Bioencapsulation of Microbial Inoculants: Mechanisms, Formulation Types and Application Techniques

Abstract

The excessive use of agrochemicals in the field to increase production and counteract the negative effects caused by biotic and abiotic factors has led to a deterioration in soil fertility, plus an increment in negative impacts on the environment and human health. Therefore, the application of beneficial microorganisms as bioinoculants is an eco-friendly alternative to agrochemicals. Plant growth-promoting bacteria and fungi have been effective in promoting plant growth and production, as well as reducing the action of pathogens in multiple crops. However, successful application of such beneficial microorganisms in the agricultural field has faced several difficulties, such as survival, colonization efficiency and short periods of shelf storage. Therefore, it is essential to explore novel ways to encapsulate, formulate and apply bioinoculants. To obtain the expected quality in bioencapsulated products, it is essential to determine the type of polymer, capsule size, encapsulation technique and use the correct chemical and physical cofactors involved in the production process. Thus, this review highlights the various formulation types and application techniques, as well as discussing the multiple advantages of using microbial encapsulates to have better results in agricultural production.

Fungi That Promote Plant Growth in the Rhizosphere Boost Crop Growth

“…The symbiotic associations of AM or PGPF with crop plants improve the evolution of plants in heavy-metal-contaminated areas by the following processes: phytohormone production, pathogenic resistance, nutrient acquisition, water relations, amelioration of the soil structure, and contribution to soil aggregation and therefore promote bioremediation processes. For example, PGPF and AMF have been reported to reduce caesium assimilation by plants [ 124 ] and therefore could be employed in the production of plantations on soil contaminated with radionuclides and so possess the ability to decrease danger caused to the environment. PGPF and AMF also possess the ability to monitor the toxicity of the soil [ 16 ] and its effectiveness.…”

“…These organisms are primarily found in the rhizosphere region of healthy plants, where they control the invasion of disease-causing organisms ( Table 1 ). Rojas-Sánchez, et al [ 124 ] explained how PGPF dwells in root cells, root surfaces, and the outer layers of root cells. De Palma, et al [ 157 ] reported how Trichoderma spp.…”

Perspectives on the Use of Biopolymeric Matrices as Carriers for Plant-Growth Promoting Bacteria in Agricultural Systems

“…Gelatin exhibits amphoteric behavior due to the presence of both basic and acidic groups [ 125 ]. It is easily soluble in water at an average temperature of 40 °C, forming a viscous solution by chain association and three-dimensional network formation, resulting in gels on cooling below 35 °C; above this temperature, gelatin exists as a single molecule because it is unable to form interchain hydrogen bonds [ 126 , 127 , 128 , 129 ]. Gelatin films are clear, flexible, strong, and oxygen permeable [ 129 ].…”

Agroecological Management of the Grey Mould Fungus Botrytis cinerea by Plant Growth-Promoting Bacteria

“…It can be hypothesised that the bacteria that reside in the rhizosphere defend the plant more forcefully through the synthesis of antibiotics before the pathogen approaches and colonises the plant surface. PGPB are excellent microbial biocontrol agents that play an important role in the antagonism and control of fungal plant pathogens [ 30 , 49 , 50 ], such as B. cinerea [ 24 , 51 , 52 ].…”