Encapsulation of Plant Biocontrol Bacteria with Alginate as a Main Polymer Material.

Roohallah Saberi Riseh,Vijay Kumar Thakur,Shahnaz Shahidi Noghabi,Yury A Skorik,Elahe Tamanadar,Mojde Moradi Pour

doi:10.3390/ijms222011165

Abstract

One of the most favored trends in modern agriculture is biological control. However, many reports show that survival of biocontrol bacteria is poor in host plants. Providing biocontrol agents with protection by encapsulation within external coatings has therefore become a popular idea. Various techniques, including extrusion, spray drying, and emulsion, have been introduced for encapsulation of biocontrol bacteria. One commonly used biopolymer for this type of microencapsulation is alginate, a biopolymer extracted from seaweed. Recent progress has resulted in the production of alginate-based microcapsules that meet key bacterial encapsulation requirements, including biocompatibility, biodegradability, and support of long-term survival and function. However, more studies are needed regarding the effect of encapsulation on protective bacteria and their targeted release in organic crop production systems. Most importantly, the efficacy of alginate use for the encapsulation of biocontrol bacteria in pest and disease management requires further verification. Achieving a new formulation based on biodegradable polymers can have significant effects on increasing the quantity and quality of agricultural products.

Highlights

Sodium alginate (ALG) is a polysaccharide found abundantly in the cell walls of brown algae (e.g., Macrocystis pyrifera, Ascophyllum nodosum, and Sargassum sinicola) and some bacterial species (e.g., Pseudomonas and Azotobacter) [1]
The properties of ALG vary depending on its origin, and they change with the M/G ratio and the molecular weight (MW) [5]
The main purpose of this review is to introduce an effective technology for the encapsulation of bacteria known to be effective in the management of pests and plant diseases

Summary

Introduction

Sodium alginate (ALG) is a polysaccharide found abundantly in the cell walls of brown algae (e.g., Macrocystis pyrifera, Ascophyllum nodosum, and Sargassum sinicola) and some bacterial species (e.g., Pseudomonas and Azotobacter) [1]. ALG has a similar role in seaweed to that of cellulose in plants and occurs as a mixture of insoluble calcium, magnesium, potassium, and sodium salts in the cell walls of seaweeds. ALG is a linear copoly–mer with homopolymeric blocks of (1→4)-linked β-D-mannuronate (M) and α-Lguluronate (G) residues linked together in different sequences (Figure 1a). ALG is soluble in water and is formed by the dissolution of a liquid with a high viscosity [3]. This substance is a type of gum that can be dissolved in both cold and hot water and that forms irreversible gels when it reacts with calcium salts or acids [4]. The properties of ALG vary depending on its origin, and they change with the M/G ratio and the molecular weight (MW) [5]

Objectives

Methods

Findings

Conclusion