Effect Of Application Of Mixed Chemical Fertilizer And Different Composts On Growth Of Pepper And Oilseed Rape And Soil Nitrogen Supply

Pot and field experiments were carried out to study effect of application of mixed chemical fertilizer and different composts on growth,yields,nitrogen uptake of crop,soil mineral nitrogen,soil microbial biomass carbon and nitrogen and microbial diversity. Rapeseed cake compost,pig manure compost,Chinese medicinal herb residue compost and chicken manure compost were separately mixed with chemical fertilizers(nitrogen, phosphorus and potassium).The results obtained are listed as follows.1.Yields of field pepper,field oilseed rape and pot oilseed rape were increased by 58.8%,44.5%and 45.6%respectively in the application of the four kinds of organic-inorganic mixed fertilizers compared with CK(no nitrogen fertilizers applied) and they were also increased by 10.2%,18.6%and 23.1%,respectively,compared with the treatments of chemical fertilizer alone.This demonstrates that the four kinds of the organic-inorganic mixed fertilizers can have a better effect on the growth of crops than chemical fertilizer.2.Nitrogen taken up by crops in the application of the organic-inorganic mixed fertilizers were 204.1%,29.7%and 128.2%higher than those of CK,respectively,and 8.2%,7.3%and 19.3%higher than those of chemical fertilizer alone respectively;Nitrogen recovery rates in the application of the organic-inorganic mixed fertilizers were 3.75%. 10.6%and 12.4%higher than those of chemical fertilizer alone respectively.Therefore,all organic-inorganic mixed fertilizer treatments could improve nitrogen uptake and nitrogen recovery rates.3.The soil mineral N of the treatments applied with the organic-inorganic mixed fertilizers were 128.5%,35.0%and 159.7%higher than those of CK,respectively,and 26.8%higher than those of chemical fertilizer alone.Thus,the application of the four kinds of organic-inorganic mixed fertilizers could maintain a good synchronization of soil mineral nitrogen supply with the requirement by crops.4.Application of the four kinds of organic-inorganic mixed fertilizers altered soil bacterial communities and increased soil microbial biomass C and N The changing range of soil microbial biomass C and N in the application of the four kinds of organic-inorganic mixed fertilizers were lager than those of chemical fertilizer alone.The soil microbial biomass C and N of the treatments applied with these organic-inorganic mixed fertilizers were 42.0%and 3.54%higher than those of chemical fertilizer alone respectively.This means higher nitrogen buffering capacity of the soil could be obtained with the application of the four kinds of organic-inorganic mixed ferilizers.Hence,the application of these four kinds of organic-inorganic mixed fertilizers synchronized the soil nitrogen supply well with the requirement by pepper and oilseed rape and thus,greatly improved the soil nitrogen supply.To conclude,the application of four kinds of organic-inorganic mixed fertilizers could improve the soil nitrogen supplying characteristics and synchronize the soil nitrogen supplying process with the requirement by pepper and oilseed rape.More or almost the same yields of pepper and oilseed rape could be obtained in the application of the kinds of organic-inorganic mixed fertilizers as chemical fertilizer application alone.Therefore,the organic-inorganic mixed fertilizers will have a promissing future in the development of sustainable crop production.