Male sterility is useful for plant breeders to cross-pollinate between plants, especially plants with many small flowers. Cytoplasmic male sterility (CMS) is a way of managing male sterility to get populations of 100% male sterile plants to use as females in plant crossing. In many crops especially sunflowers, and sorghum, most of the cultivars are F1 hybrids made with CMS to benefit from hybrid vigor (heterosis) and thereby improve performance over open pollinated cultivars (Kim and Zhang, 2018). CMS may someday be used to produce improved seeds for amaranths as is already done with those crops (Peters and Jain, 1987; Brenner, 2020). We in the United States National Plant Germplasm System are assembling useful germplasm and information for crop improvement including CMS amaranths (GRIN, 2020a).