Release of 19 waxy winter wheat germplasm, with observations on their grain yield stability

“Waxy” wheats (Triticum aestivum L.) produce endosperm starch devoid, or nearly so, of amylose. Waxy starch consists only of amylopectin, imparts unique cooking properties, and serves as an efficient substrate for the production of modified food starches. To expand the genetic variation of waxy wheats useful to Great Plains breeding programs, the USDA-ARS, in cooperation with the University of Nebraska, developed and released 19 waxy winter wheats (Reg. No. GP-1003, PI 677864 to Reg. No. GO-1021, PI 677882). Three of the waxy germplasm lines have soft endosperm texture; the remaining 16 lines have hard-textured grain. The grain yields of six of the waxy winter wheat germplasm lines were not significantly different from the highest yielding nonwaxy cultivar (‘Freeman’). All but four waxy germplasm lines had grain yields statistically equal to that of the waxy winter wheat cultivar Mattern. Grain yield stability (or response to changing environments) of the waxy germplasm lines demonstrated similar trends to those of the nonwaxy controls. Grain yield observations and responses to changing production potentials argue against any yield drag associated with waxy starch and indicate potential for the development of additional and competitive cultivars.