Narrative
Guymon most closely resembles the HW wheat cultivar, Intrada (PI 631402), one of its two parents, on the basis of kernel size (relatively small), juvenile plant growth habit (semi-erect) and winter dormancy release pattern (relatively early), test weight (high), and resistance to wheat soilborne mosaic virus and susceptibility to current races of stripe rust (caused by Puccinia striiformis Westend). Plant stature is moderately tall, averaging 80 cm in Oklahoma, or 2 cm taller than Intrada. Unlike Intrada, Guymon has good straw strength under conditions of significant or severe lodging. Guymon has higher (19%) grain yield capacity than Intrada when measured in high-yielding environments free of stripe rust. Based on field observations in Oklahoma, Guymon is resistant to Wheat soilborne mosaic and Wheat spindle streak mosaic virus. Based on field observations of adult plants across Oklahoma through 2006, it shows a resistant reaction to leaf rust, caused by Puccinia triticina Eriks. Based on greenhouse observations, Guymon is susceptible to tan spot (Pyrenophora tritici-repentis) and to powdery mildew (Blumeria graminis f. sp. tritici), and it shows an intermediate reaction to septoria leaf blotch (Septoria tritici). It is susceptible to biotypes C and E of the greenbug (Schizaphis graminum Rondani) and to the Great Plains biotype of Hessian fly (Mayetiola destructor). Flag leaves of Guymon at the boot stage are green, recurved, twisted, and non-waxy. Spikes are white-chaffed, awned, oblong, lax, and recurved at harvest-maturity. Kernels are white, hard-textured, elliptical, and they have a midwide, shallow crease, angular cheeks, and large germ. Milling quality is good, dough mixing tolerance is average, and bake loaf volume is excellent.