SYNERGETIC INFLUENCE OF EFFECTIVE MICROORGANISMS AND BEAUFORT ROOTS ON THE REGENERATION AND PHYSIOLOGICAL STATE OF GRAFTED TOMATO PLANTS

Abstract

The article examines the potential of EM technology integration into commercial vegetable growing of hybrid tomatoes. The aim of the research was to evaluate the effectiveness of the use of EM preparations (effective microorganisms) in the technology of growing grafted tomato plants and to determine their effect on graft survival on Beaufort Tm Cn VF¹Fr rootstock. Additional tasks of the research are to establish the optimal parameters for the preparation of grafting components, to clarify the relationship between the concentration and method of introduction of EM drugs and indicators of the physiological state of plants after vaccination, as well as to determine the potential of integrating EM technologies into the industrial nursery of hybrid tomatoes. Field experiments were conducted during 2019–2021 on the basis of the Central Ukrainian National Technical University in accordance with the «Methodology of field experiments in vegetable growing and melon growing». The work used grafted tomato plants of the Pink Delight F₁ hybrid on the Beaufort Tm Cn VF¹Fr rootstock. The study included three treatment options: control without EM technology, EM5 + EM Agro in standard concentration (1:100) and increased concentration (1:50). EM drugs were applied by soaking the rootstock and scion before grafting (10–15 min), followed by spraying the plants in the rooting chamber and applying it to the substrate. Vaccination was performed by the method of apical convergence using silicone clips with a diameter of 1.5–2.0 mm. The plants were placed in a chamber with a controlled microclimate (temperature 24–26 °C, relative humidity 85–95%, darkness 60–70% during the first three days). For 14 days, the percentage of survival, callus formation rate, morphometric parameters, SPAD index and the frequency of physiological abnormalities were determined. The use of EM preparations significantly increased the survival of grafted tomato plants: the use of EM5 + EM Agro at a concentration of 1:100 ensured survival of 94.8% on the 14th day after vaccination against 82.5% in the control, and the increased concentration (1:50) made it possible to reach 96.4%. The process of callus formation accelerated by 2.4–3.1 days, decreasing from 9.2 days in the control to 6.1–6.8 days in the variants with EM treatment. The morphometric indicators of plants on the 21st day after inoculation improved significantly: height increased by 17.9–25.5%, stem diameter by 16.7–22.9%, leaf surface area by 25.0–35.2% compared to the control. The SPAD index in EM-treated variants was higher by 15.9–20.4%, which indicates better preservation of the photosynthetic apparatus. The incidence of wilting decreased from 24.6% to 5.2–8.4%, tissue necrosis from 12.3% to 1.5–3.1%, rupture at the graft site from 5.2% to 1.5–2.1%. The economic analysis showed the high efficiency of the technology: the yield of standard seedlings increased by 14.9–16.8%, providing an additional profit of UAH 1,845–2,085 per 1,000 grafted plants with a profitability of additional costs of 613–1,025%. EM preparations are an effective tool for increasing the survival of grafted tomato plants on Beaufort Tm Cn VF¹Fr rootstock. The optimal concentration for production conditions is EM5 + EM Agro 1:100, which ensures survival over 94%, accelerates healing by 2–3 days and is characterized by the highest profitability (1,025%). The combination of the genetic advantages of the Beaufort rootstock with the stimulating effect of EM drugs on the microbiome provides a synergistic effect, manifested in high survival, improved morphometric and physiological indicators of plants. The technology has a significant potential for introduction into the industrial nursery of tomatoes under conditions of protected soil.