Plant cuticular material

The aliphatic components of SOM, derived from various sources, tend to persist in soil (Almendros et al. 1998 Lichtfouse et al. 1998a Lichtfouse et al. 1998b Mosle et al. 1999 Poirier et al. 2000). The principal source of aliphatic materials in soil is plant cuticular materials, especially cutin, an insoluble polyester of cross-linked hydroxy-fatty acids and hydroxy epoxy-fatty acids (Kolattukudy 2001). Some plant cuticles also contain an acid and base hydrolysis-resistant biopolymer, comprised of aliphatic chains attached to aromatic cores known as cutan (Tegelaar et al. 1989 McKinney et al. 1996 Chefetz 2003 Sachleben et al. 2004). 

Chen B, Johnson E, Chefetz B, Zhu L, Xing B (2005) Sorption of polar and nonpolar aromatic organic contaminants by plant cuticular materials role of polarity and accessibility. Environ Sci Technol 39 6138-6146... 

Pyrolysis of humic materials and of its components has been done for numerous purposes. One such purpose is structure elucidation. Also, as humic substances have more components that are of different origin (cellulose, lignin, plant cuticular materials), pyrolysis has been used to infer the source of each humic component and to assess its resistance to degradation in time [5]. Also, characterization of different types of soils has been done using pyrolysis studies [6,7]. 

Sorption to soil solids and plant cuticular material represents an important process influencing the chemodynamic behavior of insecticides, including their transport in surface runoff Sorption phenomena affect the volatilization, hydrolysis, photolysis and microbial transformation of organophosphorus insecticides. Furthermore, species sorbed to soil particles are transported by erosion processes rather than as solutes in the water phase. Sorption to foliar surfaces reduces the amount of pesticide mobilized by washoff. 

While the occurrence of most processes affecting organophosphorus insecticide concentrations in surface runoff are well documented, many are relatively poorly understood on a mechanistic level. Key processes requiring further study include sorption to plant and soil surfaces, and transfer from soil water into overland flow. Sorption to foliar surfaces determines the amount of applied insecticide available for washoff onto the soil surface or into surface runoff The kinetics of desorption from plant cuticular materials and the effect of adjuvants on foliar sorption processes need additional research. 

Some organic polymers are rather unique and are not common in nature. An example is the polymer from the leaf cuticle of some plants such as Agave americana [1]. This cuticular material contains a macromolecular material that contains polysaccharides and a polymethylene moiety in the estimated ratio 60/40 by weight. Pyrolysis products of an isolated macromolecular fraction of the cuticular material has been proven to have the following structure ... 

From the results it is clear that no residues were found up to the sensitivity limit of the analytical methods used. Furthermore untreated leaves were found to contain practically no radioactive material. It can be concluded that diflubenzuron after application on plants is very persistent and has no systemic properties. In other studies it was found that diflubenzuron does not permeate through the cuticular barrier into the leaves of broad bean. These studies on the fate of diflubenzuron on and in plants will be published more extensively elsewhere ( J ) Essentially the same results were obtained by Still in a study on the metabolic fate of diflubenzuron on cotton plants ( 2). In addition to metabolism, other factors might influence the fate of diflubenzuron on plants, i.e. washing off and photochemical degradation. Ruzo et al. (jQ) and Metcalf et al. (30)... 

The relatively minor hydrocarbon liquids that are generated by most humic coals are characteristic of higher plant material. Coal-sourced oils are generally dominated by cuticular-wax derived fi-alkanes, although benzene, naphthalene and phenanthrene and their alkyl derivatives are usually important. Small amounts of larger aromatic hydrocarbons formed from... 

Bargel, H., Koch, K., German, Z., and Neinhuis, C. (2006). Structure function relationship of the plant cuticle and cuticular waxes—A smart materials, FunctPIant iol, 33(10), 893-910. 

A. Plant Systems. A system of null potential voltammetry was developed for investigating the effects of biocides and surfactants on the transport properties of leaf epidermal membranes. These membranes were obtained by a procedure which was found suitable for a wide variety of plant species. A residual translucent membrane composed of epidermal cells and the associated cuticular surface was exposed by gently rubbing the abaxial surface of the leaf with a moistened cotton-tipped applicator until all of the green material was removed. In these studies advantage was taken of the... 

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