Effect of compost on the nitrate phytoremediation by the mung bean plant

Abstract The present study aims to investigate the effect of compost on the nitrate absorption capability of the mung bean plant by employing the phytoremediation method. The examined factors at 7 levels include nitrate alone at concentration levels of 10, 30 and 50 mg/L, nitrate at concentration levels of 10, 30 and 50 mg/l together with compost and control treatment (compost- and nitrate-free soil) along with soil depth at three levels of 0-10, 10-20 and 20-30 cm.The highest wet weights of the plant during the pod setting and maturity stages corresponding to the roots, were estimated as 36.97and 17.69 g in the compost+nitrate treatment at concentration level of 50 mg/L (SCn3), respectively. However, the lowest wet weight during the pod setting stage was recorded in the plant shoot as 4.87 g (control treatment) while it was measured as 6.41 g for the leaf during the maturity stage in the compost+irrigation treatment with a nitrate concentration of 30 mg/l (Scn2). Furthermore, the highest plant’s dry weight (103.3 g) was related to the plant root and irrigation treatment with 50 mg/l nitrate (Sn3) while the lowest one (26.7 g) was associated with the leaf and control treatment. According to the results obtained, during the pod setting stage, the nitrate uptake rate by mung bean root and shoot increased with the increasing compost. Moreover, at high nitrate concentration levels, the effect of compost on the nitrate uptake rate by the mung bean plant was greater and this matter was eventually transferred to the plant shoot.