Phytoremediation potential of common tropical hyperaccumulator plants on tin polluted soils

This study assessed the phytoremediation potentials of common tropical hyperaccumulator plants for their germination, survival, and phytoextraction abilities of Tin from polluted soils. Familiar Nigerian crop specieswhich include Sorghum (Sorghum bicolor (L.) Moench), Wheat (Triticum aestivum L.), Maize (Zea mays L.) of White grain and Yellow grain varieties, as well as three varieties of Tomato (Solanum lycopersicum L.) i.e. Hausa, Ogbomoso and Ijebu, were planted in a greenhouse pot experiment. The soils were contaminated with Tin (II) chloride dihydrate (SnCl2.2H2O) at concentrations of 0.6g, 1.2g, 1.8g and 2.4g per 3kg of soil in each pot. The percentages of germination and survival were measured for each plant, and the plants were later assayed using atomic absorption spectroscopy to determine the Tin phytoextraction prospects by the plants. Sorghum presented the most promising Tin hyperaccumulating potential (11.415 ppm) among the sampled plants. Analysis of variance and Least Square means revealed that the Tin phytoextracting potential were significantly different among the sampled plants. Alternatively, the White grained maize recorded the lowest germination (80%) and survival (52.4%) rates, and Tin phytoextracting potential (8.44 ppm). Furthermore, the Pearson correlation coefficient showed that the percentage survival of the phytoremediator plants had a significantly positive correlation with the amount of Tin phytoextracted (r=0.560*). Sorghum is well adapted and widely cultivated across Nigerian agricultural ecologies, hence, it is necessary to be mindful of the Tin content in sorghum which are grown in zones with high soil Tin amounts to check possible Tin poisoning in humans and animals.