John Spafford

My master’s research focused on increasing the productivity of asparagus through sustainable disease management tactics. The asparagus industry in Michigan is worth $23 million. The nutrient-rich, perennial vegetables are grown and sold for processing and fresh market sale. The production of asparagus is complicated, seeds are planted in crown nurseries and grown for a year. Crowns, the root system of the seedlings, are harvested and then replanted in production fields. Asparagus production is expensive and it takes several years before the spears can be harvested at a profit. When asparagus is healthy it can produce spears for 13 years. During this time it is exposed to a variety of diseases. In the soil Fusarium oxysporum f.sp. asparagi and Phytophthora asparagi can cause crown and root rot. Damage to the spears and fern are caused by the diseases Purple Spot (Stemphylium vesicarium) and Rust (Puccinia asparagi). Management practices for these diseases are typically costly, limited, and low impact. Asparagus production is declining nationwide, and growers are reporting high yield loss and shorter asparagus lifespans.