Silicon nutrition and distribution in plants of different Thai rice varieties

Abstract

© 2018 Friends Science Publishers. Rice grain yield benefits from silicon (Si) accumulation in sufficient concentration in the plant, but too much Si in the husk and straw can impede their usefulness as biofuel and animal feed. This study consisted of four experiments. The first experiment evaluated genotypic variation in Si distribution in different parts of the rice grain from farmers' fields in northern Thailand, parts of grain to compare tall plant type and semi-dwarf varieties. The result showed that there were significant differences among the rice varieties in Si concentration of their husk and straw, but without clear distinction between the tall and semi-dwarf plant type or between wetland and upland ecotype. The second experiment evaluated Si distribution in different plant parts among 29 Thai rice varieties, and found significant variation in Si concentration among different parts of the rice plant parts, with the husk Si almost twice the straw, and among the rice ecotypes. The third experiment determined the effect of Si fertilizer on Si distribution in a pot experiment on 3 rice varieties with and without of Si application. The fourth experiment evaluated the effect of different growing locations on Si concentration in different plant parts of the 3 rice varieties. These last 2 experiments showed that rice varieties responded differently to Si fertilizer and location in the Si concentration in their husk and straw. Grain yield was significantly correlated with the Si concentration in the husk but not in the straw. The genotype by environment and management interaction effect on Si concentration in the rice husk and straw together with their relationship to grain yield suggested that further investigation of the relationship between husk Si and grain yield. The underlying processes should make Si management for rice production more effective, for the potential energy to be recovered from the husk and straw as well as grain yield.