The rapid development of OD formulations in China, more than 1659 registered, herbicides accounted for 95.6%

With the improvement of people's living standards, environmental sustainable development has become the policy orientation of the country, and the development of pesticide in the direction of green environmental protection is the general trend. OD has become a hot spot in the development of conventional formulations, with the increase of enterprise registration varieties, but also attracted a large amount of investment and more attention of auxiliary enterprises, will promote the rapid development of the formulation.

The earliest varieties of OD registered in China are only 4% Nicosulfuron OD, but in recent years, OD has been rapidly developed, in 2004, there are only 3 varieties of OF registered in China. They are 2.5% Penoxsulam OD (Dow), 10% Sulcotrione OF and 10 billion spores /mL Metarhizium anisopliae OF, while the number of OD (including OF) registered in 2009 has reached 149. There were 87 OD and 62 OF

As of September 2023, the number of OD formulations registered in China has increased rapidly to 1659, of which herbicides are the main, reaching 1586, accounting for 95.6%, and about 125 active ingredients and mixtures are registered. Insecticides ranked second, with 56 species registered; There are only eight varieties of fungicides, which is almost negligible.

Among the pesticide registration formulations, neonicotinoid insecticides and biological pesticides were the main formulations, among which 28 neonicotinoid insecticides were registered, and 17 were mainly mixed Dinotefuran, accounting for 60.7% of neonicotinoid registered products. There were 13 biological pesticides, 8 pyrethroids and 6 abamectin. The results show that OD can be prepared by all the mainstream insecticides, but there are few registered insecticides, and their development potential is great.

In the herbicide registration formulations, Nicosulfuron, Mesotrione, Atrazine, Penoxsulam, Cyhalofop-butyl, Mesosulfuron-methyl and so on were the main varieties.

There were more single-agent registered formulations in herbicides, such as Nicosulfuron, Penoxsulam, Cyhalofop-butyl and Mesosulfuron-methyl, etc., while there were only 7 single-agent registered formulations of Atrazine, but the mixed registered formulations took the lead. Except for Mesosulfuron-methyl, the other formulations were more than 100. This is in line with the Chinese national situation of "unifying the world" of mixtures, especially the following mixtures are more registered formulations: 109 mixtures of Atrazine·Nicosulfuron, 66 mixtures of Mesotrione·Atrazine, and 58 mixtures of Penoxsulam·Cyhalofop-butyl.

Nicosulfuron, as the leader of OD, is the inevitable choice of pesticide formulation. The earliest OD formulation in China is 4% Nicosulfuron OD (Nicosulfuron is a special weed herbicide of the corn field sulfonylureas family that was discovered by Ishihara Sangyo Kaisha, Ltd in the mid-1980s). 1987-1988 Ishihara Sangyo Kaisha, Ltd and the United States DuPont company jointly developed, and has obtained various patents in the world, in the early 1990s in China to obtain registration).

Nicosulfuron is extremely sensitive to water, oil and water are not soluble, very unstable in water, but very stable in oil, if developed for some solid formulations, the efficacy is not good when used, generally need to add oil synergies to improve the efficacy, and processing into OD can improve the penetration of pesticide active ingredients, to ensure that its internal absorption activity is fully played. Therefore, OD is the best choice of Nicosulfuron formulation.

OD is also the best formulation of Penoxsulam. The chemical structure of Penoxsulam contains 5 fluorine atoms, which greatly enhances the lipophilicity of the active ingredient. If it is processed into a SC, because the applied crops are paddy fields, if the control objects are monocotyledon weeds such as barnyard grass and sandgrass weeds, and these weeds are difficult to wettability plants like paddy, and the amount of additives used in conventional SC is small, when the drug solution is sprayed on the target, due to the amount of additives is small, the surface tension is large, and the adhesion is poor, the formulation is not easy to be wettability and spread. Easy to roll off, can not be effectively deposited on the target, its prevention effect can be imagined.

The processing into Penoxsulam OD can basically solve the above drawbacks, and Penoxsulam is an endosorption conductive herbicide, and the oil-based medium can quickly help the active ingredients to conduct through the crop epidermis and enter the target interior, thereby improving their permeability, adhesion and absorption, and achieving the purpose of improving drug efficacy.

There is also evidence that herbicides are the preferred development formulation for OD, as Nicosulfuron, Atrazine and mesotrione are all applied to dryland crops such as maize, Mesosulfuron-methyl is applied to wheat fields, and Penoxsulam and Cyhalofop-butyl are mainly applied to paddy fields. Compared with other vegetable oils, the viscosity of methyl oleate is lower, and it is relatively easy to emulsify and prepare, and it is also safer for dryland crops and paddy fields. So it makes sense that the development of OD began with herbicides.

OD has incomparable advantages over other pesticide formulations, and can solve many insurmountable defects of existing formulations, so that the formulation has great development potential and a promising future.