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Post-anthesis photoassimilation is very important for wheat ( Triticum aestivum L.) grain filling. The aim of the present study was to map quantitative trait loci (QTL) for post-anthesis dry matter accumulation (DMA). A set of 120 doubled haploid (DH) lines, derived from winter wheat varieties Hanxuan 10 and Lumai 14, was grown under field conditions in two consecutive growing seasons during 2002–2004 in Beijing. Post-anthesis DMA per culm and related traits, including flag leaf greenness (FLG) and flag leaf weight (FLW; dry weight per flag leaf) at flowering, and grain weight per ear (GWE) were investigated. All traits segregated continuously in the DH population in both trials. The DMA was significantly and positively correlated with GWE, with the correlation coefficients being 0.79 and 0.66 in the 2002–2003 and 2003–2004 growing seasons (both P < 0.01), suggesting the importance of DMA in grain filling. Further correlation analysis showed that FLW was more closely correlated with DMA and GWE than FLG in both growing seasons, indicating that FLW was more important than FLG in influencing DMA and GWE. In total, 30 QTLs for these four traits were mapped and distributed on 10 chromosomes. Phenotypic variations explained by an individual QTL were in the range 5.8%–21.3%, 5.9%–17.2%, 5.1%–18.1%, and 5.6%–16.2% for FLG, FLW, DMA, and GWE, respectively. Eight QTLs for DMA were detected, of which four (on chromosome arms 2AS, 4BL, 5AS, and 7AS) were linked with QTLs for GWE; two (on chromosome arms 5BL and 7BL) coincided with QTLs for FLW. These results may provide useful information for developing marker-assisted selection for the improvement of DMA. (Managing editor: Wei Wang) [ABSTRACT FROM AUTHOR]

Background: Babesiosis is an emerging tick-borne zoonotic infectious disease. Babesia microti is responsible for most cases of human babesiosis globally. It is important to investigate the prevalence of B. microti in the mammalian host population of a specific region in order to elucidate mechanisms of pathogen transmission and to define geographic areas where humans face the greatest risk of exposure. The aim of this study is to understand the prevalence and genotypes of B. microti in the small mammals that are found in Beijing, China. Methods: We trapped small mammals from all of the 16 urban, suburban, and outer suburban districts of Beijing during the years 2014, 2017 and 2018. Genomic DNA was extracted from the heart tissues individually and the Babesia 18S rRNA gene was detected by PCR. The genotypes of B. microti were identified based on sequence alignments and phylogenetic analysis. The morphology of the parasites was observed under light microscopy. The risk factors were analyzed statistically based on both univariate analyses and multivariate logistic regression. Results: A total of 1391 small mammals were collected. Positive infection of B. microti was detected in 12.1% (168/1391) of small mammals from 15 out of the 16 districts. Both Kobe-type and U.S.-type B. microti, accounting for 9.5% and 2.7%, respectively, were identified. Classic diverse morphologic forms of B. microti were observed. Specific types of ecological habitats including shrub areas, broad-leaved forest, and cropland were revealed to be risk factors associated with B. microti infection. Conclusions: This study demonstrated the wide prevalence of B. microti infection in eight species of small mammals in Beijing, with Kobe-type more prevalent than U.S.-type. This study provides fundamental information for the development of informed prevention and control measures by public health authorities; the data gathered indicates a need for further monitoring of both clinical diseases in individuals presenting with babesiosis-like symptoms, as well as the infection status of ticks in high risk areas. [ABSTRACT FROM AUTHOR]