Application nano fruit tree hole storage brick fertilizer is beneficial to increase the nitrogen utilization of grape plants under subsurface drip irrigation

Purpose: Nitrogen (N) is a key factor that limits plant growth in most terrestrial ecosystems. However, N leaching is still serious. Our study sought to provide theoretical basis for improving N fertilizer efficiency by using nano materials in the cultivation of fruit trees. Methods We invented a new type of nano fruit tree hole storage brick (NFTHSB) by using natural nano-materials, biochar and organic fertilizers, designed a new fertilization strategy-application NFTHSB under subsurface drip irrigation to characterise the effects of NFTHSB addition on grape N absorption at three different treatments [ “CK”, “NFTHSB A (T1)” and “NFTHSB B (T2)” ]. Results Results showed that the pore number and pore size of NFTHSB A (T1) were significantly higher than NFTHSB B (T2). Compared with CK, T1 and T2 significantly increased the accumulation of biomass in different organs of plants, N absorption and 15 N content in the roots, stems and leaves. When the soil depth was 15–30 cm, the NFTHSB increased the soil 15 N content substantially. When the soil depth was 30–45 cm, it reduced the soil 15 N content greatly. It obviously increased the activities of nitrite reductase (NR) and glutamine synthetase (GS) in grape leaves, also the activity of the urease (UR) in soil 30 cm. Conclusion NFTHSBs have special pore structure and adsorption, application NFTHSB could effectively absorb N in soil, reduce N loss, significantly improve plant N utilization rate and soil N residual rate, significantly promote the growth of grape. In this experiment, T1 treatment has the best effect.