As an economic crop, pepper satisfies people's spicy taste and has medicinal uses worldwide. To gain a better understanding of Capsicum evolution, domestication, and specialization, we present here the genome sequence of the cultivated pepper Zunla-1 (C. annuum L.) and its wild progenitor Chiltepin (C. annuum var. glabriusculum). We estimate that the pepper genome expanded ∼0.3 Mya (with respect to the genome of other Solanaceae) by a rapid amplification of retrotransposons elements, resulting in a genome comprised of ∼81% repetitive sequences. Approximately 79% of 3.48-Gb scaffolds containing 34,476 protein-coding genes were anchored to chromosomes by a high-density genetic map. Comparison of cultivated and wild pepper genomes with 20 resequencing accessions revealed molecular footprints of artificial selection, providing us with a list of candidate domestication genes. We also found that dosage compensation effect of tandem duplication genes probably contributed to the pungent diversification in pepper. The Capsicum reference genome provides crucial information for the study of not only the evolution of the pepper genome but also, the Solanaceae family, and it will facilitate the establishment of more effective pepper breeding programs.de novo genome sequence | genome expansion | Solanaceae evolution

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Integrating theories of proactive motivation, team innovation climate, and motivation in teams, we developed and tested a multilevel model of motivators of innovative performance in teams. Analyses of multisource data from 428 members of 95 research and development (R&D) teams across 33 Chinese firms indicated that team-level support for innovation climate captured motivational mechanisms that mediated between transformational leadership and team innovative performance, whereas members' motivational states (role-breadth self-efficacy and intrinsic motivation) mediated between proactive personality and individual innovative performance. Furthermore, individual motivational states and team support for innovation climate uniquely promoted individual innovative performance, and, in turn, individual innovative performance linked team support for innovation climate to team innovative performance.

Mosquitoes are insects of the Diptera, Nematocera, and Culicidae families, some species of which are important disease vectors. Identifying mosquito species based on morphological characteristics is difficult, particularly the identification of specimens collected in the field as part of disease surveillance programs. Because of this difficulty, we constructed DNA barcodes of the cytochrome c oxidase subunit 1, the COI gene, for the more common mosquito species in China, including the major disease vectors. A total of 404 mosquito specimens were collected and assigned to 15 genera and 122 species and subspecies on the basis of morphological characteristics. Individuals of the same species grouped closely together in a Neighborhood-Joining tree based on COI sequence similarity, regardless of collection site. COI gene sequence divergence was approximately 30 times higher for species in the same genus than for members of the same species. Divergence in over 98% of congeneric species ranged from 2.3% to 21.8%, whereas divergence in conspecific individuals ranged from 0% to 1.67%. Cryptic species may be common and a few pseudogenes were detected.

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The sequences of the full set of pepper genomes including nuclear, mitochondrial and chloroplast are now available for use. However, the overall of simple sequence repeats (SSR) distribution in these genomes and their practical implications for molecular marker development in Capsicum have not yet been described. Here, an average of 868,047.50, 45.50 and 30.00 SSR loci were identified in the nuclear, mitochondrial and chloroplast genomes of pepper, respectively. Subsequently, systematic comparisons of various species, genome types, motif lengths, repeat numbers and classified types were executed and discussed. In addition, a local database composed of 113,500 in silico unique SSR primer pairs was built using a homemade bioinformatics workflow. As a pilot study, 65 polymorphic markers were validated among a wide collection of 21 Capsicum genotypes with allele number and polymorphic information content value per marker raging from 2 to 6 and 0.05 to 0.64, respectively. Finally, a comparison of the clustering results with those of a previous study indicated the usability of the newly developed SSR markers. In summary, this first report on the comprehensive characterization of SSR motifs in pepper genomes and the very large set of SSR primer pairs will benefit various genetic studies in Capsicum.

The Gy14 cucumber (Cucumis sativus) is resistant to oomyceteous downy mildew (DM), bacterial angular leaf spot (ALS) and fungal anthracnose (AR) pathogens, but the underlying molecular mechanisms are unknown. Quantitative trait locus (QTL) mapping for the disease resistances in Gy14 and further map-based cloning identified a candidate gene for the resistant loci, which was validated and functionally characterized by spatial-temporal gene expression profiling, allelic diversity and phylogenetic analysis, as well as local association studies. We showed that the triple-disease resistances in Gy14 were controlled by the cucumber STAYGREEN (CsSGR) gene. A single nucleotide polymorphism (SNP) in the coding region resulted in a nonsynonymous amino acid substitution in the CsSGR protein, and thus disease resistance. Genes in the chlorophyll degradation pathway showed differential expression between resistant and susceptible lines in response to pathogen inoculation. The causal SNP was significantly associated with disease resistances in natural and breeding populations. The resistance allele has undergone selection in cucumber breeding. The durable, broad-spectrum disease resistance is caused by a loss-of-susceptibility mutation of CsSGR. Probably, this is achieved through the inhibition of reactive oxygen species over-accumulation and phytotoxic catabolite over-buildup in the chlorophyll degradation pathway. The CsSGR-mediated host resistance represents a novel function of this highly conserved gene in plants.