Abstract
Veronicastrum sibiricum var. zuccarinii (Plantaginaceae) is an endangered perennial herb native to semi-natural grasslands in southern Korea and Kyushu, Japan. To elucidate the genetic status of V. sibiricum var. zuccarinii in the Aso region of Kyushu, in which relatively large populations still remain, we analyzed seven populations using five novel microsatellite markers. Each population of V. sibiricum var. zuccarinii has a maintained moderate level of genetic diversity (mean H E = 0.596, mean N A = 5.6, and mean AR = 4.7). Pairwise F ST indicated significant genetic differentiation between all population pairs (0.065−0.309). The semi-natural grasslands in the Aso region have decreased in area over the past decades. Thus, habitat fragmentation may be causing genetic differentiation among populations of V. sibiricum var. zuccarinii. Although the populations of this variety have maintained a moderate degree of genetic diversity, the dynamics of gene flow among them should be continuously monitored.