Cadmium Phytoremediation Potential of Napiergrass Cultivated in Kyushu, Japan

Abstract

Napiergrass (Pennisetum purpureum Schumach), a C 4 tropical species, has been used for forage since it has high dry matter productivity, sustainability over several years in low-altitudinal sites of Kyushu, and little damage from serious pests. Recently, this grass has gained attention due to its potential as a bioethanol feedstock and for phytoremediation. Napiergrass cultivar Wruk Wona was grown as an annual crop in cadmium-(Cd-) contaminated soils under two cutting frequencies. Annual dry matter yield was not affected significantly by cutting frequency, but the concentration and uptake of Cd were higher when cut twice rather than only once, due to high Cd content of the herbage from the second cutting. Therefore, the soil Cd concentration was reduced by 4.6% when managed by cutting twice in a single year of Napiergrass cultivation.

Potential use of Pennisetum purpureum for phytoremediation and bioenergy production: a mini review

“…Besides rapid growth, an ideal phytoremediator must also possess a high tolerance to the pollutants and the ability to degrade or concentrate high levels of pollutants in its biomass (Buhari et al, 2016). As reported by Ishii et al (2015), P. purpureum can withstand several highly contaminated conditions. Liu et al (2009) and Kang et al (2012) also demonstrated that P. purpureum is resistant to media that are contaminated with heavy metals, including soil with a high copper level in a pot trial and in solutions containing stable caesium.…”

“…This is because P. purpureum has the mechanism to tolerate high heavy metal concentrations accumulated in its shoots. For example, from the study by Ishii et al (2015), the cadmium concentration in the soil was reduced by about 4.6% and 2.6% in a single year of P. purpureum cultivation with twice and once cutting, respectively. In addition, cadmiun concentration of 1.47 mg/kg, which is almost equivalent to 15 µM cadmium, in the soil had no observable inhibition on the growth of P. purpureum (Ishii et al, 2015).…”

Evaluation of Tropical Grasses on Mine Revegetation for Herbage Supply to Bali Cattle in Sorowako, South Sulawesi, Indonesia

“…(Ni, Cr and Pb) Mining area is always associated with heavy metals that may be contaminated in the surrounding environments (Boom, 2002). Heavy metals can be contaminated with the dust spreading on every surface in the area because of blasting rocks during mining (Bruce et al, 2003;Onder et al, 2007;Gutiérrez-Ginés et al, 2010;Ishii et al, 2015). Heavy metals can also be increased when the soil and grass samples were taken near the shelter mining waste products (Boom, 2002).…”

“…On the other hand, the utilization of post-mine area as a forage crop land is often associated with low-quality grass and so that this study was aimed to evaluate forage quality of the grasses in the mine revegetation area, in addition with the absorption of heavy metals (Ishii et al, 2015). Considerable high content of heavy metal has been reported as a result of several industrial or waste disposal activities in some regions of the world, which could enter to the food chain through different mechanisms and could accumulate in higher organisms such as human beings (WHO, 2007).…”

Effects of Short-Day and Gibberellic Acid Treatments on Summer Vegetative Propagation of Napier Grass (Pennisetum purpureumSchumach)

“…Napier grass (Pennisetum purpureum Schumach) belongs to a tropical C 4 grass with high dry matter productivity [1,2] and it can elongate its stem internode without phase transition from the vegetative to the reproductive state. Napier grass is now used for multiple purposes, including cut-and-carry fodder for herbivores [3], rotational grazing use [4], and feedstock for bioenergy production [5] and for phytoremediation [6] in the Kyushu area of Japan. Napier grass rarely produces viable seed and thus is commonly propagated vegetatively using stem cuttings and rooted tillers [1,7,8].…”