The major histocompatibility complex (MHC) is highly polymorphic and plays a central role in the vertebrate immune system. Despite its functional consistency, the MHC genomic structure differs substantially among organisms. In birds, the MHCs of Galliformes and the Japanese crested ibis (Pelecaniformes) are well-characterized, but information about other avian MHCs remains scarce. The Oriental stork (Ciconia boyciana, order Ciconiiformes) is a large endangered migrant. The current Japanese population of this bird originates from a few founders; thus, understanding the genetic diversity among them is critical for effective population management. We report the structure and polymorphisms in C. boyciana MHC. One contig (approximately 128 kb) was assembled by screening of lambda phage genomic library and its complete sequence was determined, revealing a gene order of COL11A2, two copies of MHC-IIA/IIB pairs, BRD2, DMA/B1/B2, MHC-I, TAP1/2, and two copies each of pseudo MHC-I and TNXB. This structure was highly similar to that of the Japanese crested ibis, but largely different from that of Galliformes, at both the terminal regions. Genotyping of the MHC-II region detected 10 haplotypes among the six founders. These results provide valuable insights for future studies on the evolution of the avian MHCs and for conservation of C. boyciana.

Microsatellite analysis was used to characterize the patterns of pollen flow in a 150 m × 70 m quadrat containing 18 flowering trees of Rhododendron metternichii Sieb. et Zucc. var. hondoense Nakai. Using six microsatellite genetic markers and exclusion analysis, we determined the paternal trees of 216 seedlings germinated from five fruits produced by four adults. Each fruit was pollinated by a small number of largely adjacent trees, but 20–30% of pollen came from outside the quadrat. Adult trees that produced many flowers had a high self‐pollination rate. A directional flow of pollen from late‐blooming trees to early ones was observed.

An ecological feature of Rhododendron metternichii var. hondoense is its great morphological variation. Individuals may have only one erect stem or may have multiple creeping stems, implying that some of them recruit vegetatively. Aims of this study are to ascertain whether a population of R. metternichii var. hondoense consists of clonal plants, and to evaluate relative importance of sexual and asexual recruitments in regard to its conservation. Six microsatellite loci were analyzed in two populations growing in different habitats. One was in a mesic valley consisting of many sprouting and creeping individuals with few seedlings, and the other on a mountain ridge consisting of single stem individuals with many seedlings. Sufficient polymorphisms were found to be present even in the mesic valley population that consisted of many sprouting and creeping stems, indicating that in the past the population was maintained by both sexual and asexual reproduction. The scarcity of seedlings at the mesic valley was due to dense litter cover and low bryophyte mat cover which may be caused by changes in traditional management systems. Required conservation measures are discussed based on these results.

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