Soybean leaves

Moftah, A.E. Michel, B.E. (1987). The effect of sodium chloride on solute potential and proline accumulation in soybean leaves. Plant Physiology, 83, 238-43. 

Next, we attempted to deal with translocation of foliar-applied TCDD. Labeled dioxins were applied to the center leaflet of the first trifoliate leaf of 3-week-old soybean plants and the first leaf blade of 12-day-old oat plants. All compounds were applied in an aqueous surfactant solution (Tween 80) to enhance leaf adsorption and to keep the water insoluble dioxins in solution. Plants were harvested 2, 7, 14, and 21 days after treatment, dissected into treated and untreated parts, and analyzed separately. Neither dioxin nor chlorophenol was translocated from the treated leaf. A rapid loss of the dichlorodioxin and dichlorophenol occurred from the leaf surface. This loss may have resulted from volatilization. Very little TCDD was lost from soybean leaves while a gradual loss (38% in 21 days) did occur from oat leaves. 

Einhellig and Rasmussen (17) reported that In addition to ferulic and p-coumaric acids, vanillic acid reduced chlorophyll content of soybean leaves but did not affect chlorophyll In grain sorghum fSorghum bicolor (L.) Moench.]. It Is not known whether these reported mechanisms are primary or secondary events In the Inhibition of plant growth by allelochemlcals. 

Although LOX from soybean seed is the best characterized of plant LOXs, this enzyme is present in a wide variety of plant and animal tissues (Liavonchanka and Feussner, 2006). The enzyme occurs in a variety of isoenzymes, which often vary in their optimum pH and in product and substrate specificity. Given the occurrence of multiple LOX isoenzymes in soybean leaves and the proposed roles of these enzymes in the plant metabolism, it is possible that individual isoenzymes play specific functions (Feussner and Wasternack 2002). The molecular structure of soybean LOX is the most reported, and four isoenzymes have been isolated (Baysal and Demirdoven 2007). Soy isoenzyme 1 produces 9- and 13-hydroperoxides (1 9) when the enzyme acts on free PUFA at pH 9.0, its optimum pH (Lopez-Nicolas and others 1999). Soy isoenzyme 2 acts on triglycerides as well as free PUFA leading to 9- and 13-hydroperoxide... 

Tingey, D. T., R. C. Fites, and C. Wickliff. Activity changes in selected enzymes from soybean leaves following ozone exposure. Physiol. Plant. 33 316 320, 1975. 

When soybean leaves and pine needles were exposed to ozone, there was an initial decrease in the levels of soluble sugars followed by a subsequent increase. Ozone exposure also caused a decrease in the activity of the glycolytic pathway and the decrease in the activity was reflected in a lowered rate of nitrate reduction. Amino acids and protein also accumulated in soybean leaves following exposure. Ozone increased the activities of enzymes involved in phenol metabolism (phenylalanine ammonia lyase and polyphenoloxidase). There was also an increase in the levels of total phenols. Leachates from fescue leaves exposed to ozone inhibited nodulation. 

Fietire 1. Effects of a single ozone exposure on the levels reducing sugars in soybean leaves (3). Each mean is based on four observations. 

In plant leaves, nitrate reduction requires NADH produced by glycolytic activity (13), The ozone-induced depression of glycolytic metabolism in soybean leaves was also reflected in a depressed rate of nitrate reduction ( ), A single ozone exposure depressed the vivo nitrate reductase (NR) activity about 60% (Table III), To determine if ozone affected the NR protein directly, the in vitro NR activity was determined in leaf extracts from plants exposed to 0 and 980 pg/m ozone. 

In soybean leaves exposed to a single acute ozone dose (0, 490 or 980 yg/m3 ozone for 2 hr) the amino acid level was depressed immediately following exposure (Fig, 4A) ( ), This depression of amino acids was similar to that observed in levels of reducing sugars immediately following exposure and probably resulted from a depression in photosynthesis. Within 24 hr after exposure, the amino acid level in plants exposed to 490 yg/m had returned to the control level. However, in plants exposed to 980 yg/m3, the amino acid level increased above that of the control. Concurrent with the rise in free amino acids was an increase in protein level in exposed foliage (Fig, 4B), The increase in amino acids following an ozone exposure has been reported by other workers (, 14, 15) however, in these cases, the rise in free amino acid level was associated with a decline in... 

Figure 3. Ozone alteration of dehydrogenases active in sugar oxidation in soybean leaves. Each mean is based on eight observations.

Table III. Effects of Ozone on Nitrate Reduction in Soybean Leaves ...

Figure 1-1. Kent soybean leaves a. No ozone but cleared in 95% ethanol, b-g. Treated with ozone 10 pphm 6 hr, removed from plants 0,1, 2, 4, 6, or 24 hrs after treatment and cleared, h. Ozone injury 24 hrs after treatment but not cleared.

Estimate the Kihio values (Eq. 10-4) of the two compounds partitioning to the soybean leaves and roots and compare these values with the experimentally determined BAFt values given above. How important are materials contributing to the plant biomass other than the lipids (i.e., proteins, polysaccharides, water) with respect to the accumulation of the two compounds in soybean Use Table 10.2 and Appendix C for solving this problem. 

RL Glass. Semipreparative high performance liquid chromatographic separation of phosphatidylcholine molecular species from soybean leaves. J Liq Chrom 14 339 -349, 1991. 

Streit, L., Martin, B.A. Harper, J.E. (1987). A method for the separation and purification of the three forms of nitrate reductase present in wild-type soybean leaves. Plant Physiology 84, 654-7. 

Branjeon, J., Hirel, B. Forchioni, A. (1988). Immunogold localization of glutamine synthetase in soybean leaves, roots and nodules. Protoplasma 151, 88-97. 

Zhuang, H., Hamilton-Kemp, T.R., Andersen, R.A., and Hildebrand, D.F. 1992. Developmental change in C6-aldehyde formation by soybean leaves. Plant Physiol. 100, 80-87. 

The metribuzin metabolite DK is deaminated, conjugated, and rapidly bound to insoluble fractions in soybean, as shown in Figure 7.17. Frear et al. (1985) hydroponically treated excised soybean leaves with 14C-DK for 48h. Only 16% of the total radioactive residues were organosoluble with a 3 1 ratio of DK and DADK. The water-soluble fraction was mainly A-malonyl DK, amounting to 17% of the residue. The remainder of the residues was nonextractable. iV-malonated DK was detected as a minor metabolite in this study. 

Klepper, L. 1991. NO evolution by soybean leaves treated with salicylic acid and selected derivatives. Pest. Biochem. Physiol. 39, 43-48... 

Drossopoulos, J.B., Bouranis, D.L., and Bairaktari, B.D., Patterns of mineral nutrient fluctuations in soybean leaves in relation to their position, J. Plant Nutr., 17, 1017-1035, 1994. 

Vascular Anatomy. One aspect of the translocation system that is often overlooked is the influence of the structural features of the plant s vascular system on solute transport. For example, although much of what is known about phloem loading has been derived from a few dicotyledon leaves, all dicotyledon leaves are not similar. A notable example is the soybean leaf. Soybean leaves are specialized in that they have a unique cell type called the paraveinal mesophyll... 

Figure 11. HPLC chromatograms comparing organic extracts of glyphosate treated soybean leaves to extracts of non-treated leaves. Origins of the chromatograms are on the left. Rightmost peak from treated leaf extract is shikimate-3-biphosphate.

The quantity and quality of food in the diet on which insects are reared may affect their size and survival capacity. Variegated cutworm larvae fed peppermint leaves were more tolerant of the insecticides carbaryl, acephate, methomyl, and malathion than larvae fed snap bean leaves. Increased tolerance for carbaryl and methomyl was also observed in larvae of the alfalfa looper and cabbage looper when they were fed peppermint plants instead of their favored host plants alfalfa and broccoli. Furthermore, fall armyworm larvae fed corn leaves became less susceptible to the insecticides methomyl, acephate, methamido-phos, diazinon, trichlorfon, monocrotophos, permethrin, and cypermethrin than those fed soybean leaves. Although nutrition may play some role in these cases, it was found that enhanced insecticide tolerance caused by these host plants was mainly due to plant allelochemicals, which induced detoxification enzymes in the insects (Yu, 1986). 

Caldwell, C. R., Turano, F. J., and McMahon, M. B., 1998, Identification of two cytosolic ascorbate peroxidase cDNAs from soybean leaves and characterisation of their products by functional expression in E. coli, Planta 204 1200126. 

The relative order of efficiency of accumulation of the thpee radionuclides into edible tissues was Zn>Fe>Se. Most of the Zn transported to the above ground plant parts was accumulated by the seeds, however, much of the dose of each of the radionuclides remained in the roots and nutrient solution. The calculated percent of the applied dose taken up by soybean leaves is underestimated since some of the leaves abscised as the plants senesced and they were discarded. Zinc and iron have been classified as partially mobile in the phloem (8). Translocation of iron within plants is poor since new growth of plants require a continuous supply of iron via the xylem or from external applications ( ). Zinc deficiencies of plants can be corrected by applying ZnSO. in a dilute spray. However, iron deficiences of plants are usually difficult to correct which implies a lesser mobility within the plant. 

How to Attract Soybeans, pigweed, and goldenrod are favored sites for the bugs to lay eggs. Interplant crops with soybeans leave weedy plants in borders. 

Tingey, D.T., R.C. Fites, and C. Wickliff. 1975. Activity changes in selected enzymes from soybean leaves following ozone exposure. Physiol. Plant 33 316-320. Wellburn, A.R., O. Majernik, and F.A.M. Wellburn. 1972. Effects of S02 and NOz polluted air upon the ultrastructure of chloroplasts. Environ. Pollut. 3 37-49. Zeevaart, A.J. 1976. Some effects of fumigating plants for short periods with N02. Environ. Pollut. 11 97-108. 

For example, in the leaves of cotton, highly tolerant to diuron, S0% of the diuron taken up was present in the form of nontoxic 3-(3,4-dichlorophenyl)urea, while no unchanged diuron was found. On the other hand, in the leaves of soybean, sensitive to diuron, 48% of the diuron taken up was found under identical experimental conditions in the form of phytotoxic 3-(3,4-dichlorophenyl)-l-methylurea and 9% as unchanged diuron (Van Oorschot, 196S Smith and Sheets, 1967 Swanson and Swanson 1968). Field experiments gave similar results. In cotton leaves the main metabolite was 3-(4-chlorophenyl)urea, in soybean leaves 3-(4-chlorophenyl)-l-methylurea. Metabolism proceeded in cotton leaves as far as 4-chloroaniline, while this final metabolite could not be detected in soybean. 

Many diseases and insects through premature senescence or plant death can indirectly affect soybean seed quality. Soybean rust, caused by Phakopsora pachyrhizi, attacks soybean leaves primarily, but not seed, leading to defoliation and early senescence. Yield losses are due to a reduction in seed number and seed size. Seed size losses of 12 to 20% can occur (Arias et al., 2005 Dupleich et al., 2005). 

Figure 6.2. Molybdenum concentrations in tobacco and soybean leaves. Method 1 is by a spectrophotometric procedure, and method 2 by the KI-H2O2 procedure. (Reprinted from Eivazi et al., 1982, with permission of Marcel Dekker, Inc.)...

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