作者机构：
[Xilai Huang; Yinghui Xiao; Sujun Pan; Wei Yao; Wenfeng Chen; Bing Li; Xiaowen Ding; Jianfeng Liu; Jinjun Lin; Hao Huang; Xiaolong Zhou; Qianru Chen] Hunan Provincial Key Laboratory of Crop Gene Engineering, College of Agronomy, Hunan Agricultural University, Changsha, 410128, China;[Xionglun Liu] Hunan Provincial Key Laboratory of Crop Gene Engineering, College of Agronomy, Hunan Agricultural University, Changsha, 410128, China. xionglun@hunau.edu.cn;[Jinling Liu] Hunan Provincial Key Laboratory of Crop Gene Engineering, College of Agronomy, Hunan Agricultural University, Changsha, 410128, China. liujinling@hunau.edu.cn
通讯机构：
[Liu, Xionglun; Liu, Jinling] H;Hunan Provincial Key Laboratory of Crop Gene Engineering, College of Agronomy, Hunan Agricultural University, Changsha, 410128, China.
关键词：
Gibberellin signaling;NADP-malic enzyme;OsNADP-ME2;Plant height;Rice (Oryza sativa L.)
摘要：
Plants NADP-malic enzymes (NADP-MEs) act as a class of oxidative decarboxylase to mediate malic acid metabolism in organisms. Despite NADP-MEs have been demonstrated to play pivotal roles in regulating diverse biological processes, the role of NADP-MEs involving in plant growth and development remains rarely known. Here, we characterized the function of rice cytosolic OsNADP-ME2 in regulating plant height. The results showed that RNAi silencing and knock-out of OsNADP-ME2 in rice results in a dwarf plant structure, associating with significant expression inhibition of genes involving in phytohormone Gibberellin (GA) biosynthesis and signaling transduction, but with up-regulation for the expression of GA signaling suppressor SLR1. The accumulation of major bioactive GA(1), GA(4) and GA(7) are evidently altered in RNAi lines, and exogenous GA treatment compromises the dwarf phenotype of OsNADP-ME2 RNAi lines. RNAi silencing of OsNADP-ME2 also causes the reduction of NADP-ME activity associating with decreased production of pyruvate. Thus, our data revealed a novel function of plant NADP-MEs in modulation of rice plant height through regulating bioactive GAs accumulation and GA signaling, and provided a valuable gene resource for rice plant architecture improvement.
摘要：
OsNRAMP5 is a pivotal gene involved in the uptake and transport of cadmium and manganese in rice plants. While the knockout of OsNRAMP5 has significantly decreased cadmium accumulation in rice grains, its impact on the adaptability of indica hybrid rice and its paternal parent still needs to be more adequately explored. This study conducted a three-year field experiment with two of the OsNRAMP5 knockout lines (indica hybrid rice LYDG-1 and its paternal parent DG-1) and their wild-type at four distinct locations in the middle reaches of the Yangtze River. Their adaptability was evaluated by cadmium and manganese accumulation, yield traits, and grain quality. The findings reveal that OsNRAMP5 knockout lines, when grown in mildly and moderately Cd-contaminated paddies, exhibit significantly and stably lower cadmium and manganese accumulation compared with the wild-type. However, there were no significant differences in cadmium and manganese content between LYDG-1 and DG-1. Regarding yield traits, OsNRAMP5 knockout lines did not show a significant reduction compared with the wild-type, except for DG-1 in soil with lower manganese content. For grain quality, the quality of the appearance of OsNRAMP5 knockout lines significantly improved compared with the wild-type. However, the milling quality of DG-1 significantly reduced compared with the wild-type, while this negative impact for LYDG-1 was only observed in soils with lower manganese content. Overall, the indica hybrid rice with an OsNRAMP5 knockout exhibits better adaptability than its paternal parent in the middle reaches of the Yangtze River. These findings offer valuable insights into the potential application and promotion of OsNRAMP5 mutant rice varieties in the middle reaches of the Yangtze River.
作者机构：
[Xiao, Yinghui; Peng, Pei; Luo, Lihua; Jiang, Haoyu] Hunan Agr Univ, Coll Agron, Changsha 410128, Peoples R China.;[Ye, Changrong] Huazhi Biotech Co Ltd, Changsha 410125, Peoples R China.
通讯机构：
[Yinghui Xiao] C;College of Agronomy, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Author to whom correspondence should be addressed.
关键词：
hybrid rice;blast resistance;marker-assisted selection;thermo-sensitive genic male sterile line;gene pyramiding
摘要：
Rice blast caused by pathogenic fungus Magnaporthe oryzae is one of the most serious diseases in rice. The pyramiding of effective resistance genes into rice varieties is a potential approach to reduce the damage of blast disease. In this study, combinations of three resistance genes, Pigm, Pi48 and Pi49, were introduced into a thermo-sensitive genic male sterile (PTGMS) line Chuang5S through marker-assisted selection. The results showed that the blast resistance of improved lines increased significantly compared with Chuang5S, and the three gene pyramiding lines (Pigm + Pi48 + Pi49) had higher rice blast resistance level than monogenic line and digenic lines (Pigm +Pi48, Pigm + Pi49). The genetic backgrounds of the improved lines were highly similar (>90%) to the recurrent parent Chuang5S by using the RICE10K SNP chip. In addition, agronomic traits evaluation also showed pyramiding lines with two or three genes similar to Chuang5S. The yields of the hybrids developed from improved PTGMS lines and Chuang5S are not significantly different. The newly developed PTGMS lines can be practically used for the breeding of parental lines and hybrid varieties with broad spectrum blast resistance.
摘要：
The receptor protein PEX5, an important component of peroxisomes, regulates growth, development, and immunity in yeast and mammals. PEX5 also influences growth and development in plants, but whether it participates in plant immunity has remained unclear. Here, we report that knockdown of OsPEX5 enhances resistance to the rice blast fungus Magnaporthe oryzae. We demonstrate that OsPEX5 interacts with the E3 ubiquitin ligase APIP6, a positive regulator of plant immunity. APIP6 ubiquitinates OsPEX5 invitro and promotes its degradation invivo via the 26S proteasome pathway. In addition, OsPEX5 interacts with the aldehyde dehydrogenase OsALDH2B1, which functions in growth-defense trade-offs in rice. OsPEX5 stabilizes OsALDH2B1 to enhance its repression of the defense-related gene OsAOS2. Our study thus uncovers a previously unrecognized hierarchical regulatory mechanism in which an E3 ubiquitin ligase targets a peroxisome receptor protein that negatively regulates immunity in rice by stabilizing an aldehyde dehydrogenase that suppresses defense gene expression.
作者：
Liu Hong-mei;Shen Tao;Zhang Wen-yi;Shi Xi-wen;Dai Tao;...
期刊：
光谱学与光谱分析,2021年41(8):2432-2436 ISSN：1000-0593
通讯作者：
Xiao, Ying-Hui(xiaoyh@hunau.edu.cn)
作者机构：
[Shen Tao; Zhang Wen-yi; Bai Tao; Shi Xi-wen; Liu Hong-mei; Dai Tao; Xiao Ying-hui] Hunan Agr Univ, Coll Agron, Changsha 410128, Peoples R China.
通讯机构：
[Xiao, Y.-H.] C;College of Agronomy, China
关键词：
籼稻米;胶稠度;近红外模型;偏最小二乘法
摘要：
培育优质高产水稻品种是当前水稻育种的重要任务之一; 胶稠度是稻米蒸煮食味品质最重要的指标之一。 传统的化学法测定稻米胶稠度, 前处理复杂、 过程繁琐、 试剂消耗多, 难以满足大批量水稻品种(组合)胶稠度快速无损检测的需求。 近红外光谱分析能快速、 无损、 无污染地分析检测。 以137份南方稻区主栽或新育成的籼稻品种(组合)为供试材料, 用传统化学法测定其稻米胶稠度并收集其近红外光谱, 以建立南方籼稻米胶稠度近红外光谱分析模型, 并对模型进行校正、 检验。 用偏最小二乘法(PLS)分别经20种数学预处理和6种波长段(或组合)建立各自的近红外分析模型。 通过比较模型评价指标确定了平滑预处理为最佳预处理方式, 波长段1 100~1 650 nm为最优建模波长段。 平滑处理模型评价指标: 校准相关系数(R)、 检验相关系数(r)、 相对百分比偏差(RPD)分别为0.970 0, 0.964 2和3.780 5; 波长段1 100~1 650 nm模型评价指标: R, r和RPD分别为0.969 4, 0.963 8和3.758 6; 经平滑处理后在1 100~1 650 nm波长段建立了稻米胶稠度最优近红外分析模型, 其模型评价指标: R, r和RPD分别为0.979 0, 0.974 1和4.419 4; 再用30份验证集样本对所得的最优模型进行外部验证, 结果表明: 近红外检测值和化学值绝对误差在0.198 6~6.502 4 mm, 对其进行配对T检验, p=0.726>0.05, 表明该近红外模型的检测值与化学值无显著差异, 即应用此近红外模型快速无损检测稻米胶稠度是可行的。 本研究结果为优质水稻品种(组合)早世代材料的快速筛选及稻米胶稠度的批量快速分析检测提供了技术支持。 Cultivating high-quality and high-yielding rice varieties is one of the important tasks of current rice breeding, and gel consistency is one of the most important indicators of rice cooking and eating quality. The traditional chemical method for measuring the gel consistency of rice has complicated pretreatment, complicated process, and high reagent consumption. It is difficult to meet the needs of rapid non-destructive testing of the gel consistency for large batches of rice varieties (combinations). The near-infrared spectroscopy analysis technology can quickly, non-destructively, and non-pollutingly analyze. In this study, 137 indica rice varieties (combinations) mainly cultivated or newly bred in southern rice areas were used as the test materials, and their near-infrared spectra were measured by traditional chemical methods to collect their near-infrared spectra to establish near-infrared spectra of southern indica rice. Build an analysis model, and then correct and verify the model. The results showed that the partial least squares method (PLS) was used to establish their respective near infrared analysis models after 20 kinds of mathematical preprocessing and 6 kinds of wavelength bands (or combinations). By comparing the model evaluation indexes, it was determined that smooth pretreatment was the best pretreatment method, and the wavelength band of 1 100 to 1 650 nm was the best modeling wavelength band. Evaluation index of smoothing model: calibration correlation coefficient (R), test correlation coefficient (r), relative analysis error (RPD) were 0.970 0, 0.964 2, and 3.780 5 respectively; wavelength evaluation range: 1 100 to 1 650 nm Model evaluation indicators: R, r, RPD They were 0.969 4, 0.963 8, and 3.758 6 respectively; after smoothing, the best near-infrared analysis model of rice gel consistency was established in the wavelength range of 1 100 to 1 650 nm, and the model evaluation indicators: R, r, and RPD were 0.979 0, 0.974 1, and 4.419 4 respectively; Then used 30 samples to verify the obtained optimal model. It indicated that the absolute error between the near infrared predicted value and the chemical value was 0.198 6~6.502 4 mm, and paired t test showed that p=0.726>0.05, indicating no significant difference between the predicted value and the chemical value. The near-infrared model was feasible for rapid non-destructive testing of rice gel consistency. This study provides technical support for the rapid screening of high-quality rice varieties (combinations) in the early generation of materials and the rapid batch analysis of the gel consistency of rice.
关键词：
Rice;Cold tolerance;Bud burst stage;Genome-wide association study
摘要：
<jats:title>Abstract</jats:title><jats:p>Cold tolerance at the bud burst stage (CTB) is a key trait for direct-seeded rice. Although quantitative trait loci (QTL) affecting CTB in rice have been mapped using traditional linkage mapping and genome-wide association study (GWAS) methods, the underlying genes remain unknown. In this study, we evaluated the CTB phenotype of 339 cultivars in the Rice Diversity Panel II (RDP II) collection. GWAS identified four QTLs associated with CTB (<jats:italic>qCTBs</jats:italic>), distributed on chromosomes 1–3. Among them, <jats:italic>qCTB-1-1</jats:italic> overlaps with <jats:italic>Osa-miR319b</jats:italic>, a known cold tolerance micro RNA gene. The other three <jats:italic>qCTBs</jats:italic> have not been reported. In addition, we characterised the candidate gene <jats:italic>OsRab11C1</jats:italic> for <jats:italic>qCTB-1-2</jats:italic> that encodes a Rab protein belonging to the small GTP-binding protein family. Overexpression of <jats:italic>OsRab11C1</jats:italic> significantly reduced CTB, while gene knockout elevated CTB as well as cold tolerance at the seedling stage, suggesting that <jats:italic>OsRab11C1</jats:italic> negatively regulates rice cold tolerance. Molecular analysis revealed that <jats:italic>OsRab11C1</jats:italic> modulates cold tolerance by suppressing the abscisic acid signalling pathway and proline biosynthesis. Using RDP II and GWAS, we identified four <jats:italic>qCTBs</jats:italic> that are involved in CTB and determined the function of the candidate gene <jats:italic>OsRab11C1</jats:italic> in cold tolerance. Our results demonstrate that OsRab11C1 is a negative regulator of cold tolerance and knocking out of the gene by genome-editing may provide enhanced cold tolerance in rice.</jats:p>
摘要：
水稻叶穗色泽突变体为解析不同器官叶绿素生物合成之间的内在联系提供了优良的遗传材料.本研究鉴定了1份白叶白穗突变体wlwp7(white leaf and white panicle 7),分析了wlwp7的形态、生理和遗传特点.结果表明:wlwp7对低温敏感,当环境温度为20℃时苗期叶片白化,但温度升高至30℃后叶色正常;大田环境下wlwp7抽穗后颖壳白化,叶绿素含量降低至野生型的40.73％;除结实率较野生型T98B下降6.28％外,其他产量性状不受影响;遗传分析发现,wlwp7与T98B的正反杂交F2群体中都未出现白叶绿穗和绿叶白穗重组单株,经卡方检测白叶白穗突变单株与绿叶绿穗野生型单株的理论分离比符合1 ∶ 3,表明白叶白穗性状受同一隐性核基因控制;利用BSA策略进一步将wlwvp7定位在第3染色体上一个280 kb的区域内,该区域未有已报道的白叶白穗基因.本研究发现了wlwp7同时控制叶部和穗部叶绿素合成,精细定位结果为最终克隆wlwp7奠定了基础.
作者机构：
[郝明; 黄湘桂; 降好宇; Zeng G.; 肖应辉] Agronomy College, Hunan Agricultural University, Hunan Provincial Key Laboratory of Rice and Rapeseed Breeding for Disease Resistance, Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Changsha, 410128, China
