Evaluation of chemical composition modification of garden strawberry fruits when using microbial-auxin plant growth promoter

Abstract

The research findings on the effect of a microbial-auxin plant growth promoter by the example of garden strawberry (Fragaria × ananassa Duch.) of the mid-season variety “Elsanta” are discussed. The study was conducted in the territory of a private garden property in the Moscow Region; the plants were divided into four groups: 1st group - control (watering), 2nd group - treatment with auxin (indole-3-butyric acid) in mono-mode, 3rd group - treatment with a microbial consortium based on Pseudomonas aureofaciens and 4th group of plants treated with a complex microbial-auxin promoter. The methods of agro-technical analysis were used: phenological observation, yield accounting, morphometric indices of fruits; the methods of biochemical analysis of the chemical composition of fruits: titrimetry, high-performance liquid chromatography (HPLC), spectrophotometry, inductively coupled plasma mass spectrometry, quenching of the stable DPPH radical and in the FRAP test. The obtained data indicate a clear synergistic effect from the combined use of auxin and the microbial consortium which exceeds the individual effect of each component. The use of a microbial auxin promoter had a statistically significant complex effect on the productivity and biochemical composition of fruits of the garden strawberry variety “Elsanta”. Treatment with a complex preparation causes a targeted modification of the chemical composition of strawberry fruits towards optimizing the sugar-acid balance and significantly increasing their biochemical and functional value by activating the synthesis of vitamins, phenolic compounds and improving the mineral composition. The use of microbial auxin promoter proved to be an efficient agricultural technique for managing strawberry fruit quality allowing for simultaneous increases in yield, improved flavor, and increased content of bioactive compounds. The effect of the promoter is systemic affecting various aspects of plant metabolism confirmed by changes in a wide range of examined indices.