Effects of Oxalic Acid on Physiological-biochemical Traits of Cold Temperate Larix gmelinii Seedlings under Soil Nutrient Deficiency

Organic acids obviously affect plant survival and growth under soil nutrient deficiency condition. Variable proportion A(1) and C horizon mixed cold temperate brown coniferous forest soils was applied to make soil nutrient deficiency condition, and then Larix gmelinii seedlings were planted in these soils. On the basis of oxalic acid concentration range of forest litter leacheate at the northeast forest region, oxalic acid solution with different concentration was sprayed on the surface of Larix gmelinii seedlings, and the effects of oxalic acid on physiological-biochemical traits of cold temperate Larix gmelinii seedlings were studied in our experiment. Results showed that the electrical conductivity and MDA content of Larix gmelinii seedlings were decreased with the increase of oxalic acid concentration. Most SOD and POD activity of Larix gmelinii seedlings were increased. 5.0mmol center dot L-1 oxalic acid has significant effects on proline and soluble protein osmotic adjustment substances. And Larix gmelinii seedlings grew well at the concentration of 10.0mmol center dot L-1 oxalic acid.