The record of cultivated rice from archaeobiological evidence in northwestern China 5000 years ago

Pollen, plant seeds and phytoliths from an AMS dated sediment profile at the Xishanping site indicate that the cultivation of rice might start no later than 5070 cal. a BP in the region of Tianshui, Gansu Province. It continued from 5070 to 4300 cal. a BP. This is so far the oldest and the most northwestern record of cultivated rice in Neolithic China, which extends the known region of prehistoric rice cultivation at least 2° longitude to the west. This finding provides important evidence for reconstructing the cultivation region of rice at 5000 a BP （an important time period）, and its spreading history in East Asia, during the Neolithic.     

Relationship between the temporal-spatial distribution of archaeological sites and natural environment from the Paleolithic Age to the Tang and Song Dynasties in the Three Gorges Reservoir of Chongqing area

The temporal-spatial distribution features including time distribution,horizontal and vertical spatial distribution of archaeological sites from the Paleolithic Age to the Tang and Song Dynasties in the Three Gorges Reservoir of Chongqing area are analyzed based on GIS spatial analysis.The successive pollen record of deposited peat stratum since the Paleolithic Age in the Dajiuhu Basin of Shennongjia is used in combination with the research of the historical environmental evolution to reconstruct the Paleoenvironment in the Three Gorges Reservoir of Chongqing area.Through the comparison of the temporal-spatial distribution of the archaeological sites and the natural environment,the relation between the distribution of the archaeological sites and the natural environment evolution and disaster changes from the Neolithic Age to the Tang and Song Dynasties has been discussed.Study shows that 677 archaeological sites from the Paleolithic Age to the Tang and Song Dynasties in the Three Gorges Reservoir of Chongqing area increase gradually from west to east and from high land to low land.Most of the sites are distributed along the river and aggregated at the confluence.Obviously,the altitudes of archaeological sites in the Paleolithic Age and the Neolithic Age are much higher than those of historical sites.The analysis suggests:(1)the human beings of every times would like to choose the first or the second river terrace as living sites which are nearer to the water source and are easier to with- stand flood.The pre-historical sites of earlier ages are often located at the higher altitude place because of the tectonic uplift and downcutting of rivers since Holocene.(2)Due to the rugged terrain in Chongqing area,most of the sites are located along the river sides,for example,the wide river valley and terrace,which could provide wider living space caused by the lateral erosion and deposition of the river course.(3)The early residents mainly relied on fishing,hunting and agriculture,and the rugged terrain of the mountaino     

Ancient DNA sequences of rice from the low Yangtze reveal significant genotypic divergence

Rice (Oryza sativa) was first domesticated in the lower and middle Yangtze regions of China, and rice remains have been found in many Chinese archaeological sites. Until now, only phenotypic archeobotanical evidence, such as the spikelet bases of ancient grains, has been used to speculate on the domestication process and domestication rate of rice. In this study, we sequenced 4 genomic segments from rice remains in Tianluoshan, a site of the local Hemudu Neolithic culture in the low Yangtze and two other archaeological sites (~2400 and 1200 BC, respectively). We compared our sequences with those of the current domesticated and wild rice (O. rufipogon) populations. At least two genotypes were found in the remains from each site, suggesting a heterozygotic state of the rice seeds. One ancient genotype was not found in the current domesticated population and might have been lost. The rice remains belonged to the japonica group, and most if not all were japonica-type, suggesting that the remains might be at an early stage of indica-japonica divergence or an indica-japonica mixture. We also identified sequences with significant similarity to those from species of Sapindales, Zygophyllales, and Brassicales, which is consistent with the identification of other plant remains in the Tianluoshan site and the common rice field weeds such as mustards in southern China.     

水稻的起源与驯化——来自基因组学的证据

 水稻是世界上最重要的粮食作物, 约1 万年前开始被驯化。由于水稻与其祖先野生种存在一定的遗传分化, 水稻的起源和驯化问题长期存在争议。本文综述了水稻起源和驯化方面的研究成果, 特别是近年来基因组学方面的证据, 认为水稻2 个亚种独立起源于野生祖先种内很早就分化的不同类群, 但一些驯化基因--控制重要农艺性状的基因, 可能首先在一个亚种中被驯化, 然后通过基因渐渗, 扩散到另一个亚种中。因此, 水稻驯化的关键是研究驯化基因的起源和扩散方式。随着大规模基因组测序技术的发展和相应数据分析方法的建立, 在全基因组水平对水稻及其祖先进行大规模分析, 已成为揭示水稻起源与驯化之谜的必由之路。     

宅基地使用权继承的法理学思考

我国当前立法并未认可农村宅基地使用权的继承制度，这就人为割裂了房地一体的逻辑，也与其用益物权的属性产生了冲突。宅基地使用权继承合法化有利于法的秩序价值、公平价值的实现，并能体现法律的适应性。同时，应采取一定的限制性继承制度以保证继承人个体利益与集体经济组织、社会整体利益之间的利益平衡。     

我院抗精神病药用药剂量五年前后比较

目的 了解我院分裂症患者的药物使用情况,为临床合理用药提供指导.方法 采用时点调查法,调查一天在我院住院的所有分裂症患者的一般资料及用药情况,与五年前进行比较分析.结果 在分裂症患者中,抗精神病药物用药剂量与五年前相当.结论 本次调查的所有住院分裂症患者的抗精神病药物用药剂量,与五年前相比无统计学意义.     

我院抗精神病药用药剂量五年前后比较

目的了解我院分裂症患者的药物使用情况，为临床合理用药提供指导。方法采用时点调查法，调查一天在我院住院的所有分裂症患者的一般资料及用药情况，与五年前进行比较分析。结果在分裂症患者中，抗精神病药物用药剂量与五年前相当。结论本次调查的所有住院分裂症患者的抗精神病药物用药剂量，与五年前相比无统计学意义。     

我院抗精神病药用药剂量五年前后比较

目的了解我院分裂症患者的药物使用情况,为临床合理用药提供指导。方法采用时点调查法,调查一天在我院住院的所有分裂症患者的一般资料及用药情况,与五年前进行比较分析。结果在分裂症患者中,抗精神病药物用药剂量与五年前相当。结论本次调查的所有住院分裂症患者的抗精神病药物用药剂量,与五年前相比无统计学意义。     

正视轻声衰颓现象重新审订轻声词

随着社会的发展,轻声词出现了衰颓现象,其原因主要有三方面:轻声词自身的不稳定性、北京语音接受其他地方语音的影响、汉语国际化.因此,迫切需要重新审订轻声词.重新审订轻声词需遵循辨义原则、约定俗成原则,还应统一标准.     

褐飞虱取食水稻幼苗cDNA文库的构建及筛选

以褐飞虱取食 3 2 h的水稻幼苗为材料构建了 c DNA文库 ,初始文库含 3 .2× 1 0 6 个克隆 ,重组率为 86%,取 1 .0× 1 0 6个克隆子扩增一次 ,收集到 80 m L滴度为 1 .2× 1 0 9pfu/ m L的扩增文库 .随机挑取 2 0个克隆以 T7和 M1 3 reverse为引物进行 PCR扩增 ,以鉴定插入片段的大小 ,结果发现多数片段的长度在 1～ 4.0Kb左右 ,少数片段在 4Kb以上 ,个别片段在 6Kb左右 .以在受褐飞虱取食的水稻幼苗中特异表达的 ESTBp Hi0 0 8为探针 ,筛选 c DNA文库 ,得到该基因的 c DNA全长     

秋水仙素诱导水稻幼穗愈伤组织创制同源四倍体种质的研究

以普通二倍体水稻亲本为材料,用秋水仙素进行水稻的多倍体化诱导,创制同源四倍体水稻三系亲本材料并对其进行鉴定. 结果表明在MS+2,4 D 1.0 mg/L+ KT0.2 mg/L+ IAA0.2 mg/L 和500 mg/L的秋水仙素处理下,水稻愈伤组织染色体加倍效果最好,平均加倍频率可达25.26%.其中,材料CDR22和IR26诱导较易成功,加倍频率分别达到75%和26.5%;相对材料94109 1.3%加倍频率和冈46B 10.8%加倍频率,诱导率差异极显著. 对水稻四倍体材料进行形态学鉴定结果表明     

New technology to examine and improve the purity of hybrid rice with herbicide resistant gene

The herbicide resistant bar gene has been widely used as selectable marker genes in the study on plant genetic transformation. Owing to the integration of the gene into rice genome, transgenic rice was resistant to the herbicide Basta. Therefore, selection of transgenic plant md genetic analysis became easier. In the studies, bar gene was introduced as a genetic marker gene into ria restore lie variety of two-line or three-line. Combined with conventional breeding method, the good herbicide resistant individual plant was derived as the new restorc line for hybrid combination. After sprayed with Basta at seeding phasc. the real hybrid rice that hnd herbicide resistance could grow normally, while the fnke hybrid rice and weeds, having no bar gene, were killed by herbicide. The method described above helped rapidly to examine and improve the purity of hybrid rice.     

稻草木质素的硫酸法提取与表征

用硫酸法提取农作物废弃物稻草中的木质素,采用质量分数72%的硫酸,以15(mg)∶1(L)的液固单位比,室温下反应2 h,得到产率9.23%的木质素.利用扫描电镜(SEM)、综合热分析、傅里叶红外光谱(FTIR)和氢核磁共振波谱(¹H-NMR)分析手段表征木质素的物理性质和化学结构,结果表明:木质素呈表面粗糙且有大量孔隙的不规则块状结构,在175~700 ℃内发生热解,分子结构中存在着大量羟基、羰基和醚键等活性官能团,属于对羟基苯基-愈创木基-紫丁香基型木质素.     

Resistance to rice blast (Pyricularia oryzae) caused by the expression of trichosanthin gene in transgenic rice plants transferred through agrobacterium method

The gene of trichosanthin has been transferred into rice plants through agrobacterium method. The single copy insertion and the expression of foreign gene have been proved in regenerated plants. In antifungal assay the degrees of rice blast (Pyricularia oryzae) infection of the transgenic plants expressing trichosanthin and expressingGUS gene as control have been evaluated. The differences such as the time of disease symptom observed, the number of infected plants and damaged leaves, the growth of infected plants of the two transgenic plants after being inoculated by rice blast (Pyricularia oryzae) are significant. The transgenic plants with trichosanthin gene grew faster than the plants withGUS gene, even when humidity environment was removed. The results show that the transgenic plants that expressed trichosanthin are able to delay the infection of rice blast compared with the plants as control. In addition, no damage caused by the expression of trichosanthin gene in transgenic plants has been observed.     

籼稻9311成熟胚再生体系

建立9311水稻高效再生体系,将有利于人们以9311水稻为受体进行遗传改良及籼型水稻基因功能的研究．报道了9311成熟胚高效再生途径．以9311成熟胚为外植体,设计了5类（N6DP,N6DA,MSDP,MSDA和MSDAP）共13种不同愈伤组织诱导培养基,比较了9311成熟胚在不同培养基中愈伤组织的诱导以及初始愈伤组织被继代后的表现．结果显示：9311成熟胚在添加2,4-二氯苯氧乙酸（2,4-D）的所有培养基中都能够形成愈伤组织;将最初被诱导的愈伤组织进行继代培养,在前4类培养基上诱导的初始愈伤组织,不论被分别继代于与原培养基成分相同的新鲜培养基上,还是被继代于MSDAP培养基上,继代后的愈伤组织都相继褐化死亡,而将从MSDAP培养基上诱导的初始愈伤组织继代在MSDAP培养基上,愈伤组织很少出现褐化现象,并且能够较快地增殖．由此表明,MSDAP培养基是9311成熟胚合适的愈伤组织诱导培养基和增殖培养基．采用MSDAP培养基培养,9311水稻成熟胚愈伤组织诱导率达87．5％．分化率为46．7％．再生植株的比例为23．3％、     

旱涝快速转换对分蘖后期水稻生理特性的影响

采用测筒试验研究了水稻分蘖期旱涝快速转换前后的光合特性和生理活性.结果表明:旱涝快速转换后轻度淹涝处理,叶片的光合速率(Pn)、蒸腾速率(Tr)和气孔导度(Cs)得以逐渐恢复;重度淹涝叶片的Pn,Tr和Cs均显著低于对照,且随时间的推移呈下降趋势.旱后轻涝和旱后重涝处理的叶绿素a、叶绿素b、类胡萝卜素(CAR)的质量分数和叶绿素(a b)的质量分数均低于对照.旱涝快速转换后轻度淹涝处理丙二醛(MDA)的质量摩尔浓度与对照差异不显著,而重度淹涝处理则极显著高于对照.旱后轻涝处理有利于根系活力(TTC还原强度)的提高,表现出超补偿效应,而旱后重涝处理的根系活力则显著降低.     

Molecular cloning of rice cDNAs related to pollen development using the subtraction hybridization technique

The meiotic stage of pollen mother cell is a very important stage in controlling the development and formation of pollen. In order to clone the rice cDNA(s) of this stage, a normal rice, Annong N and its thermosensitive mutant, Annong S-1 were used as the plant material. The mRNA has been extracted from the young panicle at the meiotic stage. By using the cDNA subtraction hybridization technique, three cDNA fragments, RP-1, RP-2 and RP-3 have been successfully cloned from Annong N. Northern blot analysis reveals that the mRNA of these three clones are expressed only in anthers, and not leaves. The mRNA levels of these clones are lower in anthers of Annong S-1 than in Annong N. Furthermore, the amount of mRNA extracted from anthers of Annong S-1 growing under high temperature (28℃) is lower than plants growing at lower temperature (25℃). Sequence analysis and homology search indicate that these three clones display no similarity to the current database. It is concluded that the three novel cDNA cloned are related to pollen development in rice.     

Genetic diversity of rice cultivars （Oryza sativa L.） in China and the temporal trends in recent fifty years

Public concern is often expressed at cultivars because the domestication and modern plant breeding have led to a reduction in the genetic diversity of crops and loss of genes, which could result in crops' genetic vulnerability to changes in the spectrum of pestssity of varieties in this zone is very important to the whole rice production in China. REZV, a important japonica rice production areas with more than 278 thousands ha rice which was about 71% of rice area in north China, accounted fo…