1. Introduction
In modern agricultural production, pesticides are an important means to ensure crop yield and quality. However, pesticides face many challenges during use, such as low pesticide utilization, uneven distribution on the surface of target crops, and susceptibility to rainwater erosion, which not only causes pesticide waste but may also lead to environmental pollution and harm to non-target organisms. As an important type of pesticide adjuvant, silicone oil adjuvant can significantly improve the physical and chemical properties of pesticides and enhance the application effect of pesticides in agricultural production. This paper aims to deeply explore the effect of silicone oil adjuvants on the performance of pesticides and provide a theoretical basis for their rational application in the agricultural field.
2. Challenges faced by pesticide application
2.1 Low pesticide utilization rate
During the traditional pesticide application process, only a small amount of pesticides can actually act on the target organisms, and most pesticides are not effectively utilized due to drift, loss and other reasons. According to statistics, under conventional spray application methods, the effective utilization rate of pesticides is usually only 20% - 30%, which not only increases agricultural production costs but also causes waste of resources.
2.2 Uneven coverage
The coverage uniformity of pesticides on crop surfaces is poor, making it difficult to fully contact target organisms, resulting in poor control effects. Especially for some crops with special leaf structures (such as lotus-like surface), pesticide droplets tend to roll off and cannot form effective coverage.
2.3 Susceptible to rain erosion
If it rains within a short period of time after applying the pesticide, the pesticide will be easily washed away by the rain, reducing the retention time and effective concentration of the pesticide on the crop surface, thus affecting the control effect. Sometimes, the pesticide needs to be re-applied, further increasing the amount of pesticide used and cost.
3. Characteristics of silicone oil additives
3.1 Low surface tension
Silicone oil additives have extremely low surface tension, usually below 20 mN/m, which is much lower than the surface tension of water (about 72 mN/m). This allows the pesticide droplets with added silicone oil adjuvant to spread quickly on the crop surface, greatly increasing the coverage area of the pesticide.
3.2 Good wettability
With its low surface tension, silicone oil adjuvant can significantly improve the wettability of pesticide droplets on crop surfaces and target organisms, making it easier for droplets to adhere to the hydrophobic leaf surface, overcoming obstacles such as the wax layer on the crop surface. , increasing the contact probability between pesticides and target organisms.
3.3 Strong permeability
Silicone oil adjuvants can change the interfacial properties of pesticide droplets and enhance their penetration ability. It can help pesticides penetrate the cuticle of plant epidermis or the wax layer of insects faster, thereby increasing the conduction rate of pesticides in plants and the effectiveness of pesticides in insects.
3.4 Chemical stability
Silicone oil additives have good chemical stability. When mixed with pesticides, they generally do not react chemically with the active ingredients of the pesticides, ensuring the stability of the chemical properties of the pesticides and facilitating the storage and use of pesticide preparations.