Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 9/30/1997
Publication Date: N/A
Technical Abstract: Several biotypes of greenbug (Schizaphis graminum Rondani) attack winter wheat (Triticum aestivum L.) in the Southern Plains every year. We compared two wheat germplasm sources of resistance (Largo and GRS 1201) that provide protection against the three predominant greenbug biotypes (E, I, and K). Components of resistance (i.e., antixenosis, antibiosis, and tolerance) were measured on seedlings of GRS 1201, Largo, and TAM W-101 (a susceptibl control). Total number of aphids produced per plant, selection preferences, and plant damage ratings were recorded for each plant entry. Data recorded for each resistance component were normalized and combined to derive a Plant Resistance Index (PRI) for each wheat entry. Results of this analysis suggest that GRS 1201 had a much higher level of combined resistance components, with a PRI of 90, than did Largo, with a PRI of 25. The susceptible control TAM W-101 had a PRI of 1.