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植物数量性状关联分析研究进展 被引量:114
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作者 杨小红 严建兵 +2 位作者 郑艳萍 余建明 李建生 《作物学报》 CAS CSCD 北大核心 2007年第4期523-530,共8页
关联分析是新近开始在植物数量性状研究和植物育种中应用的一种分析方法。它以连锁不平衡为基础鉴定某一群体内性状与遗传标记或候选基因间的关系。本文在介绍连锁不平衡的定义和度量方法的基础上,综述了连锁不平衡和关联分析在植物方... 关联分析是新近开始在植物数量性状研究和植物育种中应用的一种分析方法。它以连锁不平衡为基础鉴定某一群体内性状与遗传标记或候选基因间的关系。本文在介绍连锁不平衡的定义和度量方法的基础上,综述了连锁不平衡和关联分析在植物方面的研究进展,并讨论了交配体系、重组、遗传漂变等对连锁不平衡程度的影响,以及连锁不平衡程度和群体结构对关联分析的影响,最后讨论了关联分析在植物数量性状和分子育种研究中可能的应用。 展开更多
关键词 关联分析 连锁不平衡 数量性状
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阿拉善高原中全新世干旱事件的湖泊记录研究 被引量:73
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作者 陈发虎 吴薇 +4 位作者 朱艳 J.A.Holmes D.B.Madsen 金明 C.G.Oviatt 《科学通报》 EI CAS CSCD 北大核心 2004年第1期1-9,共9页
中国国内普遍流行的观点认为,中国中全新世是一个夏季风盛行的温暖湿润时期,称作全新世“最宜期”或“大暖期”.内蒙古西部阿拉善高原的湖泊沉积和湖泊地貌则显示了一种相反的状况,这一区域中全新世气候干旱,黑河的终闾湖泊居延泽、石... 中国国内普遍流行的观点认为,中国中全新世是一个夏季风盛行的温暖湿润时期,称作全新世“最宜期”或“大暖期”.内蒙古西部阿拉善高原的湖泊沉积和湖泊地貌则显示了一种相反的状况,这一区域中全新世气候干旱,黑河的终闾湖泊居延泽、石羊河的终闾湖泊潴野泽和腾格里沙漠东缘的头道湖均经历了湖泊缩小或干涸过程,时代为距今7000-5000日历年.潴野泽高分辨率(50年)的孢粉记录显示,季风边缘区的石羊河流域,特别是祁连山地的植被发生显著衰退,降水减少.中全新世的干旱事件存在于现代夏季风边缘区的较大范围,包括阿拉善高原、鄂尔多斯高原、内蒙古高原中东部,甚至黄土高原南部,指示了东亚夏季风在全新世期间的一次大衰退.中全新世东亚夏季风衰退期间气候寒冷,这在青藏高原及其周边山地尤为明显. 展开更多
关键词 阿拉善高原 中全新世 干旱事件 湖泊记录 中国 气候变化
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晚第四纪“吉兰泰-河套”古大湖的初步研究 被引量:67
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作者 陈发虎 范育新 +5 位作者 春喜 D.B.Madsen C.G.Oviatt 赵晖 杨丽萍 孙洋 《科学通报》 EI CAS CSCD 北大核心 2008年第10期1207-1219,共13页
通过野外考察、探坑剖面观测和遥感影像分析,发现吉兰泰盐湖周围存在高湖面遗留的地貌、沉积和生物证据.在海拔1060,1050,1044和1035m共有4道古湖岸堤,分别高出现代盐湖37,27,21和12m.在海拔1070-1080m之间(高出现代盐湖47-57m)存在... 通过野外考察、探坑剖面观测和遥感影像分析,发现吉兰泰盐湖周围存在高湖面遗留的地貌、沉积和生物证据.在海拔1060,1050,1044和1035m共有4道古湖岸堤,分别高出现代盐湖37,27,21和12m.在海拔1070-1080m之间(高出现代盐湖47-57m)存在古湖滨砂砾石沉积,若干地点保存有古湖岸堤形态;在乌兰布和沙漠腹地的贺日木西尼也发现1080m高程及其以下的湖滨砂砾石和典型湖相沉积,以及从海拔1050-1035m,长11km的典型砂嘴.河套黄河南岸黄河水文站砂场、什拉召砂场也发现古湖岸堤,杭锦旗巴拉贡砂场发现发育在冲洪积砂砾石层上的湖滨砾石沉积.沿狼山-阴山南麓若干剖面点发现湖岸侵蚀台地及湖滩岩和湖滨相沉积.在黄河进入河套的乌海附近发现水下三角洲沉积,黄河出口的托克托台地存在典型湖相沉积.在湖滨沉积物中,普遍保存有蓝蚬、萝卜螺和扁卷螺等水生软体动物壳体,部分湖相细粒沉积物中也可见到介形虫壳体.出露较好的湖相沉积剖面具有典型的进积型垂向层序,较高湖岸堤普遍保存有湖滩岩.这些证据说明,曾存在一个覆盖吉兰泰和河套平原大部分地区的巨大古湖,湖面海拔可达1080m,建议称作“吉兰泰-河套”古大湖.光释光测年结果表明,该古大湖存在于距今5-6万年前.海拔1060-1035m间的4道湖岸堤代表了5-6万年到全新世早期间的湖面波动,而真正吉兰泰盐湖状态仅形成于距今5500年以来.“吉兰泰-河套”古大湖的发现,对进一步深入研究河套地区晚第四纪黄河发育、乌兰布和-库布齐沙漠的形成演化以及区域气候变化和新构造运动都具有重要意义. 展开更多
关键词 “吉兰泰-河套”古湖 湖岸堤 湖相沉积 晚第四纪 高湖面
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基于等级层次分析法的金沙江下游地区生态功能分区 被引量:51
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作者 高俊刚 吴雪 +3 位作者 张镱锂 刘林山 王兆锋 姚治君 《生态学报》 CAS CSCD 北大核心 2016年第1期134-147,共14页
金沙江下游地区是我国西南重要的生态环境保护区域,也是我国未来水电建设的重要区域,在西南民族经济和区域可持续发展等方面都具有十分重要的战略意义。该地区水能资源开发潜力巨大,是我国重要的能源基地,但是该地区生态环境相对脆弱。... 金沙江下游地区是我国西南重要的生态环境保护区域,也是我国未来水电建设的重要区域,在西南民族经济和区域可持续发展等方面都具有十分重要的战略意义。该地区水能资源开发潜力巨大,是我国重要的能源基地,但是该地区生态环境相对脆弱。为了保护这些脆弱生态环境的地区,尽管国家和大多数省级层次的生态功能分区已经制定并颁布和实施,但是如何探索和制定区域、流域尺度的生态功能分区研究却为数不多。而大尺度的生态功能分区研究并不一定非常适合这一具体流域实际情况,所以小尺度典型流域的生态功能分区探索是非常必要的。基于金沙江下游地区的生态环境特征,运用空间分析的方法和技术,采用定性和定量分析相结合的等级层次分析法,对金沙江下游地区进行了生态功能分区。结果表明:金沙江下游地区可划分为2个生态区、6个生态亚区和29个生态功能区;以流域尺度上水源涵养、水土保持和生物多样性保护为主导生态系统功能,进行了重要生态功能分区,确定了金沙江下游地区具有重要意义的19个重要生态功能区域。该重点区域的划分对金沙江下游地区生态安全具有重要生态意义,可用于指导金沙江下游地区自然资源的有序开发利用和产业布局的合理配置,为金沙江下游地区生态环境保护提供科学依据,对维护金沙江下游地区的水电生态安全提供重要指导。 展开更多
关键词 金沙江下游 生态适宜性 生态敏感性 生态系统服务 生态功能分区
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利用Fhb1基因功能标记选择提高黄淮冬麦区小麦品种对赤霉病的抗性 被引量:44
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作者 张宏军 宿振起 +10 位作者 柏贵华 张旭 马鸿翔 李腾 邓云 买春艳 于立强 刘宏伟 杨丽 李洪杰 周阳 《作物学报》 CAS CSCD 北大核心 2018年第4期505-511,共7页
赤霉病已上升为黄淮冬麦区的主要病害,提高小麦品种对赤霉病的抗性成为该麦区主要的育种目标之一。宁麦9号、生选6号、建阳798、建阳84、苏麦3号和宁麦13均携带Fhb1基因,对赤霉病表现中抗水平以上。本研究以这6个品种(系)为供体,分别与... 赤霉病已上升为黄淮冬麦区的主要病害,提高小麦品种对赤霉病的抗性成为该麦区主要的育种目标之一。宁麦9号、生选6号、建阳798、建阳84、苏麦3号和宁麦13均携带Fhb1基因,对赤霉病表现中抗水平以上。本研究以这6个品种(系)为供体,分别与高感赤霉病的周麦16矮败小麦近等基因系杂交和回交,构建6个回交群体。利用Fhb1基因的KASP标记在回交后代中进行基因型分析,分别选择携带和不携带Fhb1基因的可育株,对后代株系进行单花滴注接种鉴定和田间病圃自然鉴定。回交后代携带Fhb1家系整体抗性达到中感,比不携带Fhb1家系的平均病小穗数低4.2(P<0.01),平均病情指数低4.0,比轮回亲本周麦16的平均病小穗数和病情指数分别低8.1(P<0.01)和28.4(P<0.01)。不同供体品种(系)回交后代在赤霉病抗性上表现出明显差异,以生选6号为供体的回交后代家系抗性表现最好。本研究表明,利用Fhb1基因分子标记辅助选择技术能够有效地提高黄淮冬麦区小麦品种的赤霉病抗性水平。 展开更多
关键词 小麦 赤霉病抗性 Fhb1基因 分子标记辅助选择
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Inducible direct plant defense against insect herbivores: A review 被引量:39
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作者 Ming-Shun Chen 《Insect Science》 SCIE CAS CSCD 2008年第2期101-114,共14页
Plants respond to insect herbivory with responses broadly known as direct defenses, indirect defenses, and tolerance. Direct defenses include all plant traits that affect susceptibility of host plants by themselves. O... Plants respond to insect herbivory with responses broadly known as direct defenses, indirect defenses, and tolerance. Direct defenses include all plant traits that affect susceptibility of host plants by themselves. Overall categories of direct plant defenses against insect herbivores include limiting food supply, reducing nutrient value, reducing preference, disrupting physical structures, and inhibiting chemical pathways of the attacking insect. Major known defense chemicals include plant secondary metabolites, protein inhibitors of insect digestive enzymes, proteases, lectins, amino acid deaminases and oxidases. Multiple factors with additive or even synergistic impact are usually involved in defense against a specific insect species, and factors of major importance to one insect species may only be of secondary importance or not effective at all against another insect species. Extensive qualitative and quantitative high throughput analyses of temporal and spatial variations in gene expression, protein level and activity, and metabolite concentration will accelerate not only the understanding of the overall mechanisms of direct defense, but also accelerate the identification of specific targets for enhancement of plant resistance for agriculture. 展开更多
关键词 chemical defense defensive protease LECTINS protease inhibitor secondary metabolite
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Biochar and its importance on nutrient dynamics in soil and plant 被引量:30
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作者 Md Zahangir Hossain Md Mezbaul Bahar +6 位作者 Binoy Sarkar Scott Wilfred Donne Young Sik Ok Kumuduni Niroshika Palansooriya Mary Beth Kirkham Saikat Chowdhury Nanthi Bolan 《Biochar》 2020年第4期379-420,共42页
Biochar,an environmentally friendly soil conditioner,is produced using several thermochemical processes.It has unique characteristics like high surface area,porosity,and surface charges.This paper reviews the fertiliz... Biochar,an environmentally friendly soil conditioner,is produced using several thermochemical processes.It has unique characteristics like high surface area,porosity,and surface charges.This paper reviews the fertilizer value of biochar,and its effects on soil properties,and nutrient use efficiency of crops.Biochar serves as an important source of plant nutrients,especially nitrogen in biochar produced from manures and wastes at low temperature(≤400℃).The phosphorus,potassium,and other nutrient contents are higher in manure/waste biochars than those in crop residues and woody biochars.The nutrient contents and pH of biochar are positively correlated with pyrolysis temperature,except for nitrogen content.Biochar improves the nutrient retention capacity of soil,which depends on porosity and surface charge of biochar.Biochar increases nitrogen retention in soil by reducing leaching and gaseous loss,and also increases phosphorus availability by decreasing the leaching process in soil.However,for potassium and other nutrients,biochar shows inconsistent(positive and negative)impacts on soil.After addition of biochar,porosity,aggregate stability,and amount of water held in soil increase and bulk density decreases.Mostly,biochar increases soil pH and,thus,influences nutrient availability for plants.Biochar also alters soil biological properties by increasing microbial populations,enzyme activity,soil respiration,and microbial biomass.Finally,nutrient use efficiency and nutrient uptake improve with the application of biochar to soil.Thus,biochar can be a potential nutrient reservoir for plants and a good amendment to improve soil properties. 展开更多
关键词 BIOCHAR NUTRIENTS MANURE Soil properties Nutrient use efficiency
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Two gap-free reference genomes and a global view of the centromere architecture in rice 被引量:30
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作者 Jia-Ming Song Wen-Zhao Xie +22 位作者 Shuo Wang Yi-Xiong Guo Dal-Hoe Koo Dave Kudrna Chenbo Gong Yicheng Huang Jia-Wu Feng Wenhui Zhang Yong Zhou Andrea Zuccolo Evan Long Seunghee Lee Jayson Talag Run Zhou Xi-Tong Zhu Daojun Yuan Joshua Udall Weibo Xie Rod AWing Qifa Zhang Jesse Poland Jianwei Zhang Ling-Ling Chen 《Molecular Plant》 SCIE CAS CSCD 2021年第10期1757-1767,共11页
Rice(Oryza sativa),a major staple throughout the world and a model system for plant genomics and breeding,was the first crop genome sequenced almost two decades ago.However,reference genomes for all higher organisms t... Rice(Oryza sativa),a major staple throughout the world and a model system for plant genomics and breeding,was the first crop genome sequenced almost two decades ago.However,reference genomes for all higher organisms to date contain gaps and missing sequences.Here,we report the assembly and analysis of gap-free reference genome sequences for two elite O.sativa xian/indica rice varieties,Zhenshan 97 and Minghui 63,which are being used as a model system for studying heterosis and yield.Gap-free reference genomes provide the opportunity for a global view of the structure and function of centromeres.We show that all rice centromeric regions share conserved centromere-specific satellite motifs with different copy numbers and structures.In addition,the similarity of CentO repeats in the same chromosome is higher than across chromosomes,supporting a model of local expansion and homogenization.Both genomes have over 395 non-TE genes located in centromere regions,of which∼41%are actively transcribed.Two large structural variants at the end of chromosome 11 affect the copy number of resistance genes between the two genomes.The availability of the two gap-free genomes lays a solid foundation for further understanding genome structure and function in plants and breeding climate-resilient varieties. 展开更多
关键词 rice genome ZS97 MH63 hybrid rice centromere architecture
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Preliminary research on Megalake Jilantai-Hetao in the arid areas of China during the Late Quaternary 被引量:27
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作者 CHEN FaHu FAN YuXin +5 位作者 CHUN Xi D.B. MADSEN C.G. OVIATT ZHAO Hui YANG LiPing SUN Yang 《Chinese Science Bulletin》 SCIE EI CAS 2008年第11期1725-1739,共15页
我们识别了 geomorphological,在通过地调查并且通过地区性的遥感的分析的当前的 Jilantai 盐湖附近的高湖层次的沉积、生物的证据想象。在约 1060, 1050, 1044 和 1035 m a.s.l 的举起有四组海岸线,是在当前的盐湖上面的 37, 27,... 我们识别了 geomorphological,在通过地调查并且通过地区性的遥感的分析的当前的 Jilantai 盐湖附近的高湖层次的沉积、生物的证据想象。在约 1060, 1050, 1044 和 1035 m a.s.l 的举起有四组海岸线,是在当前的盐湖上面的 37, 27, 21 和 12 m 分别地出现。沙和石子的沿岸的存款在在 1070 和 1080 m a.s.l 之间的举起被发现,比水流高的 47 ~ 57 m 腌湖表面,尽管 palaeoshoreline 地形仅仅在几个地点被保存。在 Herimuxini,在 Ulan Buh 荒芜的、典型湖的沉积和沙石子的北边缘上,沿岸的存款也发生在 1080 m a.s.l 并且在下面的举起。典型吐痰扩大的 A 11-km-long 从逐渐地在它的大拐弯上沿着黄河的南部的银行在一些沙石子石场从 1050 ~ 1035 m a.s.l 在举起减少的这条海岸线东方海岸线特征例如在水文学计量器车站和 Shilazhao 镇附近定位的那些,被识别。沿岸的存款 overlying 冲积的洪水的层在 Hangjin 在 Balagong 附近发生在沙石场县。也有沙滩岩石和沿岸的存款,沿着 Langshan-Yinshan 山的南部的山麓在几个地点在 cut-and-built 平台上保存。另外,揭示水下的三角洲沉积的侧面在 Wuhai 附近被识别,在黄河进入盆的地方。典型的湖沉积也在 Hetao 平原的东方结束在 Togtoh 站台存在。水的软体动物壳在沿岸的存款是普通的,包括 Corbicula 的几种,根值 lagotis, R。xauricularia 和 Gyraulus convexiusculus。Ostracode 壳能也在更好的沉积被识别。典型垂直 prograding 序列在湖的沉积很好被保存的露头是明显的。滚动波浪的卵石和沙滩岩石很通常在更高的举起在堤在侧面的顶上被保存。所有这些证据建议曾经有一个巨大的palaeo湖,用到达我们指的 &#8764;1080 m a.s.l 的最高的湖水平盖住 Jilantai 区域和 Hetao 平原的大多数部分巨大的 paleolake ,比现代的湖贝加尔湖大,作为“ Megalake Jilantai-Hetao ”. OSL 标� 展开更多
关键词 中国 晚第四纪 干旱地区 古气候学
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Indirect plant defense against insect herbivores: a review 被引量:22
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作者 Zainab Aljbory Ming-Shun Chen 《Insect Science》 SCIE CAS CSCD 2018年第1期2-23,共22页
Plants respond to herbivore attack by launching 2 types of defenses: direct defense and indirect defense. Direct defense includes all plant traits that increase the resistance of host plants to insect herbivores by a... Plants respond to herbivore attack by launching 2 types of defenses: direct defense and indirect defense. Direct defense includes all plant traits that increase the resistance of host plants to insect herbivores by affecting the physiology and/or be- havior of the attackers. Indirect defense includes all traits that by themselves do not have significant direct impact on the attacking herbivores, but can attract natural en- emies of the herbivores and thus reduce plant loss. When plants recognize herbivore- associated elicitors, they produce and release a blend of volatiles that can attract preda- tors, parasites, and other natural enemies. Known herbivore-associated elicitors include fatty acid-amino acid conjugates, sulfur-containing fatty acids, fragments of cell walls, peptides, esters, and enzymes. Identified plant volatiles include terpenes, nitrogenous compounds, and indoles. In addition, constitive traits including extrafloral nectars, food bodies, and domatia can be further induced to higher levels and attract natural enemies as well as provide food and shelter to carnivores. A better understanding of indirect plant defense at global and componential levels via advanced high throughput technolo- gies may lead to utilization of indirect defense in suppression of herbivore damage to plants. 展开更多
关键词 ELICITOR indirect plant defense natural enemies VOLATILE
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气候变化背景下东北三省春玉米产量潜力的时空特征 被引量:24
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作者 刘志娟 杨晓光 +2 位作者 吕硕 王静 LIN Xiao-mao 《应用生态学报》 CAS CSCD 北大核心 2018年第1期103-112,共10页
以东北三省春玉米种植区为研究区域,利用当地地面气象观测资料、农业气象观测站春玉米多年试验资料和县级春玉米实际产量资料,使用验证后的农业生产系统模拟模型(APSIM-Maize),分析研究区域春玉米1961—2015年不同水平产量潜力及实际产... 以东北三省春玉米种植区为研究区域,利用当地地面气象观测资料、农业气象观测站春玉米多年试验资料和县级春玉米实际产量资料,使用验证后的农业生产系统模拟模型(APSIM-Maize),分析研究区域春玉米1961—2015年不同水平产量潜力及实际产量的时空分布特征,并解析气候波动对产量潜力的影响.结果表明:1961—2015年,研究区域春玉米潜在产量平均值为12.2 t·hm^(-2),且呈现明显的经向和纬向空间分布,即由南向北递减、西部高于东部.研究区域春玉米可获得产量平均值为11.3 t·hm^(-2),与潜在产量呈相似的分布特征.在目前农户的栽培水平下,春玉米农户潜在产量和农户实际产量全区多年平均值分别为6.5和4.5t·hm^(-2).在品种和栽培管理措施不变的条件下,研究区潜在产量、可获得产量和农户潜在产量总体呈显著减少趋势,减幅分别为0.34、0.25和0.10 t·hm^(-2)·(10 a)^(-1).农户实际产量呈增加趋势,增幅为1.27 t·hm^(-2)·(10 a)^(-1).气候波动使东北三省春玉米潜在产量、可获得产量和农户潜在产量年际间波动范围分别为10.0~14.4、9.8~13.3和4.4~8.5 t·hm^(-2). 展开更多
关键词 东北三省 玉米 潜在产量 可获得产量 农户潜在产量 农户实际产量
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东北三省春玉米产量差时空分布特征 被引量:24
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作者 刘志娟 杨晓光 +2 位作者 吕硕 王静 LIN XiaoMao 《中国农业科学》 CAS CSCD 北大核心 2017年第9期1606-1616,共11页
【目的】随着人口增加、气候变化和环境问题日益凸显,粮食生产能力及粮食安全受到广泛重视。然而,目前中国粮食产量远远低于作物潜在产量,如何利用有限耕地生产更多粮食已经成为中国农业目前面临的重大问题。东北三省是中国重要的玉米... 【目的】随着人口增加、气候变化和环境问题日益凸显,粮食生产能力及粮食安全受到广泛重视。然而,目前中国粮食产量远远低于作物潜在产量,如何利用有限耕地生产更多粮食已经成为中国农业目前面临的重大问题。东北三省是中国重要的玉米生产区,其春玉米产量占全国总产量的29%,该区玉米产量提升对中国粮食安全具有重要的意义。【方法】论文以东北三省春玉米种植区为研究区域,基于1961—2010年气候资料、农业气象观测站作物资料和统计资料,利用农业生产系统模拟模型(APSIM-Maize)和数理统计方法,解析气候变化背景下研究区域春玉米潜在产量与实际产量的差及各级产量差的时空分布特征,为提升东北三省春玉米产量提供科学依据和参考。【结果】东北三省春玉米潜在产量与农户实际产量之间产量差(总产量差)呈明显的经向和纬向分布(P<0.01),即由南向北递减,由西向东递减,且地区间差异较大,变化范围为4.8—11.9 t·hm^(-2)。春玉米潜在产量与可获得产量之间的产量差(产量差1)、可获得产量与农户潜在产量之间的产量差(产量差2)均呈现随经度升高而降低的趋势,这与春玉米生长季内降水量分布有关。产量差1变化范围在0.06—3.2 t·hm^(-2)之间,产量差2地区间差异较大,变化范围为1.7—8.0 t·hm^(-2),主要是由于栽培管理措施的差异造成的。从全区50年平均来看,春玉米潜在产量与实际产量间的产量差为64%,其中由于不可转化的技术因素、农学因素和经济社会因素限制的产量差分别为8%、40%和16%。从时间变化趋势来看,过去50年(1961—2010)研究区域春玉米各级产量差均呈现减小的趋势,其中总产量差和产量差3呈显著缩小趋势(P<0.01),每10年分别缩小1.55 t·hm^(-2)和1.40 t·hm^(-2),但产量差1和产量差2变化趋势并不显著。【结论】东北三省春玉米潜在产量与农户实际� 展开更多
关键词 东北三省 玉米 产量差 时空特征
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一种快速高效的DNA提取方法研究 被引量:21
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作者 戴剑 洪德林 +1 位作者 张大栋 吴燕 《麦类作物学报》 CAS CSCD 北大核心 2011年第3期437-442,共6页
DNA提取技术是分子实验的一个重要步骤,快速、高效的植物DNA提取方法是样品需要量大的分子实验的一个关键技术。本实验通过改进传统的DNA提取方法,使用96孔联体试管板,而不是单个离心试管,对叶片进行冷冻干燥后粉碎,无需使用液氮。在实... DNA提取技术是分子实验的一个重要步骤,快速、高效的植物DNA提取方法是样品需要量大的分子实验的一个关键技术。本实验通过改进传统的DNA提取方法,使用96孔联体试管板,而不是单个离心试管,对叶片进行冷冻干燥后粉碎,无需使用液氮。在实验过程中,使用排枪操作,CTAB法提取DNA。以小麦为例,依据该方法提取幼苗叶片DNA,并选取6对引物对DNA样品进行PCR扩增,使用ABI PRISM3730 DNA分析仪对扩增产物进行分析,以检测提取的DNA质量。结果表明,本实验的DNA提取方法所得到的PCR扩增条带均有较高的强度。在6对实验引物的扩增结果中,扩增条带强度最好的引物有98%的样品在6935~16786 RFU(Relative Fluorescence Unit)之间;扩增条带强度较低的引物有93%的样品在532~1111 RFU之间;在所有的PCR扩增反应中,最低PCR扩增条带强度为205 RFU,缺带样品数量平均只有0.8%。按照本实验的方法操作,每人每天可提取上千个样品的DNA。因此,该DNA提取方法是一种高效、快速、能获得高质量DNA的有效方法。 展开更多
关键词 小麦 DNA 提取方法
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Soil Aggregate Stability and Aggregate-Associated Carbon Under Different Tillage Systems in the North China Plain 被引量:21
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作者 DU Zhang-liu REN Tu-sheng +2 位作者 HU Chun-sheng ZHANG Qing-zhong Humberto Blanco-Canqui 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第11期2114-2123,共10页
The inlfuences of tillage systems on soil carbon (C) stocks have been studied extensively, but the distribution of soil C within aggregate fractions is not well understood. The objective of this study was to determi... The inlfuences of tillage systems on soil carbon (C) stocks have been studied extensively, but the distribution of soil C within aggregate fractions is not well understood. The objective of this study was to determine the inlfuences of various tillage systems on soil aggregation and aggregate-associated C under wheat (Triticum aestivum L.) and corn (Zea mays L.) double cropping systems in the North China Plain. The experiment was established in 2001, including four treatments:moldboard plow (MP) with residue (MP+R) and without residue (MP-R), rotary tillage with residue (RT), and no-till with residue (NT). In 2007 soil samples were collected from the 0-5, 5-10, and 10-20 cm depths, and were separated into four aggregate-size classes (〉2 000, 250-2 000, 53-250, and〈53 μm) by wet-sieving method. Aggregate-associated C was determined, and the relationships between total soil C concentration and aggregation-size fractions were examined. The results showed that NT and RT treatments signiifcantly increased the proportion of macroaggregate fractions (〉2 000 and 250-2 000 μm) compared with the MP-R and MP+R treatments. Averaged across all depths, mean weight diameters of aggregates (MWD) in NT and RT were 47 and 20% higher than that in MP+R. The concentration of bulk soil organic C was positively correlated with MWD (r=0.98; P=0.024) and macroaggregate fraction (r=0.96; P=0.036) in the 0-5 cm depth. In the 0-20 cm depth, comparing with MP+R, total C occluded in the〉2 000 μm fraction was increased by 9 and 6%under NT and RT, respectively. We conclude that adoption of conservation tillage system, especially no-till, can increase soil macro-aggregation and total C accumulation in macroaggregates, which may improve soil C sequestration in the intensive agricultural region of the North China Plain. 展开更多
关键词 tillage systems aggregate stability aggregate-associated C
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Xa1 Allelic R Genes Activate Rice Blight Resistance Suppressed by Interfering TAL Effectors 被引量:19
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作者 Chonghui Ji Zhiyuan Ji +5 位作者 Bo Liu He Cheng Hua Liu Sanzhen Liu Bing Yang Gongyou Chen 《Plant Communications》 2020年第4期54-62,共9页
Xanthomonas oryzae pathovar oryzae(Xoo)uses transcription activator-like effectors(TALEs)to cause bacterial blight(BB)in rice.In turn,rice has evolved several mechanisms to resist BB by targeting TALEs.One mechanism i... Xanthomonas oryzae pathovar oryzae(Xoo)uses transcription activator-like effectors(TALEs)to cause bacterial blight(BB)in rice.In turn,rice has evolved several mechanisms to resist BB by targeting TALEs.One mechanism involves the nucleotide-binding leucine-rich repeat(NLR)resistance gene Xa1 and TALEs.Reciprocally,Xoo has evolved TALE variants,C-terminally truncated versions(interfering TALEs or iTALEs),to overcome Xa1 resistance.However,it remains unknown to what extent the two co-adaptive mechanisms mediate Xoo–rice interactions.In this study,we cloned and characterized five additional Xa1 allelic R genes,Xa2,Xa31(t),Xa14,CGS-Xo111,and Xa45(t)from a collection of rice accessions.Sequence analysis revealed that Xa2 and Xa31(t)from different rice cultivars are identical.These genes and their predicted proteins were found to be highly conserved,forming a group of Xa1 alleles.The XA1 alleles could be distinguished by the number of C-terminal tandemrepeats consisting of 93 amino acid residues and ranged from four in XA14 to seven in XA45(t).Xa1 allelic genes were identified in the 3000 rice genomes surveyed.On the other hand,iTALEs could suppress the resistance mediated by Xa1 allelic R genes,and iTALE genes were prevalent(95%)in Asian,but not in African Xoo strains.Our findings demonstrate the prominence of a defense mechanism in which rice depends on Xa1 alleles and a counteracting mechanismin which Xoo relies on iTALEs for BB. 展开更多
关键词 Xa2 Xa14 Xa45(t) TAL effector iTAL effector bacterial blight
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Bitter melon: a panacea for inflammation and cancer 被引量:15
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作者 Prasad R. Dandawate Dharmalingam Subramaniam +1 位作者 Subhash B. Padhye Shrikant Anant 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2016年第2期81-100,共20页
Nature is a rich source of medicinal plants and their products that are useful for treatment of various diseases and disorders. Momordica charantia, commonly known as bitter melon or bitter gourd, is one of such plant... Nature is a rich source of medicinal plants and their products that are useful for treatment of various diseases and disorders. Momordica charantia, commonly known as bitter melon or bitter gourd, is one of such plants known for its biological activities used in traditional system of medicines. This plant is cultivated in all over the world, including tropical areas of Asia, Amazon, east Africa, and the Caribbean and used as a vegetable as well as folk medicine. All parts of the plant, including the fruit, are commonly consumed and cooked with different vegetables, stir-fried, stuffed or used in small quantities in soups or beans to give a slightly bitter flavor and taste. The plant is reported to possess anti-oxidant, anti-inflammatory, anti-cancer, anti-diabetic, anti-bacterial, anti-obesity, and immunomodulatory activities. The plant extract inhibits cancer cell growth by inducing apoptosis, cell cycle arrest, autophagy and inhibiting cancer stem cells. The plant is rich in bioactive chemical constituents like cucurbitane type triterpenoids, triterpene glycosides, phenolic acids, flavonoids, essential oils, saponins, fatty acids, and proteins. Some of the isolated compounds (Kuguacin J, Karaviloside XI, Kuguaglycoside C, Momordicoside Q-U, Charantin, a-eleostearic acid) and proteins (a-Momorcharin, RNase MC2, MAP30) possess potent biological activity. In the present review, we are summarizing the anti-oxidant, anti-inflammatory, and anti-cancer activities of Momordica charantia along with a short account of important chemical constituents, providing a basis for establishing detail biological activities of the plant and developing novel drug molecules based on the active chemical constituents. 展开更多
关键词 Momordica charantia Bitter melon Anti-oxidant activity Anti-inflammatory activity Anti-cancer activity Na^n'al products
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2024 Adult Compendium of Physical Activities:A third update of the energy costs of human activities 被引量:11
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作者 Stephen D.Herrmann Erik A.Willis +10 位作者 Barbara E.Ainsworth Tiago V.Barreira Mary Hastert Chelsea L.Kracht John M.Schuna Jr. Zhenghui Cai Minghui Quan Catrine Tudor-Locke Melicia C.Whitt-Glover David R. Jacobs Jr. 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期6-12,共7页
Background:The Compendium of Physical Activities was published in 1993 to improve the comparability of energy expenditure values assigned to self-reported physical activity(PA)across studies.The original version was u... Background:The Compendium of Physical Activities was published in 1993 to improve the comparability of energy expenditure values assigned to self-reported physical activity(PA)across studies.The original version was updated in 2000,and again in 2011,and has been widely used to support PA research,practice,and public health guidelines.Methods:This 2024 update was tailored for adults 19-59 years of age by removing data from those≥60 years.Using a systematic review and supplementary searches,we identified new activities and their associated measured metabolic equivalent(MET)values(using indirect calorimetry)published since 2011.We replaced estimated METs with measured values when possible.Results:We screened 32,173 abstracts and 1507 full-text papers and extracted 2356 PA energy expenditure values from 701 papers.We added303 new PAs and adjusted 176 existing MET values and descriptions to reflect the addition of new data and removal of METs for older adults.We added a Major Heading(Video Games).The 2024 Adult Compendium includes 1114 PAs(912 with measured and 202 with estimated values)across 22 Major Headings.Conclusion:This comprehensive update and refinement led to the creation of The 2024 Adult Compendium,which has utility across research,public health,education,and healthcare domains,as well as in the development of consumer health technologies.The new website with the complete lists of PAs and supporting resources is available at https://pacompendium.com. 展开更多
关键词 ADULTS Energy expenditure EXERCISE MET Physical Activities
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Update on the management of gastrointestinal varices 被引量:19
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作者 Umesha Boregowda Chandraprakash Umapathy +7 位作者 Nasir Halim Madhav Desai Arpitha Nanjappa Subramanyeswara Arekapudi Thimmaiah Theethira Helen Wong Marina Roytman Shreyas Saligram 《World Journal of Gastrointestinal Pharmacology and Therapeutics》 CAS 2019年第1期1-21,共21页
Cirrhosis of liver is a major problem in the western world. Portal hypertension is a complication of cirrhosis and can lead to a myriad of pathology of which include the development of porto-systemic collaterals. Gast... Cirrhosis of liver is a major problem in the western world. Portal hypertension is a complication of cirrhosis and can lead to a myriad of pathology of which include the development of porto-systemic collaterals. Gastrointestinal varices are dilated submucosal veins, which often develop at sites near the formation of gastroesophageal collateral circulation. The incidence of varices is on the rise due to alcohol and obesity. The most significant complication of portal hypertension is life-threatening bleeding from gastrointestinal varices, which is associated with substantial morbidity and mortality. In addition, this can cause a significant burden on the health care facility. Gastrointestinal varices can happen in esophagus, stomach or ectopic varices. There has been considerable progress made in the understanding of the natural history, pathophysiology and etiology of portal hypertension. Despite the development of endoscopic and medical treatments, early mortality due to variceal bleeding remains high due to significant illness of the patient. Recurrent variceal bleed is common and in some cases, there is refractory variceal bleed. This article aims to provide a comprehensive review of the management of gastrointestinal varices with an emphasis on endoscopic interventions, strategies to handle refractory variceal bleed and newer endoscopic treatment modalities. Early treatment and improved endoscopic techniques can help in improving morbidity and mortality. 展开更多
关键词 PORTAL hypertension ESOPHAGEAL VARICES Gastric VARICES ECTOPIC VARICES ENDOSCOPY
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High-Resolution Genome-wide Association Study Identifies Genomic Regions and Candidate Genes for Important Agronomic Traits in Wheat 被引量:18
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作者 Yunlong Pang Chunxia Liu +22 位作者 Danfeng Wang Paul St.Amand Amy Bernardo Wenhui Li Fang He Linzhi Li Liming Wang Xiufang Yuan Lei Dong Yu Su Huirui Zhang Meng Zhao Yunlong Liangi Hongze Jia Xitong Shen Yue Lu Hongming Jiang Yuye Wu Anfei Li Honggang Wang Lingrang Kong Guihua Bai Shubing Liu 《Molecular Plant》 SCIE CAS CSCD 2020年第9期1311-1327,共17页
Wheat(Triticum aestivum)is a major staple food crop worldwide.Genetic dissection of important agronomic traits is essential for continuous improvement of wheat yield to meet the demand of the world's growing popul... Wheat(Triticum aestivum)is a major staple food crop worldwide.Genetic dissection of important agronomic traits is essential for continuous improvement of wheat yield to meet the demand of the world's growing population.We conducted a large-scale genome-wide association study(GWAS)using a panel of 768 wheat cultivars that were genotyped with 327609 single-nucleotide polymorphisms generated by genotyping-by-sequencing and detected 395 quantitative trait loci(QTLs)for 12 traits under 7 environments.Among them,273 QTLs were delimited to≤1.0-Mb intervals and 7 of them are either known genes(Rht-D,Vrn-B1,and Vrn-D1)that have been cloned or known QTLs(TaGA2ox8,APO1,TaSus1-7B,and Rht12)that were previously mapped.Eight putative candidate genes were identified for three QTLs that enhance spike seed setting and grain size using gene expression data and were validated in three bi-parental populations.Protein sequence analysis identified 33 putative wheat orthologs that have high identity with rice genes in QTLs affecting similar traits.Large r^2 values for additive effects observed among the QTLs for most traits indicated that the phenotypes of these identified QTLs were highly predictable.Results from this study demonstrated that significantly increasing GWAS population size and marker density greatly improves detection and identification of candidate genes underlying a QTL,solidifying the foundation for large-scale QTL fine mapping,candidate gene validation,and developing functional markers for genomics-based breeding in wheat. 展开更多
关键词 aestivum) WHEAT BREEDING
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Endoscopic ultrasound evaluation in the surgical treatment of duodenal and peri-ampullary adenomas 被引量:16
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作者 Lilian C Azih Brett L Broussard +4 位作者 Milind A Phadnis Martin J Heslin Mohamad A Eloubeidi Shayam Varadarajulu Juan Pablo Arnoletti 《World Journal of Gastroenterology》 SCIE CAS 2013年第4期511-515,共5页
AIM:To investigate endoscopic ultrasound(EUS) for predicting depth of mucosal invasion and to analyze outcomes following endoscopic and transduodenal resection.METHODS:Records of 111 patients seen at our institution f... AIM:To investigate endoscopic ultrasound(EUS) for predicting depth of mucosal invasion and to analyze outcomes following endoscopic and transduodenal resection.METHODS:Records of 111 patients seen at our institution from November 1999 to July 2011 with the postoperative pathological diagnosis of benign ampullary and duodenal adenomas were reviewed.Records of patients who underwent preoperative EUS for diagnostic purposes were identified.The accuracy of EUS in predicting the absence of muscular invasion was assessed by comparing EUS reports to the final surgical pathological results.In addition,the incidence of the post-operative complications over a period of 30 d and the subsequent long-term outcome(recurrence) over a period of 30 mo associated with endoscopic and transduodenal surgical resection was recorded,compared and analyzed.RESULTS:Among 111 patients with benign ampullary and duodenal adenomas,47 underwent preoperative EUS for 29 peri-ampullary lesions and 18 duodenal lesions.In addition,computed tomography was performed in 18 patients,endoscopic retrograde cholangio-pancreatography in 10 patients and esophagogastroduodenoscopy in 22 patients.There were 43 patients with sporadic adenomas and 4 patients with familial adenomatous polyposis(FAP)/other polyposis syndromes.In 38(81%,P < 0.05) patients,EUS reliably identified absence of submucosal and muscularis invasion.In 4 cases,EUS underestimated submucosal invasion that was proven by pathology.In the other 5 patients,EUS predicted muscularis invasion which could not be demonstrated in the resected specimen.EUS predicted tumor muscularis invasion with a specificity of 88% and negative predictive value of 90%(P < 0.05).Types of resection performed included endoscopic resection in 22 cases,partial duodenectomy in 9 cases,transduodenal ampullectomy with sphincteroplasty in 10 cases and pancreaticoduodenectomy in 6 cases.The main post-operative final pathological results included villous adenoma(n = 5),adenoma(n = 8),tubulovillous adenoma(n = 10),tubular adenom 展开更多
关键词 ENDOSCOPIC ultrasound DUODENAL periampullary ADENOMA ESOPHAGOGASTRODUODENOSCOPY Cholangio-pancreatography
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