Effects of organic fertilizer replacement on growth physiological characteristics and yield formation of potato
[Objective]This study aimed to establish a technical and theoretical foundation for eco-friendly potato cultivation in the dry farming regions of central Gansu Province.The research focused on elu-cidating the primary mechanisms underlying the substitution of organic fertilizers for chemical fertilizers con-cerning photosynthetic characteristics and antioxidant enzyme activity.[Method]Four distinct treatments were implemented:sole application of chemical fertilizer(T1),50%substitution of organic fertilizer for chemical fertilizer(T2),25%substitution of organic fertilizer for chemical fertilizer(T3),and a control group without fertilizer(T4).The impact of these treatments on potato growth,photosynthetic physiologi-cal traits,and yield was investigated.[Result]The T2 treatment notably enhanced potato growth.Within the substitution regime,the leaf area index,chlorophyll a,chlorophyll b,and total chlorophyll content signifi-cantly increased by 112.5%,50.82%,82.86%,and 57.59%,respectively,compared to the no-fertilizer treatment T4.Organic fertilizer substitution augmented the superoxide dismutase activity during tuber swell-ing and starch formation stages while reducing malondialdehyde levels.Yields rose by 7.89%to 28.37%compared to T1 and T4 treatments devoid of fertilization.[Conclusion]Through the optimization of the in-terplay among leaf area index,chlorophyll levels,and photosynthetic traits,the T2 treatment with a 50%re-placement ratio of organic fertilizer for chemical fertilizer bolstered antioxidant enzyme activity in leaves,de-layed plant aging,and heightened photosynthetic efficiency and effective dry matter transport,ultimately en-hancing yield.In summary,a 50%substitution of organic fertilizer for chemical fertilizer emerges as the suit-able scientific replacement ratio in this region.