Abstract

To compare the effects of different fertilization methods on the fruit quality of Zigui Lane Late navel oranges, especially on fruit greening and sugar loss, a field experiment was conducted in a Zigui Lane Late navel orange orchard in Guiya Village, Jiuanxi Town, Zigui County, Yichang City, Hubei Province. Five treatments were set up in the experiment, namely Treatment 1, Treatment 2, Treatment 3, Treatment 4, and Treatment 5, with 20 replicates for each treatment. The results showed that compared with Treatment 5, the single fruit weight, pulp weight, peel weight, transverse diameter, longitudinal diameter, and fruit shape index of the fruits treated with Treatment 1 did not increase significantly, but the coloring rate increased significantly by 343.50%, the peel hardness and pulp hardness decreased significantly by 13.69% and 13.66% respectively, the soluble solid content did not increase significantly, the titratable acid content did not increase significantly, the total sugar content increased significantly by 9.84%, the solid-acid ratio did not increase significantly, the sugar-acid ratio increased significantly by 9.41%, and the Vc content did not increase significantly. Compared with Treatment 5, the single fruit weight, pulp weight, peel weight, transverse diameter, and longitudinal diameter of the fruits treated with Treatment 2 increased significantly by 23.56%, 20.94%, 21.28%, 7.05%, and 9.59% respectively, the fruit shape index did not increase significantly, the coloring rate increased significantly by 339.79%, the peel hardness and pulp hardness decreased significantly by 15.47% and 6.20% respectively, the soluble solid content, titratable acid content, total sugar, and solid-acid ratio did not increase significantly, the sugar-acid ratio increased significantly by 22.35%, and the protein and Vc content did not increase significantly. Compared with Treatment 5, the single fruit weight, pulp weight, peel weight, transverse diameter, longitudinal diameter, and fruit shape index of the fruits treated with Treatment 3 did not increase significantly, the coloring rate increased significantly by 340.72%, the pulp hardness decreased significantly by 6.62%, the peel hardness, soluble solid content, titratable acid content, total sugar, protein, and Vc content did not increase significantly, the solid-acid ratio and sugar-acid ratio increased significantly by 20.35% and 28.24% respectively. Compared with Treatment 5, the single fruit weight, pulp weight, and transverse diameter of the fruits treated with Treatment 4 increased significantly by 19.30%, 20.00%, and 12.18% respectively, the peel weight and longitudinal diameter did not increase significantly, the fruit shape index decreased significantly by 7.14%, the coloring rate increased significantly by 519.18%, the peel hardness and pulp hardness decreased significantly by 21.30% and 12.93% respectively, the titratable acid content decreased significantly by 12.50%, the protein content did not differ significantly, and the soluble solid content, total sugar, solid-acid ratio, sugar-acid ratio, and Vc content increased significantly by 22.01%, 31.15%, 39.42%, 49.41%, and 20.14% respectively. Therefore, it can be concluded that the fertilization method of Treatment 4 has the most obvious effect on alleviating the greening phenomenon and sugar loss of Zigui Lane Late navel oranges.