Agronomy
College, Sichuan Agricultural University, Cheng Du 611130, China
*E-Mail: ewuwei@sicau.edu.cn
Received August 3, 2012
Houttuynia cordata Thunb. is
a plant enrichment in potassium in plant was reported. Salinity and low
potassium availability are important environmental factors restricting
plant growth and productivity throughout the world. The interactive
effects of salinity and potassium on growth, water content, chlorophyll
content, lipid peroxidation content, ion accumulations and K+/Na+
ratio, and organic accumulations as well as oxidative enzymes were
investigated in Houttuynia cordata Thunb.. Plants of
three-leaf-stage were selected for uniformity, then treated with four
levels of Na+ (50, 100, 200 mmol/L) and K+(0, 0.6, 1.2, 2.4 mmol/L) for
20 days. Plant biomass production, ratio of root and shoot, root
numbers, water content and MDA content significantly declined in the
combined effect of salinity and K+ deprivation, and increased with
salinity. However, salinity in conjunction with K+ deprivation led to
an increase on leaf chlorophyll content, which even increased with
increasing salinity levels. As expected, K+ content in plant was
positive correlated with supplementary K+ concentrations, while Na+ was
well correlated with salinity, especially enhanced by the interactive
effects of salinity and K+ deprivation. Soluble sugar and proline
contents remarkable increased by the highest salinity. SOD activity
also substantial increased by the highest salinity, and increased with
supplementary K+ concentrations. However, elevated CAT and POD
activities were not accompanied with an increase in SOD activity.
Key
words: salinity; potassium; ion contents; organic accumulation;
antioxidant enzymes
