ArticlePDF Available
© 2005 Plant Management Network.
Accepted for publication 16 August 2005. Published 14 September 2005.
Silicon in the Life and Performance of Turfgrass
Lawrence E. Datnoff, Professor of Plant Pathology, University of Florida-
IFAS, Department of Plant Pathology, 1453 Fifield Hall, Gainesville 32611
Corresponding author: Lawrence E. Datnoff. ledatnoff@ifas.ufl.edu
Datnoff, L. E. 2005. Silicon in the life and performance of turfgrass. Online. Applied
Turfgrass Science doi:10.1094/ATS-2005-0914-01-RV.
Over the past few years there has been a growing interest in the element
silicon and its effects on the life and performance of plants. Many turfgrass
managers want more information regarding its role in plant function. This
article attempts to address that issue by first presenting general information
about silicon in soil, silicon in plants, and silicon effects on abiotic (i.e., heat
stress, drought stress, mineral toxicities, and wear tolerance) and biotic (plant
diseases and insects) stress. Then, the currently-known role of silicon in
turfgrass is explained along with mechanism(s) of silicon-mediated resistance to
plant diseases. Finally, an outlook section on the future for silicon in turfgrass
performance is presented.
Silicon in Soil
Silicon (Si) is the second most abundant mineral element in soil after oxygen
and comprises approximately 28% of the earth's crust (11,12). Despite the
abundance of Si in most mineral soils worldwide, Si deficiency can still occur
due to Si depletion from continuous planting of crops that demand high
amounts of this element, such as rice (11). Rice can uptake roughly 230 to 470 kg
of Si per ha and intensive cropping results in the removal of Si from the soil
solution at a rate faster than it can be replenished naturally (11,33). Silicon
deficiency occurs more often in highly-weathered, low-base-saturation, and low-
pH soils such as Oxisols and Ultisols which are used to cultivate upland rice in
A
sia, Africa, and Latin America (32).
Heavy rainfall in regions where these two types of soils occur can cause high
degrees of weathering, leaching, and desilification (33). Organic soils (Histosols)
are also deficient in plant-available Si because of the greater content of organic
matter (» 80%) and low content of minerals. Those Entisols having a high
content of quartz sand (SiO
2
) are also low in plant-available Si (6). Such Si-
deficient conditions may be prevalent on USGA-based quartz sand greens and
tees.
Soil solutions generally have a Si concentration of 3 to 17 mg of Si per liter
(19). This is considered low, but nevertheless it is 100 times greater than
phosphorus in most soil solutions.
Silicon in Plants
Many plants are able to uptake Si. Plants absorb Si from the soil solution in
the form of monosilicic acid, Si(OH)
4
, which is carried by the transpiration
stream and deposited in plant tissues as amorphous silica gel, SiO
2
nH
2
O, also
known as opal (33,35). Depending upon the species, the content of Si
accumulated in the biomass can range from 1% to greater than 10% by weight
(11,12). Plant species are considered Si accumulators when the concentration of
Si (dry weight basis) is greater than 1% (13). Relative to monocots, dicots such as
tomato and soybean are considered poor accumulators of Si with values less that
0.1% of Si in their biomass. Terrestrial grasses such as wheat, oat, rye, barley,
sorghum, corn, sugarcane, and turfgrass contain about 1% of Si in their biomass,
while aquatic grasses have Si content up to 5% (12,13,20,25). On a weight basis,
Si is taken up at levels equal to or greater than essential nutrients such as
nitrogen and potassium in plant species belonging to the families Poaceae,
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Equisetaceae, and Cyperaceae (33). Although Si has not been considered an
essential element for crop plants for lack of supportive data, species such as
E
quisetum and some diatomaceaes cannot survive without an adequate level of
Si in their environment (12,13). Currently, 21 plant families have been identified
as being Si accumulators (26).
Silicon Effects on Abiotic and Biotic Stress
The beneficial effects of Si, direct or indirect, to plants under abiotic and/or
b
iotic stress have been reported to occur in a wide variety of crops such as rice
(Oryza sativa), oat (Avena sativa), barley (Hordeum vulgare), wheat (Triticum
aestivum), cucumber (Cucumis sativus), sugarcane (Saccharum officinarum),
ornamentals (such as paper daisy, Banksia gardneri), and turfgrass (such as St.
A
ugustinegrass, Stenotaphrum secundatum) (10,12,13). Leaves, stems, and
culms of plants grown in the presence of Si show an erect growth, especially for
rice. This suggests that the distribution of light within the canopy is greatly
improved (11,12,33). Silicon increases rice resistance to lodging and drought,
and dry matter accumulation in cucumber and rice (1,12,22). Silicon can
positively affect the activity of some enzymes involved in the photosynthesis in
rice and turfgrass (33,34) as well as reduce rice leaf senescence (21). Silicon can
lower the electrolyte leakage of rice leaves, promoting greater photosynthetic
activity in plants grown under water deficit or heat stress (2). Silicon increases
the oxidation power of rice roots, decreases injury caused by climate stress such
as typhoons and cool summer damage in rice, alleviate frost damage in
sugarcane and other plants, and favors supercooling of palm leaves (17,33).
Silicon reduces the availability of toxic elements such as manganese (Mn), iron
(Fe), and aluminum (Al) to roots of plants such as rice and sugarcane and
increases rice and barley resistance to salt stress (23,33). Moreover, the most
significant effect of Si to plants, besides improving their fitness in nature and
increasing plant productivity, is the suppression of insect feeding and plant
diseases (3,6,8,33).
Role of Silicon in Turfgrass
Fertilization with Si has shown positive effects in alleviating abiotic stress as
well as improving plant growth and development in several turfgrass species.
Since Si improves leaf and stem strength through deposition in the cuticle and
b
y maintaining cell wall polysaccharide and lignin polymers (19,35), the
possibility exists that Si could improve wear tolerance. Saiguisa and his
colleagues (31) demonstrated significant improved wear resistance in the
Zoysiagrass cultivar ‘Miyako.’ Foliar spraying potassium silicate at 1.1 or 2.2 kg
of Si per ha, or applying 22.4 kg/ha as a soil drench, also significantly reduced
b
y around 20% the injury caused by wear to seashore paspalum (36). However,
K alone or together with Si provided the same effect. In another study, several
cultivars of creeping bentgrass and Zoysiagrass had improved turf quality,
growth, and resistance to traffic and heat stress (24). Under severe drought
stress, Si-fertilized St. Augustinegrass plants had a better response than those
non-fertilized (36). Leaf firing and density were significantly greater by 13 and
23.5%, respectively, in Si-fertilized plants. Quality, color, and density also were
significantly enhanced when fertilized with Si over the controls by 19, 13.6, and
8.5%, respectively. However, under these test conditions, visual scores were all
b
elow what would be considered acceptable for turfgrass use. Nevertheless, this
demonstrates that Si may improve these turfgrass qualitative factors under
extreme drought stress. Schmidt and his associates (34) also showed that foliar
applications of Si significantly enhanced photosynthetic capacity increasing
chlorophyll content especially during the summer when plants were influenced
y environmental stress.
Gussak and his associates (15) demonstrated increased growth and
establishment of creeping bentgrass (Agrostis palustris Huds.) fertilized with Si.
Brecht et al. (4) and Datnoff et al. (5) also demonstrated similar results in St.
A
ugustinegrass. A percent bare ground coverage (vertical prostrate growth)
rating was recorded 11 to 12 weeks after sprigging a field with St. Augustinegrass
b
y estimating a visual percent area of bare ground covered by grass in a 2-m
2
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area (4). They demonstrated that the final percent bare ground coverage was
significantly increased by using Si by 17 to 24% over the control. Ten months
after sprigging, one pallet containing 46 m
2
of St.Augustinegrass was harvested
from each treatment-silicon and a control (5). Sod pieces (mat), 30 × 61 cm,
were washed to remove soil, dried for 48 h, and weighed. In addition, fresh,
intact sod pieces (mats) from each treatment were transplanted to a sand site
and monitored for turf quality and root length development for 21 days. At
harvest, the treatment that had been fertilized with Si had a dry sod mat weight
that was 13% significantly higher than the control. Sod pieces amended with Si
also had improved turf quality ratings, 7.1 to 7.6 versus 6.6 to 7.1 in comparison
to the non-fertilized control, 14 and 21 days after being transplanted to the field.
In addition, Si treatments had a significantly greater increase in newly-
generated roots, 0.8 to 1 cm in root length, in comparison to the non-fertilized
control.
Silicon also has been effective in suppressing diseases in a number of warm-
and cool-season turfgrass species (Table 1). Silicon has increased the resistance
of zoysiagrass to Rhizoctonia solani (31); creeping bentgrass to Pythium
aphanidermatum, Sclerotinia homoeocarpa, and R. solani (15,28,30,34,37);
and in Kentucky bluegrass to powdery mildew (Sphaerotheca fuliginea) (16).
Gray leaf spot development was reduced by Si over a range of 19 to 78% on
several cultivars of St. Augustinegrass under greenhouse conditions (7) (Fig. 1).
In field experiments, Si alone was compared to foliar sprays of chlorothalonil
and of Si plus chlorothalonil for managing gray leaf spot development (4). Gray
leaf spot was reduced by 17 to 27%, 31 to 63%, and 56 to 64% for Si alone,
chlorothalonil alone, and Si plus chlorothalonil, respectively, compared to a
non-treated control. Recently, Nanayakkara et al. (27) demonstrated similar
results in perennial ryegrass turf. They showed that gray leaf spot severity was
reduced from 11 to 24%.
Datnoff and Rutherford (9) recently evaluated the ability of Si to enhance
disease resistance in ‘Tifway’ bermudagrass to Bipolaris cynodontis, the cause o
f
leaf spot and melting out. They found that plants fertilized with Si had 39%
fewer lesions than plants non-fertilized (Fig. 2). This was also the first
experiment to demonstrate that bermudagrass accumulates Si. Silicon increased
in leaf tissues 38 to 105% over the control.
A
B
Fig. 1. Influence of silicon on gray leaf spot development in St.
Augustinegrass.
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Mechanism(s) of Silicon-Mediated Resistance to Plant Diseases
The effect of Si on plant resistance to disease is considered to be due either to
an accumulation of absorbed Si in the epidermal tissue, and/or expression of
pathogensis-induced host defense responses. Accumulated monosilicic acid
polymerizes into polysilicic acid and then transforms to amorphous silica, which
forms a thickened Si-cellulose membrane (18). By this means, a double cuticular
layer protects and mechanically strengthens plants. Silicon also might form
complexes with organic compounds in the cell walls of epidermal cells, therefore
increasing their resistance to degradation by enzymes released by fungi (8).
Research also points to the role of Si in planta as being active and this
suggests that the element might amplify the response for inducing defense
reactions to plant diseases. Silicon has been demonstrated to stimulate chitinase
activity and rapid activation of peroxidases and polyphenoxidases after fungal
infection (3). Glycosidically bound phenolics extracted from Si amended plants
when subjected to acid or B-glucosidase hydrolysis displayed strong fungistatic
activity. More recently, flavonoids and momilactone phytoalexins, low molecular
weight compounds that have antifungal properties, were found to be produced
in both dicots and monocots, respectively, fertilized with Si and challenge
inoculated by the pathogen in comparison to non-fertilized plants also
challenged inoculated by the pathogen. These antifungal compounds appear to
b
e playing an active role in plant disease suppression (14,29).
Table 1. Turfgrass, disease, and plant pathogen response to silicon.
x
Silicon applied as calcium silicate or potassium silicate decreased (<) disease
intensity.
A
B
Fig. 2. Influence of silicon on Bipolaris leaf spot development in
bermudagrass.
Turfgrass Disease Pathogen Effect
x
Reference(s)
Zoysiagrass Leaf blight Rhizoctonia solani < (31)
Creeping
bentgrass
Root rot Pythium
aphanidermatum
< (15,28,30,34,37)
Brown patch Rhizoctonia solani <
Dollar spot Sclerotinia
homoeocarpa
<
Kentucky
bluegrass
Powdery
mildew
Sphaerotheca
fuliginea
< (16)
Bermudagrass Leaf spot Bipolaris cynodontis < (9)
St. Augustine-
grass
Gray leaf
spot
Magnaporthe grisea < (4,7)
Perennial
ryegrass
Gray leaf
spot
Magnaporthe grisea < (27)
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Outlook and Future for Silicon in Turfgrass Performance
That Si plays an important role in the mineral nutrition of plant species such
as rice and sugarcane is not in doubt nor is its ability to enhance plant
development and efficiently control plant diseases. Now evidence is
accumulating that similar effects occur in certain turfgrasses. Effective, practical
means of application, affordable sources of Si, and methods for identifying
conditions under which Si fertilization will be beneficial are needed for use in
turfgrass management. However, research on the use of Si for turfgrass is in its
infancy. For example, no soil tests for gauging amounts of plant-available Si
have been calibrated for turfgrass. Furthermore, most analytical laboratories do
not routinely assay plant tissue for Si. In fact, the current standard tissue
digestion procedures used in most laboratories would render Si insoluble,
making an analysis of the digested tissue meaningless. Thus, the two analytical
tools most often used for determining the need for fertilization with plant
nutrients are not widely available for Si. While a number of beneficial responses
of turfgrass to Si applications have been documented in controlled experiments,
particularly in the laboratory, few large-scale field effects have been observed to
date. Conditions under which beneficial responses to Si fertilization will occur
are not well known for turfgrass.
Nevertheless, as the need for environmentally friendly strategies for
management of abiotic and biotic stress increases, Si could provide a valuable
tool for use in plants capable of its accumulation. The use of Si for improving
plant performance while controlling plant diseases in turf would be well-suited
for inclusion in integrated pest management strategies and would permit
reductions in fungicide use. As researchers and turfgrass managers become
aware of Si and its turf potential, it is likely that this often overlooked element
will be recognized as a viable means of enhancing turfgrass health and
performance.
Literature Cited
1. Adatia, M. H., and Besford, R. T. 1986. The effects of silicon on cucumber plants
grown in recirculating nutrient solution. Ann. Bot. 58:343-351.
2. Agarie, S., Agata, W., and Kaufman, P. B. 1998. Involvement of silicon in the
senescence of rice leaves. Plant Prod. Sci. 1:104-105.
3. Bélanger, R. R., Bowen, P. A., Ehret, D. L., and Menzies, J. G. 1995. Soluble silicon:
Its role in crop and disease management of greenhouse crops. Plant Dis. 79:329-
336.
4. Brecht, M. O., Datnoff, L. E., Kucharek, T. A., and Nagata, R. T. 2004. Influence of
silicon and chlorothalonil on the suppression of gray leaf spot and increase plant
growth in St. Augustinegrass. Plant Dis. 88:338-344.
5. Datnoff, L., Brecht, M., Kucharek, T., Trenholm, L., Nagata, R., Snyder G., Unruh,
B., and Cisar, J. 2005. Influence of silicon (Si) on controlling gray leaf spot and
more in St. Augustinegrass in Florida. TPI Turf News 3:30-32.
6. Datnoff, L. E., Deren, C. W., and Snyder, G. H. 1997. Silicon fertilization for disease
management of rice in Florida. Crop Prot. 16:525-531.
7. Datnoff, L. E., and Nagata, R. T. 1999. Influence of silicon on gray leaf spot
development in St.Augustinegrass. Phytopathology 89:S19.
8. Datnoff, L. E., and Rodrigues, F. A. 2005. The role of silicon in suppressing rice
diseases. Online. February APSnet Feature. American Phytopathological Society,
St. Paul, MN.
9. Datnoff, L. E., and Rutherford, B. A. 2004. Effects of silicon on leaf spot and melting
out in bermudagrass. Golf Course Manage. 5:89-92.
10. Datnoff, L. E., Snyder, G. H., and Korndorfer, G. H. 2001. Silicon in Agriculture.
Elseveir Science, The Netherlands.
11. Elawad, S. H., and Green, V. E. 1979. Silicon and the rice plant environment: A
review of recent research. Riv. Riso 28:235-253.
12. Epstein, E. 1994. The anomaly of silicon in plant biology. Proc. Natl. Acad. Sci. USA
91:11-17.
13. Epstein, E. 1999. Silicon. Annu. Rev. Plant Physiol. Plant Mol. Biol. 50:641-664.
14. Fawe, A., Abou-Zaid, M., Menzies, J. M., and Bélanger, R. R. 1998. Silicon-
mediated accumulation of flavonoid phytoalexins in cucumber. Phytopathology
88:396-401.
15. Gussack, E., Petrovic, M., and Rossi, F. 1998. Silicon: The universal contaminant.
Turfgrass Times 9:9-11.
14 Se
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tember 2005A
pp
lied Turf
g
rass Science
16. Hamel, S. C., and Heckman, J. R. 1999. Impact of mineral silicon products on
powdery mildew in greenhouse grown turf. Rutgers Turfgrass, vol. 31, Rutgers,
New Jersey.
17. Hodson, M. J., and Sangster, A. G. 2002. Silicon and abiotic stress. Pages 99-104
in: Second Silicon in Agriculture Conference. T. Matoh, ed. Press-Net, Kyoto,
Japan.
18. Hodson, M.J., and Sangster, A. G. 1988. Silica deposition in the influence bracts of
wheat (Triticum aestivum). 1 Scanning electron microscopy and light microscopy.
Can. J. Botany 66:829-837.
19. Hull, R. J. 2004. Scientists start to recognize silicon’s beneficial effects. Turfgrass
Trends 8:69-73.
20. Jones, L. H. P., and Handreck, K. A. 1967. Silica in soils, plants and animals. Ad.
Agron. 19:107-149.
21. Kang, Y. K. 1980. Silicon influence on physiological activities in rice. Ph.D. diss.,
University of Arkansas, Fayetteville, Arkansas.
22. Lee, K. S., Ahn, S. B., Rhee, G. S., Yeon, B. Y., and Park, J. K. 1985. Studies of silica
application to nursery beds on rice seedling growth. Farm Product Utilization
27:23-27.
23. Liang, Y. C., Shen, Q. R., Shen, Z. G., and Ma, T. S. 1996. Effects of silicon on
salinity tolerance of two barley cultivars. J. Plant Nutr. 19:173-183.
24. Linjuan, Z., Junping, J., Lijun, W., Min, L., and Fusuo, Z. 1999. Effects of silicon on
the seedling growth of creeping bentgrass and zoysiagrass. Pages 381 in: Silicon in
Agriculture. L. E. Datnoff, G. H. Snyder, and G. H. Korndorfer, eds. Elsevier
Science. Amsterdam, The Netherlands.
25. Ma, J., Nishimura, K., and Takahashi, E. 1989. Effect of silicon on the growth of
rice plant at different growth stages. Jpn. J. Soil Sci. Plant Nutr. 35:347-356.
26. Ma, J., and Takahashi, E. 2002. Soil, fertilizer and plant silicon research in Japan.
Elseveir Science, The Netherlands.
27. Nanayakkara, U. N., Uddin, W., and Datnoff, L. E. 2005. Effects of silicon on
development of gray leaf spot in perennial ryegrass turf. Phytopathology 95:S172.
28. North Carolina State. 1997. Effect of soluble silica on brown patch and dollar spot
of creeping bentgrass. No. Carolina Turfgrass, Aug./Sept.:34-36.
29. Rodrigues, F., McNally, D., Datnoff, L., Jones, J., Labbé, C., Benhamou, N.
Menzies, J., Bélanger, R. 2004. Silicon enhances the accumulation of diterpenoid
phytoalexins in rice: a potential mechanism for blast resistance. Phytopathology
94:177-183.
30. Rondeau, E. 2001. Effect of potassium silicates on disease tolerance of bentgrass.
Seminaire de fin d’etudes, Centre de Recherche en Horticulture, Université Laval,
Québec, Canada.
31. Saigusa, M., Onozawa, K., Watanabe, H., and Shibuya, K. 2000. Effects of porous
hydrate calcium silicate on the wear resistance, insect resistance, and disease
tolerance of turf grass "Miyako". Grassland Sci. 45:416-420.
32. Savant, N. K., Datnoff, L. E., and Snyder, G. H. 1997. Depletion of plant-available
silicon in soils: A possible cause of declining rice yields. Commun. Soil Sci. Plant
Anal. 28:1245-1252.
33. Savant, N. K., Snyder, G. H., and Datnoff, L. E. 1997. Silicon management and
sustainable rice production. Pages 151-199 in: Advances in Agronomy, vol. 58. D.
L. Sparks ed. Academic Press, San Diego, CA.
34. Schmidt, R. E., Zhang, X., and Chalmers, D. R. 1999. Response of photosynthesis
and superoxide dismutase to silica applied to creeping bentgrass grown under two
fertility levels. J. Plant Nutr. 22:1763-1773.
35. Takahashi, E., Ma, J. F., and Miyake, Y. 1990. The possibility of silicon as an
essential element for higher plants. Comments Agric. Food Chem. 2:99-122.
36. Trenholm, L. E., Datnoff, L. E. and Nagata, R. T. 2004. Influence of silicon on
drought and shade tolerance of St. Augustinegrass. HortTechnology 14:487-490.
37. Uriarte, R. F., Shew, H. D., and Bowman, D. C. 2004. Effect of soluble silica on
brown patch and dollar spot of creeping bentgrass. J. Plant Nutri. 27:325-339.
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... For example extra nitrogen content with high humidity level is suitable for pathogen like phytium and phytophtera growth and development on plants [185,186]. In turfgrasses by adding Mn and Si elements to the nutrient solution, the grasses overcome disease easier and faster [190]. Plants with sufficient nutrient supplies recover more and faster than the nutrient deficient plants from the insect's injury. ...
... Plants with sufficient nutrient supplies recover more and faster than the nutrient deficient plants from the insect's injury. In a research by using Al and Si for turfgrass growth medium, these elements protected the plants from the insect injuries and also helped them to make an unattractive compound for the insects diet [190]. ...
... In studies, the addition of Al and Si to a turfgrass growth medium shielded the plants from insect attacks while also assisting them in producing an unattractive substance for the insects to consume [104]. The concept of agroforestry is based on the predicted contribution of on-farm and off-farm tree production in providing sustainable land use and natural resource management [105]. At the site level, the system's aboveground and belowground diversity provides better stability and resilience, while at the landscape and bioregion levels, the system provides connectivity with forests and other natural landscapes [106]. ...
... In studies, the addition of Al and Si to a turfgrass growth medium shielded the plants from insect attacks while also assisting them in producing an unattractive substance for the insects to consume [104]. The concept of agroforestry is based on the predicted contribution of on-farm and off-farm tree production in providing sustainable land use and natural resource management [105]. At the site level, the system's aboveground and belowground diversity provides better stability and resilience, while at the landscape and bioregion levels, the system provides connectivity with forests and other natural landscapes [106]. ...
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Within the periodic table, metalloids are highlighted as a separate class of essential micronutrients which show chemical properties between metals and non-metals. Along with other elements, these metalloids are instrumental in governing plant’s growth, biomass, health, development, metabolism, reproduction and productivity. However, due to modern agricultural practices, rapid industrialization, burning of fossils fuels, military operations, metalliferous mining and anthropogenic activities, there has been an increase in the threshold level of various metals and metalloids in the past 50 years. As a result, the long-term effects of various metalloids have been assessed on the environment, human, livestock and plant health throughout the last two decades. Parallely, the information about bioavailability, accumulation, uptake and metabolism within the plant at various cellular sites has been gathered. One of the relevant components of metalloid which orchestrate the metalloid uptake, translocation and sequestration are metalloid transporters. Therefore, in this chapter, we have highlighted the metalloid sources, beneficial roles, distribution, uptake and transporters.
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As a result of silicon research from the 1980s until today, a number of facts can be stated about the role this element plays in plant disease suppression. These include the following: for any plant disease, a minimum silicon concentration is needed to suppress that disease; once that lev l has been obtained, plant disease suppression increases proportionally as the silicon concentration (insoluble or soluble) increases in plant tissues; the silicon supply to a plant must be continuous or the disease-suppressing effects will be reduced or non-existent; silicon can infl uence many components of host resistance; silicon may augment susceptible and partial resistance almost at the same level as complete genetic resistance; only when applying silicon to the roots will this element mediate plant defenses at both the physiological and molecular level; and silicon may suppress plant diseases as effectively as fungicides. In spite of the recent advances linking silicon to host resistance via the -“omics”™, namely, genomics, proteomics and metabolomics, the exact mechanism(s) by which this element modulates plant physiology through anincrease in host resistance requires further investigation. Silicon undoubtedly deserves more attention by scientists and agriculturalists, but its recognition is limited by current perspectives on whether agricultural soils are truly low in this element, whether the plant in question will accumulate silicon and whether silicon is to be viewed as a fertilizer, biostimulant or plant protectant. Nevertheless, as researchers and growers become more aware of silicon and its potential, it is likely that this often overlooked, quasi-essential element will be recognized as a viable means of enhancing plant health and performance
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Cucumber plants (Cucumis sativus) cv. Corona were grown in recirculating nutrient solution containing either 10 mg l-1 SiO2 (low Si) which was the level present in the water supply or given an additional 100 mg l-1 SiO2 (high Si). Silicate was depleted from the solution when cucumbers were grown, but accumulated when tomatoes were grown. Major effects on cucumber leaves of added Si were: increased rigidity of the mature leaves which had a rougher texture and were held more horizontally; they were darker green and senescence was delayed. The mature high Si leaves acquired characteristics of leaves grown in a higher light intensity, i.e. they had shorter petioles and an increased fresh weight per unit area, dry weight per unit area, chlorophyll content, RuBPcarboxylase activity and soluble protein (all expressed per unit area of interveinal laminar tissue). Addition of Si did not affect the final leaf area of the mature leaves but root fresh weight and dry weight were increased. A pronounced effect of Si addition was the increased resistance to the powdery mildew fungus Sphaerotheca fuliginea. Despite regular applications of fungicide, outbreaks of the fungal disease occurred on most of the mature leaves on the low Si plants, while the high Si plants remained almost completely free of symptoms. The addition of Si could be beneficial to cucumbers grown in areas where the local water supply is low in this element, especially when grown in recirculating solution or in a medium low in Si, e.g. peat.
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The objectives of these studies were to evaluate the effects of silicon on drought and shade tolerance of st. augustinegrass (Stenotaphrum secundatum). Studies were conducted during 2001 in a glasshouse at the University of Florida Turfgrass Research Envirotron in Gainesville. For both drought and shade evaluations, calcium silicate slag (CaSiO3) was pre-incorporated into pots with commercial potting soil at the rate of 3.36 kg·ha-1 (0.069 lb/1000 ft2). 'FX-10' and 'FHSA-115' st. augustinegrass were planted into 15.2-cm-diameter x 30.5-cm-deep (6 x 12 inches) plastic pots for the drought study and subjected to minimal irrigation. Under severe drought stress, silicon-amended plants had better responses than non-amended plants. Little improvement was seen under moderate drought stress. 'Floratam' and genotype 1997-6 were placed under full sunlight or 50% to 70% shade. There was no benefit from use of silicon under shaded conditions. These findings suggest that silicon might provide improved tolerance to st. augustinegrass under severe drought stress.
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Field trials were conducted at Exp. Farm of Tohoku univ., Naruko, Japan in 1997 to examine the effects of porous hydrate calcium silicate (PS) on the wear resistance, insect resistance and disease tolerance of turf grass using a new turf grass cultivar "Miyako". Silica content of Miyako leaves treated with PS 100 and 300g/m^2 increased by 18 and 26%, respectively, compared to that of the control. With the application of 300 g/m^2 PS, tractions of turf leaves at 4 cm and 6 cm height, indicators of wear resistance, significantly (P<0.05) increased by 7.0% and by 9.0%, respectively, compared to that of the control. With PS 300 g/m^2 treatment, feeding amount of turf leaves by Rusidriaa depravata BUTLER larvae significantly decreased by 41% (P<0.05) compared to that of the control. Degrees of disease severity affected with the brown large patch (Rhizoctonia solani) tended to be reduced by PS application. In conclusion, porous hydrate calcium silicate is an effective material for improving the wear resistance, insect resistance and disease tolerance of turf grass "Miyako".
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Publisher Summary This chapter discusses several aspects of silica in the chain from soil through plant to animal. Soil solution is the immediate source of the silica that is always absorbed by soil-grown plants. The factors affecting the silica content of plants include: soil pH and the content of iron and aluminum oxides present in plants. Plants take up different amounts of silica, according to their species. Silicon sometimes has a beneficial effect through alleviating manganese toxicity. Silicon alters the distribution of manganese in the leaf tissues, thereby preventing it from collecting into localized areas that become necrotic. The presence of silica in pasture plants ensures that grazing ruminants ingest rather large amounts of silica, most of which is in the solid form. Apart from slight dissolution, this silica is unchanged in passing along the alimentary tract and its known effects on the animal are physical or mechanical. The dissolved silica that is absorbed from the alimentary tract is carried to the kidney and excreted in the urine. Although it is normally excreted readily, the silica is sometimes deposited to form calculi or uroliths that can cause serious economic loss.
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Rice plants (Oryza sativa L. cv. Akebono) were cultured in Kimura B solution. The effect of silicon on plant growth and the characteristics of the uptake and distribution of silicon at different growth stages were studied from both aspects: the addition and removal of silicon during the vegetative, reproductive and ripening stages.When silicon was removed during the reproductive stage, the dry weights of straw (stem+leaf blade) and grain decreased by 20 and 50% respectively, compared with those of the plants cultured in the solution with silicon throughout the growth period. Conversely, when silicon was added during the reproductive stage, the dry weights of straw and grain increased by 243 and 30%, respectively, over those of the plants cultured in a solution devoid of silicon throughout the growth period. The effect of silicon on the dry weights of straw and grain was small when silicon was either added or removed during the vegetative and ripening stages.The percentage of filled spikelets remarkably increased or decreased when silicon was added or removed during the reproductive stage. The 1,000-grain weight was hardly influenced by the addition or removal of silicon regardless of the growth stage.About 66% of silicon in the whole plant and 70 to 75% of silicon in the leaf blades were absorbed during the reproductive stage. About 75% of silicon in the panicle was absorbed during the ripening stage although no beneficial effect was detected in this experiment.Forty to 50% of the silicon absorbed during the vegetative and reproductive stages was present in the leaf blades, whereas only 20 to 30% of silicon absorbed during the ripening stage was present in the leaf blades.Based on these results, it is concluded that the supply of silicon during the reproductive stage is most important for plant growth.