Healthy seed
Healthy seed production is also referred to as certified seed production. It involves selection of true to type, healthy looking plants and collection of tubers from these plants individually as clones. The clones are then tested for freedom from various viruses and only the virus-free clones are then multiplied in the field under specified conditions and prescribed agronomic practices under the supervision of qualified persons who undertake the testing of the crop in the field and remove and destroy the plants found infected with viruse(s). Such a healthy produce is referred as breeder seed or basic seed. Basic seed is then further multiplied under prescribed conditions.