Non-fumigant nematicides are formulated as liquids or water-soluble granules that are moved through the soil by water. Many of these products must be incorporated with soil or carried by water to be effective because they often inhibit nematodes through direct contact. Conversely, some non-fumigant nematicides are systemic (example: Vydate), meaning that the active ingredient is taken up by the plant and translocated to other parts of the plant. Nevertheless, most systemic nematicides, such as Vydate, are thought to primarily inhibit nematode damage through direct contact with the nematode in the soil profile, emphasizing the importance of adequate application uniformity to attain effective management. Generally, non-fumigant nematicides have a narrower spectrum of activity relative to that of soil fumigants, often preserving beneficial soil organisms responsible for essential soil ecosystem functioning, including nutrient cycling and natural regulation of pathogens and pests. Non-fumigant nematicides can be subdivided into two broad categories, chemical non-fumigant nematicides and biological non-fumigant nematicides.
Chemical nematicides inhibit nematodes through the action of synthetic compounds. Such nematicides can be divided into three different pesticide classes: carbamates, organophosphates, and 3-fluorine nematicides. Table 1 lists characteristics of active ingredients in chemical nematicides. Table 2 lists chemical nematicides currently registered for use in Florida on specific vegetable crops.
Carbamate nematicides available for vegetable production include Vydate L (Corteva Agriscience; active ingredient: oxamyl) and Vydate C-LV (Corteva Agriscience; active ingredient: oxamyl). These products are restricted-use pesticides and have a high level of toxicity towards non-target organisms (Gallego et al. 2019).
Organophosphate nematicides available for vegetable production include MOCAP 15G (AMVAC Chemical Corporation; active ingredient: ethoprop), MOCAP EC (AMVAC Chemical Corporation; active ingredient: ethoprop) and Counter 20G (AMVAC Chemical Corporation; active ingredient: terbufos). These products are restricted-use pesticides and have a high level of toxicity towards non-target organisms.
Three-fluorine nematicides are a relatively new class of reduced-risk pesticides available to vegetable producers and include products such as Nimitz (ADAMA Agricultural Solutions; active ingredient: fluensulfone) and Velum Prime (Bayer Crop Science; active ingredient: fluopyram). These products are safer to apply than carbamate and organophosphate nematicides and have significantly less toxicity towards most non-target organisms; however, fluopyram has been shown to reduce beneficial nematode populations densities in soil (Waldo et al. 2019).
Biological nematicides inhibit nematodes through the use of natural compounds produced by microorganisms and plants. Such nematicides can be divided into microbe-based nematicides and plant-based nematicides. Table 3 lists biological nematicides currently registered for use in Florida on specific vegetable crops.
Microbe-based nematicides use the activity of microorganisms to suppress plant-parasitic nematodes. Products such as Majestene (Marrone Bio Innovations; active ingredient: heat-killed Burkholderia rinojensis strain A396) use a suspension of secondary metabolites produced by an antagonistic soil bacterium. Other products, such as MeloCon WG (Certis USA; active ingredient: Purpureocillium lilacinus strain 251) use live organisms that suppress hatching of nematode eggs.
Plant-based nematicides use the activity of a diverse range of natural compounds produced by plants to suppress nematodes. This includes products such as Dazitol (Champon Millennium Chemicals Inc.; active ingredients: capsaicin and essential oil of mustard) and NemaKill (Excel Ag, Corp.; active ingredients: cinnamon oil, clove oil, and thyme oil).
Non-fumigant nematicides available for vegetable production in Florida include two broad categories, chemical nematicides and biological nematicides. Chemical nematicides can be divided into three pesticide classes: carbamates, organophosphates, and 3-fluorine nematicides. Biological nematicides include both microbe-based and plant-based products. Refer to EDIS publication ENY-065, Fumigant and Non-fumigant Nematicides labeled for Agronomic Crops in Florida (https://edis.ifas.ufl.edu/in395) for a list of nematicides registered for use on row crops in Florida. Refer to EDIS publication ENY-012, Soil-Inhabiting Nematodes, Phylum Nematoda (https://edis.ifas.ufl.edu/in138) for more information on nematode biology. For further information on nematode management, go to the Florida Nematode Management Guide (https://edis.ifas.ufl.edu/topic_nematode_management).
Gallego, S., M. Devers-Lamrani, K. Rousidou, D. G. Karpouzas, and F. Martin-Laurent. 2019. "Assessment of the effects of oxamyl on the bacterial community of an agricultural soil exhibiting enhanced biodegradation." Sci. Total Environ. 651: 1189–1198.
Waldo, B. D., Z. J. Grabau, T. M. Mengistu, and W. T. Crow. 2019. "Nematicide effects on non-target nematodes in bermudagrass." J. Nematol. 51: 1–12.
Characteristics of chemical nematicides registered for vegetable crop use.
Chemical nematicides registered for specific vegetable crop use.
Biological nematicides available for specific vegetable crop use.