Sci. Agri.
8 (2), 2014: 80-85
© PSCI Publications
Scientia Agriculturae
www.pscipub.com/SA
E-ISSN: 2310-953X / P-ISSN: 2311-0228
DOI: 10.15192/PSCP.SA.2014.4.2.8085
The Ameliorative effects of silicon element on improvement of
plants tolerance to diseases
Vahid Ghazi Mohseni1 and Seyed Kazem Sabbagh2
1. MSc student of plant pathology, University of Zabol, Iran
2. Assistant professor, faculty of plant pathology, University of Zabol, Iran
Corresponding author email: [email protected]
Paper Information
Received: 16 September, 2014
Accepted: 20 October, 2014
Published: 20 November, 2014
ABSTRACT
Silicon is the second most plentiful element in soil and is beneficial for a
large variety of plants. It is concentrated in plant tissues in quantities
similar to that of macronutrients. Considerable damages to plants caused
by abiotic stresses such as drought stress, salinity stress, heavy metal stress
and nutrient imbalance, as well as biotic stresses like insect pests and
pathogens and even herbivorous attacks, have been reported to be reduced
significantly by silicon application. It seems that better understanding
about the function of silicon in plant would be help to improve production
in areas with soils poor in silicon, since it has been known to have the
ability to lessen vulnerability of plant against different kinds of diseases. Si
provides many benefits to stressed plants including protection against
attack from certain fungal, bacterial and virus pathogens. The studies have
shown that silicon fertilization to be efficacious in controlling and
mitigating severity of some diseases such as rice blast, powdery mildew,
bacterial wilt, bacterial speck Tobacco ringspot virus and tobacco mosaic
virus. Thus, more knowledge about silicon function can help farmers and
agriculture industry to manage and control diseases effectively.
© 2014 PSCI Publisher All rights reserved.
Key words: disease, plant, silicon, yield
Introduction
The silicon (Si) is an abundant element in terrestrial superficie (Pereira et al., 2003), however its availability to plants
is normally low (Hattori et al., 2005). According to Matichenkov and Calvert (Matichenkov and Calvert, 2002), the chemically
active Si forms in soil are represented by soluble monosilicic acid (Si (OH)4) that is soluble and weakly adsorbed, as well as
acid polisilicic, which are compound organosilicates. Si is considered an benefic element to higher plants (Epstein and Bloom,
2004), being that the absorption process must be active or passive (Ma et al., 2007), and deposition in cell walls of several
organs such as leaf and stem can promote beneficial effects (Cunha et al., 2008), and for this reason has been frequently linked
to physiological, morphological, nutritional, and molecular aspects in plants (Isa et al., 2010; Ma et al., 2004; Ma and Yamaji,
2006; Lobato et al., 2009). In plants this nutrient is assimilated mainly by roots, and capacity to accumulate in tissues is
variable (Chiba et al., 2009), being several monocots such as Oryza sativa and Triticum aestivum considered silicon
accumulator, with absorption active by root system, and it present leaf levels normally higher that 10.0 g kg-1 of Si (Oliveira,
2009). In other hand, many dicots like as Phaseolus vulgaris and Glycine max are characterized as not accumulator of silicon,
and its presents passive absorption, with leaf tenors minors that 5.0 g kg-1 of Si (Takahashi et al., 1990). In tissues, about of
99% of silicon is found in silic form and less than 1% is colloidal or ionic form, which is the soluble form (Ma et al., 2001).
Therefore, the storage sites of silicon in plants normally are responsible to improve leaf and plant architectures and also others
metabolic processes like as gas exchanges (Pereira et al., 2012), photosynthetic pigments (Silva et al., 2012), and antioxidant
system (Li et al., 2012), in which it results in better performance linked to growth, development, and yield parameters (Nolla et
al., 2012). The positive impacts of silicon in improving plant growth and yield are significant, and these include increasing
resistance against environmental stresses such as cold and salinity stress, insect attacks and penetration of pathogens (Jones
and Handreck, 1967; Elawad and Green, 1979; Belanger et al., 1995; Savant et al., 1996). In addition to what has been
mentioned above, using appropriate amount of silicon has been found to reduce the probability of plants being grazed by
herbivores (Rodrigues and Datnoff, 2005; Belanger et al., 1995; Datnoff et al., 1997; Savant et al., 1996). Meanwhile, a large
number of valuable investigations have been conducted on the positive effects of silicon in plants (Abed Ashtiani et al., 2012).
Sci. Agri. 8 (2), 2014: 80-85
Typically in soils with low amounts of silicon, silicon fertilization has been applied to increase both the quality and quantity of
agricultural crops such as rice and sugar cane (Korndorfer and Lepsch, 2001). In addition, foliar applications of silicon have
been confirmed to increase the resistance against pathogens in plant species that do not absorb silicon efficiently (Epstein,
1994; Bowen et al., 1992). Recent research has demonstrated that both foliar and soilborne diseases of cucumber and other
cucurbits can be suppressed by applying this element (Belanger et al., 1995). Much of the research on silicon has been focused
on rice, although its benefits to other crops such as wheat and corn have also been proven (Wang et al., 2001). The goal of this
paper is to review the research findings in relation to silicon and plant diseases.
Silicon deficiency in the soil
Silicon (Si) is one of the most abundant elements in the earth’s crust and most soils contain considerable quantities of
the element (Epstein, 1994). However, repeated cropping can reduce the levels of plant available Si to the point that
supplemental Si fertilization is required for maximum production and some soils contain little plant-available Si in their native
state. Low-Si soils are typically highly weathered, leached, acidic and low in base saturation. Thus, highly weathered soils
such as Oxisols and Ultisols can be quite low in soluble Si (Foy, 1992). Highly organic Histosols that contain little mineral
matter may contain little Si. Interestingly, soils comprised mainly of quartz sand (SiOz) such as sandy Entisols also may be
very low in plant-available Si. These conditions are found in many crop-producing areas of Africa, Asia, Latin America and
the southeastern USA.
Genotype and silicon interactions
Effective disease-control strategies for agronomic crops, in particular, include the incorporation of genetically
controlled resistance into cultivars. Since genotypes vary in disease resistance, the relationship between Si content among
genotypes and disease resistance was investigated. In a test of 18 rice cultivars grown at three locations representing high (116
mg Si L-1 soil), typical (40 mg Si L-1 soil) and low (6 mg Si L-1 soil) soil Si status, cultivars varied significantly for tissue Si
concentration (Deren et al., 1992). Certain genotypes consistently ranked high or low in Si concentration across all locations.
This suggested that the acquisition of Si may be an inherited trait. Similar variations in Si concentration have been reported for
African japonicas (Winslow, 1992). Genotypes were further evaluated for Si accumulation and brown spot development on a
low-Si soil fertilized with 0 and 2 Mg Si ha-1 (Deren et al., 1994). Genotypes varied significantly for Si concentration in plant
tissue. However, the range among genotypes was very narrow. Rico 1 and Della X2 tended to have the greatest Si
concentrations in both Si-deficient and Si-amended soils (Datnoff et al., 1997).
The suppressive effect of silicon on fungal diseases
Rice blast (Pyricularia oryzae)
Several researchers have demonstrated that silicon application has a suppressive effect on fungal diseases such as rice
blast (Magnaporthe grisea, teleomorph, Pyricularia oryzae, anamorph), brown spot (Cochliobolus miyabeanus, teleomorph;
Bipolaris oryzae, anamorph), leaf scald (Gerlachia oryzae), sheath blight (Rhizoctonia solani, teleomorph) and stem rot
(Sclerotium oryzae, teleornorph) (Datnoff et al., 1991, 1997; Savant et al., 1997; Seebold, 1998; Winslow, 1992). Under
silicon deficient conditions, some diseases such as blast, brown spot and sheath blight can be extremely threatening to rice
cultivation (Rodrigues and Datnoff, 2005). Accumulated silicon in rice tissues enhances resistance against insects and diseases,
increases erectness of leaves resulting in increased photosynthesis, improves water usage, and decreases toxicity of heavy
metals and cuticular transpiration (Nakata et al., 2008; Epstein, 1994). The amounts of silicon accumulated in rice plants can
be as much as 10% of plant dry weight. It is often several times higher than the rate of accumulation of other essential macro
nutrients such as nitrogen, phosphorus and potassium (Nakata et al., 2008; Ma et al., 2006). Rice blast disease, caused by the
fungus Pyricularia oryzae (Couch and Kohn, 2002), is particularly prevalent in all areas under rice cultivation and it also
causes heavy yield losses (Nakata et al., 2008; Ou, 1985). Development of efficient and cost-effective methods to manage the
disease is one of the priority issues in rice production (Hayasaka et al., 2008). There are many management methods that are
being evaluated for rice blast disease management and these include, among others, breeding of resistant varieties (time
consuming) and management methods to improve soil nutrients (Hayasaka et al., 2008). The minimum amount of silicon
needed to control blast disease in rice is 3-5% (Datnoff et al., 1997). Positive effects and importance of silicon as a nutrient
element in rice plants have been reported in several studies (Hayasaka et al., 2008; Ando et al., 2002; Ma et al., 2006;
Kamenidou et al., 2009; Deren et al., 1992; Ma and Takahashi, 2002; Gao et al., 2004) and a gene which plays a role in the
transport of silicon has also been detected (Hayasaka et al., 2008; Ma et al., 2006). There are different hypotheses on how
silicon confers and induces resistance to some plants specially rice against diseases such as blast (Ishiguro, 2001). These
hypotheses can be classified into two groups (Hayasaka et al., 2008). One hypothesis is based on the belief that silicon acts as a
mechanical barrier against fungal penetration (Hayasaka et al., 2008) which is also known as physical resistance, while the
second hypothesis is based upon physiological resistance.
81
Sci. Agri. 8 (2), 2014: 80-85
Powdery mildew (Golovinomyces cichoracearum)
Gerbera (Gerbera jamesonii) is among the major greenhouse grown cut flowers in the United States. Powdery mildew
caused by Golovinomyces cichoracearum (syn. Erysiphe cichoracearum) is one of the most destructive diseases of gerbera
(Malathrakis and Goumas, 1999). Golovinomyces cichoracearum forms white powdery blotches on leaves and other green
parts of gerbera, resulting in increased water loss, reduced photosynthesis and, consequently, reduced quality of flowers. In
commercial situations, control of powdery mildew on gerbera has involved frequent applications of fungicides.
Environmentally friendly, effective alternatives to fungicides for management of powdery mildew are deemed desirable. Due
to the Food Quality Protection Act (FQPA) of 1996, many fungicides currently used to control diseases in floriculture crops
are at risk of de-registration by the Environmental Protection Agency (EPA). In addition, powdery mildew fungi can develop
resistance to conventional fungicides. Therefore, research is needed to identify alternatives to conventional fungicides. A
promising alternative to conventional fungicides for control of powdery mildew on gerbera is the element silicon (Si). In
highly relevant work conducted in Florida, applications of Si (calcium silicate) resulted in dramatic reductions of two foliar
fungal diseases of rice (Datnoff et al., 1991). Although calcium silicate contains other nutrients, only Si increased within plant
tissues and correlated with disease reduction. In some cases, Si use provided disease control equivalent to that of fungicides in
both rice and turf (Datnoff et al., 2001 and Brecht et al. 2004). In addition, fungicide rates could be reduced when used in
combination with this element (Seebold et al., 2004). More recently, Seebold et al (2000) and Rodrigues et al (2001)
demonstrated that host resistance of susceptible and partially resistant cultivars can be augmented with Si to the same general
level as those containing complete disease resistance. When a Si source such as calcium silicate is incorporated in potting
media low in plant available Si, Si is taken up by plants via the root system at higher rates than other elements and enhances
plant growth as well as the defense response of plants to pathogen attack. Recent research demonstrated that Si can play a role
in enhancing the growth and appearance of flowering ornamentals. Savvas et al. (2002) showed that Si in the nutrient solution
resulted in significantly thicker flower stems and a higher proportion of flowers graded Class I for gerbera (Gerbera
jamesonii). Shoot number, flower number, dry weight were enhanced by 25, 62 and 66 %, respectively, over the control for
paper daisies (Helichrysum adenohorum) amended with Si (Muir et al., 1999). In a similar study, open flowers per head were
increased by 28% in snapdragons while bent/lodged stems were reduced by 33%. More recently, black spot infection of Rosa
hybrida ‘Meipelta’ was demonstrated to be suppressed by the addition of 150 mg/L Si as potassium silicate to irrigation water
(Gillman et al., 2003).
The role of silicon on plant responses to the bacterial diseases
Bacterial wilt (Ralstonia solanacearum)
Diseases caused by different fungal and bacterial pathogens (Jones et al., 1991) are among the major constraints of
tomato production. Bacterial wilt caused by Ralstonia solanacearum (Yabuuchi et al., 1995) is one of the most important
diseases that limit tomato production worldwide. The disease also constitutes a serious damage to the cultivation of many other
Solanaceous crops (potato, tobacco, pepper and eggplant) in tropical, sub-tropical and temperate regions (Hayward, 1991).
Different management strategies of bacterial wilt disease have been studied in many parts of the world with special focus on
host plant resistance, cultural practices, and soil amendments (Saddler, 2005). Silicon (Si) has been reported for having a
significant effect in reducing bacterial wilt incidence in tomato in a hydroponics culture system, and peat substrate (Dannon
and Wydra, 2004). Diogo and Wydra (2007) also reported an induced basal resistance on cell wall level, in silicon treated
tomato plants compared to non-treated plants. Thus, an elucidation of the effect of silicon amendment under field conditions,
for the management of bacterial wilt on tomato is necessitated. Ayana et al. (2011) have reported that silicon fertilizer
significantly reduced the bacterial population, mean wilt incidence, percent severity index, and corresponding areas of disease
incidence, and severity progress curves in the moderately resistant tomato cultivar. However, silicon fertilizer do not resulted
in any significant reduction of all disease parameters in the moderately susceptible cultivar Marglobe.
Bacterial speck (Pseudomonas syringae)
Bacterial speck caused by Pseudomonas syringae pv. tomato (Pst) is an economically important disease on tomato
crops (Silva and Lopes, 1995). Yield losses of up to 30% are reported in environments with high relative humidity and
temperature ranging from 20 to 25ºC (Silva and Lopes, 1995). The control of bacterial diseases is limited to the availability of
chemicals. Products containing copper and the inducer of resistance acibenzolar-S-methyl are the most used to control
bacterial speck (Lopes and Santos, 1994). Also, the use of cultivars containing the resistant Pto gene, such as the cultivar BRS
Tospodoro, is highly recommended to the growers (Lopes and Santos, 1994). Other control methods for bacterial speck remain
to be investigated. Silicon (Si) has been gaining attention in the control of certain fungal diseases, such as powdery mildew in
muskmelon and tomato (Dallagnol et al., 2012; Yanar et al., 2011). Dannon and Wydra (2004) obtained reduction in the
82
Sci. Agri. 8 (2), 2014: 80-85
symptoms of bacterial wilt (Ralstonia solanacearum) in tomato plants from susceptible and moderately resistant genotypes
supplied with Si. According to Diogo and Wydra (2007), the reduction in the symptoms of bacterial wilt occurred due to
changes in cell wall structure of the xylem vessels in plants supplied with Si. In the same pathosystem, Ghareeb et al. (2011)
found that the expression of genes related to basal defense of tomato was induced in plants supplied with Si and inoculated
with R. solanacearum, thereby, demonstrating the importance of Si in enhancing host defense responses.
Effect of silicon on virus diseases
Tobacco ringspot virus and tobacco mosaic virus
Si provides many benefits to stressed plants including protection against attack from certain fungal and bacterial
pathogens. For example, treatment of tomato varieties and Cucumis sativus with Si reduced infection by Ralstonia
solanacearum and Podosphaera xanthii, respectively (Dannon and Wydra, 2004). While Si protects plants against fungal and
bacterial pathogens, the effects of this element on viral infections are unclear. In an experiment in order to investigate the role
of Si in viral infections, hydroponic studies were conducted in Nicotiana tabacum with two pathogens: Tobacco ringspot virus
(TRSV) and Tobacco mosaic virus (TMV). Plants grown in elevated Si showed a delay in TRSV systemic symptom formation
and a reduction in symptomatic leaf area, compared to the non-supplemented controls. TRSV-infected plants showed
significantly higher levels of foliar Si compared to mock-inoculated plants. However, the Si effect appeared to be virusspecific, since the element did not alter TMV symptoms nor did infection by this virus alter foliar Si levels. Hence, increased
foliar Si levels appear to correlate with Si-modulated protection against viral infection. This is all the more intriguing since N.
tabacum is classified as a low Si accumulator (Zellner et al., 2011).
Conclusion
Although the function of silicon in plant is not wholly recognized, the application of this element would be an
encouraging method to improve production in areas with soils poor in silicon, since it has been known to have the ability to
lessen vulnerability of plant against different kinds of diseases, specifically those caused by fungal pathogens such as
Pyricularia oryzae. An important fact about silicon in addition of the aforementioned points is that it is an environmentally
friendly element in relation to soils, fertilizers and plant nutrition. Hence, it can be beneficial in IPM programs for those crops
where silicon has been proven to have a positive impact. The positive effects of silicon in plant nutrition and resistance against
diseases have been well established. Thus, providing the knowledge about silicon to farmers and rice growers will help the
agriculture industry to manage and control rice diseases effectively. Such efforts will ensure the production of safe food and
provide for adequate environmental protection (Abed Ashtiani et al., 2012).
References
Abed Ashtiani F, Kadir J, Nasehi A, Hashemian Rahaghi SR, Sajili H. 2012. Effect of silicon on rice blast disease. Pertanika J Tropic Agric Sci 35 (S): 1 –
12.
Ando H, Kakuda K, Fujii H, Suzuki K, Ajiki T. 2002. Growth and canopy structure of rice plants grown under field conditions as affected by Si application.
Soil Sci plant nutri 48(3): 429-432.
Ayana G, Fininsa C, Ahmed S, Wydra K. 2011. Effect of soil amendment on bacterial wilt caused by Ralstonia Solanacerum and tomato yields in Ethiopia. J
Plant Protec Res 51(1): 72-76.
Belanger RR, Bowen PA, Ehret DL, Menzies JG. 1995. Soluble silicon: its role in crop and disease management of greenhouse crops. Plant Dis 79(4): 329336.
Bowen P, Menzies J, Ehret D, Samuels L, Glass ADM. 1992. Soluble silicon sprays inhibit powdery mildew development on grape leaves. J American Society
Hortic Sci 117(6): 906-912.
Brecht MO, Datnoff LE, Kucharek TA, Nagata RT. 2004. Influence of silicon and chlorothalonil on suppression of gray leaf spot and increased plant growth
of St. Augustinegrass. Plant Dis 88:338-344.
Chiba Y, Mitani N, Yamaji N, Ma JF. 2009. HvLsi 1 is a silicon influx transporter in barley. Plant J 57: 810-818.
Couch BC, Kohn LM. 2002. A multilocus gene genealogy concordant with host preference indicates segregation of a new species, Magnaporthe oryzae, from
M. grisea. Mycologia, 94(4): 683-693.
Cunha KPV, Nascimento CWA, Accioly AMA, Silva AJ. 2008. Cadmium and zinc availability, accumulation and toxicity in maize grown in a contaminated
soil. Revista Brasileira de Ciência do Solo 3:1319-1328.
Dallagnol LJ, Rodrigues FA, Tanaka O, Amorim L, Camargo LEA. 2012. Effect of potassium silicate on epidemic components of powdery mildew on melon.
Plant Pathol 61:323-330.
Dannon EA, Wydra K. 2004. Interaction between silicon amendments, bacterial wilt development and phenotype of Ralstonia solanacearum in tomato
genotypes. Physiol Mol Plant Pathol 64: 233–243.
Datnoff LE, Deren CW, Snyder GH. 1997. Silicon fertilization for disease management of rice in Florida. Crop Protec 16(6): 525-531.
Datnoff LE, Raid RN, Snyder GH, Jones DB. 1991. Effect of calcium silicate on blast and brown spot intensities and yields of rice. Plant Dis 75(7): 729-732.
Datnoff LE, Seebold KW, Correa-V FJ. 2001. The use of silicon for integrated disease management: reducing fungicide applications and enhancing host-plant
resistance. In: Silicon in Agriculture. Datnoff LE, Snyder GH, Korndorfer GH (ed), Elseveir Science, The Netherlands.
Deren C, Datnoff L, Snyder G. 1992. Variable silicon content of rice cultivars grown on everglades histosols. J plant nutri 15(11): 2363-2368.
Deren CW, Datnoff LE, Snyder GH. Martin FG. 1994. Silicon content, disease response and components of yield of rice genotypes grown on flooded organic
Histosols. Crop Sci 34: 733-737.
83
Sci. Agri. 8 (2), 2014: 80-85
Diogo RVC, Wydra K. 2007. Silicon-induced basal resistance in tomato against Ralstonia solanacearum is related to modification of pectic cell wall
polysaccharide structure. Physiol Mol Plant Pathol 70 (4–6): 120–129.
Elawad SH, Green VE. 1979. Silicon and the rice plant environment: A review of recent research. Il Riso 28: 235-253.
Epstein E, Bloom AJ. 2004. Mineral nutrition of plants: principles and perspectives. Sinauer Associates, Sunderland.
Epstein E. 1994. The anomaly of silicon in plant biology. Proceedings of the National Academy of Sciences 91(1): 11-17.
Foy CD. 1992. Soil chemical factors limiting plant root growth. Advances Soil Sci 19: 97- 149
Gao X, Zou C, Wang L, Zhang F. 2004. Silicon improves water use efficiency in maize plants. J plant nutri 27(8): 1457- 1470.
Ghareeb H, Bozsó Z, Ott PG, Repenning C, Stahl F, Wydra K. 2011. Transcriptome of silicon-induced resistance against Ralstonia solanacearum in the silicon
non-accumulator tomato implicates priming effect. Physiol Mol Plant Pathol 75:83-89.
Gillman JH, Zlesak DC, Smith JA. 2003. Applications of potassium silicate decrease black spot infection in Rosa hybrida ‘Meipelta’ (Fuschia MeidilandTM).
HortScience 38:1144-1147.
Hattori T, Inanaga S, Araki H, An P, Morita S, Luxová M, Lux A. 2005. Application of silicon enhanced drought tolerance in Sorghum bicolor. Physiologia
Plantarum 123: 459-466.
Hayasaka T, Fujii H, Ishiguro K. 2008. The role of silicon in preventing appressorial penetration by the rice blast fungus. Phytopathol 98(9): 1038-1044.
Hayward AC. 1991. Biology and epidemiology of bacterial wilt caused by Pseudomonas solanacearum. Ann Rev Phytopathol 29: 65–87.
Isa M, Bai S, Yokoyama T, Ma JF, Ishibashi Y, Yuasa T, Iwaya-Inoue M. 2010. Silicon enhances growth independent of silica deposition in a low-silica rice
mutant, lsi1. Plant Soil 331: 361-375.
Ishiguro K. 2001. Review of research in Japan on the roles of silicon in conferring resistance against rice blast. Studies Plant Sci 8: 277-291.
Jones JB, Jone JP, Stall RE, Zitter TA. 1991. Compendium of Tomato Diseases. The APS Press, St. Paul, MN, USA, 73 pp.
Jones L, Handreck K. 1967. Silica in soils, plants, and animals. Advances Agron 19(2): 107-149.
Juo ASR, Sanchez PA. 1986. Soil nutritional aspects with a view to characterize upland rice environments. Paper presented at the 2nd International Upland
Rice Conference.
Kamenidou S, Cavins TJ, Marek S. 2009. Evaluation of silicon as a nutritional supplement for greenhouse zinnia production. Scientia Horticulturae 119(3):
297-301.
Korndorfer G, Lepsch I. 2001. Effect of silicon on plant growth and crop yield. Studies Plant Sci, 8: 133-147.
Li P, Song A, Li Z, Fan F, Liang Y. 2012. Silicon ameliorates manganese toxicity by regulating manganese transport and antioxidant reactions in rice (Oryza
sativa L.). Plant Soil 354: 407-419.
Lobato AKS, Coimbra GK, Neto MAM, Costa RCL, Santos Filho BG, Oliveira Neto CF, Luz LM, Barreto AGT, Pereira BWF, Alves GAR, Monteiro BS,
Marochio CA. 2009. Protective action of silicon on relations and photosynthetic pigments in pepper plants induced to water deficit. Res J Biol Sci 4:
617-623.
Lopes CA, Santos JRM. 1994. Doenças do tomateiro. Brasília DF, Brazil. Embrapa Hortaliças.
Ma JF, Mitani N, Nagao S, Konishi S, Tamai K, Iwashita T, Yano M. 2004. Characterization of the silicon uptake system and molecular mapping of the
silicon transporter gene in rice. Plant Physiol 136: 3284-3289.
Ma JF, Miyake Y, Takahashi E. 2001. Silicon as a beneficial element for crop plants. In: Datnoff LE, Snyder GH, Korndörfer GH (ed). Silicon in agriculture.
Amsterdan: Elsevier.
Ma JF, Takahashi E. 2002. Soil, fertilizer, and plant silicon research in Japan: Elsevier Science.
Ma JF, Tamai K, Yamaji N, Mitani N, Konishi S, Katsuhara M, Ishiguro M, Murata Y, Yano M. 2006. A silicon transporter in rice. Nature 440: 688-691.
Ma JF, Yamaji N, Mitani N, Tamai K, Konishi S, Fujiwara T, Katsuhara M, Yano M. 2007. An efflux transporter of silicon in rice. Nature 448: 209-212.
Ma JF, Yamaji N. 2006. Silicon uptake and accumulation in higher plants. Trends Plant Sci 11: 342-397.
Malathrakis NE, Goumas DE. 1999. Fungal and bacterial diseases. In: Integrated Pest and Disease Management in Greenhouse Crops. Albajes R, Gullino ML,
van Lenteren JC, Elad Y (ed). Kluwer Academic Publishers. Dordrecht.
Matichenkov VV, Calvert DV. 2002. Silicon as a beneficial element for sugarcane. J American Society Sugarcane Technol 22: 21-30.
Muir S, Khoo C, McCabe B, Fensom G, Offord C, Brien J, Summerell B. 1999. Some effects of silicon in potting mixes on growth and protection of plants
against fungal diseases. In: Silicon in Agriculture. Datnoff LE, Snyder GH, Korndorfer GH (ed), Elseveir Science, The Netherlands.
Nakata Y, Ueno M, Kihara J, Ichii M, Taketa S, Arase S. 2008. Rice blast disease and susceptibility to pests in a silicon uptake-deficient mutant. Crop Protec
27: 865-868.
Nolla RJF, Korndörfer GH, Silva TRB. 2012. Effect of silicon on drought tolerance of upland rice. J Food Agric Environ 10: 269-272.
Oliveira LA. 2009. Silicon in bean and rice plants: absorption, transport, redistribution, and tolerance to cadmium. [PhD. Thesis] Piracicaba, Escola Superior
de Agricultura Luiz Queiroz: p. 1-157.
Ou SH. 1985. Rice diseases (Second ed.). Commonwealth Mycological Institute, Kew, England.
Pereira HS, Korndörfer GH, Moura WF, Corrêa GF. 2003. Extractors of available silicon in slags and fertilizers. Revista Brasileira de Ciência do Solo 27:
265-274.
Pereira TS, Lobato AKS, Tan DKY, Costa DV, Uchôa EB, Ferreira RN, Pereira ES, Ávila FW, Marques DJ, Guedes EMS. 2012. Positive interference of
silicon on water relations, nitrogen metabolism, and osmotic adjustment in two pepper (Capsicum annuum) cultivars under water deficit. Australian J
Crop Sci. paper in press.
Rodrigues FA, Datnoff LE, Korndorfer GH, Seebold KW, Rush MC. 2001. Effect of silicon and host resistance on sheath blight development in rice. Plant Dis
85:827-832.
Rodrigues FA, Datnoff LE. 2005. Silicon and rice disease management. Fitopatologia Brasileira 30(5): 457-469.
Saddler GS. 2005. Management of bacterial wilt disease. In: Bacterial wilt Disease and Ralstonia solanacearum Species Complex. Allen CP, Prior P, Hayward
AC (ed). The APS Press, St. Paul, MN, USA.
Savant N, Snyder G, Datnoff L. 1996. Silicon management and sustainable rice production. Advances Agron 58: 151-199.
Savvas D, Manos G, Kotsiras A, Souvaliotis S. 2002. Effects of silicon and nutrient-induced salinity on yield, flower quality and nutrient uptake of gerbera
grown in a closed hydroponic system. J Applied Botany 76:153-158.
Seebold KW, Datnoff LE, Correa-Victoria FJ, Kucharek TA, Snyder GH. 2000. Effect of silicon rate and host resistance on blast, scald, and yield of upland
rice. Plant Dis 84:871-876.
Seebold KW, Datnoff LE, Correa-Victoria FJ, Kucharek TA, Snyder GH. 2004. Effects of silicon and fungicides at full and reduced rates on the control of leaf
and neck blast in upland rice. Plant Dis 88:253-258.
Seebold KW. 1998. The Influence of Silicon Fertilization on the Development and Control of Blast, Caused by Magnaporthe Grisea (Herbert) Barr, in Upland
Rice (Doctoral Thesis dissertation). University of Florida.
84
Sci. Agri. 8 (2), 2014: 80-85
Silva ON, Lobato AKS, Martins Filho AP, Lemos RP, Pinho JM, Medeiros MBCL, Cardoso MS, Ávila FW, Costa RCL, Oliveira Neto CF, Santos Filho BG,
Andrade IP. 2012. Silicon contributes to increase chlorophyll and this response is modulated by leaf water potential in two tomato cultivars exposed
to water deficiency. Plant Soil Environ. paper is press.
Silva VL, Lopes CA. 1995. Populações epifíticas de Pseudomonas syringae pv. tomato em cultivo comercial de tomateiro industrial. Fitopatologia Brasileira
20:179-183.
Takahashi E, Ma JF, Miyake Y. 1990. The possibility of silicon as an essential element for higher plants. Comments Agric Food Chem 2: 99–122.
Wang H, Li C, Liang Y. 2001. Agricultural utilization of silicon in China. Studies Plant Sci 8: 343-358.
Winslow MD. 1992. Silicon, disease resistance, and yield of rice genotypes under upland cultural conditions. Crop Sci 32(5): 1208-1213.
Yabuuchi E, Kosako Y, Yano I, Hotta H, Nishiuchi Y. 1995. Transfer of two Burkholderia and an Alcaligenes species to Ralstonia gen. nov: Proposal of
Ralstonia picketii (Ralston, Palleroni and Doudoroff 1973) comb. nov, Ralstonia solanacearum (Smith 1896) comb. nov. and Ralstonia eutropha
(Davis 1969) comb. nov. Microbiol Immunol 39: 897–904.
Yanar Y, Yanar D, Gebologlu N. 2011. Control of powdery mildew (Leveillula taurica) on tomato by foliar sprays of liquid potassium silicate. African J
Biotec 10:3121-3123.
Zellner W, Frantz J, Leisner S. 2011. Silicon delays Tobacco ringspot virus systemic symptoms in Nicotiana tabacum. J Plant Physiol 168: 1866-1869.
85