Do not know how to convert the dosage instructions printed on the pesticide packaging?

As we all know, pesticides are no more common things for us farmers.
After all, all the crops we grow are inseparable from the use of pesticides for their healthy growth and development
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But after all, pesticides are different from other products, and their use requirements are relatively strict.
Therefore, this requires us to grasp the correct dilution factor when spraying and using crops
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In fact, with regard to pesticide dosage instructions, the manufacturer printed the corresponding usage method on each product package
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But everyone knows that at present, our farmers in China are mostly those from the 1950s to the 1970s, and people in that period are because the living conditions of their families were generally poor at that time, which led to the fact that people in that era were basically poor.
I haven't read any books on the website, and many people don't even know a few words, let alone understand the dosage instructions on the pesticide labels
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In addition, because pesticide manufacturers are in line with international units, the usage instructions on some labels generally use xx g/mu, xx g/ha; or xx mg/kg, instead of the familiar dilution.
The multiple is xx times
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In the face of these usage instructions marked in international units, even many literate farmers such as the post-80s, post-90s and other new-type farmers and high-quality farmers are at a loss and don’t know how to convert them.
Even the younger generation of cultural people don't understand them, let alone look forward to the older generation of peasant friends born in the 50s and 60s who generally have no cultural education
.
It was not a few days ago.
Lao Hei also received a private message from a fan friend.
He also didn't understand the conversion of xx grams/mu of the usage labeling method.
He wanted me to help explain the popular science
.
So, friends who followed me before know that Lao Hei also specially produced a technical video a few days ago to explain the pesticide dosage in a more specific way, but after the video was sent out, he received feedback from many fans and friends.
They said that the speed of the video is relatively fast, and the conversion formula is not written on the blackboard, they need to take a private screenshot, and they don’t know the conversion formula, so it is difficult to understand and it is difficult to absorb and digest. .
Therefore, Lao Hei decided to write a special graphic today to supplement the topic last time, so that everyone can absorb and digest this conversion formula
.
Common labeling methods for pesticide dosages Generally, there are three common labeling methods for pesticide dosages in our daily life, namely xx g/mu, xx g/ha; xx mg/kg; and the familiar dilution factor is xx times
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So for these three labeling methods, I believe that most people can accurately convert the corresponding water volume for the last labeling method, but they are not very clear about the first two ways of labeling in international units
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In fact, such labeling methods as xx g/mu, xx g/ha; xx mg/kg, etc.
, are the ppm we often say, and it represents the concentration of the medicine in parts per million
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So next, Lao Hei will tell you about the conversion methods of the labeling methods of the three pesticide dosages
.
1.
The labeling method is to directly state xx times.
For some pesticide packaging instructions, the general conversion method is relatively simple.
This is also a conversion method that many fruit farmers are good at
.
Therefore, for this conversion method, Lao Hei did not explain it in detail in the last video, but for some newcomers who are just getting started can understand it, so today Lao Hei decided to also use this conversion formula here.
And write it out
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Then take this 100g/L pyriproxyfen EC formulation as an example, the net content is 100ml, and the dosage instructions on the package indicate that the dosage of the preparation for preventing and controlling psyllids and scale insects on citrus trees is 1000- 1500 times liquid, it means that this 100ml bottle of pyriproxyfen can be diluted with water in total by 200-300 kg of water
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So how is this converted? Generally speaking, in our production, the default weight is 1ml=1g.
Of course, the density of some pesticides is different.
For example, fluazinam has a higher density and specific gravity, so 1ml of fluazinam solution is more than 1g.
In the same way, some pesticides such as mineral oil have relatively low density and specific gravity, so 1ml of mineral oil solution will not weigh 1g. .
However, in actual operation, for the convenience of calculation, we generally ignore the difference in the density of different pesticide formulations and calculate it according to the formula of 1ml=1g
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As we all know, 1 kg=500g=500ml, so 100ml=0.
2 kg, then 0.
2 kg is multiplied by the dilution multiples of 1000 and 1500 to obtain the dilution dosage of 200 and 300 kg of water respectively
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So if the dilution factor is known to be 1000-1500, you need to calculate how many milliliters of liquid medicine need to be poured into a sprayer water (usually 30 kg as an example), would you calculate it? In fact, the same is true.
Just now the net content and dilution factor of the pesticide formulation are known, and we need to calculate the corresponding amount of water added, that is, the net content × dilution factor = the amount of water added
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So now it is the other way around.
Knowing the amount of water added and the dilution factor, we need to calculate the corresponding net pesticide content
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That is, the amount of water ÷ dilution factor = net content, so we put the corresponding number into this formula to calculate
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Here you need to pay attention to first convert 30 kg of water into g or ml, that is, 30×500=15000ml, and then use 15000÷1000 or 1500 to get the two values ​​of 15ml and 10ml respectively
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2.
In fact, the amount of pesticides marked with xx g/mu and xx g/ha refers to the amount of pesticide used per unit area
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When we calculate similar formulas, we don’t need to be disturbed by mu or hectares, because the conversion method is the same regardless of whether its unit area is in mu or hectares
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As everyone knows, 1 hectare = 15 acres, and internationally, it is generally stipulated that the water consumption of 1 hectare is 1000kg, which is 1000000g.
Similarly, the water consumption of 1 acre is equal to 1/15 of the water consumption of 1 hectare, which is 66667 grams. .
And this conversion formula marked by the amount of medicine used per unit area is: 1000000÷the dosage of the preparation per hectare = the dilution factor (when the marking method is xx g/ha or xx ml/ha) 66667÷the dosage of the preparation per acre = dilution Multiplier (when the labeling method is xx g/mu or xx ml/mu) Then take this 100 g/l pyriproxyfen EC preparation as an example, the dosage of the preparation on the tomato whitefly marked on the label is 47.
5- 60 ml/mu
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Then, according to the above conversion formula, the two values ​​of 47.
5 and 60 are substituted, and finally two dilution factors of 1403 and 1111 can be calculated
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That is to say, the dilution ratio of this 100 g/L pyriproxyfen EC preparation on the control of whitefly on tomato is 1111-1403 times
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Finally, after calculating the corresponding dilution factor, the corresponding water exchange amount can be calculated according to the first conversion method
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It should be noted here that if the dosage stated on the label is the dosage of the active ingredient, you need to calculate the dilution factor and multiply it by the total active ingredient content of the pesticide
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3.
The same way of labeling is xx mg/kg, this labeling method is also expressed in ppm
.
We all know that 1 kilogram = 1000 grams = 1,000,000 mg.
Here we take the 80% mancozeb wettable powder produced by a certain manufacturer in the following figure as an example.
The label on the label indicates that the amount of citrus scab is 1333-2000 mg/kg , The corresponding dilution factor is 400-600 times
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So how is the dilution factor of 400-600 times converted here? The conversion formula is: 1000000÷effective ingredient dosage×total effective ingredient content=dilution multiple that is 1000000÷1333×80%=600.
15 1000000÷2000×80%=400, and the corresponding 400-600 times for the prevention and treatment of citrus scab The dilution factor of the solution
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In the same way, you can calculate the correct amount of water for the preparation according to the conversion method of the first labeling method. .
Finally, Lao Hei would like to remind everyone here, although generally when we buy pesticide products, the owner of the agricultural material shop will indicate the corresponding amount of each pesticide, but if you can learn the labeling method of the international unit system on the pesticide packaging Of course, it couldn’t be better
.