Abstract:To explore the correlation between physiological and biochemical indexes of spring maize and lodging resistance of stem, nine different spring maize varieties were used as experimental materials, the crushing strength and puncture strength of the third segment of stem base related to lodging resistance of spring maize varieties were measured. The results showed that the crushing strength of different spring maize varieties ranged from 405.77 to 675.43 N/mm2, the maximum crushing strength of Jingnongke728 was 675.43 N/mm2 at mature stage, the minimum crushing strength of Jinnong738 was 405.77 N/mm2 at the bell mouth stage; and the puncture strength ranged from 237.38 to 355.68 N/mm2, the maximum puncture strength of Zhangli178 was 355.68 N/mm2, the minimum value of Jinnong738 was 237.38 N/mm2 in the big bell mouth stage. There was a significant positive correlation between the content of soluble sugar and the crushing strength, the correlation coefficient was 0.885; there was a significant positive correlation between soluble protein and crushing strength, the correlation coefficient was 0.926; there was a significant positive correlation between lignin content and crushing strength and puncture strength at bell mouth stage and spinning stage, the correlation coefficients were 0.875 and 0.992, respectively; there was a significant positive correlation between the activity of phenylalanine ammonia lyase and crushing strength and puncture strength at the bell mouth stage and silking stage, the correlation coefficients at silking stage were 0.971 and 0.833, respectively; there was a significant negative correlation between MDA content and crushing strength and puncture intensity, the correlation coefficients at mature stage were -0.954 and -0.831, respectively; there was a significant positive correlation between proline content and crushing strength at bell mouth stage and silking stage, the correlation coefficients were 0.885 and 0.900, there was a very significant positive correlation between the puncture intensity and the big bell mouth stage, the correlation coefficient was 0.907. The content of soluble sugar, soluble protein, phenylalanine ammonia lyase, lignin and proline of Jingnongke728 and Zhangli178 were higher than other varieties, and the content of malondialdehyde was lower than other varieties, so the lodging resistance was stronger and better than other varieties.