Plant Scientists Now Paying Attention To Silicon's Role

Silicon, of quintessential importance to semiconductors, is considered unessential for plant function. Nevertheless, the element is absorbed as Si(OH)4 from soil in amounts several times higher than those of other essential macronutrients in certain plant species: For example, the uptake of silicon in rice is about 108% greater than the uptake of nitrogen.

Silicon can benefit plant growth through greater yields (rice and cucumber) or sugar content (sugarcane). Silicon also can be very useful when these plants are under stress.

The element may enhance soil fertility, improve soil physical properties, improve disease and pest resistance, increase photosynthesis, regulate evapotranspiration, increase tolerance to toxic elements such as iron and manganese and reduce frost damage.

"Until now, this element has always befuddled people because plant nutritionists have never considered it essential," said Lawrence Datnoff, professor of plant pathology with the University of Florida's Institute of Food and Agricultural Sciences (UF/IFAS).

Datnoff said new research at the UF/IFAS Everglades Research and Education Center (REC) in Belle Glade shows this element can boost crop yields, reduce the need for expensive fungicides and improve plant resistance to some diseases.

These and other research findings will be discussed by 22 scientists from around the world at the Silicon in Agriculture Conference Sept. 26-30 at the Lago Mar Resort Hotel in Fort Lauderdale.

The program includes speakers from Australia, Brazil, Canada, Colombia, Japan, Korea, Netherlands, New Zealand, Russia, South Africa and the United States.

The conference is being organized by Datnoff, George Snyder, distinguished professor of soil science at the Everglades REC, and Gaspar Korndorfer, professor of soil science at the Universidade Federal de Uberlandia in Brazil. Sponsors include UF/IFAS, the U.S. Department of Agriculture, Calcium Silicate Corp., The PQ Corp., and Albright and Wilson.

Datnoff said silicon has been used successfully in Florida on rice and sugarcane for many years, and it will improve production on other crops ranging from citrus and strawberries to tomatoes and cucurbits.

"For me, as a plant pathologist, to see what silicon does for disease control is just phenomenal," he said. "It doesn't just control one disease, it controls several diseases. You can better manage your fungicide applications, reduce the number of applications or maybe eliminate them altogether."

Datnoff and other researchers at the Everglades REC have demonstrated that the residual effects of this element one year later provide effective disease control comparable to the application of fungicides.

"We also found this element could enhance control of the two most important rice diseases in the world -- blast and sheath blight," he said. "In the case of rice cultivars that are partially resistant to these diseases, the use of silicon makes them completely resistant."

Other faculty at the Everglades REC working with Datnoff and Snyder are Jose Alvarez, professor of agricultural economics, and Christopher Deren, professor of agronomy/breeding. Thomas Kucharek, professor of plant pathology at UF in Gainesville, is also working with the research group.

Soil scientists and plant pathologists from Brazil, Colombia, India and Russia are working with the UF/IFAS research team, as well.

Related website:

Silicon Conference

21-Sep-1999