The Jianchang horse is a small horse breed that is popular in China, particularly in the southwest regions of China. The Jianchang horse breed is from the mountainous regions of Liangshan in the Sichuan Province, and has excellent mountainous adaptation when compared to other horses. It was domesticated to fulfill local people's needs for riding and transport across mountainous regions over 1000 years ago.Jianchang horses are well known to be quiet, hardy, powerful, and not vulnerable to environmental stress, these attribute to work effortlessly in the mountainous regions of China. As shown in Figure 1, it is typically small with an average height of 110 cm to 120 cm and a weight of 180 kg to 250 kg. It has small ears and head, long and dense bristle, and caudal seta and mane. It has a sloped croup, slender but well-developed legs, and hard hooves. Its hair is mainly in the bay color, but other colors like black appear occasionally [1].The sequence diversity of the mtDNA control region has been used for analyzing the origin and diversification of domestic horses [2][3][4]. It is widely believed that horses were domesticated from one or several ancestral horse populations [5][6][7]. However, information on its origin and evolution is still limited. In this study, we generate complete mitochondrial genome sequence of Jianchang horse and the complete mtDNA mitochondrial genome was used for phylogenetical analysis. The diversity and origin of the domestic horses in China by mtDNA D-loop have been reported [8]. However, the mtDNA D-loop sequence was not fully show the diversity and origin of the Jianchang horse breeds in the southwest regions of China. It is the first time that molecular evidences were provided for the origin of the Jianchang horse population. AbstractThe Jianchang horse (Equus caballus), a famous breed in the southwest regions of China, has excellent mountainous adaptation. The domestic Jianchang horse is popular in China, but information on its origin and evolution is still limited. In this study, we generate complete mitochondrial genome sequences of Jianchang horse. It is 16,614 bp in length, containing 22 transfer RNA genes, 2 ribosomal RNA genes, 13 protein-coding genes and and a noncoding control region (D-loop region). And it was found to be similar to other horse mitochondrial genomes. However, there were 105 nucleotide substitutions in the 13 protein-coding genes. The phylogenetic tree analysis was shown that Jianchang horse was significantly clustered as the clade with Debao and Yunnan horse. This genomic data provides useful information for further studies on the genetic diversity and origin of the Jianchang horse population.

ABSTRACT. China is one of the principal origins of ponies in the world. We made a comprehensive analysis of genetic diversity and population structure of Chinese ponies based on 174 animals of five indigenous Chinese pony breeds from five provinces using 13 microsatellite markers. One hundred and forty-four alleles were detected; the mean number of effective alleles among the pony breeds ranged from 5.38 (Guizhou) to 6.78 (Sichuan); the expected heterozygosity ranged from 0.82 (Guizhou) to 0.85 (Debao, Sichuan). Although abundant genetic variation was found, the genetic differentiation was low between the ponies, with 6% total genetic variance among the different breeds. All the pairwise F ST values were significant; they varied from 0.0424 for the Sichuan-Yunnan pair to 0.0833 for the Guizhou-Sichuan pair. All five pony breeds deviated from Hardy-Weinberg equilibrium, except the Yunnan pony. Phylogenetic trees of the five pony breeds based on genetic distances were constructed using a neighbor-joining method. The Sichuan and Yunnan ponies were ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 11 (3): 2629-2640 (2012) L.X. Xu et al. 2630 grouped into the same branch, with a high bootstrap support value (97%). Guizhou and Ningqiang ponies were clustered into the same branch with a bootstrap value of 56%, whereas the Debao pony was placed in a separate group, with a bootstrap value of 56%. This grouping pattern was supported by genetic structure analysis.

The genetic diversity and population structure of 38 commercial accessions of double-flowered amaryllis (Hippeastrum hybridum) from the Netherlands and South Africa were evaluated using sequence-related amplified polymorphism (SRAP) markers. Thirty SRAP primer pairs produced 294 loci, of which 263 (89.16%) were polymorphic. A relatively high level of genetic diversity was observed, with estimates of Nei’s diversity index (H) and the Shannon information index (I) of 0.2719 and 0.4158, respectively. Additional genetic distance- and STRUCTURE-based analyses clustered all accessions into two or four subgroups based mostly on origin or color. The genetic differentiation between/among countries and inferred groups was significant, with Fst values ranging from 0.083-0.194%. Accessions from the Netherlands showed higher genetic variation than those from South Africa. Several accessions, such as Aphrodite, are recommended for future programs employing selective hybridization with the goal of expanding the color range. The results of the present study provide appropriate information applicable to designing effective breeding programs for double-flowered amaryllis.

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