Effect of lead contamination of maize seed on its biological properties

Abstract

Effect of treatment of seed with various lead concentrations (0, 10-5, 10-4, 10-3, and 10-2 mol/dm3) on accumulation and distribution of lead (Pb) in seedling, seed germination, seedling growth, and mobilization of mineral matter during seed germination was investigated. Content of Pb in the root and the shoot indicates that seeds imbibed in solutions of various Pb concentrations took up Pb intensively. Content of Pb in the root and the shoot increased with increase of Pb concentration and it was much larger in the root than in the shoot. Contrary to this, the accumulation coefficient was greater in the shoot than in the root. Treatment of seed with Pb did not significantly affect its biological properties. Increase of Pb concentration decreased germination ability, germination energy, and percentage of typical seedlings, while increasing the number of atypical seedlings and non-germinated seeds. Contamination of seed by Pb did not affect the dry matter mass and the growth of young plants shoots, while the length of the primary root, the mesocotyl root as well as the root mass at the highest Pb concentration, significantly decreased. Translocation of mobilized mineral matter from the seed during germination and growth of young plants into the root and shoot was specific, depending on elements. Only the implementation of the highest implemented Pb concentration affected mobilization and translocation of some elements. Based on the obtained results, it can be concluded that maize is characterized by significant tolerance to Pb contamination during seed germination and growth of seedlings.Ispitano je dejstvo tretiranja semena kukuruza razlicitim koncentracijama olova (10-5, 10-4, 10-3, 10-2 mol/dm3) na nakupljanje i distribuciju olova (Pb) u klijancu, klijanje semena, porast ponika i mobilizaciju mineralnih materija u toku klijanja. Sadrzaj Pb u korenu i izdanku ponika ukazuje da seme potopljeno u rastvore razlicitih koncentracija Pb intenzivno usvaja Pb. Sadrzaj Pb u korenu i izdanku povecao se sa povecanjem primenjenih koncentracija Pb i bio je znacajno veci u korenu nego u izdanku. Nasuprot tome, koeficijent akumulacije bio je veci u izdanku nego u korenu. Tretiranje semena Pb nije u vecoj meri uticalo na njegova bioloska svojstva. Sa povecanjem koncentracije Pb smanjili su se klijavost semena i udeo tipicnih ponika, a povecao se broj atipicnih ponika i neproklijalih semena. Na masu suve materije i rast izdanka mladih biljaka kontaminacija semena Pb nije ispoljila dejstvo, dok su se duzina primarnog korena, korena mezokotila kao i masa korena znacajno smanjili pri tretiranju semena najvecom koncentra- cijom Pb. Translokacija mobiliziranih mineralnih materija iz semena u toku klijanja i rasta mladih biljka u koren i izdanak bila je specificna, zavisna od elementa. Samo je primena najvece ispitivane koncentracije Pb ispoljila uticaj na mobilizaciju i translokaciju nekih elemenata. Na osnovu dobijenih rezultata moze se zakljuciti da se kukuruz u fazi klijanja semena i porasta ponika odlikuje tolerantnoscu prema kontaminaciji Pb.