Non-Shattering Grain Amaranth Populations

SHATTERING Shattering can cause serious losses in commercial grain production of amaranth (Fitterer et al. 1996). In Nebraska, amaranth grain is harvested after the plants are killed by frost and have dried. The predominant cultivar ‘Plainsman’ is favored partly because it maintains good stem strength after frost has killed it (Baltensperger et al. 1992), however, it does shatter (Fitterer et al. 1996). In certain years, the mature plants must remain standing for weeks before the plants are killed and dry enough to harvest. Each amaranth seed is held in a separate papery utricle. In standard grain production cultivars each utricle has a seam that opens at maturity allowing for circumscissile abscission along the utricle’s equator. Taxonomists including Sauer (1967) have observed that some populations of A. powellii S. Watson have noncircumscissile utricles. A. powellii is a wild and weedy species closely related to the grain amaranths. Noncircumscissile utricles have also been observed infrequently in cultivated amaranths (Hauptli et al. 1980 p. 119; Joshi 1981), and some populations are so indicated in the GRIN database (USDA, ARS 2001). Jain et al. (1986) used the notation, Dh and dh, in A. hypochondriacus, with dh representing a recessive non-circumscissile allele, and Dh representing the dominant circumscissile allele. They noted that the trait has potential for use in breeding programs. Brenner and Hauptli (1990) proposed breeding for non-shattering populations, described the abscission mechanisms, and suggested parental germplasm. The two germplasm releases described herein result from their proposal (Brenner and Hauptli 1990). Hauptli et al. (1980, p. 119) originated the idea of breeding for non-shattering in this way. Two distinct populations were developed because of the need to have cross-compatible germplasm for both grain species important in North America, A. cruentus L. and A. hypochondriacus L. Both of these non-shattering populations are adapted for seed maturity in the Midwestern United States.