Phosphorus, Sulphur and Arsenic Assimilation by Rice Genotypes

Plants as well as the varieties of the same plant differ widely in their ability to absorb nutrient/ pollutants from soil even under the same soil fertility level. The present investigation was undertaken to study the varietal influence on the uptake and distribution of phosphorus, sulphur and arsenic in different parts of rice plant. Eight rice genotypes most prevalently grown in new alluvial zone of West Bengal were selected from each of the three categories: (1) high yielding, (2) indigenous aromatic, and (3) indigenous non-aromatic. Among three groups of rice genotype indigenous, aromatic rice group maintained the highest available phosphorus, sulphur and arsenic in soil, while the least in high-yielding group. Considering yields, arsenic concentration and arsenic uptake by rice grain and straw, Kanakchur among the indigenous aromatic rice group and IET 5656 among the high-yielding group were the most promising varieties in the arsenic-contaminated area. The highest transfer coefficients of phosphorus, sulphur and arsenic from soil to root were found in high-yielding rice varieties and the lowest in indigenous aromatic varieties, while from root to shoot the highest transfer coefficients were found in indigenous aromatic rice and the least in high-yielding rice varieties. Soil arsenic had a significant negative correlation (r = -0.32**) with soil phosphorus. Grain arsenic content was significantly negatively correlated with root phosphorus content (r = -0.25*). Thus, genotype had a definite role in the uptake and distribution of phosphorus, sulphur and arsenic content in various parts of rice plant.