Zhao Ying, Gong Yanchen, Li Yun, Xin Hua, Chi Ruiping, Chen Yanling
College of Resources and Environment Science, Qingdao Agricultural University, Qingdao, Shandong, China.
Agricultural Technology Extension Service Center, Laixi Agriculture and Rural Bureau, Qingdao, China.
Front Plant Sci. 2025 Jun 13;16:1590774. doi: 10.3389/fpls.2025.1590774. eCollection 2025.
The coordinated management of water and fertilizer is essential for improving vegetable yield and quality. However, its role in connecting quality with the anatomical structure of the phloem and xylem in carrots remains unclear.
This study involved a two-year field trial with four different water and fertilizer treatments: farmer practices (FP), an optimized water and fertilizer system (OPT), 30% organic substitution with compressed peanut shells (PS), and 30% organic substitution with Pleurotus ostreatus residue (M) combined with water and fertilizer optimization.
Compared with the FP treatment, the OPT, PS, and M treatments increased both yield and quality. Flavor quality increased by 17.51%, 13.04%, and 15.05%, and nutritional quality increased by 11.04%, 8.12%, and 17.35% in the upper, middle, and lower segments, respectively, in the OPT treatment. In contrast, the organic substitution treatments (average of PS and M) resulted in even greater improvements, with flavor quality increasing by 32.50%, 18.21%, and 38.07%, and nutritional quality increasing by 10.28%, 4.69%, and 25.41%, respectively. In the phloem, flavor and nutritional quality increased by 9.59% and 13.50%, respectively, in the OPT treatment and by 12.35% and 17.69%, respectively, in the organic substitution treatment. In the xylem, flavor and nutritional quality increased by 1.64% and 19.09%, respectively, in the OPT treatment, whereas in the organic substitution treatments, flavor quality increased by 16.89%, and nutritional quality increased by 1.94%. Compared with those in the FP treatment, the phloem parenchyma cell area (Pca) and the proportion of xylem vessels to secondary xylem (Pxv) in the upper segment were 9.17% and 88.40% greater in the OPT treatment, respectively, and 18.44% and 116.22% greater in the organic substitution treatment, respectively. The parameters characterizing Pca and Pxv in the upper segment, along with Pca in the lower segment, were positively correlated with flavor and nutritional quality, whereas the xylem vessel area (Xva) and diameter (Xvd) were negatively correlated.
In conclusion, the coordinated management of water, organic, and inorganic fertilizers improves flavor and nutritional quality across the upper, middle, and lower segments, as well as in the phloem and xylem. The superior phloem parenchyma cell area and xylem vessel proportion in the upper segment may serve as physiological traits in breeding carrots for quality improvement.
水肥协同管理对于提高蔬菜产量和品质至关重要。然而，其在胡萝卜品质与韧皮部和木质部解剖结构之间的联系方面所起的作用仍不清楚。
本研究进行了为期两年的田间试验，设置了四种不同的水肥处理：农民常规做法（FP）、优化水肥系统（OPT）、用压缩花生壳进行30%有机替代（PS）以及用水肥优化结合平菇菌渣进行30%有机替代（M）。
与FP处理相比，OPT、PS和M处理均提高了产量和品质。在OPT处理中，上、中、下段的风味品质分别提高了17.51%、13.04%和15.05%，营养品质分别提高了11.04%、8.12%和17.35%。相比之下，有机替代处理（PS和M的平均值）带来了更大的改善，风味品质分别提高了32.50%、18.21%和38.07%，营养品质分别提高了10.28%、4.69%和25.41%。在韧皮部，OPT处理的风味和营养品质分别提高了9.59%和13.50%，有机替代处理分别提高了12.35%和17.69%。在木质部，OPT处理的风味和营养品质分别提高了1.64%和19.09%，而在有机替代处理中，风味品质提高了16.89%，营养品质提高了1.94%。与FP处理相比，OPT处理上段的韧皮薄壁细胞面积（Pca）和木质部导管占次生木质部的比例（Pxv）分别增加了9.17%和88.40%，有机替代处理分别增加了18.44%和116.22%。上段表征Pca和Pxv以及下段Pca的参数与风味和营养品质呈正相关，而木质部导管面积（Xva）和直径（Xvd）呈负相关。
总之，水、有机和无机肥料的协同管理提高了胡萝卜上、中、下段以及韧皮部和木质部的风味和营养品质。上段优越的韧皮薄壁细胞面积和木质部导管比例可作为胡萝卜品质改良育种中的生理性状。
