INCREASING RESISTANCE IN CELERY TO FUSARIUM-OXYSPORUM F SP APII RACE 2 WITH SOMACLONAL VARIATION

Somaclones were regenerated from cell suspension cultures derived from callus of celery cultivar Tall Utah 52-70 HK (moderately resistant to Fusarium oxysporum f. sp. apii race 2). Eighty-one of 350 somaclones screened for resistance to F. o. apii race 2 in either the greenhouse or the field had increased resistance over parental plants grown from seed. Thirty-five highly resistant somaclones (R0 generation) were self-pollinated, and 10 of the resulting R1 progeny lines were rated as highly resistant when screened in the field. Most of the R1 lines resembled parental Tall Utah 52-70 HK plants in appearance, growth rate, and habit. Twenty-six highly resistant plants from 11 R1 lines were self-pollinated, and nine of the resulting R2 lines were rated as highly resistant to F. o. apii race 2 in field trials. These lines were very similar horticulturally to the parent cultivar. The lines developed from this work could provide a source of increased resistance to F. o. apii race 2 for celery producers.