Effects Of Concentrated Biogas Slurry Application Combined With Chemical Fertilizers On Rice And Rape Yield And Quality

The wastes disposal in china's large-scale farm of poultry and animals has the common problems as large amount of biogas slurry, high water content, the dissociation of planting and breeding, etc. It makes use of biogas slurry more restricted, as well as causing environmental pollution. Actually, the biogas slurry is a good organic fertilizer, which is rich in available nutrients in the form of N, P, K and other biologically active substances such as amino acids, growth hormone. The purpose of this research is using the waste as a resource by liquid fertilizer for field production. The present study include effective composition and content determination in biogas slurry, and the effects of concentrated biogas slurry application combined with chemical fertilizers on rice and rape yield and quality. The results are as follows:⑴There are amino acid, humic acid and protein in biogas slurry. The amino acid reached 15.10 mg·L^-1, including 7 essential amino acids. 3 hormones also be detected in biogas slurry, they are zeatin (ZT), gibberellins (GA) and indole acetic acid (IAA), but the abscisic acid (ABA) which have the inhibition of plant were not detected. The essential trace elements of Mg, Si, S, Cl, Ca, Fe, Mn, Zn were higher levels, while Cu, As, Cr, Pb, Hg were lower.⑵In a appropriate proportion and mode of fertilization with the concentrated biogas slurry and chemical fertilizers, the rice yield can reach or exceed the level of conventional one. It also promoted plant growth and tillering, enhanced Fe and Zn contents, reduced significantly Pb content, reduced the proportion of amylose in rice, maintained the levels of various amino acids, and improved the quality of rice significantly.⑶The concentrated biogas slurry mixed with chemical fertilizer for rape cultivation can increase the yield by 9.7% than conventional one, and the oil content of rapeseed can reach or excel the demand of the standard for first grade oil. The content of oleic acid and linoleic acid was in a high level for ensuring the quality of rapeseeds.