Pesticides play a significant role in the production of stable crops output and are important in agricultural production. The application of pesticides is a common in agricultural production.With the improvement of people’s living standards and the development of society, food safety, production safety and environmental safety has get more and more attention from different parties. Like in China, government has carried out a plan of zero growth in pesticide use.
The zero increase in pesticide is mainly in two aspects. On one side, the using amount of pesticide has dropped, and one the other side the pesticide utilization rate has improved. Early, manual sprayers were mainly used in China for single farmers, and the amount of spary was large, but the prevention effect was not so good and the utilization rate was only around 25%, as most of the pesticides are lost to the air or soil.
While in recent years, the application of silicone adjuvant has taken changes in the pesticides formulation and application technology. With its outstanding effect in permeability, expansion, wetting, foaming, foam suppression, bubble stabilization and good compatibility performance, the utilization rate and prevention rate has been improved significantly. Thus, the using amount of pesticides can be reduced by 30%-50%. The add of silicone adjuvant in agriculture pesticides also save water, lessen pesticide residues, and reduce laber cost. And now agriculture adjuvant are widely applied in the agriculture production.
Today, from the characteristics and application of silicone adjuvants, it is hoped that the users can have a deep understanding of silicone adjuvants and to make reasonable use of it. This can help reduce agricultural production costs and improve the effectiveness.
Excellent performance of silicone adjuvants
The properties of agriculture silicone adjuvants mainly include the following three aspects: wetting, expansion and permeability.
1. Excellent wetting properties
Moisture resistance structure of composition is very normal in plant leaves, plant stems and insect epidermis. And on the surface of leaf, there is a negative charge, which makes pesticide liquid repellent and not easy to wet. Normally, when the pesticide spray has lower surface tension than that of leaf, the spray can moisten the leaf surface easily. On the contract, the pesticide spray will gather on the plant surface if its surface tension is higher, thus, the droplets of spray will concentrate on the leaf and roll down.
Silicone adjuvant has very low surface tension. After adding it into pesticide, it can make the pesticide spray moisten all the leaf surface and insect epidermis very easily. It can largely increase the contact surface of pesticide liquid to the target organisms, lessen the loss of pesticides and improve the utilization rate
2. Superior expansion
The agriculture silicone adjuvant has superior expansion performance. After adding the silicone adjuvant into pesticide liquid, the area of expansion is around 10 times of the one without the silicone adjuvant. This superior expansion can make the pesticide liquid attached on the foliar and even make it onto the pests hidden in the fruit gap. Thus there can be direct contact of the spray liquid and pests may be killed.
3. Prime permeability
Stoma is one of the main approaches where the pesticide liquid spray permeate into the plant. Silicone adjuvants can help the pesticide liquid penetrate into the epidermis through the stoma easily. Also the absorption rate can be faster. Some studies show that silicone adjuvant has effective synergism on veramycin. It can take the pesticide liquid into the microscopic hiding place of pests. Then the pesticide liquid with silicone adjuvant will be absorbed by the leaf surface and get into the plant epidermis. It can also prolong the staying period of pesticide liquid, which is longer than pesticide liquid with mineral oil adjuvant.
Application of silicone adjuvants in pesticides
Silicone adjuvants can be used in pesticides as spray amendments, foliar absorptive aids or activators, etc. And it can be applied together with pesticides, herbicides, foliar fertilizer,or growth regulators.
1.Application in pesticides or herbicides
Silicone adjuvants are added into pesticides or herbicides. The herbicide solution is sprayed onto the leaves and stems of weeds, it will quickly penetrate into the cuticle and cytoplasmic membrane, and then transmitted to all the other parts of plant. After weeds get injury, the leaves and stems will deform and get dead. This can effectively improve the grass killing rate and prevention efficiency. This also contribute to the water saving and labor saving.
2.Application in foliar fertilizer
Foliar fertilizer is an efficient and fast way to supply nutrients to the plants. But foliar fertilization is not easy to penetrate into plants due to the impermeability of the plant epidermis to inorganic nutrient ions. So the infiltration through stoma is a good way for foliar fertilization. The adding of silicone adjuvants can improve the absorption of plants through stoma permeability and thus strengthen the fertilizer utilization rate.
3.Application in growth regulators
Silicone adjuvants can reduce the using amount and improve the using effect. For example, eryamycin is widely applied in citrus, but can easily antagonize with citrus. The use of agriculture silicone adjuvant can largely improve the function of eryamycin and the using amount can be reduced to 10%. The adding of agriculture silicone adjuvant to enolazole can improve its efficacy and moisture, as well as reduce the using amount and cost of enolazole.
4. Application in insecticide and mite killer
The stoma of insects is extremely similar to the foliar ones.The silicone adjuvant can reduce the surface tension of the insecticide solution, help the spray solution penetrate into the insect trachea. This is very meaningful for the insecticide aid and synergist.For example, with the add of silicone adjuvant, the effect of 45g /hm2 20% buthiok budweiser emulsion is same as that of 75g/hm2. This can significantly lessen the field dose of buthiok budweiser emulsion by 20%.
How to use silicone adjuvant efficiently
1.Suitable dosage of silicone adjuvant
At the condition of normal temperature of 25℃ and moisture 60%, The add of 0.5% -0.1% silicone adjuvant into herbicide solution, the using amount of silicone adjuvant can be decreased by 30%, but with similar effects as conventional dosage of herbicides. Under drought conditions, The adding of 0.1% silicone adjuvant into herbicide solution can obtain stable herbicide effect.
In pesticides and fungicide spray, the adding amount of silicone adjuvants is around 0.025% to 0.5% -0.1%. The spray with silicone adjuvants can increase droplet retention time, improve droplet dispersion and absorption. Thus the efficacy can be improved.
The adding amount of silicone adjuvant into plant growth regulator is 0.025%-0 .05%. And the amount of fertilizer and trace elements are 0.015% -0.1% of the growth regulator spray. This can help improve efficacy and fertility.
2.Using Principles (Scope of Use) of silicone adjuvants
The silicone adjuvant have good work in the formulation. But its price is also higher than other adjuvants The global brand of silicone adjuvant sells at high price and the cost from China brand is like half of Momentive or Dow. So, during the use, users have to pay attention on the using principles to have good effects with less cost.
1.Apply to the crops that is difficult to wet and less use on the easy moistened crops
For crops easy to be wet, such as celery, rape, spinach, beans, tomato, pepper and other fruits and vegetables, there is no need to use silicone adjuvant. As the use of conventional adjuvants can meet the requirements of wetting crops.For wax crops that are not easy yo be wet, silicone adjuvants are encouraged to be used. Wax crops include rice, wheat, cabbage, finch wheat and weeds without leaves. The use of silicone adjuvants can improve the effect of the spray.
2.Suitable for crops with hidden insect pests and diseases
For fruits like litchi, longan and grapes or vegetables like broccoli with hidden pests or germs, the adding to silicone adjuvants can make the pesticide spray better penetrating and spreading on the fruit gaps and leaves. So it can achieve the effects of eliminating pests or controlling germs.
3.Suitable for crops in rainy areas
In the rainy areas, the use of silicone adjuvants can maximize the wetting and spreading of pesticide spray. Also, it can enhance surface permeability, improve its resistance to rain washing, and greatly reduce possibility of the loss of expensive pesticide as well as decrease agricultural costs.
4.Suitable for UV sensitive pesticides or spray under strong summer light
For pesticides such as amimectin and methine amimectin benzoate, they are sensitive to ultraviolet light. The silicone adjuvants have super and rapid spreading capacity and can make almost instant stoma absorption. This can avoid photolysis, rapid evaporation and drying of the pesticide spray, and help in promoting the absorption of silicone adjuvants.
5.Pay attention to reasonable mixing
The use of some agriculture additives suppresses silicone effects; there are different additives used in the pesticide formulation. Some emulsifiers are antagonistic with silicone adjuvants and can not be used together. For example, acid compound emulsifiers such as 2201 # and 0206B# are suggested not to use together with silicone adjuvant as it is unfavourable to silicon-oxygen bond stability.
Notes for Use of Pesticide Silicone Adjuvants
The concentration and using amount should be strictly controlled. The appropriate concentration of silicone adjuvants with different kinds of pesticides is: herbicide 0.025% -0.15%, insecticide 0.025% -0.1%, fungicide 0.015% -0.05%, plant growth regulator 0.025% -0.05%. The using amount with some powerful pesticides and herbicides should be reduced to prevent pesticide damage.
The spray cannot be used under high temperature conditions. If the temperature is over 30℃, it is better not to add silicone adjuvants when spraying pesticide. At this moment, the crop stoma is highly open, and the silicone adjuvant activity is very strong. And this strong permeability can cause harm to crops. If to spray the pesticide on the fruit trees, do not spray it directly on the fruit. To prevent rust points or rust spots, it is better to spray the pesticide after the fruit is bagged.
It is better spay the pesticide once after the silicone adjuvant is mixed together with it. silicone adjuvants are easily to be decomposed in both acid and alkali conditions and most pesticide preparations are obviously acidic. So, it is suggested to use pesticide on spot after mixed with silicone adjuvants.
Add certain volume of defoaming agent,.The silicone adjuvant is relatively active and easy to produce excessive foam. During the application, it is suggested to be added to the pesticide bucket of the sprayer at last to avoid excessive mixing. This can reduce the foaming amount. Also the adding of defoaming agent also helps.
Summary of silicone adjuvants in agriculture
There are different silicone adjuvant products available in the market. We should choose the silicone adjuvants that have trisiloxane active ingredient higher than 90% to ensure its excellent performance.
The silicone adjuvants have very low surface tension, super spreading ability and rapid absorption through stoma.Reasonable use of silicone adjuvants can reduce the using amount of pesticide, improve the utilization rate of pesticides, reduce production costs, and lessen the environmental pollution of pesticides.
However, everything has two aspects. With improper use of silicone adjuvants, it can cause drug harm to the crops. For example, the wax layer of some leaves is thin, if the using concentration is increased to get better penetrating effect can cause drug harm. In addition, the silicone surface tension is very low and has strong permeability. After entering into the water, it is toxic to the fish and easy to damage the gill function. So it better to prevent the flow of farm water into the breeding pond, thus the fish in the pond can be survived from the drug harm from the improper use.
Therefore, in the use of silicone adjuvants, we must bear in mind the using amount, the using note, and the using principles of silicone adjuvants. We should apply the silicone adjuvants as per its characteristics, and play its important role in the formulation. With the right instruction of silicone adjuvants, it is believed that they can have good performance in the controling of pests, lower farmer’s cost as well as protect the environment. The different supplying choices from China silicone adjuvant producers also make the cost lower but with the similar application effects.