Fertilizer application parameters for drip-irrigated peanut based on the fertilizer effect function established from a “3414” field trial

Scientific fertilization is an important technical means of achieving high and stable peanut yields. Using soil testing and formula fertilization, the "3414" optimal regression design was used and included 14 nitrogen (N), phosphorus (P), and potassium (K) fertilization treatments. Ternary quadratic functions of the fertilizer effect were established according to three-season field experiments and the regression analysis of fertilizer-yield function was performed to explore the optimal fertilizer application mode and ratio for peanuts under mulched drip irrigation (MDI), and a suitable fertilizer application system was established. The ternary quadratic equation relating peanut yield (