Development of Efficient Screening Method for Resistance of Cabbage to Fusarium oxysporum f. sp. conglutinans

Abstract

This study was conducted to establish the efficient screening method for resistant cabbage to Fusarium wilt caused by Fusarium oxysporum f. sp. conglutinans. The resistance degrees of nine commercial cabbage cultivars to the disease were evaluated. Among them, five cultivars (YR-honam, Ogane, Greenhot, Redmat, and Ccoccoma) showing different resistance to the fungus were selected. Then development of Fusarium wilt of the cultivars according to several conditions including root wounding, dipping period of roots in spore suspension, inoculum concentration, and incubation temperature to develop the disease was investigated. Highly resistant cultivars such as ``YR-honam`` and ``Ogane`` hardly showed change of resistance to the disease by root wounding, dipping period, and inoculum concentration, while disease severity of Fusarium wilt on the cultivars was changed with incubation temperatures (20℃, 25℃ and 30℃). When the cabbage cultivars were incubated at 25℃, they represented the most difference of resistance and susceptibility to Fusarium wilt. From above results, we suggest that an efficient screening method for resistant cabbage to F. oxysporum f. sp. conglutinans is to dip the non-cut roots of 14-day-old seedlings in spore suspension of 1×107 conidia/ml for 0.5 hr and to transplant the seedlings to plastic pots with a fertilized soil, and then to cultivate the plants in a growth chamber at 25℃ for 3 weeks to develop Fusarium wilt.

Keywords

• Brassica oleracea
• Breeding
• Fusarium wilt
• Resistant screening