TITLE:
Vulnerability of Sunflower Germination and Metal Translocation under Heavy Metals Contamination
AUTHORS:
Rumana Sadiq, Nazimah Maqbool, Bader-Un-Nisa, Kauser Parveen, Mumtaz Hussain
KEYWORDS:
Translocation, Germination, Heavy Metals, Contamination, Sunflower
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.10 No.5,
May
23,
2019
ABSTRACT: The germination and metal translocation ability of
two sunflower seedlings were compared to identify the cultivar differences
towards metal contamination at juvenile
stage. The heavy metal treatments include:
0, 50, 100, 150 and 200 mM Ni, Cd and Pb applied in sand filled pots to
Hysun-33 and FH-533 sunflower. The highest germination percentage (79%) and
vigor index were recorded for Hysun-33 with no heavy metal treatment. Pb and Cd
treatments reduced the growth attributes of 20 days old seedlings of both the
cultivars. The Ni translocation effectively enhanced the shoot and root biomass
of Hysun-33. The high concentration of 150 and 200 mM Cd and Pb drastically reduced
Mn and K contents, vigor, length and biomass of two sunflower cultivars. Among
three of the heavy metals, Cd was found more toxic than Pb and Ni. Roots of 20
days old seedlings of Hysun-33 were able to hold more Cd metal and stop its
translocation to epigenous parts. Although 150 and 200 mM Ni effects the
germination and vigor of sunflower cultivars more than 50 and 100 mM Ni, it is
found less toxic in comparison to Cd and Pb. The Cd accumulation in roots
suggests that it is physiologically most
active sink for Cd metal while epigenous parts of sunflower cultivars are sink for Pb and Ni metal as shoot of sunflower cultivars accumulates high
contents of Pb and Ni.