From Select Agent to an Established Pathogen: The Response to Phakopsora pachyrhizi (Soybean Rust) in North America

Abstract

The pathogen causing soybean rust, Phakopsora pachyrhizi, was first described in Japan in 1902. The disease was important in the Eastern Hemisphere for many decades before the fungus was reported in Hawaii in 1994, which was followed by reports from countries in Africa and South America. In 2004, P. pachyrhizi was confirmed in Louisiana, making it the first report in the continental United States. Based on yield losses from countries in Asia, Africa, and South America, it was clear that this pathogen could have a major economic impact on the yield of 30 million ha of soybean in the United States. The response by agencies within the United States Department of Agriculture, industry, soybean check-off boards, and universities was immediate and complex. The impacts of some of these activities are detailed in this review. The net result has been that the once dreaded disease, which caused substantial losses in other parts of the world, is now better understood and effectively managed in the United States. The disease continues to be monitored yearly for changes in spatial and temporal distribution so that soybean growers can continue to benefit by knowing where soybean rust is occurring during the growing season.

Organically Grown Soybean Production in the USA: Constraints and Management of Pathogens and Insect Pests

“…The disease is more prevalent in subtropical and tropical regions, but has become a regular concern in the southern USA [68]. The fungus is an obligate biotroph and will form haustoria in plant tissues to remove photosynthates from leaves.…”

“…The disease is commonly managed with the application of fungicides. Although sources of resistance are known, resistant cultivars are not yet commercially available in the USA [68]. For management in an organic system, there are a number of studies that have shown that fungicides, including copper-based fungicides, can effectively reduce the severity of this disease [69].…”

Integrating Phenological, Aerobiological and Weather Data to Study the Local and Regional Flowering Dynamics of Four Grapevine Cultivars

“…Likewise, the significant correlation coefficient increases to 0.995 (p = 0.005) when the 'Treixadura' cultivar plot harvest is compared with the pollen registered by the Hirst method. Therefore, the comparison of data from the Hirst and Cour traps is valuable for determining whether local data are representative of the region as a whole [19]. Further investigations with a greater number of study years may corroborate this behavior.…”

“…For this purpose, different pollen trapping methodologies have been considered. Passive traps were the former used for the determination of the total pollen concentration [15,18] or for spore sampling in the atmosphere of vineyards [19]. During recent years, works using volumetric traps have frequently been conducted [20][21][22][23][24].…”

Hourly and daily changes on airborne urediniospores of Phakopsora pachyrhizi

“…Syd.) of soybean (Glycine max L.) is a destructive foliar disease found in many soybeanproducing regions (YORINORI et al, 2005;ISARD et al, 2006;JARVIE 2009;ROSA et al, 2015;KELLY et al, 2015;MAUMARY et al, 2016;GODOY et al, 2016). Weather conditions influence directly in the cycle of the pathogen, which favors the development of rust epidemics on soybean (ISARD et al 2005).…”