Nematodes control

Cook, R. and Evans, K. (1987) Resistance and tolerance. In Brown, R.H. and Kerry, B.R. (eds) Principles and Practice of Nematode Control in Crops. Academic Press, Sydney. 

Taken as a whole, these observations show that parasite lines differ in an immune-dependent manner in their infection/expulsion kinetics. Furthermore, there is heritable variation in survival and fecundity in previously exposed hosts and quantitative variation in the immune response that selected parasite lines elicit. Again, taken as a whole, these observations have the necessary corollary that variation in these traits exists not only in laboratory-maintained isolates but also in helminth species in nature. The phenotypes under consideration here (infection/expulsion kinetics, survival, fecundity) are multifactorial life-history traits. Understanding the basis of variation in the components and interplay of these complex, immune-responsive phenotypes must be of crucial relevance to understanding the immunology of infections of parasitic nematodes. This is of particular relevance in view of current attempts to develop immunological methods of nematode control. 

Waller, P. J. and Thamsborg, S. M. (2004). Nematode control in green ruminant production systems . Trends in Parasitology, 20(10), 493-497. 

Chitwood D J (2002), Phytochemical based strategies for nematode control , Annu Rev Phytopathol, 40, 221-249. 

This comprehensive definition makes it elear that a wide number of substances may be eonsidered to be pestieides, and that the eommonality among all pestieides is their ability to provide eontrol over pests. A variety of classifications for pesticides have been developed that are specific for the type of pest controlled. Insecticides, for example, are pesticides that control insects, while herbicides control weeds and fungicides control plant diseases (molds). In addition to these major classifications of pesticides, there are many other classifications. These include nematicides (for nematode control), acaracides (mite control), rodenticides (rodent control), molluscicide (snail and slug control), algacides (algal control), bacteriocides (bacterial control), and defoliants (leaf control). 

ClandoSan is a chitin protein found in crasta-cean shells and is labeled for nematode control. ClandoSatf is a new product still being evaluated. The product acts to stimulate the growth of certain soil microorganisms that produce chitanase and other enzymes that destroy plant-pathogenic nematodes. 

Ivency or emulsification of beeswax, aqueous solubility, and vapor pressure are completely correlated with nematocidal efficacy as determined in laboratory tests. The correlation is not complete when field efficacy is considered. Thus carbon tetrachloride, benzene, and toluene should be good nematocides, but have not proved satisfactory in field tests. Likewise carbon disulfide, while a sound nematocide under optimum conditions, requires, for satisfactory nematode control, a greater quantity than would be expected on the basis of its solubilities and solvency. The answer may lie in the lack of polarity of these molecules. 

Stafford, K. and Coles, G.C. (1999) Nematode control practices and anthelmintic resistance in dairy calves in the south west of England. Veterinary Record 144, 659-661. 

Plants belonging to 57 families have been shown to possess nematicidal properties (Bridge, 1996). Crop rotation (crops planted in sequence) and intercropping (crops planted together) have both shown potential for reducing populations of parasitic nematodes. Cover crops are a type of rotation employed as an alternative to leaving land fallow, and are usually not cash crops. Many plants have been used as rotation or cover crops for plant-parasitic nematode control (Table 1). 

Research by Soler-Serratosa et al. (1996) using combinations of thymol and benzaldehyde for root-knot and cyst nematode control on soybeans showed that both compounds exhibited wide spectrum nematicidal activity with Meloidogyne spp. and Dorylaimid nematodes being more sensitive than cyst nematode and nonparasitic nematodes (Soler-Serratosa et al., 1996). In addition to the direct toxicity of these compounds to nematodes, it was hyopothesized that stimulation of beneficial microflora by the compounds or their products, altered host response, and a deleterious physicochemical environment may all contribute to reduced gall formation (Soler-Seratosa et al., 1996). 

Sipes, B.S. Pre-plant and post-plant pesticides for nematode control in pineapple. Acta Horticult 1997 425 457-464. 

Morris, J.B., Walker, J.T. Non-traditional legumes as potential soil amendments for nematode control. J Nematol 2002 34 358-361. 

Prevention and Control Plant resistant cultivars, when available. Rotate crops. Avoid spreading soil from infested to noninfested areas. Soil solarization helps to reduce nematode populations. Or try a cover crop of marigolds, and turn them into the soil at the end of the season. Incorporate plenty of organic matter into the soil to promote natural nematode-controlling microorganisms. Drenching the soil with neem may also help. 

How to Use To control nematode pests on lawns and under trees, apply crushed shells at a rate of 5 pounds per 200 square feet, then water them in. Be sure to include a source of nitrogen. In vegetable gardens, till chitin into the soil at the same rate. Or, apply it in bands along the row at one-half the rate. Chitin breaks down slowly and provides nematode control for 1 year with a single application. 

The least costly and, ultimately, most effective approach toward solving this problem is preventative. At the federal level, EPA must develop more rigorous pesticide registration requirements. Pesticides with a high potential for leaching should not be registered for nematode control. Industry can play a lead role in... 

Mass production of inoculum for nematode control has not yet been upscaled industrially. To assure optimal longevity and infectivity of the conidia, the fungi are generally grown in solid-state surface cultures see under Pochonia chlamydosporia. For the production of Hirsutella rhossiliensis inoculum, stirred cultures in 5-L containers were used (Patel et al., 2001). 

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