11 research outputs found
Activity and localization of lipoxygenase in the ovule of Larix kaempferi (Lamb.) Carr. during megasporogenesis
Improvement of Cerium on Photosynthesis of Maize Seedlings Under a Combination of Potassium Deficiency and Salt Stress
Effects of Cadmium Stress on Root Tip Cells and Some Physiological Indexes in Allium Cepa Var. Agrogarum L.
Allium cepa var. agrogarum L. seedlings grown in nutrient solution were subjected to increasing concentrations
of Cd2+ (0, 1, 10, 100 μM). Variation in tolerance to cadmium toxicity was studied based on chromosome aberrations,
nucleoli structure and reconstruction of root tip cells, Cd accumulation and mineral metabolism, lipid
peroxidation, and changes in the antioxidative defense system (SOD, CAT, POD) in leaves and roots of the
seedlings. Cd induced chromosome aberrations including C-mitoses, chromosome bridges, chromosome fragments
and chromosome stickiness. Cd induced the production of some particles of argyrophilic proteins scattered
in the nuclei and even extruded from the nucleoli into the cytoplasm after a high Cd concentration or prolonged
Cd stress, and nucleolar reconstruction was inhibited. In Cd2+-treated Allium cepa var. agrogarum
plants the metal was largely restricted to the roots; very little of it was transported to aerial parts. Adding Cd2+
to the nutrient solution affected mineral metabolism. For example, at 100 μM Cd it reduced the levels of Mn, Cu
and Zn in roots, bulbs and leaves. Malondialdehyde content in roots and leaves increased with treatment time
and increased concentration of Cd. Antioxidant enzymes appear to play a key role in resistance to Cd under
stress conditions