Root elongation test

Isolated, crystallized and characterized. Pure commercial samples of each of the three phenols and p-benzoqulnone (VIII), the oxidation product of hydroqulnone (Included to evaluate the possible vivo oxidation of hydroqulnone), were tested In lettuce and leafy spurge root elongation tests and In leafy spurge cell cultures (Table II). 

Lactuca sativa, 120 h inhibition of germination and root elongation test (Dutka, 1989a) ... 

It is for these reasons that much of the experimental work on metal tolerance has relied on laboratory tests for tolerance that seek to isolate the toxic effects of the metal from other possible factors. The most widely used technique is the root elongation test, in which the toxic effects of metals on roots are used to assess tolerance. Cuttings or tillers (for grasses) are grown in solutions containing varying concentrations of the... 

Total cyanide Gross alpha and beta radioactivity Root elongation test... 

Seed germination/root elongation toxicity test... 

Four bioassays a) 30 min acute bacterial test (Vibrio fischeri) b) 8d growth rate aquatic plant test (Lemna minor) c) 72h germination plant test (Lepidium sativum) and 8d root elongation plant test (Lepidium sativum) d) 72h germination plant test (Brassica rapa) and 8d root elongation plant test (Brassica rapa) Municipal and industrial solid waste leachates originating from landfills Unspecified pretreatment... 

Linder, G., J.C. Greene, H. Ratsch, J. Nwosu, S. Smith, and D. Wilborn. 1990. Seed germination and root elongation toxicity tests in hazardous waste site evaluation Methods development and applications. In Plants for Toxicity Assessment, ASTM STP 1091, J.G. Pearson, R.B. Foster, and W.E. Bishop, Eds. American Society for Testing and Materials, Philadelphia, PA, 177-187. 

Wang, W. 1987. Root elongation method for toxicity testing of organic and inorganic pollutants. Environ. Toxicol. Chem. 6 409 14. 

USEPA. 1992a. Seed germination/root elongation toxicity test. U.S. Environmental Protection Agency. Title 40 Chapter 1, subchapter R of the Code of Federal Regulations, pp. 419M22. 

Higher plants have been used in tests for genotoxicity that are discussed in more detail in Section 7.3.3. For example, the onion Allium cepa has been used not only in root elongation assays for toxicity but to detect mitotic, cytoki-netic, and chromosomal aberration in the root tips (Fiskesjo 1995). A micronucleus assay that detects chromosome breaks in Tradescantia sp. planted in areas suspected of pollution has been used (Sandhu et al. 1991) and suggests the possible value of such assays in the terrestrial environment or as an indicator of atmospheric pollution. 

USEPA OPPTS 850.4200 (1996) Ecological Effect Test Guidelines, 850 Series (Proposal) Seed Germination/Root Elongation Toxicity Test. 

In the Bueehe-Halpin theory the necessity of a strong filler-rubber bond follows naturally from the requirement of a low creep compliance. On the other hand the hysteresis criterion of failure, Eq. (32), does not make the need for filler-rubber adhesion immediately obvious. It is clear, however, that Hb cannot exceed Ub. In absence of a strong filler-rubber bond, the stress will never attain a high value the only way for Ub to become large would be for eb to increase considerably. There is no reason, however, why under these conditions eb should be much greater than in the unfilled rubber at the same test conditions and, in any case, it will be limited by the so-called ultimate elongation . This is the maximum value of eh on the failure envelope and is a fundamental property of polymeric networks. The ultimate extension ratio is given by theory (2/7) as the square root of the number of statistical links per network chain, n,... 

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