Evaluation location: Iowa, United States
On April 16, 2007, Calendula seeds were sown from distribution lots of accessions available for distribution at the USDA-ARS North Central Regional Plant Introduction Station (NCRPIS), Iowa State University, Ames, IA. Seedlings were cultivated in the greenhouse until approximately the 5-leaf stage, when they were hardened off and then transplanted by hand on May 15, 2007 by hand to a field at the NCRPIS farm (42 degrees 00' 40"N, 93 degrees 39' 33"W). Seedlings were grouped by accession in 10-plant rows, with 2 rows per accession (inventory lots 07ncax01 and 07ncax02) whenever possible. Plants were spaced 45-cm apart within rows and 214-cm apart between rows in a randomized block design with two blocks. Observations were taken on these plants between June 5 and August 10, 2007 for the following descriptors: anther color, bloom quality, capitulum depth, capitulum diameter, cut stem length, determinant seed maturity/quality, days to first flowering, date of first flowering, days to peak flowering, date of peak flowering, flower diameter, flower profusion, flowering percentage, ray flower purple tip, growth habit, lodging, peduncle length, plant height, plant width, ray length, ray width, minimum ray number, maximum ray number, ray shape, recommended use, seed retention, ray flower color, disc flower color, and aster yellows resistance. Observations were discontinued after August 10, 2007 because of a combination of heat and wind stress, aphid feeding, and increasing occurrence of aster yellows. Values presented are averages of the two replicated plots.