RESUMEN
The mutualistic network of plant-pollinator also involves interspecific pollination caused by pollinator sharing. Plant-pollinator networks are commonly based on flower visit observations, which may not adequately represent the actual pollen transfer between co-flowering plant species. Here, we compared the network structure of plant-pollinator interactions based on flower visits (FV) and pollen loads (PL) on the bodies of pollinators and tested how the degree of pollinator sharing in the two networks affected heterospecific pollen transfer (HPT) between plant species in a subalpine meadow. The FV and PL networks were largely overlapped. PL network included more links than FV network. The positions of plant and pollinator species in the FV and PL networks were positively correlated, indicating that both networks could detect major plant-pollinator interactions. The degree of pollinator sharing, based on either the FV or the PL network, positively influenced the amount of heterospecific pollen transferred between plant species pairs. However, the degree of pollinator sharing had a low overall explanatory power for HPT, and the explanatory powers of the FV and PL networks were similar. Overall, our study highlights the importance of FV and PL for understanding the drivers and outcomes of plant-pollinator interactions, as well as their relevance to HPT.
RESUMEN
The complete mitochondrial genome of Heliconius pachinus has been reconstructed from the whole-genome Illumina sequencing data. The circular genome is 15,369 bp in length, and comprises the typical components: 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs) and 1 D-loop region. PCGs are mostly initiated with either the ATN codons (COII, COIII, Cytb, ND2, ND3, ND4, ND4L, ND5, ND6, ATP6 & ATP8) or the TTG codon (ND1); the COI gene may use the unusual CGA as its initiation codon, as suggested for other lepidopteran species. Some PCGs harbor TAG (ND3) or incomplete termination codon T (COI, COII & ND4), while the others use TAA as their termination codons. The nucleotide composition is highly asymmetric (39.2% A, 42.0% T, 7.7% G, 11.1% C) with an overall GC content of 18.8%.
Asunto(s)
Mariposas Diurnas/genética , ADN Mitocondrial/genética , Genoma Mitocondrial/genética , Mitocondrias/genética , Animales , Composición de Base/genética , Secuencia de Bases , Codón Iniciador/genética , Codón de Terminación/genética , ADN Intergénico/genética , Tamaño del Genoma/genética , ARN Ribosómico/genética , ARN de Transferencia/genética , Análisis de Secuencia de ADNRESUMEN
Saruma henryi Oliv. (Aristolochiaceae) is an endangered herb endemic to China. In this study, chloroplast microsatellites (cpSSRs) and sequences of the atpB-rbcL intergenic spacers were employed to reveal its genetic diversity and phylogeographic patterns. We detected high within-species genetic diversity (H(T)=0.939 for cpSSR; H(T)=0.862 for atpB-rbcL) and pronounced among-population genetic differentiation (H(S)=0.182, G(ST)=0.811, R(ST)=0.9, F(ST)=0.93 for cpSSR; H(S)=0.238, G(ST)=0.724, N(ST)=0.758, F(ST)=0.79 for atpB-rbcL) with a strong phylogeographic pattern (R(ST)>G(ST), P<0.01 for cpSSR; N(ST)>G(ST), U=0.25 for atpB-rbcL). Eleven haplotypes were distinguished by cpSSRs and atpB-rbcL intergenic spacers, respectively. The molecular phylogenetic data, together with the geographic distribution of the haplotypes, suggested the existence of multiple localized glacial refugia in Mts. Qinling, eastern Mts. Bashan and the southeastern edge of Yunnan-Guizhou Plateau. Nested clade analysis (NCA) and population genetic analyses supported the limited gene flow (caused by low dispersal capacity and complex topography of its habitats) as the major factor responsible for the strong population differentiation and phylogeographic pattern. Past fragmentation and allopatric fragmentation were inferred as important processes responsible for the modern phylogeograhpic pattern. In addition, contiguous range expansions occurred in western Mts. Qinling and eastern Mts. Bashan.