Breeding for Resistance in California Strawberry to Verticillium dahliae

Since 1930 the University of California, Davis, has been developing strawberry cultivars that are adapted to the agricultural industry and regional farms. Developing cultivars that require fewer inputs are of significant economic importance in agronomy. Developing a crop resistant to a disease is beneficial for horticulturists since less labor and chemicals are needed for a high yield.6 In commercial strawberry cultivars, complete resistance to V. dahlia is extremely rare. The majority of Californian strawberry cultivars are highly susceptible to it.2 Over the last 18 years of plant breeding for strawberry cultivars with a high degree of resistance and horticultural traits, strawberry cultivars with at least moderate resistance grew to 53.8% of the strawberry germplasm being measured in the study. Each plant was rated from 1 to 5 based on symptoms of V. dahliae in comparison to control plants over the length of the study. The lowest ranking was 1 meaning severe stunting or death A ranking of 3 indicated moderate damage and signs of tolerance The highest ranking was 5 indicating no disease symptom