Start Codon Targeted (SCoT) marker reveals genetic diversity of Dendrobium nobile Lindl., an endangered medicinal orchid species

Genetic variability in the wild genotypes of Dendrobium nobile Lindl. collected from different parts of Northeast India, was analyzed using a Start Codon Targeted (SCoT) marker system. A total of sixty individuals comprising of six natural populations were investigated for the existing natural genetic diversity. One hundred and thirty two (132) amplicons were produced by SCoT marker generating 96.21% polymorphism. The PIC value of the SCoT marker system was 0.78 and the Rp values of the primers ranged between 4.43 and 7.50. The percentage of polymorphic loci (Pp) ranging from 25% to 56.82%, Nei's gene diversity (h) from 0.08 to 0.15 with mean Nei's gene diversity of 0.28, and Shannon's information index (I) values ranging from 0.13 to 0.24 with an average value of 0.43 were recorded. The gene flow value (0.37) and the diversity among populations (0.57) demonstrated higher genetic variation among the populations. Analysis of molecular variance (AMOVA) showed 43.37% of variation within the populations, whereas 56.63% variation was recorded among the populations. Cluster analysis also reveals high genetic variation among the genotypes. Present investigation suggests the effectiveness of SCoT marker system to estimate the genetic diversity of D. nobile and that it can be seen as a preliminary point for future research on the population and evolutionary genetics of this endangered orchid species of medicinal importance.     

Identification and validation of a core set of informative genic SSR and SNP markers for assaying functional diversity in barley

A ‘core set’ of 28 simple sequence repeat (SSR) and 28 single nucleotide polymorphism (SNP) markers for barley was developed after screening six diverse genotypes (DGs) representing six countries (Afghanistan, Pakistan, Algeria, Egypt, Jordan and Syria) with 50 SSR and 50 SNP markers derived from expressed sequence tags (ESTs). The markers of the core set are single locus with very high quality amplifications, high polymorphism information content (PIC) and are distributed across the barley genome. PIC values for the selected SSR and SNP markers ranged between 0.32–0.72 (average 0.58) and 0.28–0.50 (average 0.42), respectively. To make the SNP genotyping cost effective, CAPS (cleaved amplified polymorphic sequence) and indel assays were developed for 23 markers and the remaining 5 SNP markers were optimized for pyrosequencing. A high coefficient of correlations (r = 0.96, P < 0.005) between the genetic similarity matrices of SSR and SNP genotyping data of the core set on diverse genotypes (DGs) and their similar groupings according to the geographical distribution in both SSR and SNP phenograms with high bootstrap values underline the utility and reliability of the core set. A comparative allelic and sequence diversity for SSR and SNP markers between the DGs and six elite parental genotypes (PGs) of mapping populations showed comparable diverse nature of two germplasm sets. However, unique SNPs and indels were observed in both germplasm sets providing more datapoints for analysing haplotypes in a better way for the corresponding SNP marker. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

A Study on Manganese Content in Soils and Leaves of Rubber Trees in Rubber Plantation Areas of China

The present paper deals with the status of manganese (Mn) in rubber trees on 110 rubber plantation at 46 counties in the rubber tree growing regions of China. The content of Mn in rubber tree leaves ranges from 31 to 2167 ppm, averaging 390 ppm which is higher than that in the leaves of normal rubber trees (150–300 ppm). Thus it can be concluded that the present status of Mn in China's rubber trees is higher. Nevertheless, the content of Mn of soil of rubber plantations in China varies significantly according to different soil types, fertilization and management. The difference between the highest and the lowest contents of total Mn could be as high as 140 times and an even greater difference of 200–1240-fold between the highest and the lowest contents of replaceable and reducible Mn has been observed. The storage of reducible Mn is generally insufficient in the soil. Therefore, the symptom of leaf yellowing due to deficiency of Mn has developed in rubber trees in certain parts of rubber tree growing regions in China. The essential oure for leaf yellowing of rubber trees is to raise Mn content in the tree by proper application of fertilizer. The procedures, dosage and timing of the fertilizer for leaf yellowing treatments are suggested.     

Determination of mineral content and organic matrix in bone samples using dual photon absorptiometry

An application of dual photon absorptiometry for measuring Bone Mineral Content (BMC) and the amount of organic matrix in bones in vitro is described. Dual photon absorptiometry was performed using a¹⁵³Gd source and a Gammatec GT 50 scanner. Although the method is well known in clinical research of osteoporosis and has previously been described, the fundamental principles of the method are demonstrated graphically as this paper is directed to a new audience. Measurements on 9 sections of autopsy and 11 sections of archaeological femoral bones showed that the sum of measured mineral and measured organic matrix was consistent with the weight of the sections with an accuracy of 1.1. and 3.3. per cent respectively. As a further control of the reliability of the method, nine sections were ashed by heating to 800°C for 14 hours. A high correlation could be demonstrated between BMC and ash-weight as well as between the organic matrix and the loss of weight during heating.     

西双版纳野生蔬菜中硒含量测定

为从天然植物中寻找富硒食品 ,分析了西双版纳地区常用的 6 8种野生蔬菜的硒含量。结果表明 ,6 8种野生蔬菜中硒平均含量为 0 0 85 3mgkg-1(干物质 ) ,低于栽培蔬菜中硒含量 ,其中富硒的 8种 ,低硒的 34种 ,极度低硒的 2 6种。 8种富硒含量为 0 84± 0 0 2 5— 0 37± 0 0 2 2mgkg-1(干物质 ) ,平均硒含量高于其它 6 0种野生蔬菜平均硒含量 35倍     

酸奶中乳酸菌含量的检测

目的检测酸奶发酵前后以及贮藏期间的乳酸菌活菌数及酸度变化,以对酸奶的质量进行控制.方法应用高层半固体琼脂试管法. 结果酸奶中乳酸菌含量极高,达2.65×1010个/ml以上,并随贮藏时间的延长而发生变化. 糖对酸奶的含菌量无明显影响.双菌酸奶比单菌酸奶含菌量高,常可达到倍增,pH值随发酵和贮藏进程而下降.结论高层半固体琼脂试管法操作简便、快速、准确、活菌检出率高.     

蒽酮法测定爬山虎果中糖类的含量

用蒽酮法测定爬山虎熟果中糖类的含量,波长620nm,检测线性范围0．01—0．5mg/ml,相关系数为0．9993,RSD＝5．64％回收率为98．56％。此方法操作简便准确、显色灵敏、重现性好、不受还原性物质的干扰。能测定总糖,还能测定可溶性糖,因此适合野生植物中糖类含量测定。     

广东鼎湖山自然保护区生物主模式标本内容分析

为了解鼎湖山物种分类学研究的历史,采用内容分析法对采自广东鼎湖山自然保护区的生物主模式标本信息进行了分析。结果表明,鼎湖山自然保护区的生物主模式标本共含202种生物(亚种或变种),分属3界10门20纲54目104科146属,其中植物界63种、动物界68种、菌物界71种。有194份标本(另8份无采集人信息)涉及77位采集人(或其团队),有67家机构的147人参与新种命名, 67种期刊的140条文献参与新种发表, 38个国内外机构保存了200种的标本,物种在30%的科、目、采集人、第1命名人、期刊和存放地各分配了约70%的数量,呈现类似"二八定律"所述的不平衡现象。1978至1997年是标本采集并命名的高峰期,标本采集率为55.45%、标本命名率为58.91%;植物标本的采集和命名早于动物和真菌。鼎湖山物种的橱柜时间(标本采集到命名间隔的时间)平均为7.56 a,且植物的长于动物和菌物。鼎湖山主模式标本生物的物种密度比邻近保护区的要高。     

Biochemical bio markers of pollution in Algerian mouse (Mus spretus) to assess the effects of the AznalcÓllar disaster on Doñana Park (Spain)

On April 25, 1998, a tailings dam of the Aznalcóllar pyrite mine partially collapsed and released to the Guadiamar river acidic water (pH &lt; 3) and mud containing toxic metals (Fe, Zn, Pb, As, Cu, Sb, Co, Tl, Bi, Cd, Ag, Hg, Sr), threatening the Doñana National Park, a Spanish wildlife reserve. To assess possible biological effects in terrestrial ecosystems, biochemical biomarkers have been assayed for the first time in Algerian mice (Mus spretus), a non-protected and free-living species, from several areas of Doñana and Guadiamar. Biomarkers assayed responded to different types of contaminants: I-metals and oxidant compounds (Se-glutathione peroxidase (SeGSHPx) and antioxidant activities, malondialdehyde (MDA), and glutathione redox status); II-Aromatic chemicals (ethoxyresorufin-O-deethylase (EROD) activity); III-Compounds of both types (glutathione-S-transferase (GST) activities). Before the Aznalcóllar spill (October 1997), mice from the 'Brazo de la Torre' had SeGSHPx and EROD activities close to animals from the Huelva Industrial Park, suggesting similar levels of oxidant and aromatic contaminants at both sites. Six months after the spill (October 1998), mice from the lower Guadiamar areas ('Cangrejo Grande' and 'Brazo de la Torre') also showed significant increase of soluble and microsomal GST activities, and altered levels of several antioxidant enzymes. Thus, the spilled chemicals could have induced further biological effects in mice from the exposed areas. Although no significant responses to contamination were found after the spill at Doñana core, further investigations should be carried out to monitor the situation.