Effects of lead application on growth and nutrient accumulations in four o'clocks (Mirabilis jalapa L.)

In the present study, effects of Pb application on the accumulation of nutrients (K, Ca, Mg, Fe, Zn, Cu and Mn) and its effects on the growth in M. jalapa were investigated. M. jalapa seedlings were treated with 0, 10, 100 and 1000 mg/L Pb concentrations. Absorbed Pb were not uniformly distributed throughout the plant. Among plant parts, higher Pb accumulation capability determined in roots compared to stems and leaves, exception of 10 mg/L Pb concentration. Growth and development of M. jalapa were adversely affected by Pb toxicity. In general, contents of Fe, Zn, Mn and Mg were decreased by Pb. In roots, Cu contents changed insignificatly at 10 and 100 mg/L concentrations, but decreased significantly at 1000 mg/L concentration. Despite the fact that Cu contents were rised with Pb applications in stems, the content decreased with increasing Pb concentrations in leveas. In root and leaves, Ca contents were decreased. Moreover Ca content in stems was increased in 100 mg/L Pb concentration, then decreased in 1000 mg/L Pb concentration. K contents in all plant parts were differently affected by Pb. As a results, Pb toxicity disturbed the uptake and translocation of nutrients and induced its nutrient imbalance.