine and explore the most practical and effective points in agricultural foliar spraying (fertilizers and pesticides) to increase the effectiveness of the active ingredient. Six of the most important points are explained in detail, and finally it is concluded that not only high quality fertilizers and pesticides guarantee high effectiveness, but also observing the principles and points mentioned in this article will be very effective, and failure to observe them may cause foliar spraying to be wasted and useless.

In this article, the quality of water used, using the appropriate amount and ensuring the exact volume of the tanker, the diameter of the foliar spray droplets, the time of foliar spraying, appropriate facilities and equipment, and important technical points for preparing the fertilizer and pesticide solution, as well as post-foliar spraying operations, have been examined.

In foliar spraying of various types of fertilizers and pesticides, paying attention to the very important points that follow can significantly increase the effectiveness and efficiency of the desired active ingredient in the spray solution.

We must know that the effect of the method and method of foliar spraying is the same as the quality of the poison or fertilizer we want, in other words, the highest quality and most effective poisons and fertilizers are wasted and useless in a poor quality and incorrect foliar spraying

A few important points in this regard are as follows:

1- Quality of water used

The pH and EC of water are two very important factors in foliar spraying. High salinity and alkalinity of water have a negative effect on the absorption and effectiveness of active ingredients.

Increasing the EC of water from 2000 microms/cm and above slowly has a negative effect on the absorption and effectiveness of foliar spraying, so that above 5000 to 8000 microms/cm, the absorption and effectiveness of the active ingredient is probably reduced by about 30 percent. (Depending on the type of poison or fertilizer)

Unfortunately, it is sometimes seen that foliar spraying is carried out with an EC higher than 15000 microms/cm. In foliar spraying with very salty water, not only is the absorption and effectiveness of the active ingredient reduced, but harmful and disturbing elements of plant physiology such as sodium and chlorine are also absorbed.

Since reducing the EC is not easily possible, it is recommended to use water sources with less salinity that are located around the agricultural lands in question for foliar spraying, as much as possible.

High pH and alkalinity of water are also negative points that reduce the absorption and effectiveness of the active ingredient, this is especially noticeable in fungicides.

Using water with a pH higher than 5.7, especially in fungicides, can sometimes make up to half of the active ingredient ineffective and ineffective after an hour of preparing the desired dose.

Fortunately, there are many pH control solutions in the agricultural market today, which can be used to reduce the pH of the water to the desired level and be safe from its negative effects.

The appropriate pH for foliar spraying is between 5.5 and 6. With amphoteric compounds available in the agricultural market (PH controllers), the pH of the tank environment can be easily and with a small amount brought to the desired level.

In addition, the use of hairs, especially for fertilizers and systemic pesticides, helps greatly in absorption. These compounds reduce the surface tension of water and cause the droplets to spread and adhere well on the leaf surface, increasing absorption.

2- Using the right amount and ensuring the exact volume of the tanker

Many of the tankers used are not standard and their actual volume is different from their nominal volume, this disrupts the appropriate dose and amount and causes the desired result of spraying to not be achieved.

By measuring the dimensions of the tanker and using simple mathematical relationships, the volume of the tanker can be measured with a close approximation to the real one. The desired dose must be prepared taking into account the exact volume of the tanker.

The dose and amount of poison or fertilizer recommended by the relevant experts or the manufacturer should be considered and prepared according to the same instructions. Obviously, any change in the recommended dose and instructions will affect the result of foliar spraying.

3- Foliar spray droplet diameter

One of the most important points in an effective and highly efficient foliar spray is the size of the droplets coming out of the nozzle. It should be noted that the goal of an effective foliar spray is for the droplets to be on the surface of the leaf, not to wash the plant and for water and dissolved substances to fall onto the soil.

The diameter of the droplets is expressed in micrometers. Each micrometer is 1/1000 (one thousandth) of a millimeter. Usually, very small droplets are more effective, but due to their lightness, there is a possibility of being scattered by the air flow and not reaching the main target, the leaf. On the other hand, very large droplets, although they are on the surface of the leaf, are more likely to fall onto the soil.

The classification of droplets according to their diameter is as follows:

Studies show that the optimal droplet size varies for different products

but in general:

Fungicides, contact herbicides, and foliar fertilizers work best with small to medium diameters, and systemic herbicides (soil-based or pre-emergence) and systemic herbicides work best in the medium to large range.

There are two key considerations in choosing droplet size: the coverage and contact area that you want to apply, and the environmental factors that affect foliar application.

Smaller droplets cover more of the leaf surface and create a larger contact area. Using air induction nozzles can make the droplets larger and provide a better and more effective foliar application.

On the other hand, wind entrainment and evaporation of fine or very fine droplets are much greater than medium-sized droplets, and also in tall trees or trees with dense crowns, large droplets have better and greater penetration.

Choosing the size of the droplets is a balance, small droplets give us more coverage and contact surface, but the risk of evaporation and wind entrainment also increases. In contrast, larger droplets have good penetration and settlement and are a good option for tall trees, but they may give us less contact surface and coverage.

Sometimes, the labels of pesticides and fertilizers give appropriate recommendations in this regard that can be used.

Using Air Induction nozzles (Air Induction) when we want to have finer droplets and wide-angle nozzles when larger droplets are needed increases efficiency and reduces environmental pollution.

4- Spraying time

The best time for foliar spraying is early morning or evening, meaning the time between dawn and sunrise.

At the above times, lower temperatures and higher relative humidity cause evaporation to decrease and, as a result, absorption to increase, and also eliminate the risk of leaf burn and stress and tension caused by spraying in the heat of the afternoon.

The best temperature for foliar spraying is between 15 and 25 degrees Celsius, and the wind speed should be less than 5 meters per second.

Do not spray during or when there is a chance of rain. Rainfall several hours after spraying systemic fertilizers and pesticides does not have much effect on absorption, but rainfall even a few days after the solution has been applied. Spraying contact and digestive poisons reduces the effect of the poison.
Watering the plant before foliar spraying has a very positive effect on the absorption and transfer of active ingredients and also reduces the risk of leaf burn, so try to spray when the plant is well-hydrated and fresh.

5- Suitable facilities and equipment

A- Agitator

In order to have a uniform and uniform solution during the foliar spraying period and to prevent sedimentation and the solution from becoming two-phase, it is necessary to have a spray tank equipped with With a stirrer. If small tanks are used for spraying and do not have a stirrer, it is recommended to place the spray lance inside the tank every few minutes with maximum pumping.

Continuous stirring is essential, especially for suspension and emulsion mixtures. For example, if Volk oil is used, if a stirrer is not used and the oil and water do not mix, the spraying solution will be very poor and uneven, and the possibility of leaf burn will increase.

Remember that the water returning from the pump to the tank or the shaking of the tanker never performs the stirring action and does not create a uniform solution.

It is better to first dissolve the desired fertilizer or pesticide well in a smaller volume and then pour it into the main tank.

B-Types Lance

There are several lances that can be used depending on the application. Obviously, the proper and timely use of each of them increases efficiency.

Straight lance (Telescopic Lance) Curved Lance Gun Lance Turbo Jet Lance There are a number of types of lances, each of which provides the best solution in specific cases. For example, a curved lance with an angle of 40 or 60 degrees provides spraying on the underside of leaves and for pests such as whitefly or mites without the operator bending over.

When choosing a lance, the following points should be considered:

– Type of crop and plant height

– Sprayer pump capacity and working pressure appropriate to it

– Rustproof and lightweight lance
– Use of filters at the inlet to the pump and lance

ج- انواع نازل ها

D- Clothing, Mask and Filter

Maintaining the safety and health of human resources is one of the most essential and important principles that must be considered. Contact of poisons and fertilizers with the skin, their entry into the lungs, eyes and mouth may have irreparable negative effects on the operator, therefore

Appropriate and safe clothing is one of the primary priorities in any type of foliar spraying.

The specifications of the appropriate coverall are as follows:

1- Coverall or Overall

The coverall should be made of laminated polyethylene, impervious to droplets and mist, with elastic cuffs and legs or with adhesive capability.

2- Long, chemical-resistant gloves

Never use cloth or leather gloves.

3- Rubber boots up to the knees

4- Brim hat or hood

Another important issue in spraying is the use of a suitable mask and filter.

It is important to note that paper or cloth masks are not at all suitable for spraying chemical compounds.

It is essential that the operator uses a half-face or full-face mask with a replaceable filter. P3 filters are the most suitable filter, especially when using powdered pesticides or heavy fogging.
Using glasses or shields is also necessary and essential, especially when mixing materials and washing the machine.

6- Important technical tips in preparing fertilizer and pesticide solutions and post-spraying operations

A- Be sure to pay attention to the recommendations on the label as well as the opinions of relevant experts. The dosage and amount of use should be prepared with great care. Safety tips should be considered with great care and emphasis.

B- One of the important points, especially in spraying, is paying attention to the withdrawal period. The withdrawal period is the period of time after spraying that the amount of active ingredient in the plant decreases to such an extent that it is not harmful to humans. Paying attention to this point means that the remaining poison in agricultural products is becoming more important day by day.

C- Mixing different materials, including mixing pesticides and fertilizers, is desirable for the farmer, because it is economically efficient. But mixing is not advisable and mixing should be avoided as much as possible. If you insist on mixing, be sure to consult experienced experts. Sometimes mixing different substances reduces their effect or even has negative effects on the plant.

D- The frequency and repetition of foliar spraying should be done according to the needs of the plant and the advice of nutrition experts or plant doctors.

E- Immediately after the completion of the foliar spraying operation, the sprayer tank, pipes and nozzles should be washed with clean water. If oily or sticky pesticides are used, a washing solution (water + a little detergent) should be used. Mask filters should be replaced every so often and clothes should also be washed.

F- Excess solutions and equipment washing water should not be discharged into waterways and drainage channels, but should be poured according to the instructions on the cans in lands away from agriculture and the living environment that do not harm humans and plants. Empty containers of pesticides and fertilizers should be buried in a sanitary manner or delivered to collection centers.

G – After completing the spraying operation, the operator must take a shower, although care must be taken during spraying to ensure that the spraying mixture does not come into contact with the skin and eyes.

سه برگی

پنج برگی

Today, foliar application of various fertilizers and absorption through leaves is a common and effective thing in agriculture. Paying attention to the key points mentioned above will definitely increase the efficiency and effectiveness of foliar application fertilizers. We have seen this at Nikookar Trading Group (importer of the Zenith brand). We use the fertilizers Amino Sun and Aljisan Zenith Germany Company, mixed and applied in several times at the beginning of the growing season, visibly improves vegetative growth and successful grain setting. We have observed this in Kerman pistachio orchards and by observing the principles of correct foliar spraying and by comparing it with the control.

Very good leaf growth, its green color, and also the increase in five leaves compared to three leaves clearly show the effectiveness of this foliar spraying in pistachio orchards.

I consider it necessary to mention this point again that not only the high quality of fertilizers and pesticides guarantees high effectiveness, but also observing the principles and points mentioned in this article will be very effective.

Hoping for bright days in the future of Iranian agriculture

Author: Seyed Farid Sayah

Senior Expert in Fertility and Soil Chemistry

Technical Director of Nikokar Trading Company, importer of Zenith Germany products