Categories of Resistance at Different Growth Stages in Halt, a Winter Wheat Resistant to the Russian Wheat Aphid (Homoptera: Aphididae)

Abstract

This study was designed to categorize the resistance to the Russian wheat aphid, Diuraphis noxia (Mordvilko), resistant hard red winter wheat, Halt, as compared with susceptible wheat, TAM 107, at four different growth stages. Antixenosis was expressed in Halt at growth stage Zadoks 30. Antibiosis in Halt affected fecundity, number of aphids produced per reproductive day, maximum number of nymphs produced in one day, and intrinsic rate of increase. Fecundity was lower on Halt than TAM 107, and more nymphs were produced on both varieties at growth stage 20 than 10 and 40. Fewer nymphs were produced per reproductive day and on maximum production days by aphids reared on Halt than by those reared on TAM 107. The intrinsic rate of increase of Russian wheat aphids reared on Halt was lower than aphids reared on TAM 107. Differences in plant height and plant dry weight did not occur. Chlorosis ratings showed greater damage at the earlier stages in Halt and TAM 107 and significantly more damage in TAM 107 than Halt at growth stages 10, 20, and 30. Leaf rolling occurred on infested plants of TAM 107 at growth stages 10, 20, and 30, but not growth stage 40. Halt plants did not exhibit leaf rolling. The presence of a significant level of tolerance could make Halt compatible with other integrated pest management programs. However, care should be taken with cultivars containing evidence of antixenosis or antibiosis that could cause selective pressure on the Russian wheat aphid, potentially causing biotypes to be produced.

Physiological and Biochemical Responses of Resistant and Susceptible Wheat to Injury by Russian Wheat Aphid

“…Seeds of susceptible wheat ÔTAM 107Ј and the resistant wheat ÔHaltÕ and ÔPrairie RedÕ were planted in SC-10 Super Cell Cone-tainers (3.8 by 21 cm) (Stuewe & Sons, Inc., Corvallis, OR). The resistant Halt and Prairie Red both carry the Dn4 gene (Quick et al 1996, Hawley et al 2003. Three seeds of each cultivar were planted in a Cone-tainer to a depth of Ϸ2 cm in a mixture of sandÐsoilÐpeatÐperlite (0.66:0.33:1:1) and placed in Cone-tainer racks.…”

“…The resistant Prairie Red and Halt supported similar numbers of aphids throughout the experiment, demonstrating that the two resistant cultivars display tolerance to D. noxia. Studies by Randolph et al (2005a) and Hawley et al (2003) have previously characterized Prairie Red and Halt as conveying tolerance in the seedling stage and antibiotic properties at later stages of development.…”

“…Wheat cultivars containing D. noxia-resistant genes, which have different levels of antibiosis, tolerance, or both (Randolph et al 2005a), have been shown to harbor fewer D. noxia populations and have higher yields compared with their susceptible wheat counterparts (Randolph et al 2003(Randolph et al , 2005b. Resistant plants also have demonstrated compatibility with other management tactics by exhibiting an absence of leaf rolling when infested with D. noxia, which would expose the aphids to chemical and biological management (Hawley et al 2003).…”

Differential colonization of wheat cultivars by two biotypes of Russian wheat aphid (Homoptera: Aphididae)

“…Migui and Lamb (2004) found disparity between seedlings and adult plants in terms of the resistance of Triticum monococcum to Sitobion avenae (F.), the former exhibiting primarily antibiosis and the latter, primarily tolerance. Hawley et al (2003) detected D. noxia antixenosis in wheat cv. Halt specifically at the jointing stage, Zadoks 30, but not in TAM107 at the same growth stage.…”

Integration of Plant Defense Traits with Biological Control of Arthropod Pests: Challenges and Opportunities

“…For example, the leaves of winter wheat varieties developed for resistance to Russian wheat aphid Diuraphis noxia (Kurdjumov) (Hemiptera: Aphididae) remain flat, compared to susceptible varieties whose leaves furl in response to aphid feeding (Hawley et al, 2003), exposing aphids to disturbances such as wind, rain, and predators inducing them to fall from the plant (von Berg et al, 2008). Characteristics that affect falling behavior of herbivores can affect predation rates as they experience vulnerability to ground-dwelling predators and may also face additional challenges from natural enemies as they attempt to recolonize the plant (Sunderland et al, 1986; Winder, 1990; Winder et al, 1994).…”