SILICATE AS A FERTILIZER EFFECT ON MORPHO-PHYSIO-BIOCHEMICHAL CHARACTERS IN DIFFERENT RICE CULTIVARS UNDER DROUGHT STRESS CONDITION
Abstract
Silicon (Si) has positive effects on crop products. It effects on some physiological processes and, therefore, decreases drought condition. Advantageous effects of Si on rice (Oryza sativa L.) under water deficiency conditions are not clear. The aim of this research was to investigate the effects of applied Si on physio-biochemical characters in rice under drought stress in two cultivars local taroom and shiroodi. Treatments included combinations of (1) two types of Si application, potassium silicate and calcium silicate, (2) water stress (0.050 MPa or 0.025 MPa soil water potential values), and (3) two cultivars: shiroodi and local taroom), with three replications. Under water deficiency conditions, antioxidant enzymes activity, cellulose, gel consistency percentage and proline content increased. And also, after silicon treatment in rice some morphological characters such as height of plant, harvest index, grain yield, and some of biochemical characters like carbohydrate, protein, K, total chlorophyll, lignin content was increased. After Si application, leaf blast infection has decreased. There was some significance difference between two cultivars in morphological (plant height, length of Panicle, number of the effective tillers per hill, number of panicle in plant, Flag leaf chlorophyll, Harvest index) and biochemical characters (carbohydrate, lignin, protein, Fe, Na, K, Fe content). This result could be indicative of stress tolerance after Si treatment in rice. Combination effect of drought stress on two studied cultivars didn’t show any significant difference between them, and therefore this result proposed that both cultivars can be used in parts of the country with water shortage stress.