Flowering Characteristics of Cicer Milkvetch Clones and Their Polycross Progenies 1

The flowering requirements of cicer milkvetch ( Astragalus cicer L.) are not known. Many plants do not flower in a greenhouse environment or during the seedling year in the field. The primary objective of this study was to determine the relationship between the flowering characteristles of 34 parental clones in the greenhouse and field and the performance of their polycress progenies for similar characters in the field. All clones flowered during the first growth period in the greenhouse when brought from the field in late December. However, flowering did not occur on the regrowth of some clones in the greenhouse. Date of flowermg in the field during the year of establishment was more highly correlated to date of flowering on the regrowth(r = 0.68) than on the first growth (r = −0.12) of these clones in the greenhouse. After going through the winter in the field, all clones flowered profusely the following spring. In the field during the seedling year the percent of nonflowering plants within polycross progenies ranged from 2 to 51. After going through the winter in the field, all plants in 13 of 34 progenies flowered the following spring; only 3.5% of the total population did not flower. On the regrowth in the second year the percent of nonflowering, plants within progenies ranged, from 4 to 40, which was similar to that in the seedling year. Percentage of nonflowering plants was significantly correlated with date of flowering during all three growth periods. In the field, date of flowering for the parental clones during the year of establishment was significantly correlated with date of flowering of their polycross progenies in the seedling year (r=0.61). Both the greenhouse and field data indicated that some genotypes did not require exposure to low temperature for flower induction whereas other genotypes did. The low temperature requirements for such genotypes remain to be determined.