Multi-nutrient fertilization-based analysis of fruit quality and mineral elements composition during fruit development in Merlot

Abstract

Abstract [Purpose] Mineral elements are very important to plant growth and development, and the proper supply of mineral elements in soil and the optimum range of mineral elements in plant are necessary to guarantee the optimal yield and quality of fruit trees. The application of NPKCaMg fertilizers to fruit trees is frequently insufficient or excessive, which not only causes environmental degradation, but also reduces yield and quality of fruit. [Methods] In order to assess the effects of different fertilizers on biological-related traits of grape fruit and responses to nutritional elements, grapevine (Merlot) was treated with multi-nutrient fertilization for 4 consecutive growing seasons in 2018–2021 at Penglai, Yantai in China. [Results] The principal component analysis showed that the T11 treatment was the appropriate type and rate of fertilizer for this experiment. A 24.29%-35.20% reduction in fertilizer application with T11 treatment (N3P3K1Ca2Mg4) increased HGW, SN, TSS, SP, SFI, and ST, by 3.28%-12.84%, 3.76%-20.03%, 1.11%-14.95%, 2.16%-23.69%, 11.00%-32.78%, 1.07%-23.35%, respectively, compared to T14 (N4P2K3Ca1Mg4), T16 (N4P4K1Ca3Mg2), T13 (N4P1K4Ca2Mg3) and T15 (N4P3K2Ca4Mg1) treatment. The process of flower and fruiting behavior, the floral organs have a large demand for NPK. The requirement for K and B during the growth and development of the fruit was higher than that of other mineral elements. Excess K in soil enhanced the competitive inhibition of Ca uptake by Merlot. The optimum ranges of mineral element content for PP, PFI, PFD, SP and ST in Merlot were mainly related to the grape varieties and nutritional diagnosis methods. [Conclusions] In conclusion, careful selection of NPKCaMg fertilizer supply to soil and optimum range of mineral elements in plant are important basis for proper growth and development of vine.