Growth regulators, determination

Electrophoretic and isotachoelectrophoretic techniques are gaining in popularity in soil analysis with applications to polyaromatic hydrocarbons, polychlorobiphenyls, tetrahydrothiophene and triazine herbicides, Paraquat and Diquat and growth regulators. Other lesser-used techniques include spectrophotometric methods (five determinants), spectrofluorimetric methods (two determinants), luminescence methods (one determinant), titration methods (one determinant), thin-layer chromatography (five applications), NHR spectroscopy (two applications) and enzymic immunoassays (one determinant). 

Stransky [255] investigated the determination in amounts down to lOpg kg-1 growth regulator Chlormequat in soil by capillary isotachophoresis. 

Virgin Islands. Extracts from macroalgae commonly harboring these dinoflagellates were tested in culture to determine their possible growth regulating properties. 

In this proceeding we have described the preparation of 32 plant growth regulators, three diterpenes, and an ongong effect to synthesize a structurally complex antitumor agent. Only time will determine whether any of these natural products and their derivatives become important pharmaceutical agents. 

The exact roles and interactions of hormones in the control of fruit development remain to be determined. The evidence suggests that all classes of plant-growth regulators probably play a part, and that their influence is perhaps effected by changes in their balance. 

RD Voyksner, T Cairns. Application of liquid chromatography-mass spectrometry to the determination of pesticides. In J Sherma, ed. Analytical methods for pesticides and plant growth regulators. New York Academic Press, 1989, pp 119-166. 

Our present efforts are being devoted to studying pea lipides in situ, in the hope of determining whether hormone activation by lipide substances is a natural method of growth regulation. Gas chromatography has already confirmed that our original active pea extract is a mixture of conventional fatty acid esters. 

Table 8.7. Determination of plant growth regulators and retardants (from author s own files)... 

A new, potent, persistent plant growth regulator and herbicide that should eventually have considerable agronomic value throughout the world is 4-amino-3,5,6-trichloropicolinic acid (4,5,6). Its biological activity is associated largely with its uptake from soils by plants. Therefore, it is important to determine and understand its interactions with soils and soil components and the effects of such interactions on the availability and leaching of the material in soils. Preliminary studies of this nature are described in this report. 

The complex activity and selectivity characteristics of substituted trifluoromethanesulfonanilide herbicides were not correctable with single molecular properties (see Table I and Ref. 5). We were particularly interested in determining whether the multiparameter Hansch equation, whose utility and apparent generality has already been substantiated in correlation studies on enzymatic systems (14, 15, 16, 17, 25), drugs and pharmaceuticals (18,19,20,23,24), pesticides (10,21), and plant growth regulators (22), could be used to provide meaningful structure—activity... 

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