Chalkiness is one of the most important agronomic traits in rice breeding,which directly affects the quality of rice seed.In this study,we identified a chalkiness endosperm mutant,chalk-h,from N-methyl-N-nitrosourea(M...Chalkiness is one of the most important agronomic traits in rice breeding,which directly affects the quality of rice seed.In this study,we identified a chalkiness endosperm mutant,chalk-h,from N-methyl-N-nitrosourea(MNU)-induced japonica rice cultivar Hwacheong(HC).Compared with wild type(WT)-HC,chalk-h showed severe chalkiness in the endosperm,yellowish green leaves,as well as reduced plant height.Scanning electron microscopy(SEM)analysis showed that starch grains in the chalk-h mutant were irregular in size and loosely arranged,with large gaps between granules,forming ovoid or orbicular shapes.MutMap analysis revealed that the phenotype of chalk-h is controlled by a single recessive gene LOC_Os11g39670 encoding seryl-tRNA synthetase,which is renamed as CHALK-H.A point mutation occurs in chalk-h on the sixth exon(at nucleotide 791)of CHALK-H,in which adenine(A)is replaced by thymidine(T),resulting in an amino acid codon change from glutamine(Glu)to valine(Val).The chalk-h mutant exhibited a heat-sensitive phenotype from the 3-leaf stage,including yellow-green leaves and reduced pigment content.The transcriptional expression of starch synthesis-related genes was down-regulated in the chalk-h mutants compared to WT-HC at different grain-filling stages.With an increase in temperature,the expression of photosynthesis-related genes was down-regulated in the chalk-h mutant compared to WT-HC.Overexpression of CHALK-H rescued the phenotype of chalk-h,with endosperm and leaf color similar to those of WT-HC.Our findings reveal that CHALK-H is a causative gene controlling chalkiness and leaf color of the chalk-h mutant.CHALK-H is the same gene locus as TSCD11,which was reported to be involved in chloroplast development under high temperature.We suggest that CHALK-H/TSCD11 plays important roles not only in chloroplast development,but also in photosynthesis and starch synthesis during rice growth and development,so it has great application potential in rice breeding for high quality and yield.展开更多
目的建立了一种实时直接分析离子源(direct analysis in real time, DART)结合四极杆/静电轨道离子阱高分辨质谱法(Q-Exactive Orbitrap)快速筛查南美白对虾中磺胺类药物的方法。方法样品经过提取净化后,在离子化温度450℃,栅极电压350...目的建立了一种实时直接分析离子源(direct analysis in real time, DART)结合四极杆/静电轨道离子阱高分辨质谱法(Q-Exactive Orbitrap)快速筛查南美白对虾中磺胺类药物的方法。方法样品经过提取净化后,在离子化温度450℃,栅极电压350 V,样品传输速度0.2 mm/s的DART离子源正离子模式条件下进样,Orbitrap高分辨质谱在-全扫描/数据依赖二级扫描模式下进行定性检测。结果该方法检出限为0.5~2.7μg/kg,满足筛查要求。结论该方法分析速度快,定性准确,无需色谱分离过程,环境友好。展开更多
目的建立一种实时直接分析(direct analysis in real time,DART)离子源结合四极杆/静电轨道离子阱高分辨质谱法(quadrupole/orbitrap high resolution mass spectrometry,Q-Orbitrap HRMS)快速筛查凉茶中非法添加的21种解热镇痛类药物...目的建立一种实时直接分析(direct analysis in real time,DART)离子源结合四极杆/静电轨道离子阱高分辨质谱法(quadrupole/orbitrap high resolution mass spectrometry,Q-Orbitrap HRMS)快速筛查凉茶中非法添加的21种解热镇痛类药物。方法样品经50%甲醇水超声提取,过0.22μm微孔滤膜后,用DART-Q-Orbitrap HRMS测定。DART离子源的样品传输速度为0.2 mm/s、离子化温度为400℃、栅极电压为300 V,扫描模式为正离子模式。结果在全扫描模式下测定目标化合物的一级精密质量数,与理论精密质量数相比,相对误差小于1.65×10^(-6),可实现精准定性;同时建立的21种解热镇痛类药物的二级质谱信息库进一步提高定性分析的准确性。方法筛查限范围为1.00~270.00μg/kg,满足筛查要求。结论该方法具有分析速度快、精准定性、无需冗长色谱分离过程、环境友好等优势,可作为凉茶中21种解热镇痛类非法添加化学药物的高通量筛查和精准定性检测方法。展开更多
The study was designated to explore the physiological mechanism of cold tolerance enhanced by phosphate in rice. An experiment was conducted to investigate the effects of different levels of phosphate fertilizer on co...The study was designated to explore the physiological mechanism of cold tolerance enhanced by phosphate in rice. An experiment was conducted to investigate the effects of different levels of phosphate fertilizer on cold tolerance and its related physiological parameters in rice seedings （chilling-sensitive cv. Changbai 9 and chilling-tolerant cv. Jijing 81） under low temperature stress. At the same time, the identification of cold tolerance was conducted. Compared with the normal temperature treatment, the relative chlorophyll content, photosynthesis rate, Fv/Fm and qP decreased and index of unsaturated fatty acid increased in rice under low temperature stress. The effect of chilling-sensitive cultivars was more than that of chilling-tolerant cultivars, more phosphorus fertilizer properly improved seedling quality of rice, slowed relative chlorophyll content dropping degree of rice seeding, increased photosynthesis rate, Fv/Fm, qP and index of unsaturated fatty acids, and enhanced the ability to chilling-tolerant cultivars under low temperature. The effect on chilling-tolerant cultivars was significantly higher than that on chilling sensitive cultivars by applying more phosphorus fertilizer. Phosphate regulated photosynthetic physiology and membrane fluidity to reduce injury by low temperature, and increasd the cold tolerance capacity of rice.展开更多
基金the Administration of Central Funds Guiding the Local Science and Technology Development,China(202002069JC)the earmarked fund for the China Agriculture Research System(CARS-01-10)。
文摘Chalkiness is one of the most important agronomic traits in rice breeding,which directly affects the quality of rice seed.In this study,we identified a chalkiness endosperm mutant,chalk-h,from N-methyl-N-nitrosourea(MNU)-induced japonica rice cultivar Hwacheong(HC).Compared with wild type(WT)-HC,chalk-h showed severe chalkiness in the endosperm,yellowish green leaves,as well as reduced plant height.Scanning electron microscopy(SEM)analysis showed that starch grains in the chalk-h mutant were irregular in size and loosely arranged,with large gaps between granules,forming ovoid or orbicular shapes.MutMap analysis revealed that the phenotype of chalk-h is controlled by a single recessive gene LOC_Os11g39670 encoding seryl-tRNA synthetase,which is renamed as CHALK-H.A point mutation occurs in chalk-h on the sixth exon(at nucleotide 791)of CHALK-H,in which adenine(A)is replaced by thymidine(T),resulting in an amino acid codon change from glutamine(Glu)to valine(Val).The chalk-h mutant exhibited a heat-sensitive phenotype from the 3-leaf stage,including yellow-green leaves and reduced pigment content.The transcriptional expression of starch synthesis-related genes was down-regulated in the chalk-h mutants compared to WT-HC at different grain-filling stages.With an increase in temperature,the expression of photosynthesis-related genes was down-regulated in the chalk-h mutant compared to WT-HC.Overexpression of CHALK-H rescued the phenotype of chalk-h,with endosperm and leaf color similar to those of WT-HC.Our findings reveal that CHALK-H is a causative gene controlling chalkiness and leaf color of the chalk-h mutant.CHALK-H is the same gene locus as TSCD11,which was reported to be involved in chloroplast development under high temperature.We suggest that CHALK-H/TSCD11 plays important roles not only in chloroplast development,but also in photosynthesis and starch synthesis during rice growth and development,so it has great application potential in rice breeding for high quality and yield.
文摘目的建立了一种实时直接分析离子源(direct analysis in real time, DART)结合四极杆/静电轨道离子阱高分辨质谱法(Q-Exactive Orbitrap)快速筛查南美白对虾中磺胺类药物的方法。方法样品经过提取净化后,在离子化温度450℃,栅极电压350 V,样品传输速度0.2 mm/s的DART离子源正离子模式条件下进样,Orbitrap高分辨质谱在-全扫描/数据依赖二级扫描模式下进行定性检测。结果该方法检出限为0.5~2.7μg/kg,满足筛查要求。结论该方法分析速度快,定性准确,无需色谱分离过程,环境友好。
文摘目的建立一种实时直接分析(direct analysis in real time,DART)离子源结合四极杆/静电轨道离子阱高分辨质谱法(quadrupole/orbitrap high resolution mass spectrometry,Q-Orbitrap HRMS)快速筛查凉茶中非法添加的21种解热镇痛类药物。方法样品经50%甲醇水超声提取,过0.22μm微孔滤膜后,用DART-Q-Orbitrap HRMS测定。DART离子源的样品传输速度为0.2 mm/s、离子化温度为400℃、栅极电压为300 V,扫描模式为正离子模式。结果在全扫描模式下测定目标化合物的一级精密质量数,与理论精密质量数相比,相对误差小于1.65×10^(-6),可实现精准定性;同时建立的21种解热镇痛类药物的二级质谱信息库进一步提高定性分析的准确性。方法筛查限范围为1.00~270.00μg/kg,满足筛查要求。结论该方法具有分析速度快、精准定性、无需冗长色谱分离过程、环境友好等优势,可作为凉茶中21种解热镇痛类非法添加化学药物的高通量筛查和精准定性检测方法。
基金Supported by the Special Agricultural Project of Agricultural Department (200903003)the Agricultural Modernization Project in the Science and Technology Development Plan of Jilin Province (2009-2010) the High-yield Project of Science and Technology Department (2011BAD16B10)
文摘The study was designated to explore the physiological mechanism of cold tolerance enhanced by phosphate in rice. An experiment was conducted to investigate the effects of different levels of phosphate fertilizer on cold tolerance and its related physiological parameters in rice seedings （chilling-sensitive cv. Changbai 9 and chilling-tolerant cv. Jijing 81） under low temperature stress. At the same time, the identification of cold tolerance was conducted. Compared with the normal temperature treatment, the relative chlorophyll content, photosynthesis rate, Fv/Fm and qP decreased and index of unsaturated fatty acid increased in rice under low temperature stress. The effect of chilling-sensitive cultivars was more than that of chilling-tolerant cultivars, more phosphorus fertilizer properly improved seedling quality of rice, slowed relative chlorophyll content dropping degree of rice seeding, increased photosynthesis rate, Fv/Fm, qP and index of unsaturated fatty acids, and enhanced the ability to chilling-tolerant cultivars under low temperature. The effect on chilling-tolerant cultivars was significantly higher than that on chilling sensitive cultivars by applying more phosphorus fertilizer. Phosphate regulated photosynthetic physiology and membrane fluidity to reduce injury by low temperature, and increasd the cold tolerance capacity of rice.
