Determination of amount of irrigation and nitrogen for comprehensive growth of greenhouse cucumber based on multi-level fuzzy evaluation

Abstract

In the northwestern part of China, rational and efficient management of irrigation and nitrogen significantly affects the intensive production of greenhouse cucumbers (Cucumis sativus L). To evaluate the effects of different combinations of water use and nitrogen (N) on yield, quality, and profitability of the greenhouse cucumbers that planted in 2018 Spring, nine combined treatments were applied. Results indicated the optimal irrigation and nitrogen demands for yield, quality and other indicators were different. The irrigation amount significantly affected the yield, and the yield gradually increased with increasing in irrigation. Single fruit weight (SFW) was significantly affected by the amount of irrigation, nitrogen and their interactions, and the higher amounts of N and irrigation were beneficial to the increase of SFW. The partial factor productivity of the applied N (PFP N ) gradually increased with the nitrogen amount decline. Irrigation water use efficiency (IWUE) was closely related to the amount of irrigation. The higher irrigation amount would lead to the lower IWUE. When the amounts of irrigation and nitrogen were at an intermediate level, the content of vitamin C (VC) reached the maximum. As the amount of nitrogen was increased or irrigation was decreased, the Nitrate content (NC) would increase. Free amino acid (FAA) and NC followed a similar variation. When the amounts of irrigation and nitrogen both were at medium levels, the total soluble sugar concentration (TSSC) reached the highest. The multi-level fuzzy evaluation method was used to evaluate different indicators of cucumber. The weights of indicators in the first and second layer were determined by analytic hierarchy process (AHP) and entropy weight method, respectively. Then the fuzzy algorithm was used to comprehensively evaluate all the treatments. The evaluation results show that T4 (irrigation, 1957.6 m 3 /hm 2 ; N, 210 kg/hm 2 ) is the best strategy for greenhouse cucumber irrigation and nitrogen management in the northwestern part of China.

Appropriate supply of irrigation and nitrogen produced higher yields of cherry tomatoes

“…3) Calculation of the combined weight The game theory was adopted to calculate the combined weight based on the obtained objective and subjective weight to minimize the deviation and improve the reliability of the final weight [29] . The following formula obtained the comprehensive coefficient of the objective and subjective weight:…”

Assessing the impact of biochar and nitrogen application on yield, water-nitrogen use efficiency and quality of intercropped maize and soybean

“…To improve efficiency, ensure crop yield, and save costs, it is essential to have scientific guidance on appropriate BC and N fertilizer applications ( Sun et al., 2019 ). At present, mathematical models have been utilized to provide guidance for the application of water and fertilizer in agriculture (He et al., 2021a ; He et al., 2021b ), there has been limited research on mathematical models about BC and N fertilizer coupling. Additionally, current research on the combination of BC and N fertilizer mainly focuses on monoculture, with limited studies on intercropping systems, particularly regarding the comprehensive regulation and analysis of intercropping yield, water, and N utilization.…”

Precision Nitrogen Fertilizer and Irrigation Management for Apple Cultivation Based on a Multilevel Comprehensive Evaluation Method of Yield, Quality, and Profit Indices

“…Many evaluation methods have been used in agriculture, but most of them are single evaluation methods that cannot objectively and subjectively evaluate the growth of the final crops [23][24][25]. The multilevel fuzzy comprehensive evaluation (MFCE) method can effectively combine subjective and objective evaluation results based on fuzzy algorithms and is widely used in many fields [26][27][28]. Therefore, in this study, the objectives were to (1) explore how nitrogen application and irrigation and their interactions affect various indicators in apples; (2) determine the importance of different apple indicators for the comprehensive growth of apples based on subjective and objective evaluations; and (3) determine how coupled nitrogen and irrigation effects influence the comprehensive growth of apples based on the MFCE method and determine the optimal irrigation and nitrogen management rates for apples in the Loess Plateau.…”