Journal Article

The influence of secondary senescence processes within the culm of a pseudoviviparous grass (<i>Poa alpina</i> var. <i>vivipara</i> L.) on the supply of water to propagules

S. Pierce, C.M. Stirling and R. Baxter

in Journal of Experimental Botany

Volume 51, issue 347, pages 1067-1075
Published in print June 2000 | ISSN: 0022-0957
Published online June 2000 | e-ISSN: 1460-2431 | DOI: http://dx.doi.org/10.1093/jexbot/51.347.1067
The influence of secondary senescence processes within the culm of a pseudoviviparous grass (Poa alpina var. vivipara L.) on the supply of water to propagules

More Like This

Show all results sharing this subject:

  • Plant Sciences and Forestry

GO

Show Summary Details

Preview

An anatomical investigation of the culm of pseudoviviparous alpine meadow grass (Poa alpina var. vivipara L.) revealed that transpiration flow, as delimited by Lucifer Yellow tracer dye, was maintained despite advanced senescence (as evidenced by loss of chlorophyll and chloroplasts), with leafy spikelets driving transpiration flow. Transpiration flow was not hindered by cavitation or tylosis in older culms, the low frequencies of these senescence processes being bypassed via nodal plexi. Despite this, water content of plantlets declined over time and water stress became apparent, suggesting that water supply via the determinate culm was not sufficient for the increasing transpirational demand of indeterminate plantlets. The implications of declining water content on the biomechanical properties of the culm, and concomitant limitations on the pseudoviviparous reproductive strategy, are discussed. Nomenclature of grass follows Hubbard.

Keywords: Poa alpina; senescence; tylosis; pseudovivipary; water.

Journal Article.  5080 words.  Illustrated.

Subjects: Plant Sciences and Forestry

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.