[Application of biogas fermentation residue in Ziziphus jujuba cultivation]

With field experiment, this paper studied the effects of applying biogas fermentation residue (dregs and slurry) on jujube growth, its fruit quality, and soil fertility. The results showed that biogas fermentation residue could enhance the disease-resistance of jujube plant and its fruit, and improve fruit quality and soil fertility. Compared with applying chemical fertilizers (the control), biogas fermentation residue increased the contents of jujube fruit coarse fiber, vitamin C, amino acids, Fe and P by 27.69%, 24.85%, 19.81%, 10.89% and 5.26%, and of soil organic carbon, total nitrogen and mineral nitrogen by 42.65%, 37.61% and 35.26%, respectively. The soil pH was decreased from 8.75 to 8.21. Biogas fermentation residue could also increase the amount of soil microorganisms. The microbial biomass-C and biomass-N were 59.44% and 56.06% higher than the control, respectively. It was suggested that biogas fermentation residue application could bring better economic and environmental benefits for Z. jujuba cultivation, and also, provide a new approach for no-pollution production of jujube.