Journal of Stress Physiology & Biochemistry, Vol. 6 No. 4
2010, pp. 90-107 ISSN 1997-0838
Original Text Copyright (cc) 2010 by Gallagher, Granger, Keser, Rossi, Pittmann,
Rowland, Burnham, Fuerst
ORIGINAL
ARTICLE
Data source : Google Scholar
QueryDate : 2016-12-24
Cites : 4 + 1
Shade and Drought Stress-Induced Changes in Phenolic Content
of Wild Oat (Avena fatua L.)
Seeds
Gallaghera,d Robert S., Kristen L. Grangera,
Lidewij H. Keserb, Jairus Rossia, Dennis Pittmannc
, Sebastian Rowlanda, Mark Burnhama, † and E.
Patrick Fuerstc
a Department of Crop and
Soil Sciences, The Pennsylvania State University, University Park,
Pennsylvania 16802 b Institute for Plant Sciences, Bern, Switzerland; c Department of Crop and Soil Sciences, Washington State
University, Pullman, Washington 99164 demail for corresponding author: rsg14@psu.edu
Received November 2, 2010
Plants develop under a wide range of maternal environments,
depending on the time of emergence, prevailing competition from other
plants, and presence or absence of other biotic or abiotic stress
factors. Stress factors, such as light limitation and drought, during
plant development typically reduces the reproductive allocation to
seeds, resulting in fewer and often smaller seeds. Such stress factors
may also influence seed quality traits associated with persistence in
the soil, such as seed dormancy and chemical defense. For this
research, we hypothesized that light limitation and drought during wild
oat (Avena fatua L.) seed
development would result in reduced allocation to seed phenolics and
other aliphatic organic acids previously identified in the seeds of
this species. Wild oat isolines (M73 and SH430) were grown in the
greenhouse under cyclic drought conditions (2005 only) or two levels of
shade (50 and 70%; 2005 and 2006) achieved with standard black shade
cloth. The soluble and cellular bound chemical constituents were
identified and quantified using gas chromatography - mass spectrometry.
The shade and drought stress treatments often significantly affected
the mass of the caryopsis and hull seed fractions, as well as the
phenolic content of these seed fractions, depending upon isoline, seed
fraction, phenolic fraction, and specific phenolics analyzed. Phenolic
content of the hull was reduced by the stress environments by up to
48%, whereas there was some evidence of an increase in the soluble
phenolic content of the caryopsis in response to the stress
environments. Ferulic and p-coumaric acids were the most abundant
phenolic acids in both soluble and bound fractions, and bound phenolics
comprised generally 95% or more of total phenolics. There was no
discernable evidence that the aliphatic organic content was affected by
the stress environments. Our results indicate that plant stress during
seed development can reduce both the physical and chemical defense in
seeds, which may result in seeds that are less persistent in the soil
seed bank and potentially less of a weed management concern.
key words: Seed chemistry, Secondary
compounds, Seed defense, Seed longe
