title: Resistance to Melanaphis sacchari (Hemiptera: Aphididae) in Forage and Grain Sorghums.
abstract: The sugarcane aphid, Melanaphis sacchari (Zehntner), has established itself as a perennial pest of grain and forage sorghums in the United States since the summer of 2013. We conducted traditional plant resistance studies that determine tolerance, antibiosis, and antixenosis in 32 sorghum genotypes when challenged with sugarcane aphids. The genotypes included one exotic plant introduction and 31 seed and pollinator parental lines that are used to produce grain, sudangrass, and forage sorghum hybrids. One seed parent (B11055) and one grain pollinator parent (R13219) expressed significant degrees of tolerance, antibiosis, and antixenosis and were top performers in all three resistance type experiments. An additional group of seed parents (B13045 and B1057) and grain pollinator parents (R11159, R13422, and RTx2908) and the plant introduction (PI 550610) resulted in an intermediate range of phenotypic resistance (i.e., 4.0 < 6.0) indicative of antibiosis from reduced fecundity, increased intrinsic rate of increase, and increased generation times. The forms of resistance expressed in these lines, especially B11055 and R13219, have great potential in breeding programs that can be integrated into useable forms of resistant sorghums.
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, Wheat, Peanut and Other Field Crops Research Unit, Stillwater, OK, USA.
authors.forename: J Scott
authors.initials: JS
authors.lastname: Armstrong
authors.affiliation: Department of Soil and Crop Sciences, Texas A&M University, College Station, TX, USA.
authors.forename: Lloyd
authors.initials: L
authors.lastname: Mbulwe
authors.affiliation: Texas A&M AgriLife Research and Extension Center, Weslaco, TX, USA.
authors.forename: Danielle
authors.initials: D
authors.lastname: Sekula-Ortiz
authors.affiliation: University of Kentucky Research and Education Center, Hopkinsville Street Princeton, KY, USA.
authors.forename: Raul T
authors.initials: RT
authors.lastname: Villanueva
authors.affiliation: Department of Soil and Crop Sciences, Texas A&M University, College Station, TX, USA.
authors.forename: William L
authors.initials: WL
authors.lastname: Rooney
mesh_terms: D000818:Animals; D000898:Antibiosis; D001042:Aphids / Q000502:physiology*; D060434:Herbivory; D045868:Sorghum / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D013781:Texas
keywords: Melanaphis sacchari; forage sorghum; grain sorghum; resistance