SILICON FERTILIZERS: AGRICULTURAL AND ENVIRONMENTAL IMPACTS - Fertilizers: Components, Uses in Agriculture and Environmental Impacts - page 196

d) poorly understood mechanisms of Si action in the soil-plant system. For this reason,
wrong rates and techniques for application are used;
e) low information about the role and functions of Si in the soil-plant system.

The evolution of any fertilizer generally tracks from raw materials low effective in the
soil-plant system to advanced technology products elaborated on a basis of chemical,
biological, and physical processes and specific mixture with other ingredients. Si fertilizer
advancement has a similar regularity. The future of Si fertilizers seems to be connected with
activated Si-rich natural minerals and synthetic liquid Si-rich substances. In our study, the
broadcast application of 2-4 t ha -1 of Si-rich minerals provided a similar effect as the
application of 5-100 kg of modified mineral-based Si fertilizer (Table 5).
To attain the combination of high efficiency, ecological safety, and low cost is the target
for science and business in regard to Si fertilization.

C ONCLUSION

Silicon fertilization provides the following agronomic and environmental benefits:

1) Si increases crop production and quality;
2) Si increases plant drought and salt tolerance;
3) Si protects plant against diseases, insect and fungi attack;
4) Si promotes restoration of degraded soils and increases soil fertility;
5) Si increases soil resistance to wind and water erosion;
6) Si alleviates Al toxicity in acid soils;
7) Si improves plant P nutrition;
8) Si reduces P, N, and K leaching from cultivated areas;
9) Si reduces the mobility of heavy metals.

The main problem concerning the Si fertilizer implementation in the world is scanty
information being disseminated on the benefits of using Si-rich materials as a fertilizer.

R EFERENCES

Adriano, D. C. (1986). Trace Elements in The Terrestrial Environment. New York, Springer-
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Anderson, D. L. (1991). Soil and leaf nutrient interactions following application of calcium
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Banerjee, A. K., Laya Mimo, M. S., & Vera Vegas, W. J. (2001). Silica gel in organic
synthesis. Russian Chemical Reviews, 70(11), 971-990.
Bazilevich, N. I., (1993). Biological Productivity of North Eurasian Ecosystems . Nayka,
Moscow.
Benavides, M. P., Gallego, S. M., & Tomaro, M. L. (2005). Cadmium toxicity in plants. Braz.
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