Metabolism of Indoleacetic Acid in Rust Diseases. I. Factors Influencing Rates of Decarboxylation

Metabolism of Indoleacetic Acid in Rust Diseases. II. Metabolites of Carboxyl-labeled Indoleacetic Acid in Tissues

“…The Results Table I presents data illustrating a comparison of the distribution of radioactivity from IAA in healthy and rust-affected first leaf of wheat obtained 7 days after inoculation. At this stage, the rates of decarboxylation by healthy tissue are approximately linear with respect to time and increase on successive days (6). In diseased leaves, the rust had begun to sporulate and the rates of decarboxylation have dropped to rates comparable to those of young healthy tissue.…”

“…Since previous work on IAA metabolism in cereal rusts is supported by only one quantitative estimation of the amounts of IAA in deseased tissue (27), further analytical data are warranted. Additional studies of the role of IAA derivatives in the initial burst of decarboxylation activity described for the early stages of infection (6,27) are now in progress. Equally important are further investigations of their role in the light-induced stimulation or inhibition (6) of IAA decarboxylation reactions, especially as they relate to normal development of higher plants.…”

“…and Henn.) race 56 was described in the previous communication (6). In the present study, tissue was obtained 1 hour after the start of a light period.…”

“…In a previous paper (6), we reported different rates of decarboxylation of indoleacetic acid (IAA-C'400H) by healthy and rust-affected wheat leaves in the dark. As a result of infection the rate of decarboxylation first increased, but several days later, as the rust began to sporulate, declined to become much lower than that of healthy leaves.…”

Effect of 2,6‐dichloroisonicotinic acid, its formulation materials and benzothiadiazole on systemic resistance to alternaria leaf spot in cotton

“…Suspensions of each of the WP components were prepared in deionized water. Pure INA was insoluble in water and was dissolved in 0.2 mL of ethanol and quickly diluted with 400 mL of deionized water to make a 20‐μg g −1 solution, using a technique to dissolve a crystalline compound of similar molecular weight and structure that is water‐insoluble ( Daly & Deverall, 1963). A control solution of 0.2 mL ethanol in 400 mL deionized water was also used.…”