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. 1990 Feb;92(2):310–315. doi: 10.1104/pp.92.2.310

Inducing Gravitropic Curvature of Primary Roots of Zea mays cv Ageotropic 1

Randy Moore 1,2, Michael L Evans 1,2, W Mark Fondren 1,2
PMCID: PMC1062291  PMID: 11537997

Abstract

Primary roots of the mutant `Ageotropic' cultivar of Zea mays are nonresponsive to gravity. Their root caps secrete little or no mucilage and touch the root only at the extreme apex. A gap separates the cap and root at the periphery of the cap. Applying mucilage from normal roots or substances with a consistency similar to that of mucilage to tips of mutant roots causes these roots to become strongly graviresponsive. Gravicurvature stops when these substances are removed. Caps of some mutants secrete small amounts of mucilage and are graviresponsive. These results indicate that (a) the lack of graviresponsiveness in the mutant results from disrupting the transport pathway between the cap and root, (b) movement of the growth-modifying signal from the cap to the root occurs via an apoplastic pathway, and (c) mucilage is necessary for normal communication between the root cap and root in Zea mays cv Ageotropic.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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