Effects Of Chemical Fertilizer Reduction Combined With Organic Fertilizer On Potato Growth And Soil Chemical Properties

In order to explore the effects of chemical fertilizer reduction combined with organic fertilize on farmland soil environment and potato growth in mountainous areas of southern Ningxia,Qingshu 9 potato variety was used as the experimental material in this experiment.Five treatments(CK was the single application of chemical fertilizer,T1 was the reduction of chemical fertilizer by 20%combined with organic fertilizer,T2 was the reduction of chemical fertilizer by 40%combined with organic fertilizer,T3 was the reduction of chemical fertilizer by 60%combined with organic fertilizer,and T4 was the single application of organic fertilizer)were set to study the changes of soil nutrients,enzyme activities,potato plant physiology,yield and quality of potato tubers after chemical fertilizer reduction combined with organic fertilizer.Theeffects of chemical fertilizer reduction combined with organic fertilizer on farmland soil environment and potato production were preliminarily revealed,which provided theoretical basis and technical support for scientific fertilization of potato in southern Ningxia.The main research results are as follows:1.Chemical fertilizer reduction combined with organic fertilizer had different effects on soil nutrients.After the study on soil nutrients,the soil total nitrogen,total phosphorus,available nutriaents,organic matter and enzyme activities under T3(60%reduction of chemical fertilizer combined with organic fertilizer)treatment were better than those under other treatments.Reducing chemical fertilizer and increasing organic fertilizer can reduce pH,reducing chemical fertilizer 20-60%can improve soil EC value,and can effectively improve soil chemical properties.2.In terms of potato growth,T3(60%reduction of chemical fertilizer combined with organic fertilizer)treatment was beneficial to the growth of potato plant height,leaf area index and dry matter accumulation.Chemical fertilizer reduction between 20-40%was beneficial to the growth of potato stem diameter and promote growth and development.In terms of potato physiology,the leaf membrane permeability under T3(60%reduction of chemical fertilizer combined with organic fertilizer)treatment was lower than that under other treatments,which reduced the contents of MDA and POD,increased the activities of SOD and CAT,soluble sugar and soluble protein content,enhanced stress resistance,and promoted the physiological growth of potato.Proline content was relatively high under T2(40%reduction of chemical fertilizer combined with organic fertilizer)treatment.3.In terms of plant nutrients,the nutrient absorption and nutrient accumulation of potato plants under T3(60%reduction of chemical fertilizer combined with organic fertilizer)treatment were better than those under other treatments.The partial productivity of nitrogen,phosphorus and potassium fertilizers and the partial productivity of mediumenergy fertilizers are also relatively high.4.Among the yield and quality,the yield of T3(60%reduction of chemical fertilizer combined with organic fertilizer)treatment was better than that of other treatments,which was 28114.6 kg.hm-2,and the economic benefit was also good.The reduction of chemical fertilizer by 40%could improve the commodity potato rate,and the application of chemical fertilizer alone could effectively reduce the small potato rate.The vitamin C,crude protein and soluble sugar of tubers treated with T3(60%reduction of chemical fertilizer combined with organic fertilizer)were better than those of other treatments.Total starch is better than other treatments,can improve potato tuber amylose,amylopectin content,improve potato quality.