Interspecific hybrids and possible phylogenetic relations in grain amaranths

Abstract

Phylogenetic relations among the three species in grain amaranth need investigation to provide information for breeding experiments germplasm conservation efforts, and decision on evolutionary patterns in the grain types. Hybrid development from crosses between species was studied to find out genetic relationship between them. Interspecific crosses were made among Amaranthus hypochondriacus, A. caudatus and A. cruentus in the glasshouse. The F1 plants were relatively easy to obtain but had low pollen fertility (10.3–15.1%) and low seed set. A few of these hybrids did not produce seeds. Only a few F1 seeds obtained in crosses between A. cruentus and A. caudatus. All the F1 plants from these crosses died at the seedling stage. Crosses between A. cruentus and A. hypochondriacus produced few seeds. Most of the F1 plants obtained from the seeds died at the seedling stage with only four plants growing to maturity but were sterile. Based on hybrid development, it was suggested that A. hypochondriacus and A. caudatus were genetically closer than the other two combinations of species studied. A. cruentus seemed to be genetically closer to A. hypochondriacus than it was to A. caudatus.