Seed dressing

Lindane is used predominately as a seed dressing and soil insecticide, for the control of ectoparasites of humans and domestic animals, for the control of locusts and grasshoppers, and as a residual spray to control the Anopheles vectors of malaria. Because of its relatively high volatility it is useful to control wood-boring insects of timber, fmit trees, and ornamental plants. The mode of action is not well understood but is thought to be competitive blocking of the y-aminobutyric acid (GABA) transmitter of synaptic nerve transmission. 

The first commercially available HCH insecticide sometimes misleadingly called benzene hexachloride (BHC) was a mixture of isomers, principally alpha HCH (65-70%), beta HCH (7-10%), and gamma HCH (14-15%). Most of the insecticidal activity was due to the gamma isomer (Figure 5.1), a purified preparation of which (>99% pure) was marketed as lindane. In Western countries, technical HCH was quickly replaced by lindane, but in some other countries (e.g., China) the technical product, which is cheaper and easier to produce, has continued to be used. HCH has been used as a seed dressing, a crop spray, and a dip to control ectoparasites of farm animals. It has also been used to treat timber against wood-boring insects. 

The relatively high vapor pressure of most OPs limits their persistence when sprayed on to exposed surfaces (e.g., on crops, seeds, or farm animals). Some, such as chlorfenvinphos, have relatively low vapor pressure, and consequently tend to be more persistent than most OPs. Chlorfenvinphos has been used as a replacement for OC compounds both as an insecticidal seed dressing and as a sheep dip. 

The environmental fate and behavior of compounds depends on their physical, chemical, and biochemical properties. Individual OPs differ considerably from one another in their properties and, consequently, in their environmental behavior and the way they are used as pesticides. Pesticide chemists and formulators have been able to exploit the properties of individual OPs in order to achieve more effective and more environment-friendly pest control, for example, in the development of compounds like chlorfenviphos, which has enough stability and a sufficiently low vapor pressure to be effective as an insecticidal seed dressing, but, like other OPs, is readily biodegradable thus, it was introduced as a more environment-friendly alternative to persistent OCs as a seed dressing. 

OPs are often applied as sprays. Commonly, the formulations used for spraying are emulsifiable concentrates, where the OP is dissolved in an organic liquid that acts as a carrier. OPs are also used as seed dressings and as components of dips used to protect livestock against ectoparasites. Some highly toxic OPs have been incorporated into granular formulations for application to soil or to certain crops. 

Fuchs, P. (1967). Death of birds caused by application of seed dressings in the Netherlands. Mededel Rijksfacultait Landbouwweetenschappen Gent 31, 855-859. 

Turtle, E.E., Taylor, A., and Wright, E.N. et al. (1963). The effects on birds of certain chlorinated insecticides used as seed dressings. Journal of the Science of Food and Agriculture 14, 567-577. 

Use pattern Hymexazol is used for the control of soil-borne diseases for rice, sugar beet, spinach, pea, cucumber, watermelon, grass, etc. Applied as a soil drench or by soil incorporation and used as a seed dressing for sugar beet. Hymexazol also exhibits some plant growth stimulation activity. 

A seed dressing method based on electrons was developed and tested by Lindner et al. (1996) and Schauder (2003) as a direct method to improve seed quality and remove/reduce seedborne disease inocula. Electron seed dressing effectively removed common bunt spores (Tilletia caries) and reduced bunt levels compared to untreated seeds in field trials. However, its efficacy against M. nivale has not, as yet, been confirmed. Since this technique has potentially negative effects on germination rates of seed, it is limited to surface treatments (Jahn, 2002 Jahn et al., 2005). 

Dabkevicius Z and Semaskiene R (2002), Control of ergot (Claviceps purpurea (Fr.) Tul.) ascoscarpus formation under the impact of chemical and biological seed dressing , Plant Protect. Sci., 38 (2), 681-683. 

North America Feather From areas with mercury-treated seed dressing ... 

Mercury is consumed in the manufacture of organomercurials, which are used in agriculture as fungicides, e.g., for seed dressing. 

Uses. Fungicides in seed dressings, folial sprays preservative solutions for wood, paper pulp, textiles, and leather... 

C.-G. Ros6n, H. Ackefors, and R. Nilsson, Seed Dressing Compounds Based on Organic Mercury—Economic Aspects and Health Hazards, Svensk Kemisk Tidskrift7, no. 8 (1966) 8-19. 

The imidazole derivative, prochloraz, has a peculiar feature compared to the azole derivatives. The nitrogen atom in the 1-position of the imidazole is bonded to a carbamoyl group and not to alkyl. This compound, which is regarded as a tetrasubstituted urea, has a very broad spectrum and can be used in cereals both as a seed dressing and a foliar fungicide (9). 

---