Research

Integrated management of Phytophthora root and stem rot of soybeans

Phytophthora root rot (PRR), caused by Phytophthora sojae, is a considerable threat to soybean production in Iowa, particularly in wet summers. Currently, PRR is primarily managed by planting soybean varieties with genes that confer resistance (Rps genes) to P. sojae. The effectiveness of a resistance gene relies on its ability to recognize the pathogen’s corresponding avirulence gene (Avr).

Optimizing yields of corn planted after a cereal rye cover crop

Profitable and sustainable use of foliar fungicides in corn production

Foliar fungicides have traditionally not been used in commercial corn because they have seldom been profitable. However, the use of foliar fungicides in hybrid corn production has increased dramatically in the past four years, primarily because of higher grain prices and physiological, yield-enhancing effects that are claimed by the agrochemical industry but are not related to reduced disease.

Pythium seed rot and damping off of corn and soybean

To optimize yield potential, soybean farmers in Iowa are planting earlier in the growing season. Together with reduced tillage practices, this often means that seed germinate in cold, wet soils and are at risk for seed rot and damping off due to soil borne pathogens such as Pythium spp., Phytophthora sojae, Fusarium spp.