ABSTRACT

This chapter discusses the important methods of seed health testing. Seed health testing determines whether or not a seed lot should be treated with a fungicide or other treatment based on the nature and degree of infection associated with the seeds. It helps to develop more precise seed treatment and to avoid unnecessary seed treatment of healthy seeds. Certain fungi can be detected by direct observation of dry seeds or by using a stereobinocular bright-field microscope or hand lens to detect. The two methods used for examination of crop seeds for fungal infections viz., blotter method and agar plate method. These methods are suitable for infections accompanied by hyphae, fruiting structures or spores. Viruses are obligate parasites and they differ in their genetic make up and require special techniques for detection. Seed borne nature of the virus is found by either raising seedlings from infected seeds or observing symptoms or by using assays of seed extract.