Effects of irrigation amount on growth and nitrogen efficiency of cucumber cultivated in organic substrate

For improving water use efficiency refinement management level of organic substrates culture, with "Biyu2" as material and vinegar residue substrate as cucumbers'culture substrate, four treatments with irrigation amount between 40% and 55% of the maximum mass moisture content of substrate (T1), between 55% and 70% of the maximum mass moisture content of substrate (T2), between 70% and 85% of the maximum mass moisture content of substrate (T3), between 85% and 100% of the maximum mass moisture content of substrate (T4) were conducted and the effect of different irrigation level treatments on growth, dry matter accumulation, photosynthetic capacity, yield, water and production efficiency of nitrogen (N) of cucumber were studied. The results showed that: with irrigation amount increased, the yield of Cucumber increased but the efficiency of water use decreased; T4 had the highest yield but the lowest water use efficiency , and T1 had the lowest yield but the highest water use efficiency; leaf nitrogen content and root nitrogen mass fraction were both not significant difference between T2 , T3 and T4; fruits nitrogen mass fraction under T1 was significantly higher than other treatments, while the stems and leaf nitrogen mass fraction were significantly lower than other treatments; different irrigation levels treatment had no significant effect on nitrogen production efficiency of cucumber in organic substrates culture. Results can provide technical support and basis for water precision management in organic substrate cultivated.