Application of Higher Plants

The use of hybrid poplar (Populus deltoides X P. nigra) has been examined in a few investigations at sites contaminated with creosote. There are several issues that complicate the interpretation of these results, including the physical state of the contaminants, the mechanism of uptake from the soil, and translocation and metabolism in the plants. These have seldom been addressed in studies of PAHs. 

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P-O-glucuronide conjugates (Nakajima et al. 1996), and it has been shown that 1-hydroxypyrene is highly toxic to the nematode Caenorhabditis elegans (Lambert et al. 1995). Both these important issues should be considered particularly in the application of higher plants to bioremediation (Section 8.1.1). 

Use of higher plants has attracted attention for the remediation of TCE-contaminated aquatic systems, and in particular the use of hybrid poplar (Newman et al. 1999). Although this was encouraged by the removal of labeled TCE to >90% using hybrid poplar under hydroponic conditions (Orchard et al. 2000), and the ability of hybrid poplar to metabolize TCE (Newman et al. 1997 Shang et al. 2001), there are additional considerations that must be evaluated to determine its general applicability. 

Merzlyak, M.N. et al., Application of reflectance spectroscopy for analysis of higher plant... 

There are regulations in place to cover the collection of microbes in Japan, but not the collection of higher plants and animals. Since 1968, efforts have been underway to conserve microbial samples and deposit them for patent application in the International Patent Organism Depository (IPOD)53 within the Patent Office. Protocols and their review are conducted by IPOD and forms are available online. No distinction is made between academic and... 

The application of these general principles to the study of reaction centers of bacteria and of PSI and PSII of higher plants will be discussed in the following sections. 

The development of toxic symptoms caused by urea herbicides depends on the particular herbicide, on the species of the plant and the application rate. Generally, the action of urea herbicides is not rapid, though after the application of higher doses chlorotic symptoms develop within a few days in sensitive plants such as beans. The death of the plants usually occurs within weeks. 

It is thought that borate ester cross-linking of pectin is necessary for the normal growth and development of higher plants. Thus, a deficiency of boron leads to the effects described above. Application of borate fertilizers such as borax (Na2[B405(0H)4] 8H20) to crops is therefore important. A balance has to be sought, however, because an excess of boron can be toxic to plants, and cereal crops are especially sensitive. 

Synechocystis 6803 is a convenient organism for genetically manipulating PSll. it can be readily transformed with exogenous DNA and is capable of photoheterotrophic growth on media supplemented with glucose when PSll function is impaired. Due to the similarities of the structures of the PSll components, any conclusions drawn from work on Synechocystis 6803 are applicable to higher plants. 

Krikorian, A.D. (1982) Biol. Rev. (Cambridge) 57, 151-218. Stewart, R.N. (1978) Symp. Soc. Devel. Biol. 36, 131-160. Chaleff, R.S. (1981) Genetics of Higher Plants. Applications of Cell Culture, Cambridge Press, Cambridge. Heslop-Harrison, J. (1967) Annu. Rev. Plant Physiol. 18, 325-348. 

Another possible approach is to keep the coolant pH constant over the whole length of the fuel cycle (Area B in Fig. 1.13.). In the so-called coordinated Li/B coolant chemistry introduced by Roesmer (1983), the starting lithium concentration of 2 ppm is continuously reduced, resulting in a pH of about 6.9 over the whole cycle. A third approach, which has been used experimentally, is to start with a high lithium concentration in excess of 2.2 ppm (e. g. 3.5 ppm in the Swedish Ringhals plants). This kind of treatment is called elevated Li/B chemistry. However, because of the risks involved in the application of higher lithium concentrations, this kind of treatment has been widely abandoned. 

It is very important to clarify the roles of endogenous plant hormones in the regulation of the life cycle of higher plants from the standpoint of not only plant physiology but agricultural application as well. 

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