Effects of tillage and organic fertilizer substitution of chemical fertilizer on anti-aging properties, photosynthesis and maize yield of maize leaves

Corn is one of the favorite crops in China and is grown in a large area in drought-tolerant areas. Tillage practices and fertilizer management are important for crop growth, and there is a lack of research in this area, especially in places where rainfall is scarce. Therefore, it is of great significance to explore the anti-aging characteristics and photosynthesis characteristics of maize leaves by replacing inorganic fertilizer with organic fertilizer under different tillage methods. From 2022 to 2023, two tillage methods, rotary tillage + subsoiling (R + S), three organic alternative inorganic (P ₁ , P ₂ , P ₃ ) and four control CK treatments were used to measure the POD and SOD enzyme activities, PRO and MDA contents, photosynthesis and yield of maize leaves at different growth stages.The results showed that: (1) With the advancement of the growth period, the P ₁ treatment was optimal under different organic substitution and inorganic application methods, Obviously, R + S farming is superior to traditional R farming. The contents of SOD, POD enzyme and PRO in R + S P ₁ treatment were 41.89%, 56.95% and 15.91% higher than those in CK, and 40.21%, 21.22% and 16.94% higher than those in R P ₁ , respectively, and the MDA content in R + S P ₁ was 38.68% lower than that in CK and 11.37% lower than that in R P ₁ , respectively. When the P1 treatment of R + S was performed, the resulting Pn was 23.73% higher than that of CK and 6.01% higher than that of R P ₁ . After P ₁ treatment with R + S, the Tr was reduced by 24.06% compared with CK and 11.14% lower than that of P1 treatment with R. (2)The yield of rotary tillage and subsoiling (R + S) was always better than that of rotary tillage (R) alone, and Yield was under P1 treatment with organic fertilizer was the highest under rotary tillage and subsoiling (R + S) tillage, with an average of 13663.79kg/hm ² , which yield of the P1 treatment was 6.39% higher than that of the P2 treatment, 7.90% higher than that of the P3 treatment, and 14.67% higher than that of the CK treatment, Compared to rotary tillage (R), the yield obtained by P1 treatment was 2.53% higher.(3)At the grain filling stage, the superoxide dismutase (SOD) activity, peroxidase (POD) activity, proline (PRO) content, net photosynthetic rate (Pn), grain number, ear length and 100-grain weight of maize leaves showed a significant positive correlation with the total yield, but negatively correlated with MDA content, Tr and bald tip length. According to the results of our experiment, it can be seen that the anti-aging enzyme activity of organic fertilizer instead of chemical fertilizer P ₁ treatment under rotary tillage + subsoiling (R + S) tillage treatment is the best, and the photosynthesis ability of maize leaves is the strongest, and the yield is the highest.