RESPONSE OF MAIZE GENOTYPES TO MANGANESE AND CHROMIUM APPLICATION

Maize is used as staple food in various European countries and it is also used for the production of corn syrups, corn starch and corn ethanol etc. Due to the anthropogenic activities our environment has become polluted. Most of the heavy metals have been eliminated from industrial areas which affect our crop production. The current study was conducted to investigate the accumulation of Mn and Cr in root, stem and leaf along with the effects of metals on photosynthetic pigments in different maize genotypes and investigate that which genotype is used as phytoremediation. Five different maize genotypes (30Y87, 31R88, Neelum, Pak afghoi and White Corn) were selected for research experiment. Different concentrations (0, 0.25M and 0.50M) of Cr and Mn in the form MnCl2 and CrCl3 were added separately and in combined form to access the metal accumulation and photosynthetic parameters. Three replications were carried out for each treatment during research. It was found from results that the Cr and Mn accumulation in roots was high than in stem and leaves. More Cr was accumulated in variety 31R88 and very low accumulation of Cr and Mn was found in Neelum variety. Analysis of variance (ANOVA) and Tukey’s rang test (p ≤ 0.05) were applied as statistical tool among treatment means. ANOVA indicated the differences among five different genotypes and different treatments for all parameters were significant. White corn and Neelum variety were more tolerant and have high phosynthetic pigments under heavy metal treatments. Therefore both varieties can be used as phytoremediation. High photosynthetic pigments were found under treatment 0.25M CrCl3 and low photosynthetic pigments were found under treatment 0.5M MnCl2 + 0.25M CrCl3 and treatment 0.5M MnCl2 + 0.50M CrCl3. High metal accumulation was found in stem while low metal accumulation was found in roots (stem>leaves>roots). It was concluded from our study that the heavy metals caused adverse effects on normal growth of maize however it was also found that the maize crop plants may be used for the remediation of heavy metals from soils. It was also concluded that the ability of accumulation of Cr and Mn by maize genotypes depends upon the genetic behavior of plant species.