Abstract:
Strawberry root rot is one of the main diseases of strawberry in Guanzhong, Shaanxi Province. In this report, the pathogen strains of strawberry root rot were isolated through tissue isolation method. And they were identified as
Fusarium solani and
Fusarium oxysporum through morphological and molecular biological methods. The inhibitory activity of four plant derived fungicides against two
Fusarium species was determined by mycelial growth rate test. Matrine + osthol 1.5% AS had the strongest inhibitory activity to
F. oxysporum with EC
50 value of 2.7 µg/mL, while matrine 0.3% EC had the strongest inhibitory activity to
F. solani with EC
50 value of 4.5 µg/mL. Three plant derived fungicides and three microbial fungicides (
Bacillus subtilis,
Bacillus polymyxa and
Trichoderma harzianum) were selected for field test against strawberry root rot. The 600 times dilution of
B. subtilis 100 billion spores/g WP had the best control efficacy against strawberry root rot, up to 69.25%. The control efficacy of 800 times dilution of
B. polymyxa 1 billion spores/g WP, 700 times dilution of matrine + osthol 1.5% AS and 200 times dilution of
T. harzianum 200 million spores/g WP were 63.14%, 62.84% and 59.74%, respectively. Therefore,
B. subtilis WP
,
B. polymyxa WP, matrine + osthol AS and
T. harzianum WP are recommended as field control agents for strawberry root rot.