부산대학교 도서관

Background and Aim: The deep placement (DP) of fertilizers is a key strategy to improve fertilizer-use efficiency in rice production. In this study, we assessed the effect of DP with nitrogen (N), phosphorus (P), and potassium (K) fertilizers on the spatial distribution of root system architecture (RSA) and evaluated the combined effect of DP fertilization and RSA on essential mineral uptake. Methods: A three-year field experiment was conducted using the Akitakomachi rice cultivar with three fertilization treatments: Mix (broadcast), DP1 (one-position-DP at 7 or 10 cm soil depth), and DP2 (two-position-DP at 7 and 15 cm depth). A root box experiment was conducted to quantify the responses of RSA. The root morphological traits were measured in the field and root box experiments. Results: The amount of mineral uptake of N, P, and K, applied as fertilizers, and other minerals such as calcium and magnesium during ripening period, was significantly increased by DP. DP resulted in changing the RSA with greater root surface area and thicker roots (with a diameter of 0.1–0.4 mm) accumulation in deep soil layers at the fertilizer position. Root box experiments also supported root accumulation at localized fertilizer position. Conclusion: DP helped maintain a continuous nutrient supply during ripening by promoting root accumulation at the fertilizer position. The ability of roots to accumulate toward fertilizer can be an effective strategy for creating an ideal RSA for better mineral uptake, which can reduce the fertilizer input required to achieve sustainable rice production. [ABSTRACT FROM AUTHOR]