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1.
Barley(Hordeum vulgare L.) is one of the earliest domesticated crop species and ranked as the fourth largest cereal production worldwide. Forward genetic studies in barley have greatly advanced plant genetics during the last century; however, most genes are identified by the conventional mapping method. Array genotyping and exome-capture sequencing have also been successfully used to target the causal mutation in barley populations, but these techniques are not widely adopted because of associated costs and partly due to the huge genome size of barley. This review summarizes three mapping cases of barley cuticle mutants in our laboratory with the help of RNA-sequencing. The causal mutations have been successfully identified for two of them and the target genes are located in the pericentromeric regions. Detailed information on the mapping-by-sequencing, mapping-and-sequencing, and RNA-sequencing assisted linkage mapping are presented and some limitations and challenges on the mapping assisted by RNA sequencing are also discussed. The alternative and elegant methods presented in this review may greatly accelerate forward genetics of barley mapping, especially for laboratories without large funding.  相似文献   
2.
In Europe, fossil fruits and seeds of Rhodoleia (Hamamelidaceae) have been described from the Upper Cretaceous to the Miocene, whereas no fossil record of Rhodoleia has been reported in Asia, where the modern species occur. Herein, 21 fossil leaves identified as Rhodoleia tengchongensis sp. nov. are described from the Upper Pliocene of Tengchong County, Yunnan Province, Southwest China. The fossils exhibit elliptic lamina with entire margins, simple brochidodromous major secondary veins, mixed percurrent intercostal tertiary veins, and looped exterior tertiaries. The leaf cuticle is characterized by pentagonal or hexagonal cells, stellate multicellular trichomes, and paracytic stomata. The combination of leaf architecture and cuticular characteristics suggests that the fossil leaves should be classified into the genus Rhodoleia. The fossil distributions indicate that the genus Rhodoleia might originate from Central Europe, and that migrated to Asia prior to the Late Pliocene. Additionally, insect damage is investigated, and different types of damage, such as hole feeding, margin feeding, surface feeding, and galling, are observed on the thirteen fossil leaves. Based on the damage frequencies for the fossil and extant leaves, the specific feeding behavior of insects on Rhodoleia trees appears to have been established as early as the Late Pliocene. The high occurrence of Rhodoleia insect herbivory may attract the insect-foraging birds, thereby increasing the probability of pollination.  相似文献   
3.
Based on gross morphological and cuticular study, two species of Ginkgo From the Lower Cretaceous Changcai Formation in Helong of Jilin. were identified from this area for the first time, including Ginkgo coriacea Florin and G. sibirica Heer. The study is significant for better understanding the paleophytogeographic, paleoecologic and stratigraphic characters of the Early Cretaceous Changcai flora.  相似文献   
4.
古大气CO2浓度重建方法技术研究现状   总被引:1,自引:0,他引:1  
温室气候引起的全球气候变暖越来越引起人们的关注,大气中不断上升的CO2浓度被认为是导致气候变暖的主要因素.地史时期大气CO2浓度变化与温室气候可能存在类似的关系,可提供参考,因而古大气CO2浓度重建是首要任务.总结近年来古大气CO2浓度重建的进展,重点介绍GEOCARB模型模拟、植物叶片气孔参数和同位素指针的方法和技术.GEOCARB模型是反映全球古大气CO2浓度长期变化的碳相关模型;气孔参数方法是使用气孔比例来估计古大气CO2浓度;同位素指针包括成壤碳酸盐、浮游植物有机质生物标记物、钙质浮游有孔虫、古苔藓植物等,其中成壤碳酸盐碳同位素方法使用最为广泛.国内只是在叶片参数研究方面有一些进展,古大气CO2浓度重建工作任重而道远.  相似文献   
5.
Consensus maps of cloned plant cuticle genes   总被引:1,自引:0,他引:1  
Plant cuticle,which covers the plant surface,consists of waxes and cutins,and is associated with plant drought,cold,and salt resistance.Hitherto,at least 47 genes participating in the formation of plant cuticle have been cloned from Arabidopsis thaliana,Oryza sativa,Zea mays,Ricinus communis,Brassica napus,and Medicago truncatula;and about 85% of them encode proteins sharing above 50% identities with their rice homologous sequences.These cloned cuticle genes were mapped in silico on different chromosomes of rice and Arabidopsis,respectively.The mapping results revealed that plant cuticle genes were not evenly distributed in both genomes.About 40% of the mapped cuticle genes were located on chromosome 1 in Arabidopsis,while 20% of the mapped cuticle genes were located on chromosome 2 but none on chromosome 12 in rice.Some cloned plant cuticle genes have several rice homologous sequences,which might be produced by chromosomal segment duplication.The consensus map of cloned plant cuticle genes will provide important clues for the selection of candidate genes in a positional cloning of an unknown cuticle gene in plants.  相似文献   
6.
从软体动物中的腹足纲、双壳纲以及节肢动物中的甲壳纲分别选取了3种中国沿海常见的品种——东风螺、弯竹蛏、斑节对虾,提取并分析它们的壳基质蛋白。利用液相色谱串联质谱(LC-MS/MS)技术对蛋白质组学进行分析发现特定的蛋白质具有明显的种属差异:①N66蛋白(一种碳酸酐酶)通常存在于弯竹蛏中,但不存在于东风螺和斑节对虾中,揭示N66蛋白质具有特异性,在未来的物种鉴定中可能具有重要的参考意义;②角质层蛋白AM1199和CP14.6存在于斑节对虾的表皮结构中,在东风螺和弯竹蛏中未检测到;③血蓝蛋白同时在3种动物外壳的基质蛋白中被鉴定出来,揭示了其在不同物种的外壳形成与发育过程中的重要作用。该研究为壳基质蛋白在软体动物或节肢动物外壳中的鉴定提供了基础,也为探索不同物种的生物矿化过程提供了重要参考。  相似文献   
7.
通过对南极磷虾蜕壳前后甲壳和残壳中氟含量变化特征的分析 ,对南极磷虾富氟的原因进行了研究。结合其它资料 ,本文还对南极磷虾的富氟来源及机制进行了探讨。研究结果表明 ,南极磷虾蜕壳后的残壳对氟具有二次吸收的功能和作用 ,其对氟的富集存在着与生命活动无关的机理。氟的积聚不仅来自海水 ,且主要是以离子交换吸附的方式进行。  相似文献   
8.
Based on gross morphological and cuticular study, two species of Ginkgo From the Lower Cretaceous Changcai Formation in Helong of Jilin. were identified from this area for the first time, including Ginkgo coriacea Florin and G. sibirica Heer. The study is significant for better understanding the paleophytogeographic, paleoecologic and stratigraphic characters of the Early Cretaceous Changcai flora.  相似文献   
9.
通过对甘肃窑街中侏罗统窑街组化石银杏以及现代银杏角质层有机质组分和碳同位素组成分析.表明银杏角质层有较强的抗风化能力.化石和现代银杏角质层有机质烷烃和甾萜类化合物组成十分相似。可以通过角质层的碳同位素组成等参数进行古环境重建,结果表明中侏罗世早期古环境较为温湿.到了中期后古气候逐渐变得干旱少雨,后期降雨量又逐渐增加,温度升高,植被发育。  相似文献   
10.
首次在吉林省延边地区长财煤矿早白垩世长财组发现蕉羽蕨叶属(Nilssoniopteris)。根据其外部形态及表皮构造等特征,鉴定并描述蕉羽蕨叶4个种,即:普里纳达蕉羽蕨叶Nilssoniopteris prynadae Samylina,平轴蕉羽蕨叶(新联合)N.platyrachis (Samylina) comb.nov.长叶蕉羽蕨叶?N.longifliadenko?和蕉羽蕨叶(未定种)Nilssoniopteris sp。  相似文献   
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