Diagnosis and Detection of Seed-Borne Pathogens in Field Crops

The befitting detection and identification of casual agents responsible for the seed-borne diseases of crop plants are considered to be the most important issue in formulating management strategies. Since diseased seeds frequently show no symptoms, it is critical to diagnose them early in order to prevent pathogen spread through long-distance germplasm exchange. In order to manage diseases of crops, it is crucial to conduct seed health testing in order to identify seed-borne pathogens. By doing so, financial losses and unnecessary fungicide use can be avoided, which lowers costs and reduces the environmental impact of such hazardous chemicals. The primary criteria for choosing seed health test procedures are specificity, sensitivity, speed, ease of use, affordability, and dependability. Conventional methods for identifying fungus transmitted by seeds rely on the processes of incubation and grow-out. These are lengthy, entail microbiological abilities, and are occasionally not sensitive enough to low levels of seed infection while being widely utilized due to their ease of application. Because of their high levels of specificity and sensitivity, novel identification approaches based on DNA analysis have been used frequently and have proven to be quite efficient. During the identification of fungi, bacteria, viruses, and other seed-borne diseases, a variety of diagnostic techniques—from eye inspection to PCR-based molecular methods—are employed in accordance with ISTA criteria. Conventional PCR is the simplest and most widely used method; more modern approaches include nested PCR, which eliminates low concentrations of specific pathogens; multiplex PCR, which detects many pathogens at once; real-time PCR, which measures fungus on seeds; and magnetic capture hybridization-PCR. The incapacity to differentiate between essential and non-essential inocula and the challenge of getting high-quality DNA templates because of PCR inhibitors in seeds are the primary limitations of molecular techniques. Numerous modified PCR processes, including loop-mediated isothermal amplification, and non-destructive testing techniques have been designed to lessen the inhibitory effect. Considering the many benefits they offer, loop-mediated isothermal amplification and next-generation sequencing have found extensive use in nucleic acid analysis. In the future, their use for the identification of fungal infections in seeds may be greatly expanded.