Genetic basis of kernel nutritional traits during maize domestication and improvement

The nutritional traits of maize kernels are important for human and animal nutrition, and these traits have undergone selection to meet the diverse nutritional needs of humans. However, our knowledge of the genetic basis of selecting for kernel nutritional traits is limited. Here, we identified both single and epistatic quantitative trait loci (QTLs) that contributed to the differences of oil and carotenoid traits between maize and teosinte. Over half of teosinte alleles of single QTLs increased the values of the detected oil and carotenoid traits. Based on the pleiotropism or linkage information of the identified single QTLs, we constructed a trait–locus network to help clarify the genetic basis of correlations among oil and carotenoid traits. Furthermore, the selection features and evolutionary trajectories of the genes or loci underlying variations in oil and carotenoid traits revealed that these nutritional traits produced diverse selection events during maize domestication and improvement. To illustrate more, a mutator distance–relative transposable element (TE) in intron 1 of DXS2, which encoded a rate‐limiting enzyme in the methylerythritol phosphate pathway, was identified to increase carotenoid biosynthesis by enhancing DXS2 expression. This TE occurs in the grass teosinte, and has been found to have undergone selection during maize domestication and improvement, and is almost fixed in yellow maize. Our findings not only provide important insights into evolutionary changes in nutritional traits, but also highlight the feasibility of reintroducing back into commercial agricultural germplasm those nutritionally important genes hidden in wild relatives.     

未来气候变化情景下河南省粮食安全气候承载力评估

为探究未来气候变化对河南省粮食生产的影响,基于夏玉米和冬小麦两种主粮作物的生产潜力和气候资源承载力,结合1961—2017年河南省111个气象站的观测数据以及区域气候模式输出的2041—2080年RCP4.5和RCP8.5两种排放情景下的气象资料,采用农业生态区域法(AEZ模型)计算了河南省气候生产潜力及其变化特征,并根据不同生活水平下的粮食需求指标,分析了河南省的气候承载力和剩余空间。结果表明: 1961—2017年,河南省夏玉米气候生产潜力平均为18408.87 kg·hm^-2,表现为中东部高、西部低;与基准时段(1981—2010年)相比,RCP4.5和RCP8.5情景下分别下降13.0%和8.0%,高值中心由豫东地区向豫西南地区转移。1961—2017年,冬小麦气候生产潜力平均值为10889.79 kg·hm^-2,呈中部高、北部低;与基准时段相比,RCP4.5和RCP8.5情景下分别减少18.6%、21.7%。当前,在温饱水平和小康水平粮食需求条件下,最大气候资源承载力分别平均养活人口2.52亿和1.83亿。2070s(2071—2080年)最大气候资源承载力平均养活人口有所减少,与基准时段相比,RCP4.5情景下小康水平和温饱水平分别下降9.7%和18.4%,RCP8.5情景下小康水平和温饱水平分别下降7.7%和16.6%。当前气候条件下,河南省气候资源相对剩余率在-93.0%～356.9%,与基准时段相比,未来气候资源相对剩余率减少近40%。     

不同缓释过氧化钙对潜育环境下水稻土微生物特性的影响

为了解不同缓释过氧化钙对潜育化稻田土壤微生物特性的影响,于网室内进行潜育化稻田环境模拟试验,以不施过氧化钙为对照,探究过氧化钙粉末、过氧化钙颗粒与4种不同释氧效果的包膜过氧化钙在早稻分蘖期同等时期对潜育化稻田土壤活性有机碳、有效养分及微生物特性的影响。结果表明: 施用过氧化钙均能提高土壤活性有机碳、有效养分、微生物生物量及可培养微生物数量和酶活性,包膜过氧化钙对土壤微生物和酶活性的改善效果较好,其次依次为过氧化钙颗粒和过氧化钙粉末。包膜过氧化钙处理中,以乙基纤维素包膜效果最好,与不施过氧化钙处理相比,其土壤活性有机碳、微生物生物量碳、微生物生物量氮、微生物生物量磷分别显著提高19.4%、11.4%、121.5%、127.2%,土壤碱解氮和有效磷分别提高4.0%和45.5%;土壤可培养细菌和可培养微生物总量分别显著提高137.3%和113.7%,真菌和放线菌数量分别提高33.6%和44.7%;蔗糖酶、磷酸酶和脲酶活性分别显著提高92.4%、91.8%和112.5%,过氧化氢酶活性提高17.1%。研究结果可为包膜过氧化钙对潜育化稻田改良提供参考。     

LncRNA AWPPH as a prognostic predictor in human cancers in Chinese population: evidence from meta-analysis

Background: Long non-coding RNA associated with poor prognosis of hepatocellular carcinoma (AWPPH) is dysregulated in a variety of human cancers. However, the prognostic value of AWPPH in various cancers remains unclear.Methods: Comprehensive literature search was performed in PubMed, Web of Science, CNKI and Wangfang databases, and eligible studies were obtained according to the inclusion and exclusion criteria. The pooled hazard ratios (HRs) and odds ratios (ORs) were applied to assess the clinical value of AWPPH expression for overall survival (OS) and clinicopathological features.Results: A total of 19 articles including 1699 cancer patients were included in the study. The pooled results demonstrated that evaluated AWPPH expression was positively related to a poorer overall survival of patients with cancers (HR = 1.79, 95%CI: 1.44–2.14, P<0.001). Subgroup analysis revealed that tumor type and sample size affect the predictive value of AWPPH on OS, whereas cut-off value and HR estimation method have no impact on it. In addition, the pooled data also showed that AWPPH was positively linked to advanced TNM stage (OR = 2.50, 95%CI: 1.94–3.22, P<0.001), bigger tumor size (OR = 2.64, 95%CI: 1.47–4.73, P=0.001), macro-vascular invasion (OR = 2.08, 95%CI: 1.04–4.16, P=0.04) and lymph node metastasis (OR = 2.68, 95%CI: 1.82–3.96, P<0.001). Moreover, the results of the trim and fill analysis confirmed the reliability of our finding.Conclusions: Up-regulation of AWPPH was associated with advanced TNM stage, bigger tumor size, worse lymph node metastasis, macro-vascular invasion and shorter overall survival, suggesting that AWPPH may serve as a biomarker for prognosis and clinicopathological characteristics in human cancers among the Chinese population.