Effect of Nitrogen Levels on Quality of Cucumber in Solar Greenhouse

Effect of nitrogen levels on quality of cucumber in solar-greenhouse was studied. The result showed that the dry matters of cucumber fruits were about 4%～5%, and no obvious difference among different varieties was observed. The dry matters increased as nitrogen increased. As the nitrogen levels ascended, the dissolved sugar and vC contents descended. In the range of 0～40 kg/667 m~2, protein and amino acid contents increased gradually. When more than 40 kg/667 m~2 nitrogen was supplied, most of them decreased. Glutamic acid (GLU) content was the highest amino acid in cucumber fruit, therefore it was an important factor of cucumber quality. Most mineral element contents of treatmentⅡ or Ⅲ was the highest.Under same nitrogen level, Jinlu 3 had the highest content of sugar, but no obvious difference of amino acids among different varieties was observed. Protein and vC content of Xintaimici was the hightest under lower nitrogen levels, while those of Jinlu 3 was the highest under higher nitrogen levels.