Spinetoram

Spinetoram belongs to a class of insecticides that balances high efficacy against difficult pests with a significantly more favorable toxicological and environmental profile than traditional organophosphates or carbamates.

Spinetoram is not a single molecule, but a mixture of two main components (Spinetoram J and Spinetoram L), which ensures its stability and potency.

Common name: Spinetoram

Number CAS: 935545-74-7

Gross Chemical Formula:

Component J: C42H69NO10

Component L: C43H69NO10

Chemical class: spinosyns (IRAC Group 5)

Development history

Spinetoram was developed by Dow AgroSciences (now Corteva Agriscience). It is a semi-synthetic derivative of the fermentation of the soil bacterium Saccharopolyspora spinosa.

Unlike its "older brother," Spinosad, spinetoram underwent chemical modifications (hydrogenation and ethylation) to increase its photostability (resistance to sunlight) and extend its residual activity in the field. In 2008, it received the EPA Green Chemistry Challenge Award for its design focused on low environmental impact.

Key business names

In the Brazilian and global markets, the best-known products formulated with spinetoram are:

• Delegate (main focus on diverse crops such as citrus, apples, tomatoes)

• Exalted (used in large-scale crops such as soybeans, corn, and cotton)

Mechanism of action

Spinetoram acts on the insect's nervous system. It is an allosteric modulator of nicotinic acetylcholine receptors (nAChR).

How it works in practice:

1. The insect comes into contact with or ingests the product.

2. The spinetoram binds to a specific site on the nerve receptor, keeping it permanently open.

3. This causes hyperexcitation of the nervous system, leading to tremors, paralysis, and ultimately, the insect's death within a few hours (although feeding stops almost instantly).

Control spectrum

It is effective against pests that have chewing or scraping mouthparts, especially:

Thysanoptera: thrips (Frankliniella occidentalis).

Lepidoptera: caterpillars, such as Spodoptera frugiperda e Helicoverpa armigera.

Diptera: leaf miner (Liriomyza spp).

Psyllids: diaphorina citri.

Compatibilities and interactions

Tank mixing: It generally exhibits good compatibility with most fungicides and insecticides. However, mixing with extremely alkaline reaction products (such as Bordeaux mixture or some high-pH foliar fertilizers) should be avoided, as this may degrade the molecule.

Adjuvants: The use of oils or surfactants recommended by the manufacturer usually improves translaminar penetration (ability to pass through the leaf), increasing effectiveness against thrips and leaf miners.

Resistance: Scientific literature points to cases of resistance to spinetoram in countries such as Brazil, China, Pakistan, the United States, and others for insects: Frankliniella occidentalis (doi.org/10.1016/j.cropro.2022.106168); Frankliniella occidentalis (doi.org/10.1093/ee/nvac053); Spodoptera frugiperda (doi.org/10.1002/ps.5812); Thrips palmi (doi.org/10.1111/eva.12996); Tuta absoluta (doi.org/10.1016/j.pestbp.2025.106659Therefore, it is important to alternate active ingredients, as indicated by the Insecticide Resistance Action Committee (IRAC). 

Other technical issues

sitophilus oryzae e Tribolium castaneum These are serious pests of stored food. [...] Exposure to the bacterial formulation spinetoram, the pyrethroid deltamethrin, and high temperature are effective treatments, but their effects on certain species, when used alone or in combination, are poorly understood. This study evaluated the isolated and combined effects of spinetoram, deltamethrin, and heat on adult mortality of sitophilus oryzae e Tribolium castaneum[...] We conclude that prior exposure to deltamethrin and spinetoram may reduce heat tolerance, allowing for pest management with shorter exposure durations and consequently reducing thermal energy costs. Future experiments should address the limitations identified in this study to improve management and evaluate success under field conditions. - doi.org/10.1016/j.jspr.2025.102797 - 

Thrips control relies primarily on insecticide application. However, the effective implementation of chemical control is hampered by varying levels of insecticide resistance among species and populations. In this study, we investigated the susceptibility of five thrips species infesting vegetables to a commonly used insecticide, spinetoram, and determined the frequency of the G275E mutation at the target site in a major vegetable-producing region in China. Among the 27 populations tested, Thrips palmi showed the lowest susceptibility, with LC50 values ​​ranging from 21,15 to 136,40 mg/L and a mutation frequency of 52,08% to 93,75%. Three populations of Frankliniella occidentalis They presented LC50 values ​​of 7,44 to 11,24 mg/L, while a fourth population was significantly more susceptible (1,75 mg/L). A G275E mutation frequency of 15,8% was detected in one of the four populations. FrankliniellaIn contrast, the populations of Tabaci Thrips, Megalurothrips usitatus e Frankliniella intonsa They exhibited relatively low LC50 values ​​(0,39–1,44 mg/L, 0,41–7,98 mg/L and 0,03–1,24 mg/L) and a mutation frequency of 0%, indicating that these species remain largely susceptible to spinetoram. - doi.org/10.1016/j.cropro.2025.107398 -

The fall armyworm (Spodoptera frugiperdaSpinetoram has emerged as a major global pest of maize and other crops. Spinetoram, a widely used spinosynin insecticide, has played a central role in its management; however, increasing reports of resistance threaten the long-term sustainability of this compound. This review synthesizes current knowledge on spinetoram resistance in Spodoptera frugiperda, encompassing field reports, underlying molecular mechanisms, and emerging diagnostic approaches. Evidence of resistance has been reported in Brazil, while studies in China and Pakistan indicate emerging resistance. - doi.org/10.1002/ps.70847 -

The inheritance pattern of resistance Spodoptera frugiperda Spinotoram was characterized as autosomal, incompletely recessive, and polygenic. Cross-resistance between spinosyns was confirmed in Spodoptera frugiperda. The importance of this information for implementing insect resistance management strategies is discussed in this article. - doi.org/10.1002/ps.5812 -

The adaptive cost associated with insecticide resistance and its magnitude can be affected by several environmental factors, such as temperature. Insect pests can express different phenotypes in response to modified environmental conditions. In this context, we investigated the impact of temperatures of 18, 22, 28, and 32 °C on the magnitude of adaptive costs associated with resistance. Different biological parameters were compared between near-isogenic strains resistant to chlorantraniliprole (Iso-Diam) and spinetoram (Iso-Spin). Spodoptera frugiperda and the lineage of Spodoptera frugiperda susceptible in the laboratory (Sus). [...] Significant differences were observed in the fertility life table parameters of the Iso-Diam and Iso-Spin strains compared to the Sus strain at temperatures of 18 and 28 °C. The relative fitness of the Iso-Diam and Iso-Spin strains at 18 °C was 0,60 and 0,80, respectively. At 28 °C, the relative fitness of the Iso-Diam and Iso-Spin strains was 0,53 and 0,88, respectively. Resistance rates of spinetoram- and chlorantraniliprole-resistant strains were higher at temperatures of 18 and 32 °C. These results indicate that the adaptive cost and susceptibility to chlorantraniliprole and spinetoram in Spodoptera frugiperda They are affected by different temperatures. - doi.org/10.1016/j.cropro.2025.107285 -

Spinosin insecticides (spinosad and spinetoram) have been widely used to control various agricultural pests, including the fall armyworm. Spodoptera frugiperdaMutations in the α6 subunit of the nicotinic acetylcholine receptor (nAChRα6) have been reported to confer high levels of resistance to spinosyns in various insect pests. - doi.org/10.1016/j.pestbp.2022.105191 -

In this study, we performed a molecular docking analysis between CYP6AB328 and spinetoram. Our docking analysis demonstrated good binding affinity between CYP6AB328 and spinetoram, with an energy of less than −6,0 kcal/mol. Metabolomic analysis showed that recombinant CYP6AB328 exhibited substantial metabolic activity relative to spinetoram-J (16,62%) and spinetoram-L (12,42%), which were metabolized into two products, N-desmethyl spinetoram J and N-desmethyl spinetoram L, respectively. We also found that the strain of Tuta absoluta A strain resistant to spinetoram, selected in the laboratory, showed 34 times greater cross-resistance to spinosad, but little or no cross-resistance to imidacloprid (1,26 times), chlorantraniliprole (1,12 times), deltamethrin (1,76 times), and avermectin (1,34 times). Meanwhile, the expression level of CYP6AB328 showed a positive correlation with spinetoram resistance in four field populations of Tuta absoluta. - doi.org/10.1002/ps.70849 -