Initial interaction with plants

Fellows RJ, Harvey SD, and Cataldo DA, Evaluation of the Metabolic Fate of Munitions Material (TNT RDX) in Plant Systems and Initial Assessment of Material Interaction with Plant Genetic Material, Validation of the Metabolic Fate of Munitions Material (TNT RDX) in Mature Crops, PNL-10825, prepared for the U.S. Army Biomedical Research and Development Laboratory, Fort Detrick, Frederick, MD, 1995. 

The components in a simple penetration experiment consist of a surfactant, water-soluble herbicide, and water. Since the surfactant is at a concentration of 0.5 to 1%, it interacts with water and forms micelles. Since micelles are formed, these could solubilize some of the herbicide inside the micelle. Now we have five components, (1) water, (2) surfactant monomer, (3) surfactant micelle, (4) micelle with solubilized herbicide, and (5) an herbicide in anhydrous or hydrated form which all come in contact with the plant. Which one or more of these components has the greatest effect on the plant Before a thorough understanding of this phenomenon can be achieved, the interaction of each of these components with a plant must be investigated separately, and perhaps the plant is too complex for initial study. Perhaps a homogeneous semipermeable membrane could be used instead. 

Phytoalexins are an Important component of the plant disease defense reaction called the hypersensitive response. Successful pathogens have evolved methods for dealing with plant phytoalexins. Including suppressors of their production, detoxification of the phytoalexins and In some cases avoiding elaboration of substances, called elicitors, that would otherwise Initiate the defense reaction. Elicitors obtained from pathogens are of considerable utility for study of various aspects of plant biology because of their interaction with the products of plant disease resistance genes. Substantial information has been obtained on how elicitors are perceived by plant cells and how they function, but much remains to be done. Finally, elicitors may prove of value for the economic production of exotic plant secondary metabolites and as specific herbicides. 

Effects of Free Moisture. Availability of free moisture after host inoculation with a foliar, epiphytic bioherbicide is critical to the initiation of the infection process. Experiments on free moisture (dew) interactions with other environmental parameters and the host-pathogen system are usually conducted in temperature-controlled dew chambers. This type chamber is constructed such that the plant radiates energy to a heat sink which is the temperature-controlled wall of the chamber. The humid air in the chamber is also temperature controlled, and dew forms on the plant... 

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