Available Silica for Rice in the Lower North Region

Abstract

 Silica is not considered as an essential nutrient for general plant growth.  even though it is a beneficial nutrient for rice, which enhance to pest resistance, erected leaves, anti-lodging and also phosphorus absorption.  Assessment of available soil silica for rice were conducted in the lower north region namely Phitsanulok, Phichit, Petchabun, Sukhothai and Tak provinces.  five hundred and seventy five whole rices plant samples at maturity stage were collected from upland,  rainfed, lowland and irrigated rice as well as soil samples.  Crude silica content in rice straws were analysed as the indicators.  The results showed that 70-80% of the whole rice samples assessed was in the range of very low to low soil available silica except upland rice was in the range of deficiency to very low.