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□ Fertilization plays an important role in soil fertility and rice yield. A long-term (1990–2006) field experiment was conducted at a typical subtropical hilly agriculture region in south central China. The objectives of this study are to investigate the effects of long-term fertilizations on i) accumulations and distributions of soil carbon (C), nitrogen (N) and phosphorus (P) in different sizes of water-stable aggregates (WSA); ii) dynamic change of soil C, N, and P over years; and iii) the rice yield. Application of organic materials (OM), especially in combination with chemical fertilizers, increased soil organic C (SOC), soil total N (NT), and soil total P (PT) concentrations in all sizes of WSA, and they more concentrated in WSA (>1 mm). However, single chemical fertilizers had little impact on SOC and NT. There were significantly positive correlations between SOC and NTin each size of WSA, (r≥0.977, n = 15,P< 0.01). It illuminated that application of organic materials benefited the conservation of soil nitrogen. However, application of organic materials had less impact on PT. Variation of C/P was larger than C/N. PTwas mainly affected by input of phosphorus. Data over years showed that SOC and NTcontinued to rise, whereas PTtended to decline irrespective of treatments. Furthermore, economical chemical fertilizers application combining with green manure and half straw returning (NPKe+ SR) can produce approximate effects on PTas conventional dose of chemical fertilizers (NPKc). Average rice yield of NPKcfor 17 years was 9399 kg ha−1. Compared with NPKc, OM decreased yield by only 4.4%, which indicated that traditional organic fertilization could obtain relatively high yield. NPKe+ SR obtained approximate yield as NPKcdid, which showed that green manure and half amount of straw effectually reduced chemical fertilizers by about one third. [ABSTRACT FROM AUTHOR]

Aim. The complete mitochondrial genome sequence of a newly discovered vole, Proedromys liangshanensis (Rodentia: Cricetidae: Arvicolinae), was determined. Results. The mitogenome of P. liangshanensis is 16,296  bp in length. As with most other mammals, it contains the same gene order and an identical number of genes or regions, including 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and one putative control region. The A++T content of the control region is 58.2%, the lowest proportion detected so far in Myomorpha. To confirm the phylogenetic position of P. liangshanensis, we carried out phylogenetic analyses based on complete mitochondrial genomic data using Bayesian, maximum parsimony, and maximum likelihood methods. Conclusion. All results revealed that P. liangshanenis is sister to Microtus. Although the results do not bear light on the validity of the genus Proedromys, based on the morphological characters, we suggest that Proedromys is an independent genus of equal rank to the genus Microtus. [ABSTRACT FROM AUTHOR]

A vole species, Proedromys liangshanensis Liu, Sun, Zeng and Zhao, 2007 (Rodentia: Arvicolinae), which is endemic to the Liangshan Mountains, Sichuan, China, was reported in 2007. The species is restricted to a narrow range because of its weak dispersal ability and habitat specificity, and only lives in fir and spruce forests with abundant grass. In this study, the genetic diversity and phylogeographical structure of 42 P. liangshanensis were examined based on analysis of a partial mitochondrial DNA control region. The results revealed low genetic diversity in the P. liangshanensis populations. Twelve nucleotide haplotypes were defined in the 42 collected individuals, and were divided into two major phylogenetic clades, which were obviously related to geographic pattern. Estimates of gene flow (Nm = 0.09) also revealed a genetic divergence between the Jinyang and Meigu populations. Species-specific traits, habitat specificity and geographic events contributed to the genetic divergence of the new vole. [ABSTRACT FROM AUTHOR]

The first complete mitochondrial genome of the large white-bellied rat ( Niviventer excelsior) was sequenced and annotated in order to provide a source of phylogenetic characters including an assessment of gene order arrangement. The mitochondrial genome sequence (16,298 bp) of N. excelsior contains 13 protein-coding, 2 rRNA and 22 tRNA genes as well as 1 typical control region (D-Loop), which are shared by other mammalian mitochondrial genomes. The codon usage also followed the typical vertebrate pattern except for an unusual CCA stop codon, which was termination codon of Cyt b. The 16 nucleotide insertion was detected in the central conserved domain of d-Loop. The 12 heavy-strand encoded protein-coding genes were used to reconstruct the phylogenetic relationships by the Bayesian inference and maximum likelihood methods. Topologies revealed that N. excelsior clustered together with the species in genus Rattus, indicating their closer phylogenetic relationship. [ABSTRACT FROM AUTHOR]