Effects Of Fertilizers Treatment On Cadmium Accumulation And Growth In Cucumber And Chinese Cabbage Under Cadmium Pollution

With the development of society,the problem of heavy metal pollution becomes more and more serious,which brings about threats to the safety of agricultural products and indirect ly harm to humans' safety.As a commonly used means in agricultural production,rational fertilization can not only improve the soil environment and promote plant growth and development,but also affect the enrichment and migration of cadmium.herein,cucumber and Chinese cabbage were employed as experimental materials by simulating soil Cadmium pollution.The transformation of Cadmium forms in soil,the accumulation of cadmium by cucumber and Chinese cabbage,and the effects of cadmium accumulation on the growth of cucumber and chinese cabbage were investigated via the application of four different fertilizers including organic fertilizer,phosphate fertilizer,microbial bacterial fertilizer and biochar base fertilizer.This provides theoretical basis for safe production of vegetables.The results are as follows:(1)The p H and the content of organic matter in soil decreased with cadmium pollution.The application of commercial organic fertilizer,phosphate fertilizer,microbial fertilizer and biochar base fertilizer could increase the soil p H and the content of organic matter.Beside s,it contributed to the decrease of available cadmium(exchangeable cadmium and carbonate-bound cadmium)for soil.When applied with single fertilizer,biochar base fertilizer,commercial organic fertilizer,phosphate fertilizer and microbial bacterial fertilizer showed the best effect on the reduction of available Cadmium.(2)Biochar base fertilizer could effectively alleviate the Cadmium pollution on cucumber and Chinese cabbage.Meanwhile,the biochar base fertilizer applied was 30g/kg.Besides,the pl ant growth and yield were improved(the content of total cadmium in cucumber and Chinese cabbage was effectively reduced,and the content of soluble sugar,soluble protein and Vc was increased).(3)The compound effect of commercial organic fertilizer,phosphate fertilizer and microbial bacterial fertilizer was better than that of single application.Additionally,the combination of Y3P2J1 and Y3P2J3 showed the best effect on alleviating the harm of cadmium to cucumber.Moreover,the combination of Y3P2J1 and Y3P3J0 presented the best effect on reducing the harm of Cadmium to chinese cabbage.(4)Whether cucumber or chinese is harmed by Cadmium,its malondialdehyde content,free proline,SOD enzyme activity,POD enzyme activity,and CAT enzyme activity incr ease.After applying a certain fertilizer(whether it is fertilizer interaction or Single application of Biochar based fertilizer)can reduce the malondialdehyde content,free proline content,SOD enzyme activity,POD enzyme activity and CAT enzyme activity to a certain extent,but it is still higher than the control of conventional uncontaminated soil.During the growth of cucumber and chinese cabbage,the activities of the three enzymes(SOD,POD,CAT)all increased first and then decreased,and malondialdehyde showed a trend that first increased and then decreased.There is a slight difference on free proline,cucumber have been rised,while chinese cabbage has increased first and then decreased.