1. Spark is a synthetic variety with 98 parent plants. Parent plants

trace to 25 populations selected for resistance to the following

pests: bacterial wilt, Fusarium wilt, Verticillium wilt, Phytophthora

root rot and anthracnose. Phenotypic recurrent selection was used.

Final selections were made from 2- and 3-year-old space-plant

selection nurseries in Iowa, based on vigor, winter survival, color

and resistance to potato leafhopper yellowing. Parentage traces

predominantly to the varieties Apollo, Marvinskaja 425, Krasnodarskaja

Ranniaja, Armor, Thunder, Saranac AR, DK 120, Anchor, Arc, G-7730,

Titan