## 1 Introduction
Living microorganisms (e.g., nematodes, bacteria, and fungi) can be applied to the seed, surface of the plant, or soil to colonize the rhizosphere and the interior of the plant to stimulate its growth and production of PSM by increasing the supply and availability of nutrients [10]. Specifically, some studies show that mycorrhizal inoculation can increase PSM content, such as polyphenols, and increase the antioxidant activity in plants [11], but effective formulations require a carrier material that must retain mycorrhizal functional properties after the administration. One way to protect and achieve targeted delivery of microorganisms to a plant is via the encapsulation method. Microorganisms, such as the fungus of the genus _Trichoderma_, participate in the degradation of plant residues in the soil and act as biocontrol agents against plant pathogens. _Trichoderma_ species synthesize specific compounds and metabolites, such as hydrolytic enzymes, plant growth promoters, antibiotics, siderophores, carbon, and nitrogen permeases. _Trichoderma_ spp., among other things, stimulates plant growth by dissolving otherwise insoluble mineral nutrients, such as calcium, iron, or aluminum phosphates [12]. Strong aggressiveness against plant pathogens and high efficacy in promoting plant growth and defense mechanism have made _Trichoderma_ species an important biocontrol agent [13]. However, biological agents are significantly influenced by detrimental external factors, such as pH, humidity, and ultraviolet radiation, which all impair their action. With encapsulation, a protective barrier around the biological control organism is provided, preserving its activity [14,15]. Compatibility of _Trichoderma viride_ spores with divalent ions, like Cu\({}^{2+}\), Ca\({}^{2+}\), Mg\({}^{2+}\) makes it pragmatic for simultaneous encapsulation into microparticles, that is, simultaneous delivery of chemical and biological agents to a plant. Calcium ions are essential macronutrients, and they have an important function in cell membrane structure and permeability, plant cell division and elongation, carbohydrate translocation, and nitrogen metabolism [16,17]. Ca\({}^{2+}\) plays a regulatory role in signal transduction and absorption of nutrients through the cell membrane [17,18,19]. Ca\({}^{2+}\) also signals the regulation of genesresponsible for polyphenol biosynthesis [20], and binds to the phospholipid membrane, stabilizing the lipid bilayer and maintaining the structure [21]. Furthermore, it was found that in Ca\({}^{2+}\)-treated plants, malondialdehydedehyde content decreases [18; 22; 23]. Although the soil is known to be rich in calcium, plants often lack calcium, due to their form and relative insolubility (e.g., CaCO\({}_{3}\)). In addition to Ca\({}^{2+}\), copper ions (Cu\({}^{2+}\)), as well as magnesium ions (Mg\({}^{2+}\)), also show a stimulating effect on PSM synthesis. They can stimulate PSM synthesis with a positive effect on alkaloid production, shikonin synthesis [24], digitalin production [25], and betaine [26]. Magnesium ion's primary role in plants relates to photosynthesis. Mg\({}^{2+}\) is an integral part of chlorophyll; it activates some enzymatic processes required for plant growth [27], participates in synthesizing DNA and RNA molecules [28], and is utilized in the plant's cellular energy source--ATP [27]. Cu\({}^{2+}\) plays key roles in photosynthetic and respiratory electron transport chains, on ethylene sensing, cell wall metabolism, oxidative stress protection, and biogenesis of the molybdenum cofactor [29]. Although Cu\({}^{2+}\) is an integral part of growth media and is known to be essential for several biochemical and physiological pathways [30], it becomes relatively toxic at high concentrations [31]. Therefore, it is important to control the dose through plant growth and development to minimize excess release into the environment.