Microbial biostimulants enhance soybean yield and seed quality under hydrothermal stress in organic farming

Chaika, T.; Короткова, Ірина Валентинівна; Korotkova, I. V.; Ляшенко, Віктор Васильович; Liashenko, V. V.; Рибальченко, Анна Михайлівна; Rybalchenko, A. M.; Міленко, Ольга Григорівна; Milenko, O. H.

Публікація:
Microbial biostimulants enhance soybean yield and seed quality under hydrothermal stress in organic farming

dc.contributor.author	Chaika, T.
dc.contributor.author	Короткова, Ірина Валентинівна
dc.contributor.author	Korotkova, I. V.
dc.contributor.author	Ляшенко, Віктор Васильович
dc.contributor.author	Liashenko, V. V.
dc.contributor.author	Рибальченко, Анна Михайлівна
dc.contributor.author	Rybalchenko, A. M.
dc.contributor.author	Міленко, Ольга Григорівна
dc.contributor.author	Milenko, O. H.
dc.date.issued	2026-09-09
dc.description	Chaika T., Korotkova I., Liashenko V., Rybalchenko A., Milenko O. Microbial biostimulants enhance soybean yield and seed quality under hydrothermal stress in organic farming. Studia Biologica. 2026. Vol. 20 (2). P. 151–166. DOI: 10.30970/sbi.2002.889
dc.description.abstract	Background. In organic farming conditions under increasing frequency of hydro thermal stress, ensuring stable soybean yield and seed quality requires the use of bio logical preparations capable of activating plant adaptive mechanisms. The integrated application of arbuscular mycorrhizal fungi, nitrogen-fixing bacteria, and microbial biostimulants with phytohormonal activity may improve plant water status, reduce oxi dative damage, and enhance seed biochemical composition. However, the effects of such multicomponent systems on yield structure components, seed protein, oil, and nitrogen content under variable hydrothermal conditions remain insufficiently studied. Materials and Methods. Field experiments were conducted in 2022–2024 under organic farming conditions in the Left-Bank Forest-Steppe of Ukraine using the early maturing soybean cv. Khorol. Eight treatment variants were evaluated: control, Profix, Violar, Mycofriend, Profix + Violar, Mycofriend + Profix, Mycofriend + Violar, and Mycofriend + Profix + Violar. Seed protein and oil content were determined by NIR spectroscopy; relative water content (RWC), stomatal conductance (gs), abscisic acid (ABA), and malondialdehyde (MDA) were assessed at the BBCH 61 stage. Statistical analysis included one-way ANOVA followed by Tukey’s HSD test, Pearson correlation, and principal component analysis (PCA). Results. The highest yield (2.96–3.57 t/ha) and seed quality were recorded under the Mycofriend + Profix + Violar treatment across all years, exceeding the control by 40.6–59.1%. Seed protein content increased by up to 5.7 percentage points, and oil content reached 19.3 %. Yield gains were primarily driven by an increased number of seeds per plant (up to 130), while thousand-seed weight remained relatively sta ble. Under hydrothermal deficit in 2024, combined treatments maintained higher RWC (up to 91.9 %), lower MDA (-47.7 % vs. control), and reduced ABA accumulation, with strong correlations confirmed between RWC and yield (r = 0.92; P < 0.001) and between ABA and gs (r = -0.98; P < 0.001). Conclusion. The complex application of Mycofriend, Profix, and Violar in organic soybean cultivation consistently improved yield, seed nutritional quality, and physiologi cal stress tolerance across years with contrasting hydrothermal conditions. Stabilization of plant water status and limitation of oxidative damage were identified as key mecha nisms underlying productivity maintenance under drought.
dc.identifier.uri	https://dspace.pdau.edu.ua/handle/123456789/22395
dc.language.iso	en
dc.subject	arbuscular mycorrhizal fungi
dc.subject	rhizobia
dc.subject	phytohormones
dc.subject	abscisic acid
dc.subject	malondialdehyde
dc.subject	relative water content
dc.title	Microbial biostimulants enhance soybean yield and seed quality under hydrothermal stress in organic farming
dc.type	Article
dspace.entity.type	Publication