Abstract:

Beni Madonna variety experienced tree vigor decline（characterized by reduced leaf size and root rot）due to high flowering intensity，substantial fruit set，and prolonged fruiting periods，significantly compromising yield and quality. To address this issue，based on the growth characteristics of Beni Madonna，two fertilization strategies for enhancing tree vigor and improving quality were implemented in 2023 within the main production area of Taizhou City，Zhejiang Province：Treatment 1 aimed to enhance tree vigor；Treatment 2 aimed to improve fruit quality；traditional fertilization serves as the control group. The results demonstrated that implementing the “small amounts，multiple applications” fertilization approach using an integrated water-fertilizer system significantly outperformed traditional centralized fertilization，effectively addressing tree vigor decline and enhancing citrus quality in Beni Madonna variety. The vigor-enhancing treatment increased spring shoot length and leaf area by 87.73% and 55.79%， respectively， compared with the control，while the quality-enhancing treatment increased root volume by 90.91%. The high-quality fruit rates under both treatments rose by 17.12 and 13.60 percentage points， respectively，with soluble solids content in fruits increasing by 0.44 and 0.80 percentage points，albeit at the expense of lower large fruit rates. In conclusion，the two fertilization treatments employed in this study markedly surpass conventional centralized fertilization methods in promoting new shoot growth，strengthening root development，and improving fruit quality.

Key words: citrus, Beni Madonna, nutritional management, fertilizer, tree vigor, quality improvement