Growth Promotion, Increase of Iron, Potassium and Cell Wall Components following Silicon Application in Rice under Iron Deficiency

Iron deficiency is one of the most important stress reducing crop growth and yields. Silicon is also an essential element in most grasses including rice that may reduces biotic and abiotic stresses. In present study, the interactions of silicon and iron nutrition were studied in rice (Oryza sativa L. cv. Tarem). The plants cultivated in greenhouse under iron treatments of 0, 2 and 10 mg l-1 as a Fe-EDTA (first factor) and silicon treatments of 0 and 1.5 mM sodium silicate (second factor). The experimental design was completely randomized blocks as a factorial experiment. The plants were harvested after 5 weeks. Iron deficiency resulted in reduction of dry mater and height of plants. In addition, cellulose content in shoots and lignin and soluble proteins in roots and shoots decreased, however, potassium content in roots increased due to iron deficiency. On the contrary, silicon application caused significant increase in dry mater and height of plants. Besides, iron and potassium contents increased in iron deficient plants following silicon application. Also, cellulose, lignin, and soluble proteins in roots and shoots and phenolic compounds in shoots enhanced in silicon fed plants. The results indicated that silicon nutrition could ameliorate harmful effects of iron deficiency by increase of iron and potassium contents and increment of cell wall components and phenolic compound