The effect of interplant distance on the effectiveness of honeycomb selection in spring rye. III. Accumulated results of five selection cycles

The effect of interplant distance on the efficiency of mass selection was s tudied by performing five cycles of honeycomb selection at two interplant d istances (d), i.e. d = 100 cm (low plant density, implying absence of inter plant competition) and d = 15 cm (high plant density, implying presence of intergenotypic competition). The offspring of plants selected either at low or at high plant density were compared, both at high plant density and at low plant density, with the original population (in fact: offspring of plan ts taken at random from this population). At high plant density offspring of plants selected at high density performe d better than the original population for most of the characters recorded o n a per plant basis. At low plant density offspring of plants selected eith er at high or at low density performed better than the original population for the characters recorded on a per plant basis. The selections differed, however, significantly from each other: the offspring of plants selected at low density performed better. As the latter did not occur at high density genotype x density interaction was indicated. It is concluded that mass selection should be applied at the plant density used in commercial practice.