TITLE:
Exogenous Vitamin K3 and Peroxides Can Alleviate Hypoxia in Bean Seedlings (Phaseolus vulgaris L.)
AUTHORS:
C. B. Rajashekar, Jinmin Fu, Anju Giri
KEYWORDS:
Hypoxia, Vitamin K3, Menadione, Peroxides, Beans
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.5 No.22,
November
18,
2014
ABSTRACT:
Oxygen limiting conditions are a common occurrence in root zones of most
crop plants and can adversely affect nearly all aspects of plant growth and
development including its survival. The objective of this study was to
determine the effectiveness of a novel redox cycling agent, vitamin K3,
and various peroxides including hydrogen peroxide, calcium peroxide and
magnesium peroxide in alleviating the effects of hypoxia in bean seedlings
grown in nutrient culture. All the anti-hypoxic agents including vitamin K3 had a positive impact on the overall growth of bean seedlings under hypoxic
conditions, but their responses were variable depending on the concentration.
With regard to shoot growth, vitamin K3 (5 μM) increased the leaf
area significantly, by more than 58% over the hypoxic control plants and
produced the highest stem fresh weight similar to calcium peroxide (20 μM) and
magnesium peroxide (10 μM). In addition, the use of vitamin K3 resulted in the highest accumulation of chlorophyll (chla + chlb) in the leaves,
an increase of nearly two-fold over the hypoxic control plants. Furthermore
under hypoxia, calcium peroxide (20 μM) and magnesium peroxide (10 μM) produced
the highest leaf biomass (FW) followed by vitamin K3. Vitamin K3 (1 μM) also favored root growth in bean seedlings under hypoxia; it produced
the largest increase in root length and root biomass (DW) similar to calcium
peroxide and magnesium peroxide. Based on the overall shoot and root growth
response of bean seedlings to various anti-hypoxic substances under hypoxic
conditions, calcium peroxide, magnesium peroxide and vitamin K3 performed
better than hydrogen peroxide. These findings show that vitamin K3 and peroxide salts are effective in alleviating hypoxic stress in bean
seedlings and also, further highlight their potential for dealing with hypoxia
in wide ranging situations.