Establishing a Physiology-Yield-Quality Evaluation Model for Optimizing Drip Irrigation on Grape Fields in Extremely Arid Regions

Abstract

HighlightsRegulated deficit irrigation and fertilization ratio were used to test grapes in extremely arid areas.Physiology, yield, and quality indexes of drip irrigation grapes were analyzed accordingly in this study.Single and comprehensive evaluation models were used to evaluate the optimal water and fertilizer treatment.Abstract. Water shortage and chemical fertilizer abuse are important factors restricting grape industry development in Xinjiang. In this study, the physiology, yield and quality indexes of drip irrigation grapes were analyzed, and the water-fertilizer system was properly optimized by a model of combination of single evaluation methods and comprehensive evaluation methods. Five irrigation schemes and three fertilizer ratios were combined to form 15 treatments in Xinjiang, China. Results showed that irrigation and fertilization had different effects on physiology, yield, and quality indicators of grapes in different growth periods, and each index cannot reach its maximum value under the same treatment. Four single evaluation methods of Principal Component Analysis (PCA), Membership Function Analysis (MFA), Gray Correlation Analysis (GCA), and TOPSIS were used to evaluate grapes of 15 water and fertilizer treatments, but there were 9 treatments with a ranking standard deviation greater than 1.0, which was over 60% of all treatments. Through four comprehensive evaluation methods of Average Value, Borda, Copeland, and Fuzzy Borda, single evaluation results were analyzed, and the standard deviations of 13 treatments ranked 1.0 or below, more than 80% of all treatments, and Average Value comprehensive method had the highest compatibility. Therefore, the combination of Average Value method and four single evaluation methods is an appropriate evaluation model. It was determined that W4F2 was the optimal treatment which was performed regulated deficit irrigation in the berry mature period, the irrigation amount, nitrogen, phosphorus, and potassium fertilizers were sequentially controlled to 694 mm, 235.7, 235.7, and 353.6 kg·ha-1, and its ranking was ranked first under the four comprehensive evaluation methods. This study can provide theoretical guidance for the combined evaluation of water and fertilizer use of drip irrigation grapes in extremely arid regions. Keywords: Comprehensive model evaluation, Extremely arid regions, Drip irrigation grapes, Physiology-yield-quality effects, Single method evaluation.