Growth, yield and element-analysis of rice (Oryza sativa L.), grown in soil amended with fly ash and municipal biosolids

Rice was grown in soil co-amended with coal fly ash (FA) with municipal biosolids (MBS) to study the accumulation of heavy metal (HM) in rice seeds from FA with the co-amendment of MBS. Element-analyses of soil samples, plant-roots and seeds revealed the accumulation of HMs, Fe, Mn, Ni, Co, Zn, Cu and Pb proportionate to the FA doses. For ascertaining some suitable amendment-doses for maximal grain yield with the least accumulation of HMs, principal component analysis (PCA) was carried out with data from three rabi (winter) seasons. With PCA, the variance of performance of FA and MBS together was obtained, 87.25%. It could be concluded that the double amendment levels up to 10 Mg ha−1 FA + 7.5 Mg ha−1 MBS would be the desirable on soil with the accumulation of Pb12 ppb; nonetheless, the toxicity from other HMs was noted at the level 12 mg Mg−1 in rice grains.