As a characteristic cash crop in Yunnan Province, China, Arabica coffee ranks first in the country in terms of cultivation area and production, but has always suffered from poor soil nutrient management and a lack of scientific basis for fertilization. It is not clear how to improve the soil microecological environment using split-reduced drip fertigation at different reproductive stages of Arabica coffee to improve bean yield and quality. Therefore, a two-year (2020–2022) field experiment was conducted on 5-year-old Arabica coffee trees in a dry-hot region with five split-drip fertigation patterns, F450, F600, F750, F900 and F1050. Using the local conventional fertilization (Fertilizer of 900 kg ha−1 year−1 only in berry expansion, and no fertilization in early flowering and berry ripening) as the control (CK). The effects of different fertilization modes on soil microecological environment, bean yield, nutritional quality and characteristic flavor were studied, and a comprehensive benefit evaluation model to assess bean yield and nutritional quality under different fertilization modes was established. The results showed that F900 significantly increased soil nitrate nitrogen, available phosphorus, available potassium, microbial population and enzyme activities at early flowering and berry ripening stages compared to CK, while F900 reduced soil nitrate nitrogen, available phosphorus and available potassium but increased soil enzyme activity and microbial population at the berry expansion stage. Compared with CK, F450 decreased bean yield, caffeine and chlorogenic acid content by 31.83 %, 23.73 % and 13.48 %, respectively, while F750 increased two-year average yield, raw bean fat, caffeine and chlorogenic acid content by 20.52 %, 12.37 %, 5.48 % and 11.17 %, respectively. The two-year average yield of F600 showed less difference from CK. Marginal yield was positive and then negative with increasing fertilizer application. Dry bean yield decreased at a total fertilizer application of 900 kg ha−1 year−1. Correlation analyses showed a positive correlation between soil microbial environment and nutrient quality of coffee beans, while different correlations were found between nutrients and volatiles at dark and medium roasting levels. Cluster analysis revealed that the relative contents of aldehydes, alcohols, phenols, pyridines, and pyrroles were higher under dark roasted condition, while the relative contents of ketones, esters, acids, and pyrazines were higher under medium roasted condition. Based on the Entropy weight-TOPSIS method, F750 had the highest combined benefits in terms of yield increase and quality improvement, and the total fertilizer application decreased by 16.67 % compared to CK, thus F750 treatment was the most suitable split-drip fertigation strategy for Arabica coffee in the dry-hot region of Yunnan. This study provided a reference for drip fertigation systems of Arabica coffee in dry and hot regions.
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