|Samac, Deborah - Debby|
Submitted to: American Phytopathological Society Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 7/28/2007
Publication Date: 7/28/2007
Citation: Atkinson, L.M., Hollingsworth, C.R., Larsen, J.E., Samac, D.A., Motteberg, C.D. 2007. Aster yellows incidence and distribution within commercial small grains fields in Minnesota [abstract]. Phytopathology. 97:S5.
Technical Abstract: Aster yellows phytoplasma (AYp), vectored by the aster leafhopper (Macrosteles quadrillineatus), has a wide host range including wild and cultivated plants. Substantial yield losses in spring wheat (Triticum aestivum) have been observed in northwestern Minnesota which could be attributed to infestation by AYp. A 2-year survey of commercial small grain fields was conducted in northwest and west-central Minnesota to determine the incidence and distribution of AYp. Twenty-five plants were collected from each field along a 'W' transect line whereby five plants were arbitrarily selected at each of five points starting from the edge of the field working toward the center. Samples were evaluated for the presence of AYp by polymerase chain reaction (PCR) endpoint assay. In 2004, 44 of 156 fields (28.2%) tested positive for AYp by PCR assay, including 2 barley and 42 wheat fields. In 2005, 20 wheat fields out of 281 total fields (7.1%) tested positive for AYp. To further assess AYp distribution, a more sensitive, quantitative real time PCR assay was developed. Results show AYp infection occurs in a pattern from the edge of the field toward the center, indicating increased infection by leafhoppers residing in field edges and ditches. Understanding AYp spread and identifying infection patterns and cultivar response are critical components in managing yield loss due to aster yellow phytoplasma.