A set of 184 recombinant inbred lines (RILs) derived from soybean vars. Kefeng No.1 x Nannong 1138-2 was used to construct a genetic linkage map. The two parents exhibit contrasting characteristics for most of the traits that were mapped. Using restricted fragment length polymorphisms (RFLPs), simple sequence repeats (SSRs) and expressed sequence tags (ESTs), we mapped 452 markers onto 21 linkage groups and covered 3595.9 cM of the soybean genome. All of the linkage groups except linkage group F were consistent with those of the consensus map of Cregan et al. (1999). Linkage group F was divided into two linkage groups, F1 and F2. The map consisted of 189 RFLPs, 219 SSRs, 40 ESTs, three R gene loci and one phenotype marker. Ten agronomic traits-days to flowering, days to maturity, plant height, number of nodes on main stem, lodging, number of pods per node, protein content, oil content, 100-seed weight, and plot yield-were studied. Using winqtlcart, we detected 63 quantitative trait loci (QTLs) that had LOD>3 for nine of the agronomic traits (only exception being seed oil content) and mapped these on 12 linkage groups. Most of the QTLs were clustered, especially on groups B1 and C2. Some QTLs were mapped to the same loci. This pleiotropism was common for most of the QTLs, and one QTL could influence at most five traits. Seven EST markers were found to be linked closely with or located at the same loci as the QTLs. EST marker GmKF059a, encoding a repressor protein and mapped on group C2, accounted for about 20% of the total variation of days to flowering, plant height, lodging and nodes on the main stem, respectively.

Arctium lappa and A. tomentosum are known medicinal plants in China. The complete chloroplast genomes from A. lappa and A. tomentosum were sequenced using Illumina sequencing technology. The total genome sizes of the complete chloroplast genomes of A. lappa and A. tomentosum were 152 767 bp and 152 688 bp, respectively, and contained a pair of inverted repeats of the same length (15,181 bp). The small single-copies were 18 584 bp and 18 582 bp, and the large single-copies were 83 821 bp and 83 744 bp, respectively. We identified and annotated 134 and 126 genes from A. lappa and A. tomentosum including, respectively, 90 and 89 protein-coding genes, 36 and 29 tRNAs, and eight rRNAs. A. lappa was found to have 10 tRNAs different from those in A. tomentosum, and A. tomentosum had three tRNAs different from those in A. lappa. There were only two types of simple sequence repeats of two species, mononucleotide and dinucleotide, and the sequences were A and T rich. In addition, the two ways of phylogenetic analysis show that the position of A. lappa and A. tomentosum is consistent within Asteraceae.

ABSTRACT. Fifty-five wild accessions of bermudagrass (Cynodon dactylon) were collected from southwest China (Sichuan, Chongqing, Yunnan, Guizhou, and Tibet), and their genetic diversity was analyzed using simple sequence repeat markers. A total of 267 polymorphic bands were detected with 18 primer combinations. The genetic similarity among the accessions ranged from 0.688 to 0.894 with an average of 0.797. All 55 wild accessions were clustered into 7 ecogeographic groups. Our data showed that the dendrogram was almost in accordance with geographic distribution, and accessions from the same collection sites tended to be clustered into the same group. A genetic differentiation analysis revealed that the percentage of genetic variance was 70.07 and 29.93% within and among groups, respectively. Finally, we discuss the implications of these results for C. dactylon in southwest China.