Comprehensive evaluation of suitable water and fertilizer dosage for drip irrigation grapes in oasis irrigation area

To explore appropriate amount of water and fertiliser for drip irrigation grapes in oasis irrigation area, ten-year-old grapes of "Red Globe Grape" as test materials, four irrigation quotas of 7000（W₁）, 6000（W₂）, 5000（W₃）and 4500 m³/hm²（W₄）, and three fertilization levels of 750（F₁）, 600（F₂）, and 450 kg/hm²（F₃）were set up．Fertilization ratio was 2（N）∶1（P₂O₅）∶2（K₂O） to carry out the large-scale field experiment．Effects of water and fertiliser dosage on physiological growth, yield quality, and water and fertiliser use efficiency of drip irrigation grapes in oasis irrigation area were analysed and evaluated based on principal component analysis．Results showed that suitable water and fertilizer promoted physiological growth of grapes, net photosynthetic rate and maximum photochemical efficiency of PS II with W₁F₂ increased by 0.57% and −0.48% than W₂F₂, and the maximum values of yield（25820 kg/hm²）and water use efficiency（3.94 kg/m³）were achieved under treatment W₂F₂．Based on principal component analysis of drip irrigation grape physiological growth, water and fertiliser use efficiency, yield and quality indicators for a comprehensive evaluation, with higher water use efficiency and yield and quality considerations, the optimal water and fertiliser treatment was W₂F₂, which was 6000 m³/hm² irrigation volume, fertiliser application of N, P₂O₅, K₂O were 240, 120 and 240 kg/hm², respectively．