Foliage analysis

For studies involving test substance application to soil, there may be a requirement for more soil information than for studies where applications are made to foliage of established crops. The study protocol should describe any specific requirements relative to soil type selection and how to confirm the soil characteristics for the study. Most studies simply require that the soil be identified by its name (e.g., Keystone silt loam) and composition (e.g., percent sand, silt, and clay). This information can typically be acquired from farm records, a soil survey of the local area, or a typical soil analysis by a local soil analysis laboratory. In some instances, a GLP compliant soil analysis must be completed. The study protocol must clearly define what is needed and how it is to be obtained. Unless specified in the protocol, non-GLP sources are adequate to identify the soil and its characteristics. The source of the soil information should be identified in the field trial record. 

The foliage of the food plants was ground and the pigments were extracted into warm methanol and saponified in 4% sodium hydroxide. The carotenoids were extracted into dichloromethane, dried, and redissolved in ethanol prior to an analysis by HPLC. 

Results obtained for the application of HPLC—APCI—MS to the quantification of M2D—C3—O—(EO ) —CH3 recoveries from Chenopo-dium album plant foliage are shown in Table 2.8.5, as compared with HPLC-LSD analysis [29], The improvements in the sensitivity and reproducibility were obtained with the use of HPLC—APCI—MS as the analytical method and the HPLC—APCI—MS method also enabled detection of the n = 3 M2D-C3-0-(E0) -CH3 molecule. 

Soto-Hernandez, M. and Jackson, A. H. 1993. Studies of alkaloids in foliage of Erythrinia berteroana and E. poeppigiana detection of 3-erythroidine in goats milk. Phytochemical Analysis, 4 97-99. 

Both the time of analysis and experimental design may affect the results. An explanation for the increase in adenylates under the conditions of our experiment is still needed. Since both ATP alone and total adenylate concentrations have increased, it does not appear that a shift in phosphorylation can account for the increases. The decrease in photosynthesis and increase in adenylates occur during the same time period and both factors return to normal after 21 hr. From previous research we know that the photosynthetic levels of ozonated pinto bean foliage decrease immediately after ozone exposure even when symptoms do not develop ( ). This does not hold true for the adenylate or respiration responses. Therefore, it appears that the ozone-initiated increase in adenylates is not correlated directly to the photosynthetic response. The increase in respiration persists when adenylate content and photosynthetic rates have returned to normal. Impaired mitochondrial function appears to be a secondary response more closely related to symptom development. 

Natural budworm densities were determined by sampling 6 sprays, each 40 cm long, In the same quarter of the tree used to collect tissue for chemical analysis and to collect defoliation data. Densities were expressed as the average number of budworm larvae per 100 buds per tree. A visual estimate of the amount of defoliation eilso was made In the same area of the crown where the densities and needle tissue were collected. Since budworm may disperse from heavily defoliated trees, (Greenback, 1963) budworm densities from each tree were weighted by the level of defoliation that each tree sustained. This resulted In an Infestation Intensity measurement (dependent variable) which was subjected to multiple stepwise correlation analysis using various foliage quality and physical tree parameters as the Independent variables. Thirty-one parameters were used as Independent variables In this analysis. 

V-930. The method for terpene analysis followed Redak (1982) with only minor modifications In column loading time. Dr. D. F. Zlnkel (Forest Products Laboratory, USDA, Madison, Wisconsin) kindly analyzed the young foliage for resin acids. The resin acids were not detected and no detailed analysis of the needles for these chemicals was done In any of our studies. 

A total of 34 variables were used In the multiple stepwise correlation analysis. Twenty-three were used to determine foliage quality, while 11 variables were used to define the physical and phenologlcal attributes of the sample trees. The dependent variables used were average adult female budworm dry weight and average adult male budworm dry weight for each tree. Details are found In Redak (15). 

The evenness measurement, calculated from the Shannon-Wiener formula, suggests that trees which have an uneven distribution of terpenes are more resistant to the budworm. It is likely that this Imbalance In the terpene distribution Is represented by the specific terpenes (acetate fraction, myrcene, and the unidentified terpene) that were found to be important In the analysis. The analysis also Indicated that the polyphenol and protein complexlng capacity of the extracts from the foliage... 

Selected methods for the analysis of ethylbenzene in various matrices are given in Table 1. Ethylbenzene can be determined in biological material (blood, subcutaneous fat, plant foliage, fish samples) using head-space gas chromatography (GC), GC with mass spectrometry, and GC with flame ionization detection (WHO, 1996a). 

GR Pieper. Residues analysis of carbaryl on forest foliage and stream water using HPLC. Bull Environ Contain Toxicol 22 167-171, 1979. 

The safe levels established for parathion + paraoxon, azinphosmethyl + azinphosmethyl oxon and methidathion + methi-dation oxon on foliage have absorbance values determined by the rapid field method (4 ) equal to those given in Table III. Absorbance values greater than those listed in Table III signal an unsafe working condition. Field testing can also be conducted by standard gas chromatographic analysis of the leaf disk samples by state-approved laboratories. 

Table 2.15. Interception by foliage of particulate activity deposited in rain (analysis of results of Hoffman et al., 1989)...

The insecticide aminocarb has also been used extensively in eastern Canada on budworm control operations. Fenitrothion has been applied as a water emulsion (New Brunswick) and an oil solution (Quebec), but aminocarb because of its formulation characteristics, has been only applied operationally as an oil solution. Analysis of spruce foliage (7) showed aminocarb had a half life of 5 to 6 days with complete disappearance by 64 days post spray. Subsequent work (8) confirmed the short half life of aminocarb on coniferous foliage (3.2 to 6.9 days), and showed that the half life was dependant on the initial concentration of the insecticide. The material was found to be highly labile and dissipated rapidly and the authors made the statement that with these characteristics... 

The insecticide acephate, applied as a water spray has a very short life in terns of biological activity and for this, as well as economic reasons, it is not used on large scale operations in Canada (12). Residue analysis of acephate foliar deposits (13) showed that more than half of the insecticide was lost within one day of spraying, and that by 32 days post spray, the amount of insecticide had decreased to less than 0.01 ppm (the detection limit for 20 gm of substrate). The metabolite of acephate known as Ortho 9006 (0,S-dimethyl phosphoramidothioate) was also assessed in this study but was found to be present only in very small amounts. At 2 hours post spray the average acephate concentration on spruce foliage was 55.15 ppm, and the average concentration of the Ortho 9006 was 0.12 ppm. There was no increase with time in the amount of the metabolite. The rapid... 

The same 60% methanol Sep-Pak fraction from the mimosa foliage extract was fractionated into 10 subfractions by HPLC (a different HPLC was used from the Fig. 4 results) and collected for subsequent analysis (see Fig. 6). In analyzing the ORAC value of these sub-fractions, it was found that the sixth sub-fraction contained nearly 90% of the total ORAC value (see Table 4). Initial HPLC and LC/MS tests on this sixth subfraction indicated the presence of a single peak giving strong ions at m/z 303 and 487 (see Fig. 7 A, 7B). The m/z 303 ion in this component was subsequently confirmed as protonated quercetin (see Fig. 8 for the structure of querce-... 

Fig. 6. Second HPLC analysis of mimosa foliage extract, fractionated with 60% methanol in Sep-Pak column.

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