Study On Chemical Fertilizer And Pesticide Reducing Technology In Pepper In Suihua City Of Heilongjiang

Pepper is one of the main economic crops in Suihua,but the unreasonable application of chemical fertilizers and pesticides in pepper cultivation is the main reasons for soil hardening,soil acidification,low crop yield,poor quality,pesticide residues,pathogen resistance and many other problems.Pepper blight is a common disease in pepper cultivation.When the disease is serious,the production can be reduced more than 50%.In this study,the experiments were conducted in Xinnuo vegetable planting cooperative in Beilin district of Suihua city,Heilongjiang Province.On the basis of detecting the residual nitrate nitrogen content in the soil,the amount of quick-acting nitrogen fertilizer was reduced by introducing slow-release fertilizer MEISTER LP70 and applying it in combination with chemical fertilizers.The resistance of cultivars of pepper and fungicides to blight disease were also studied.The results of this study will lay a foundation for the reduction of fertilizer and pesticide in pepper cultivation in Suihua.The results are as follows:（1）The nitrogen dissolution of slow-release fertilizer MEISTER LP70 showed a s-shaped curve,which began to dissolve on the 15th day after application,and the dissolution amount gradually increased from the 15th day to the 75th day,and then the dissolution efficiency tended to be flat,and all nitrogen was dissolved at the 140th day.（2）In the field and pot experiments,there were 4 treatments:conventional fertilization,formula fertilization,slow-release fertilizer MEISTER LP70 fertilization and slow-release fertilizer MEISTER LP70 combined with formula and reduced amount fertilization.The effects of slow-release fertilizer and nitrogen fertilizer on the growth and yield of pepper were studied.In the field experiment,the amount of available nitrogen fertilizer applied in the treatment of slow-release fertilizer constant fertilization was 10.0%less than that of conventional fertilization.The treatment of formula fertilization and slow-release fertilizer MEISTER LP70 combined with formula and reduced amount fertilization was 51.4%and 60.0%less than that of conventional fertilization respectively.In the pot experiment,the treatment of slow-release fertilizer MEISTER LP70fertilization and formula fertilization was 10.3%and 52.9%less than that of conventional fertilization,the treatment of slow-release fertilizer MEISTER LP70 combined with formula and reduced amount fertilization was 60.3%less than that of conventional fertilization.No matter in the field experiment or the pot experiment,the application of slow-release fertilizer MEISTER LP70combined with the measures of quick-acting nitrogen reduction fertilization can meet the growth and development needs of pepper and have no adverse effect on the growth and yield of pepper.（3）The resistance of 23 cultivars to pepper blight in suihua region was significantly different.There were 6 cultivars with high resistance,which were hemp pepper,zhenyan 958,kenfeng 201,ruili horn,snail pepper and jinguan 1011,accounting for 26.1%of the tested varieties;8 resistant cultivars,accounting for 34.8%;4 middle resistant cultivars,accounting for 17.4%.5 susceptible cultivars,accounting for 21.7%.（4）14 fungicides were screened and their toxicity was determined.Among them,80%mancozeb wettable powder+10%fluorothiazolpidone disperse oil suspension emulsion,60%pyrazole·dixon water-dispersing granule,25%wettable powder of frosty urea cyanide,18.7%enyl pyrazolide water dispersing granule,29%pyrazine pyrimidylate suspension agent have a good inhibition effect and a relatively low EC₅₀ value,the EC₅₀ values were 0.1973 g/m L,1.0133 g/m L,19.4046 g/m L,19.4130 g/m L and 19.6032 g/m L respectively.These 5 fungicides were selected for further field experiments.（5）The control effect of five fungicides applied alone in the field on pepper blight was higher than 80%,and the control effect was better.The efficacy of salicylic acid（SA）combined with 5 fungicides on field control of pepper blight was higher than that of fugicide alone.Salicylic acid（SA）combined with fungicide dose by half,80%mancozeb wettable powder+10%fluorothiazolpidone disperse oil suspension emulsion and 60%pyrazole polyram water dispersible granule has the control effect of 90.7%and 89.3%respectively,higher than that of single pesticide processing control effect.However,the efficacy of the other 3 fungicides was lower than that of the single application of pesticides.The effects of single application of pesticide and salicylic acid combined pesticide on the growth and yield of pepper were not significant.