Relationship between Silicon Accumulation and Yield Production of Rice

Abstract

The application of silicon to increase plant health, resistance to diseases and insect pests and ability of plant to use high nitrogen rates without lodging is a promising means for crop management to increase yield. The objectives of this study were; 1) to investigate the effects of foliar spray of silicic acid in terms of rate and frequency to quantify silicon
dioxide (SiO2) accumulation in grains and straw and 2) to determine relationship between SiO2 accumulation and yield of Chinat 1 rice. The experiment was undertaken at the Faculty of Agricultural Technology, Rajabhat Maha Sarakham University during February to August 2018. A 4 x 4 factorial experiment was set up in a completely randomized design arrangement of the treatments with three replications. Factor A consisted of four levels of silicic acid (0, 50, 100 and 150 ml/20 L water) and factor B included four levels of spraying frequency (one time at 30 days after emergence (DAE), two times at 30 and 60 DAE, three times at 30, 60 and 75 DAE and four times at 30, 60, 75 and 90 DAE). Data were recorded for grain yield, straw dry weight, and SiO2 accumulation in grains and straw. Applications of silicic acid at the rates of 50, 100 and 150 ml/20 L water had significantly higher SiO2 accumulation in grainsand straw than un-treated control, whereas application of silicic acid for four times at 30, 60, 75 and 90 DAE had significantly higher SiO2 in grains and straw than application if silicic acid for one time at 30 DAE, application of silicic acid for two time at 30 and 60 DAE and application of silicic acid for three time at 30, 60 and 75 DAE. Applications of silicic acid at high rates had higher SiO2 in grains and straw than untreated control and applications at low rates. The higher the frequency of spray, the greater the accumulation of SiO2 in grains and straw. Application of silicic acid for four times at 30, 60, 75 and 90 DAE had the highest accumulation of SiO2 in grains and straw. The interactions between rate and frequency of spray were significant for the accumulation of SiO2 in grains and straw. Positive and significant correlations were observed between accumulation of SiO2 in grains and straw, and grain yield (r = 0.42** and 0.47**, respectively). Therefore, silicic acid spray to increase growth and yield of rice should be sprayed, especially on silicon deficient soils. Keywords: silicic acid, silicon, foliar spray and accumulation