Role of Thermal Exposure in Extraction of Plant Available Silicon from Neutral, Acidic and Alkaline Soils

ABSTRACT

Silicon, the second most abundant element on the Earth crust, is often considered beneficial for plant nutrition. However, plant available fraction of silicon (Si) is hard to find and extract from many types soils. Soil reaction (pH), temperature and plant uptake are some of the major determinants of Si availability affecting its extraction from soil. In this experiment, neutral, acidic and alkaline soils along with plant samples (whole rice plant) have been collected from farmer’s field. Plant samples were processed following existing procedure. Soils are air dried, grinded and passed through a 2 mm pore sieve. Four levels of shaking time (0, 5, 10 and 20 minutes and denoted as S₀, S₅, S₁₀, and S₂₀,respectively) @ 120rpm (round per minute) and four levels of temperatures (room temperature or 25°C, 60°C, 80°C, and 100°C; denoted as T₀, T₆₀, T₈₀ and T₁₀₀, respectively) were employed for preparation of aliquot from soil-water (1:10 ratio) suspension. Acidic and alkaline soils have higher extractable silicon than neutral soil. Combined effect of shaking time and temperature released higher Si values than control, amongst which Si extracted from S₂₀T₁₀₀ treatment is significantly correlated with Si content in rice and have better result for all soils in common.

KEYWORDS:

• Silicon
• rice
• soil pH
• shaking
• temperature
• plant uptake

Acknowledgments

The authors do not have any conflicts of interest and are thankful to Bidhan Chandra Krishi Viswavidyalaya for providing necessary supports during the entire period of experimentation.

Author contributions

Pravat Utpal Acharjee, Swarbinay Mahanta and Prasanta Kumar Patra developed the original idea and the executional procedures. Shrenivas Ashrit assisted in sampling works. Pravat Utpal Acharjee and Swarbinay Mahanta analyzed the samples following the protocol. Pravat Utpal Acharjee, Swarbinay Mahanta, Prasanta Kumar Patra, Debashis Ghosh, Shreya Das, Souvik Roychowdhury, Sandipan Sarkar and Arnisha Mandal abstracted and wrote the manuscript. Pravat Utpal Acharjee and Prasanta Kumar Patra have done statistical analysis and interpretation of data.