This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Frick, H. Articles by Hodges, T. K. Search for Related Content PubMed PubMed Citation Articles by Frick, H. Articles by Hodges, T. K. Agricola Articles by Frick, H. Articles by Hodges, T. K.

Articles

Influence of Helminthosporium maydis, Race T, Toxin on Potassium Uptake in Maize Roots

II. Sensitivity of Development of the Augmented Uptake Potential to Toxin and Inhibitors of Protein Synthesis ¹

^a Departments of Agronomy, and Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907

Basal K⁺ uptake in the root midzone region (cm 2 + 3 + 4) of N and T cytoplasmic versions of each of four maize inbreds was equally sensitive to the toxin(s) of Helminthosporium maydis, race T. Basal K⁺ uptake in the root apex (0-1 cm) and augmented K⁺ uptake in the root midzone were more toxin-sensitive in inbreds W64A(T) and Mo17(T) than in inbreds W64A(N) and Mo17(N). This differential response of N and T cytoplasms to toxins was not found for corresponding cytoplasms of inbreds WF9 and B37.

Development of the augmented K⁺ uptake rate in midzone segments of W64A(T) was blocked by a toxin concentration which did not affect augmentation development in W64A(N). Augmentation development was more toxin-sensitive in T than in N cytoplasmic versions of all inbreds tested. Fertility-restoring nuclear loci decreased but did not eliminate the toxin sensitivity of augmentation developments as observed in root midzones of inbred A619(T). Chloramphenicol-and/or cycloheximide-sensitive protein synthesis was required for augmentation development, but not for expression of either basal or augmented K⁺ uptake.

³ Present address: Department of Plant Science, University of Delaware, Newark, Delaware 19711.

⁴ Department of Botany and Plant Pathology.

¹ Supported in part by the United States Department of Agriculture, Cooperative States Research Service, Grant 1771505, and by National Science Foundation Grant GB-31052X. This report is Journal Paper No. 6215 of the Purdue Agriculture Experiment Station.