Screening Rape (Brassica Campestris) Varieties Of Aluminum-resistance In The Laboratory And Effects Of Al³⁺ Stress On Rape Seedling Growth

Brassica campestrisis one important and oil crops,there are the main rape production area in the middle and lower reaches of the Yangtze River,where the soil is mostly acidic.So study on the A1³⁺ stress to rape and the screening for the aluminum-resistance of Brassica campestris L.is great significance.This study through the ten rapeseed varieties under the acid-aluminum treatment with different concentration comes out the main following result:1.Receive the sequence of the ten anti-aluminum rapeseed varieties with fuzzy comprehensive evaluation method.The rapeseed was cultured and put it in the light incubator.The rapeseed was treated by ten concentration of A1³⁺ when it begun to bud..Then mensurated the root length,fresh root weight,dry root weight.It was found that trace A1³⁺(25～100μmol/L)can promote root elongation growth of rape.But the concentration of A1³⁺ is 800 and 1600μmol/L,the rape root was severely inhibitted.There was a positive correlation among in root length,fresh root weight and dry root weight.The relative root length,relative-fresh weight and relative-dry weight were calculated by the indexes A1³⁺ treated ratio the no A1³⁺.Determine the weight of the three indexes though the AHP.Receive the sequence of the ten anti-aluminum rapeseed varieties with fuzzy comprehensive evaluation method.2.A1³⁺ stress affect the physiological characteristics of rape.Through mensurating the concentration of chlorophyll,root activity,Malondialdehyde(MDA),free proline,Peroxidase (POD) and Superoxide dismutase(SOD),we found that the aluminum stress don't affect the concentration of chlorophyll.There are three changes in root activity:increase,decrease and decrease then increase.Increase show the aluminum stress does not impact the absorption of nutrition for rape,fall is opposition,and the third condition show aluminum stresses reduce the absorption of nutrition startly.The rape show the stronger resistance when the A1³⁺ treatment reach a concentration because the rape showed stronger resistance in order to ensure normal growth.The MDA concentration are great difference among all rape varieties,there are two main conditions which contain increase and decrease.First condition mean cell membrane is hurt by A1³⁺ stress, second condition mean the rapeseed have stronger A1³⁺ resistance.The concentration of free proline are all increase as the A1³⁺ concentration in all rape varieties which show the A1³⁺ stress has affected the cell osmoregulation.There are three changes in the POD,as follow:decrease then increase increase then decrease and decrease.The SOD concentration is general fall.It's show that A1³⁺ stress has hurt the normal growth of rape varieties.