Effect of Liquid Sodium Silicate Application Combined with Foliar Spray of Sodium Humate on Leaf Growth, Development and Yield of Rice cv. Huong Thom No1 at Some N Fertilizer Rates

Abstract

An experiment was conducted to study the effect of liquid sodium silicate fertilization in combination with foliar spray of sodium humate on growth, development and grain yield of cv. Huong Thom N^o1 in the 2007 spring and summer season. The experiment was based on constant rates of  60 kg P₂O₅, 60 kg K₂O, but varying levels of  nitrogen, i.e. 60 kg, 90 kg and 120 N kg per hectare and divided into two sets. The second set was fertilized with  75 kg of liquid sodium silicate per hectare as basal application in combination with foliar spray of sodium humate 0.03% at tillering stage. It was found that liquid sodium silicate application combined with sodium humate foliar spray exerted positive effect on growth, development of rice plants, i.e. increase in number of effective tillers, leaf area index, chlorophyll contents, and dry matter and yield components. As a result, actual grain yield, in comparison with the control, increased  by 9 - 12%. In addition, application liquid sodium silicate with sodium humate foliar spray improved host resistance to bacterial leaf blight and higher economic efficiency. In order to reduce fertilizer level and to conserve soil fertility, a rate of  90 kg N 60 kg P₂O₅ + 60 kg K₂O plus liquid sodium silicate at 75kg/ha  per hectare was recommended