Somaclonal variation in celery: screening for resistance to Fusarium oxysporum f. sp. apii

Summary Two methods were used to screen putative Fusarium-resistant celery (Apium graveolens L.) plantlets from cell culture: placing plantlets on a mycelial mat for one month or planting them directly in Fusarium-infested soil. Resistant phenotypes were identified with both methods, but the plants grown on the mycelial mat died before they reached reproductive maturity. Four plants, K, T-2, T-3, and R-R₁ from the soil screen, survived and produced viable seed. Tests of self-pollinated progeny, in field and greenhouse conditions, showed that T-2, T-3, and R-R₁ were superior to the original cultivar, 5270R, with respect to disease resistance, as measured by vascular discoloration and plant height. Chi-square analysis of progeny scores for root and crown decay showed that the new variation was heritable and appeared to be conditioned by more than one locus.