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The aim of this study is to investigate the macrolide resistance rate and molecular type with multiple-locus variable-number tandem-repeat analysis (MLVA) of Mycoplasma pneumoniae of Beijing in 2016 in pediatric patients. Real-time quantitative polymerase chain reaction (PCR) was used to identify M. pneumoniae, and MLVA was performed. The domain V of the 23S rRNA was sequenced to detect macrolide-resistant point mutations. We also investigated the activities of antibiotics against M. pneumoniae isolates in vitro. The PCR detection rate of M. pneumoniae in children in Beijing was 40%, and the macrolide resistance rate was 66%. The A2063G mutation in the 23S rRNA V region is the dominant mutation (137/146, 93.84%), whereas the A2064G mutation is rare (9/146, 6.16%). Seventy-three samples were typed successfully by MLVA typing, including 86.3% (63/73) were MLVA type 4-5-7-2, and 13.7% (10/73) were MLVA type 3-5-6-2. No other types were found. No strains were resistant to levofloxacin or tetracycline. In 2016, a specific decrease in the macrolide resistance rate occurred in Beijing. The detection rate and macrolide resistance rate of outpatients are lower than those of inpatients. The A2063G mutants M. pneumoniae have high levels of resistance to erythromycin and azithromycin. The primary MLVA type is 4-5-7-2, followed by 3-5-6-2. No other MLVA types were detected. No strains resistant to tetracycline or levofloxacin were found in vitro. [ABSTRACT FROM AUTHOR]

Quail is extensively reared in China for characteristic of quick growth, small fodder consumption, early sexual maturity, high egg output and short production period. In this study, the SNP markers in 5' regulation regions of cytogenin gene (MyoG) among China yellow quail, Beijing white quail and Korean quail were detected by PCR-SSCP method. Moreover, correlations of MyoG 5' regulation regions with carcass characteristics of quail were analyzed. Results demonstrated thatin egg quail group, six genotypes were detected in Locus A in the control region of MyoG 5', including AA, BB, CC, AB, AC and BC. The highest frequencies of CC in China yellow quail, Beijing white quail and Korean quail were 0.323, 0.366 and 0.444, respectively. A total of 9 genotypes were detected in locus B in egg quail group, which were AA, BB, CC, DD, EE, AB, AC, AD and AE. AA showed the highest frequency in China yellow quail, Beijing white quail and Korean quail, which were 0.493, 0.385 and 0.406, respectively. There was significant correlation between locus A and leg muscle rate of egg quail (P<0.05). Locus B presented significant correlations with carcass net weight, leg muscle weight, dressing percentage, whole net carcass rate and heart rate (P<0.05). Loci A and B in the control region of MyoG 5' can be used as the molecular marker of carcass characteristics of egg quails during marker assisted selection. [ABSTRACT FROM AUTHOR]

This study was carried out to evaluate growth and development and difference between size and weights of three quail species namely China yellow quail, Beijing white quail and Korea quail. Various parameters in respect of these species like shank length, chest width, chest depth, breastbone length, shank circumference, body length, daily weight gain and weight were recorded under similar feeding conditions. The data so obtained was analysed statistically using SPSS. It was revealed that the body weight, shank length, chest width, chest depth, breastbone length, body length, shank circumference and daily gain of Korea quail are significantly higher (P≤0.05) than those of China yellow quail and Beijing white quail. It was concluded the Korea quail grows fastest, followed by China yellow quail and Beijing white quail, successively. [ABSTRACT FROM AUTHOR]

Powdery mildew, caused by Blumeria graminis f. sp. tritici, is a major fungal disease in common wheat ( Triticum aestivum L.) worldwide. The Chinese winter wheat cultivar Lumai 21 has shown good and stable adult plant resistance for 19 years. The aim of this study was to map quantitative trait loci (QTLs) for resistance to powdery mildew in a population of 200 F3 lines from the cross Lumai 21/Jingshuang 16. The population was tested for powdery mildew reaction in Beijing and Anyang in the 2005–2006 and 2006–2007 cropping seasons, providing data for 4 environments. A total of 1,375 simple sequence repeat (SSR) markers were screened for associations with powdery mildew reactions, initially in bulked segregant analysis. Based on the mean disease values averaged across environments, broad-sense heritabilities of maximum disease severity and area under the disease progress curve were 0.96 and 0.77, respectively. Three QTLs for adult plant resistance were detected by inclusive composite interval mapping. These were designated QPm.caas-2BS, QPm.caas-2BL and QPm.caas-2DL, respectively, and explained from 5.4 to 20.6% of the phenotypic variance across environments. QPm.caas-2BS and QPm.caas-2DL were likely new adult plant resistance QTLs flanked by SSR markers Xbarc98– Xbarc1147 and Xwmc18– Xcfd233, respectively. These markers could be useful for improving wheat powdery mildew resistance in breeding programs. [ABSTRACT FROM AUTHOR]

Adult-plant resistance (APR) is an effective means of controlling powdery mildew in wheat. In the present study, 406 simple-sequence repeat markers were used to map quantitative trait loci (QTLs) for APR to powdery mildew in a doubled-haploid (DH) population of 181 lines derived from the cross Bainong 64 x Jingshuang 16. The DH lines were planted in a randomized complete block design with three replicates in Beijing and Anyang during the 2005-06 and 2007-08 cropping seasons. Artificial inoculations were carried out in Beijing using the highly virulent Blumeria graminis f. sp. tritici isolate E20. Disease severities on penultimate leaves were scored twice in Beijing whereas, at Anyang, maximum disease severities (MDS) were recorded following natural infection. Broad-sense heritabilities of MDS and areas under the disease progress curve were 0.89 and 0.77, respectively, based on the mean values averaged across environments. Composite interval mapping detected four QTLs for APR to powdery mildew on chromosomes 1A, 4DL, 6BS, and 7A; these were designated QPm.caas-lA, QPm.caas-4DL, QPm.caas-6BS, and QPm.caas-7A, respectively, and explained 6.3 to 22.7% of the phenotypic variance. QTLs QPm.caas-4DL and QPm.caas-6BS were stable across environments with high genetic effects on powdery mildew response, accounting for 15.2 to 22.7% and 9.0 to 13.2% of the phenotypic variance, respectively. These results should be useful for the future improvement of powdery mildew resistance in wheat. [ABSTRACT FROM AUTHOR]