title: A Relative Resistance Ratio for Evaluation of Mexican Rice Borer (Lepidoptera: Crambidae) Susceptibility Among Sugarcane Cultivars.
abstract: The Mexican rice borer, Eoreuma loftini (Dyar), is a major pest of sugarcane (hybrids of Saccharum spp.) in Louisiana and Texas. Resistance to E. loftini was evaluated in 51 commercial and experimental cultivars of sugarcane, energycane (hybrids of Saccharum spp.), and sorghum [Sorghum bicolor (L.) Moench and hybrids of Sorghum spp.] in four replicated small plot field experiments from 2009 to 2012. A relative resistance ratio was developed to compare levels of susceptibility among cultivars based on the percentage of bored internodes and survival to adulthood. This index was able to separate cultivars into five resistance categories and provides a new method for comparing levels of resistance among cultivars. E. loftini pest pressure in 2009 was among the highest recorded with injury ranging from 55 to 88% bored internodes. Commercial sugarcane cultivar HoCP 85-845 was identified as resistant in three of four experiments, whereas HoCP 04-838 was identified as susceptible in all experiments. Of the five sugarcane cultivars in commercial production in the Rio Grande Valley of Texas, only TCP 87-3388 was categorized as resistant. Of the cultivars with potential for bioenergy production, all of the energycane cultivars demonstrated higher levels of resistance than high-biomass and sweet sorghum cultivars. Continued evaluation of cultivar resistance to E. loftini is important to development of effective integrated pest management strategies for this pest.
authors.affiliation: Department of Entomology, Louisiana State University Agricultural Center, 404 Life Science Bldg., Baton Rouge, LA 70803, USA bwils26@lsu.edu.
authors.forename: Blake E
authors.initials: BE
authors.lastname: Wilson
authors.affiliation: Department of Entomology, Louisiana State University Agricultural Center, 404 Life Science Bldg., Baton Rouge, LA 70803, USA.
authors.forename: Matthew T
authors.initials: MT
authors.lastname: VanWeelden
authors.affiliation: Dean Lee Research Station, Louisiana State University Agricultural Center, 8105 Tom Bowman Dr., Alexandria, LA 71302, USA.
authors.forename: Julien M
authors.initials: JM
authors.lastname: Beuzelin
authors.affiliation: Department of Entomology, Louisiana State University Agricultural Center, 404 Life Science Bldg., Baton Rouge, LA 70803, USA.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Reagan
authors.affiliation: Texas A&M AgriLife Research and Extension Center, 1509 Aggie Dr., Beaumont, TX 77713, USA.
authors.forename: Michael O
authors.initials: MO
authors.lastname: Way
authors.affiliation: USDA-ARS Sugar Cane Research Unit, 5883 USDA Rd., Houma, LA 70360, USA.
authors.forename: William H
authors.initials: WH
authors.lastname: White
authors.affiliation: Texas A&M AgriLife Research and Extension Center, 1509 Aggie Dr., Beaumont, TX 77713, USA.
authors.forename: Lloyd T
authors.initials: LT
authors.lastname: Wilson
authors.affiliation: USDA-ARS Knipling-Bushland U.S. Livestock Insects Research Laboratory, 2700 Fredericksburg Rd., Kerrville, TX 78028, USA.
authors.forename: Allan T
authors.initials: AT
authors.lastname: Showler
mesh_terms: D000818:Animals; D020387:Food Chain; D060434:Herbivory; D007300:Insect Control / Q000379:methods*; D007814:Larva / Q000254:growth & development / Q000502:physiology; D009036:Moths / Q000254:growth & development / Q000502:physiology*; D031786:Saccharum / Q000235:genetics / Q000502:physiology*; D013781:Texas
keywords: Eoreuma loftini; Saccharum spp.; cultivar resistance