Institutional Repository | Satya Wacana Christian University: Pertumbuhan, Kandungan Klorofil, dan Aktivitas Nitrat Reduktase Sorghum bicolor (L.) Moench pada Kondisi Cekaman Krom

Abstract
Chromium (Cr) used in the leather tanning industry and steel production have a
negative impact on the environment. Chromium are toxic to plants. The mains of
this research were to study the effect of chromium to the growth, chlorophyll
content and in vivo nitrate reductase activity of Sorghum bicolor (L) Moench. The
study was conducted by germinating Sorghum bicolor on straw paper tray with
distilled water for 7 days, then acclimated for 12 days in medium sand with
Hoagland (Zayed et al. 1998). Then treated with Hoagland containing Cr(III) (0
mg/kg; 4,5 mg/kg; and 13,6 mg/kg) and Cr(VI) (0 mg/kg; 1,8 mg/kg; and 4,5
mg/kg) for 30 days. Parameters were observed in terms of in vivo nitrate
reductase activity, chlorophyll content, and growth. Chlorophyll content and
nitrate reductase activity were measured by spectrophotometer Shimadzu UV-Vis.
Sorghum bicolor growth decreased more significantly when growing under Cr(VI)
than Cr (III). The largest decline in the dry weight of the badik and UPCA affected
by Cr(VI) 4,5 mg/kg. Cr(VI) 4,5 mg/kg also reduced total chlorophyll 63% on badik
and 72% on UPCA. While nitrate reductase activity on badik and UPCA affected by
Cr(III) 13,6 mg/kg which decreased by 6% and 70%.
Key words: Chromium, Sorghum bicolor, nitrate reductase activity, chlorophyll,
growth