Field evaluation of an Amaranthus genetic resource collection in China

A total of 229 genotypes of 20 Amaranthus species from the United States De partment of Agriculture - Agricultural Research Service (USDA - ARS) Nation al Plant Germplasm Amaranth Collection was evaluated in field experiments i n Beijing and Wuhan, China, in 1994. Agronomic traits, including plant heig ht, maturity, leaf number and color, stem color, seed color, branch number, 1000-grain-weight, yield per plant, and resistance to stresses (including diseases) were measured. The results indicated: 1. Many of the species were sensitive to daylength; 2. Cultivated genotypes generally had higher grain yield but were more seriously affected by diseases than non-cultivated spe cies; 3. There was wide diversity in agronomic traits among Amaranthus spec ies and among genotypes within the same species, and several genotypes were identified that appeared to carry favorable agronomic traits of immediate use in cultivar improvement; 4. For introduction of genotypes for use in pl ant breeding in China, selection should be partially based on matching the climates of the location of origin and the target area for production.