ISSN 10214437, Russian Journal of Plant Physiology, 2014, Vol. 61, No. 4, pp. 460–466. © Pleiades Publishing, Ltd., 2014.
Drought is an important environmental stress that
adversely affects growth and causes a reduction in the
growth rate, stem elongation, and leaf expansion [1–
3]. Drought stress usually causes a decrease in crop
production. It inhibits the photosynthesis, causes
changes in the chlorophyll (Chl) content, and dam
ages the photosynthetic apparatus . Gong et al. 
reported that drought induced changes in the oxidative
damage to wheat photosynthetic pigments, proteins,
In many areas, plants face soil oxygen deficiency,
another environmental constraint. In flooded soil, dif
fusion of gases through soil pores is strongly inhibited
by excessive water content. For most crops, excess
water is a major constraint to productivity in many
regions and situations . Milroy et al.  reported
that waterlogging treatment reduced the concentra
tion of the major nutrients and a number of micronu
trients in cotton plants.
This text was submitted by the authors in English.
The role of silicon in plant metabolism has
received increasing attention . It has a number of
beneficial effects on growth under biotic and abiotic
stresses [1, 8].
With respect to the role of silicon to waterlogging
stress, relevant works are limited. In the present work,
it seems interesting to focus on the physiological
behavior underlying maize plant responses to exoge
nous silicon application during water stress or anoxia.
Accordingly, we have investigated the effects of shoot
and root silicon supplementation on growth and some
metabolic aspects in maize plants exposed to soil water
limitation and oxygen deprivation.
MATERIALS AND METHODS
Plant material and experimental conditions.
L., cv Fard 4) plants were grown in plastic
pots containing 4 kg of air dry soil (sand/clay, 1 : 2) in
the Experimental outdoor greenhouse at of the Fac
ulty of Science, Assiut University (Egypt) under natu
ral field conditions of temperature, humidity, light,
and day/night regime. The plants (4 per pot) were
watered with full nutrient solution prepared according
Down and Hellmers . Plants were grown for 15 days
in the soil, the water content of which was maintained
at field capacity. One set of the plants was then sub
Effects of Silicon on
Plants Exposed to Water
and Oxygen Deficiency
S. A. Sayed and M. A. A. Gadallah
Botany Department, Faculty of Science, Assiut University, Assiut, Egypt;
fax: 002088234278; email: firstname.lastname@example.org
Received July 11, 2013
—Effects of shoot and root supplementation with silicon on the response of
L. plants to
matric water potential (
) and oxygen deficiency (waterlogging) stresses were studied. The soil water limi
) and oxygen deprivation significantly reduced shoot dry weight, chlorophyll (Chl) content, ascor
bic acid content, as well as leaf relative water content. Both soil drying and waterlogging caused a significant
increase in the leaf membrane injury by heat (51
C) and dehydration (40% PEG) stresses. The levels of lipid
peroxidation (POL) and hydrogen peroxide (H
) content were increased by excess soil drying and oxygen
deficiency. Supplementary silicon at 1.0 mM significantly increased Chl content and improved water status.
Concentrations of H
, MDA, and proline and leaf membrane injury were significantly reduced by Si appli
cation. The reverse helds true for ascorbic acid. The results of this study indicate that application of silicon
might improve growth attributes, effectively mitigate the adverse effect of drought and waterlogging, and
increase tolerance of maize plants. The siliconinduced improvement of drought and anoxia tolerance was
associated with the increase in oxidative defense abilities.
Keywords: Zea mays
, anoxia, antioxidant, drought, flooding, matric potential, soluble sugars
: AscA—ascorbic acid; Chl—chlorophyll; POL—
peroxidation of lipids,
—matric potential; RWC—relative
water content; SS—soluble sugars; WL—waterlogging.