Abstract
The greenbug [Schizaphis graminum (Rondani)] is an extremely damaging pest of barley (Hordeum vulgare L), particularly in the southern Great Plains of the USA. Two greenbug resistance genes, Rsg1a (in ‘Post 90’) and Rsg2b (in PI 426756), available for developing resistant barley cultivars, have similar phenotypes when challenged by various greenbug biotypes. This study was conducted to separate these two resistance genes via differential plant reactions to a recently collected field isolate of greenbug. Four barley entries and one wheat germplasm were challenged with two greenbug isolates and damage ratings were recorded for each combination. One greenbug isolate used in this study (TX1) was able to differentiate Rsg1a from Rsg2b through dramatically different plant responses (Rsg2b conferred resistance, Rsg1a did not). The results indicate the potential vulnerability of greenbug resistance genes in barley. Based on these and other reported results, we propose that gene symbol designations for greenbug resistance in barley be changed from Rsg1a to Rsg1 and Rsg2b to Rsg2.
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References
Franckowiak JD, Lundqvist U (2004) Rules for nomenclature and gene symbolization in barley. Barley Genetics Newsletter 34:132 [Online]. Available at http://wheat.pw.usda.gov/ggpages/bgn/34/rules.htm (verified 28 Feb. 2006).
Gardenhire JH, Chada HL (1961) Inheritance of greenbug resistance in barley. Crop Sci 1:349–352
Gardenhire JH, Tuleen NA, Stewart KW (1973) Trisomic analysis of greenbug resistance in barley, Hordeum vulgare L. Crop Sci 13:684–685
Merkle OG, Webster JA, Morgan GH (1987) Inheritance of a second source of greenbug resistance in barley. Crop Sci 27:241–243
Mornhinweg DW, Edwards LH, Smith EL, Morgan GH, Webster JA, Porter DR, Carver BF (2004) Registration of ‘Post 90’ barley. Crop Sci 44:2263
Porter DR, Burd JD, Shufran KA, Webster JA, Teetes GL (1997) Greenbug (Homoptera: Aphididae) biotypes: Selected by resistant cultivars or preadapted opportunists? J Econ Entomol 90:1055–1065
Porter DR, Mornhinweg DW (2004a) Characterization of greenbug resistance in barley. Plant Breeding 123:493–494
Porter DR, Mornhinweg DW (2004b) New sources of resistance to greenbug in barley. Crop Sci 44:1245–1247
Starks KJ, Burton RL (1977) Greenbugs: Determining biotypes, culturing, and screening for plant resistance with notes on rearing parasitoids. USDA Tech Bull 1556
Starks KJ, Webster JA (1985) Insects and related pests. In: Rasmusson DC (ed) Barley, ASA Mongr. 26, pp. 335–365. ASA, CSSA, and SSSA, Madison, WI
Tyler JM, Webster JA, Merkle OG (1987) Designations for genes in wheat germplasm conferring greenbug resistance. Crop Sci 27:526–527
Webster JA, Starks KJ (1984) Sources of resistance in barley to two biotypes of greenbug Schizaphis graminum (Rondani), Homoptera: Aphididae. Protect Ecol 6:51–55
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Porter, D.R., Burd, J.D. & Mornhinweg, D.W. Differentiating greenbug resistance genes in barley. Euphytica 153, 11–14 (2007). https://doi.org/10.1007/s10681-006-9193-5
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DOI: https://doi.org/10.1007/s10681-006-9193-5