INTRODUCTION . . . . . . . .... . . . . . . ... . . . . . .. . . . . . . . ........ .. . . . . . . . . ..... . . . . . . . . . . . . . . .. . . . . . . . . . . . . 439 History of Salicylates .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 439 General Properties of Salicylic Acid. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 441 Salicylic Acid Levels in Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 442 EFFECTS OF EXOGENOUS SALICYLIC A CID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 442 Salicylic Acid and Flowering . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 442 Allelopathic Properties of Salicylic Acid : Effect on Membranes and Ion Uptake. .. . 444 Other Effects of Exogenously Applied Salicylic Acid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 445 SALICYLIC ACID A ND H EAT PRODU CTION IN PLANTS . . . . . . . . . . . . . . . . . . . .. . . . . . . . . 445 Thermogenic Plants and Search for Calorigen. . . . . . . .. . . . . . . . . . ...... . . . . 445 Salicylic Acid : A Natural Inducer of Thermogenesis in Arum Lilies . . . . . . . . . .... . . . . . . 446 SALICYLIC ACID A ND D IS EAS E RES ISTANCE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 447 Disease Resistance in Plants: Effects of Salicylic Acid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 447 Salicylic Acid : A Likely Signal for Disease Resistance in Plants. .... . . . . . . . . . . . . . . . .. 450 SALICYLIC ACID BIOSYNTHES IS IN PLANTS . .. . . ... .. . . . . . . . . . . . . ...... . . . . . . . . . . . . . . .. 451 Biosynthetic Pathway. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 451 Biosynthetic Enzymes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 453 SALICYLIC ACID M ETABOLISM . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 454 MI CRO BIAL PRODU CT IO N OF SALICYLIC ACID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 454 CO NCLUDING REMARKS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Role of Salicylic Acid in Plants

Polyphenol oxidases in plants

Effect of exogenous salicylic acid under changing environment: a review

The information available on the biological activity of hydrogen sulfide has been examined for present status of critical results pertaining to the toxicity of hydrogen sulfide. This review of the literature is intended as an evaluative report rather than an annotated bibliography of all the source material examined on hydrogen sulfide. The information was selected as it might relate to potential toxic effects of hydrogen sulfide to man and summarized, noting information gaps that may require further investigation. Several recommendations are listed for possible consideration for either toxicological research or additional short- and long-term tests. Two bibliographies have been provided to assist in locating references considered in this report: (1) literature examined but not cited and (2) reference citations. The majority of the references in the first bibliography were considered peripheral information and less appropriate for inclusion in this report.

A Critical Review of the Literature on Hydrogen Sulfide Toxicity

The chemical structures of the primary cell walls of the grasses and their progenitors differ from those of all other flowering plant species. They vary in the complex glycans that interlace and cross-link the cellulose microfibrils to form a strong framework, in the nature of the gel matrix surrounding this framework, and in the types of aromatic substances and structural proteins that covalently cross-link the primary and secondary walls and lock cells into shape. This review focuses on the chemistry of the unique polysaccharides, aromatic substances, and proteins of the grasses and how these structural elements are synthesized and assembled into dynamic and functional cell walls. Despite wide differences in wall composition, the developmental physiology of grasses is similar to that of all flowering plants. Grass cells respond similarly to environmental cues and growth regulators, exhibit the same alterations in physical properties of the wall to allow cell growth, and possess similar patterns of wall biogenesis during the development of specific cell and tissue types. Possible unifying mechanisms of growth are suggested to explain how grasses perform the same wall functions as other plants but with different constituents and architecture.

Eric E. Conn

Papers

The metabolism of aromatic compounds in higher plants. IV. Purification and properties of the phenylalanine deaminase of Hordeum vulgare.

Cyanide Metabolism in Higher Plants III. THE BIOSYNTHESIS OF β-CYANOALANINE

Cyanide metabolism in higher plants. V. The formation of asparagine from -cyanoalanine.

The cinnamic acid 4-hydraxylase of pea seedlings☆

The 4-Hydroxylation of Cinnamic Acid by Sorghum Microsomes and the Requirement for Cytochrome P-450