Cadmium Enrichment Ability And Physiology Of Kiwifruit Under Cadmium Stress And Preliminary Study On Cadmium Reduction Technology In The Soil

Due to kiwi cultivation in Hunan Province had been favored by fruit farmers in recent years,while the serious Cd pollution in our province,it is of great significance to carry out research on Cd accumulation differences in kiwifruit and Cd reduction in polluted parks.This article investigates the current situation of cadmium pollution in the kiwifruit orchards in our province and selected two kiwis with different Cd enrichment capabilities for potted Cd gradient stress experiments.The absorption and operation of Cd by kiwi fruit and the effects of Cd on the growth and physiology of kiwi fruit were analyzed.Later,various regulators were applied to Cd polluted fields of different levels in Hunan,and the effects of conditioners on reducing Cd and improving soil fertility and their effects on kiwi fruit growth and fruit quality were analyzed.It is concluded that:(1)The Cd content of kiwi is directly proportional to the concentration of Cd application.The Cd content and Cd accumulation of each organ of kiwi fruit were ranked as root> stem> leaf> fruit according to size,and the root is the main organ that absorbs and accumulates Cd,cadmium content is greater than 90% in root.The total Cd absorption of ML’ whole plant from the soil is higher than that of JY,the cadmium content of its fruit is lower than that of Jin Yan under the low cadmium pollution environment,but when the soil cadmium content exceeds 20mg/kg,its fruit contains more cadmium than Jin Yan.(2)The growth inhibition of kiwifruit is proportional to the amount of cadmium applied.Jin Yan’s leaf margins withered and rolled up,indicating that his leaves were more poisoned than Miliang No.1.When kiwifruit absorbs more cadmium than its own metabolic capacity,the secretion of enzyme activity and regulators that maintain osmotic pressure is reduced,and the soluble protein and sugar of Jinyan are reduced by 3 times and 1.5 times that of Miliang No.1.In comparison,Jin Yan is more sensitive to cadmium threat,Miliang No.1 is tolerant to cadmium.(3)The application of fulvic acid,phosphate calcium fertilizer and long-acting bacterial fertilizer can effectively reduce the cadmium content in the kiwi orchard soil,the decrease range is 46.7%,32.3%,21.8%,and increase the content of nitrogen,phosphorus and potassium in the soil.Phosphorus-calcium fertilizer was also beneficial to the growth of kiwifruit and the improvement of fruit quality.The soluble solid content of its fruit reached 13%,compared with 7% for the control.(4)Application of calcium fertilizer,calcium fertilizer and Chinese medicinal fertilizer,activated carbon,bacterial fertilizer all have good soil cadmium-reducing effect;activated carbon and bacterial fertilizer,activated carbon and Chinese medicinal fertilizer have increased the organic matter content in the soil;Chinese medicinal fertilizer has significantly improved The content of nitrogen,phosphorus and potassium in the soil,but it has no obvious effect on reducing the absorption of kiwi fruit to cadmium;the treatment of calcium fertilizer with traditional Chinese medicine fertilizer,calcium fertilizer plus bacterial fertilizer,activated carbon,activated carbon plus bacterial fertilizer,activated carbon plus traditional Chinese medicine fertilizer significantly reduced the kiwi fruit The absorption of cadmium,especially after the application of activated carbon,activated carbon plus bacterial fertilizer,the absorption of cadmium by kiwifruit was reduced by 55.6% and 53.7%compared with the control,which had a significant effect on reducing the toxicity of cadmium to kiwifruit.