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. 1987 Jan;83(1):131–136. doi: 10.1104/pp.83.1.131

Assimilate Unloading from Maize (Zea mays L.) Pedicel Tissues 1

I. Evidence for Regulation of Unloading by Cell Turgor

Gregory A Porter 1,2,2, Daniel P Knievel 1,2, Jack C Shannon 1,2
PMCID: PMC1056311  PMID: 16665188

Abstract

Sugar and 14C-assimilate release from the pedicel tissue of attached maize (Zea mays L.) kernels was studied following treatment with solute concentrations of up to 800 millimolal. Exposure and collection times ranged from 3 to 6 hours. Sugar and 14C-assimilate unloading and collection in agar traps was reduced by 25 and 43%, respectively, following exposure to 800 millimolal mannitol. Inhibition of unloading was not specific to mannitol, since similar concentrations of glucose, fructose, or equimolar glucose plus fructose resulted in comparable inhibition. Ethylene glycol, a rapidly permeating solute which should not greatly influence cell turgor, did not inhibit 14C-assimilate unloading. Based on these results, we suggest that inhibition of unloading by high concentrations of sugar or mannitol was due to reduced pedicel cell turgor. Changes in pedicel cell turgor may play a role in the regulation of assimilate transfer within the maize kernel.

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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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