Abstract: Use strawberry cultivar‘Benihoppe’as test material. The purpose of this study was to
investigate the relations of K-deficiency stress with continuous cropping obstacles of strawberry. The
results showed that the growth of shoot and root was inhibited，when strawberry plants were replanted in
first-crop substrates with K-deficiency（K+ 48.75 mg · L^-1），1/2K（K+ 415.58 mg · L^-1）and normal K（K+
782.41 mg · L^-1）treatments compared with control group. The plants with K-deficiency treatment had the
worst growth，while the growth of plants with 1/2K treatment was better than that with 1K treatment. Root
exudates of second-crop plants with K-deficiency treatment had a significant influence on growth of the
tissue cultural plantlets. The low concentration（1%，2%）promoted laterals growth and shoot growth and
high concentration（4%）inhibited root growth. When second-crop substrates were used to replant
strawberry plants and inoculated by Fusarium oxysporum and Verticillium dahliae，the diseases of
third-crop strawberry plants were worse at different periods than that of control group. The disease of
plants with K-deficiency treatment was the most serious，resulting in a 75 disease index after 10 days. 1/2K
treatment had lower disease index than normal K treatment. In conclusion，continuous cropping obstacles
of strawberry can be worse under the K-deficiency stress and appropriate K concentration had an important
role in preventing continuous cropping obstacles.

Key words: strawberry, K-deficiency stress, continuous cropping obstacle, root exudate, tissue cultural plantlet