Profiling and association mapping of grain metabolites in a subset of the core collection of Chinese rice germplasm (Oryza sativa L.)

In this study, metabolic profiles of a set of 48 rice germplasms from the Chinese core collection were obtained by gas chromatography and time-of-flight mass spectrometry (GC-TOF-MS). Forty-one metabolites were identified and relatively quantified according to the internal standard (IS). Wide ranges of variations for all metabolites were observed among rice accessions. The maximum/minimum ratios varied from 4.73 to 211.36. The metabolites were categorized into seven groups based on their chemical characteristics. Clustering analysis and a correlation network showed that most of the metabolites had variations among rice accessions in the same direction. Using 218 molecular markers, association mapping was conducted to identify the chromosomal loci influencing the concentrations of identified metabolites. Twenty markers were identified associating with the concentrations of 29 metabolites [-lg(P) > 3]. Allelic effects were investigated in detail in two markers (RM315 and RM541) as examples.     

Development of NIRS equations for food grain quality traits through exploitation of a core collection of cultivated sorghum

A sorghum core collection representing a wide range of genetic diversity and used in the framework of a sorghum breeding and genetics program was evaluated by near-infrared reflectance spectroscopy (NIRS) to predict food grain quality traits: amylose content (AM), protein content (PR), lipid content (LI), endosperm texture (ET), and hardness (HD). A total of 278 sorghum samples were scanned as whole and ground grain to develop calibration equations. Laboratory analyses were performed on NIRS sample subsets that preserved the core collection racial distribution. Principal component analysis performed on NIRS spectra evidenced a level of structure following known sorghum races, which underlined the importance of using a wide range of genetic diversity. Performances of calibration equations were evaluated by the coefficient of determination, bias, standard error of laboratory (SEL), and ratio of performance deviation (RPD). Ground grain spectra gave better calibration equations than whole grain. PR equation (RPD of 5.7) can be used for quality control. ET, LI, and HD equations (RPD of 2.9, 2.6, and 2.6, respectively) can be used for screening steps. Even with a small SEL in whole sample analysis, a RPD of 1.8 for AM confirmed that this variable is not easy to predict with NIRS.     

Assembling a core collection from the flax world collection maintained by Plant Gene Resources of Canada

Between 1998 and 2008, numerous projects were conducted by the Canadian national genebank, Plant Gene Resources of Canada, for the regeneration, characterization and evaluation of the whole flax (Linum usitatissimum L.) germplasm collection. The whole collection comprised 3378 accessions and, according to the passport data, several of these were probably genetically very similar or even identical. Therefore, a subset of 381 accessions was selected that represented the diversity found in the whole collection. Sampling accessions from the whole collection was made using characterization and evaluation data and followed six different methods: (1) For seven qualitative characters, each unique combination of character expression was represented by three accessions; (2) for quantitative characters, a fixed number of accessions representing the lowest and highest observed values was included; (3) for stem fibre content, disease ratings, seed vigour and drought tolerance, a fixed number of accessions with desirable performance was included; (4) a subset of the 57 most distinct accessions based on RAPD markers was included; (5) a subset of 40 pure lines that were created based on extreme low and high values for 1000 seed weight, seed oil content and fatty acid profiles was included; (6) a subset of fibre flax cultivars of known relevance in European flax breeding and another subset of flax cultivars of known relevance for North American linseed breeding were included. The goal was to maximize the diversity available in a limited number of flax accessions by preserving the range of variation present in the whole collection, while improving evenness. The core collection was assembled in response to requests by flax breeders. This paper compares distribution parameters in the whole and core collections.     

Establishment of sesame germplasm core collection in China

A sesame core collection containing 453 accessions was established by assessing genetic diversity of 4251 accessions collected in China. The accessions in the whole collection were grouped based on their origin, varietal and agro-ecological type. A computer program was used to cluster the data of 14 traits from the random small sample. Ward's method was chosen as the desirable method for clustering sesame germplasm resources. A set of technical methods for establishing core collection has been developed through determining the number of selected accessions based on the diversity distribution. The agronomic traits of the pre-selected core collection were investigated and tested in three ecological locations in China for two years. Among six qualitative traits, including plant type and flower color in a total of 5304 accessions, 97.85% was completely the same as the original data, and three quantitative traits, including growth period and plant height, were significantly and positively related with the original data. The representativeness assessment of the final core collection indicated that 35 phenotypes of 10 qualitative traits in the core collection were basically similar to those of the pre-selected core collection. Six feature values such as mean, standard deviation etc. of four quantitative traits including oil content and 1000-seed weight were close to those of the pre-selected core collection. The final core collection possessed a fair representativeness of the pre-selected core collection.     

An analysis of isozymic loci polymorphism in the core collection of the Polish Pisum genebank

The investigated material consisted of the core collection of the Polish Pisum gene bank at Wiatrowo and represented a described, monohybrid variation (type lines for characters/genes and their initial lines, tester lines with markers and lines from wild taxa, 266 accessions in total). A polymorphism in 18 isozymic loci was analyzed (Lap-1, Px-1, Aat-p, Aat-m, Aat-c, Pgm-c, Pgm-p, Gpi-c, Idh, Acp-1, Skdh, Est-1, Est-2, Est-3, Aldo, 6Pgd-p, 6Pgd-c, Dia-1). The practical outcome of the analysis was a selection of lines with a high number of fast or slow isozymic alleles, useful as tester lines with markers for chromosome mapping. A polymorphism was stated in all investigated loci with 2 to 4 alleles ranging from very fast, fast, slow to very slow. Fast and slow alleles occurred in all loci. In 11 loci the incidence of fast alleles was higher than slow ones. Conversly, slow alleles occurred more frequently than fast ones in 5 loci. Additionally, there was a low incidence of a very fast allele in 7 loci and of a very slow allele in 3 loci. A slow allele was rare in 2 loci. Primitive lines and land races were a source of these rare alleles. It is suggested to consider a frequent allele of a given locus found in a group of wild lines as a so-called wild type of Pisum.     

马蹄莲花期调控指标探析

对马蹄莲出花速度、环境温度平行观测及回归分析表明 ,马蹄莲出花天数与积温呈线性关系 ,花茎长度与有效积温呈对数关系 ,出花高度、售花高度与积温三者有较好关联 ,控制环境温度可有效控制花期     

Biomass production and related characters in the core collection of Pisum germplasm

Retention of residue on the soil surface following harvest is an effective method of reducing soil erosion from both wind and water. The pea crop produces small amounts of residue to effectively reduce soil erosion. Severe erosion occurs in pea production areas such as the Palouse Region of the US Pacific Northwest (PNW) when low residue crops such as spring pea or lentil are followed by fall-sown wheat. The current study was conducted to determine the range of total aboveground biomass (TAB), seed yield, and straw (residue) production from the plant identification (PI) accessions that comprise the core collection of Pisum germplasm. In addition, the potential for increasing seed yield and straw production simultaneously was evaluated. Three hundred and ninety PI accessions were screened in the field in 1996 and 1997. The variation for TAB, seed yield and straw production among the PI accessions exceeded that of the controls both years. Seed yield was positively correlated with straw production (r = 0.81, p< 0.01) indicating that seed and straw production can be increased simultaneously through positive selection for both traits. Significant favorable variation is present among accessions in the USDA core collection of Pisum germplasm which could be used to increase both seed yield and total biomass production of adapted breeding lines.     

淹水土壤中镉活性变化及其制约机理

近年来,面对全球土壤Cd污染日益严重的现状,国内外许多专家和学者对土壤中Cd的迁移转化进行了大量的探索和研究。但是,由于土壤自身的复杂性以及影响因素的多样性和不确定性,有关淹水土壤中镉(Cd)活性变化及其制约机理的研究常常出现截然不同甚至相反的报道。铁锰氧化物、碳酸盐、固相有机质、硫化物、DOM、阴离子(主要是Cl-和SO42-)和阳离子(如Al3+、Ca2+、Mg2+、Na+等)等繁多的制约因素及其制约机理使得Cd的土壤化学理论复杂化,也给土壤Cd污染的控制和治理带来困难。本文从Cd在土-水界面发生迁移转化的化学过程(吸附与解吸、沉淀与溶解和配位与螯合)入手,总结并阐述了淹水土壤中Cd活性的变化及其制约机理,同时对该领域的研究进行了展望,试图为淹水土壤中Cd活性的深入研究和Cd污染土壤的修复与治理提供参考。     

Oil and meal characteristics of core and non-core safflower accessions from the USDA collection

Germplasm evaluation of ex situ collections is needed to document collection characteristics, enhance utilization, and to determine collection needs. The objectives of this study were to (1) provide oil and meal evaluation information for a major portion of the United States Department of Agriculture (USDA) safflower (Carthamus tinctorius L.) collection, (2) compare ranges, variances and means between 203 core and 797 non-core accessions, and (3) determine if region of origin could be differentiated based on accession oil and meal characteristics. Means of the core and non-core accessions differed for % oil, palmitic acid, stearic acid, -tocopherols, and phenolic glucosides (both bitter and cathartic) (P<0.05). Differences between linoleic acid, oleic acid and -tocopherol means were not significant, and the variance between core and non-core accessions differed only for palmitic acid. Thus the core was not fully representative of the non-core accessions, but did capture a large fraction of the diversity in oil and meal factors present. Accessions from the Americas, China, South-West Asia, and South-Central Asia were differentiated using canonical discriminate analysis, but these regions overlapped to varying degrees with the E. European, Mediterranean, and E. African regions. Variation in % oil and fatty acids were generally more important than tocopherols and phenolic glucosides in differentiating accessions on a regional basis. The check cultivars Montola 2001 (high oleic) and Morlin (high linoleic) had oil and fatty acid content comparable to the maximums found in the collection. The ranges for tocopherols and phenolic glucosides among collection accessions, however, exceeded those of the cultivars, suggesting that collection accessions could be useful for genetic manipulation of these factors.     

Quantitative analysis of anticancer 3-deoxyanthocyanidins in infected sorghum seedlings

3-Deoxyanthocyanidins are structurally related to the anthocyanin pigments, which are popular as health-promoting phytochemicals. Here, it is demonstrated that the 3-deoxyanthocyanidins are more cytotoxic on human cancer cells than the 3-hydroxylated anthocyanidin analogues. At 200 microM concentration, luteolinidin reduced the viability of HL-60 and HepG2 cells by 90 and 50%, respectively. Sorghum is a major source of 3-deoxyanthocyanidins, which are present as seed pigments and as phytoalexins responding to pathogen attack. On the basis of the collision-induced dissociation spectra of luteolinidin and apigeninidin, an LC-MS/MS method, operating in multiple-reaction monitoring mode, was developed for the specific detection and accurate quantification of these compounds in complex mixtures, which may be difficult to analyze using absorbance measurements. The results demonstrated that inoculated sorghum seedlings could be utilized for convenient and large-scale production of 3-deoxyanthocyanidins. A quantity of almost 270 microg/g (fresh weight) of luteolinidin was produced 72 h after fungal inoculation of 1-week-old seedlings.     

应用重标度极差分析法（R/S）分析无定河流域水沙变化

河流水沙变化是降水、蒸发及下垫面条件改变的客观反映,揭示流域水沙演变规律及成因,可为水资源合理利用提供决策依据。应用R/S分析法对时变指数Hurst的计算及其检验,分析无定河流域赵石窑站和白家川站径流与输沙量时间序列的长程相关性。结果表明：两站的径流时间序列的Hurst指数分别为0.56、0.61,均大于0.5,呈现长程正相关;而两站的输沙量时间序列的变化存在差异,赵石窑站的输沙量时间序列有2个突变点,分别发生在1966和1979年,3个标度分布范围的Hurst指数分别为0.97、0.71和0.90,均明     

Surface sample collection and dust source analysis in northwestern China

Analysis of particle size shows that fractions of PM₅₀ (particle <50 μm in diameter) in the alluvial and lacustrine sediments, gobi deserts, shrub dunes, mobile dunes and deteriorated land are 37–99%, 5–7%, 0.26–36%, 0.05–0.4% and 51–62%, respectively. Mobile dunes, which are extensively distributed in northwestern China, are not a significant contributor to geogenic dust emissions due to their very low fractions of PM₅₀. Particle size distributions of different surface types, SEM, X-ray diffractogram and element content analysis all show that lacustrine sediment, shrub dune, gobi desert and deteriorated land are the most potential geogenic dust contributors. These analyses were also applied to the dust samples. Results and monthly dust disposition and dust event distributions show that the dust in the urban region of northwestern China, to a large extent, comes from non-geogenic contributors such as motor vehicle exhaust, coal burning and industrial emission.     

Characterization of core collection of lentil germplasm for phenology, morphology, seed and straw yields

Increasing and maintaining crop residues in predominantly cereal-based rotations of the US Pacific Northwest is critical to controlling soil erosion. The core collection of lentil (Lens culinaris Medik.) germplasm comprising 287 accessions was evaluated for variation in phenological, morphological and growth parameters including seed yields and residue amounts over a two-year period under conventional tillage and no-till conditions. The objectives of this study were (i) assess lentil genetic variation in germplasm for variation in biomass production and seed yield, (ii) assess the relationship of phenological and morphological traits with biomass and seed yield and (iii) identify high biomass producing germplasm for use as parents in the breeding program. Days to flowering and days to maturity ranged from 31 to 78 and from 71 to 106 days, respectively. Time to flowering in terms of cumulative heat units was a more efficient measurement than days to flowering. Plant height and plant canopy width had a significant association with total biomass, seed yield and residue amounts. Total biomass ranged from 788–6389 kg ha^–1 under conventional tillage, while the range under no-till conditions was 1045–6195 kg ha^–1. Most of the lines with higher biomass also produced the highest seed yields and residue amounts. Overall, only one accession produced more residue than `Laird'. In the more favorable environment of 1997, six accessions exceeded the control cultivars, `Laird' and `Indianhead', for residue amounts, and seven and twenty-four accessions exceeded control cultivars, `Pardina' and `Brewer', for seed yield. Results indicated that plant height, canopy width at maturity and seed yield explained most of the variation in biomass and residue production. Large seeded germplasm consistently had a longer reproductive growth period than small seeded accessions and had 17%, 7% and 21% more biomass, seed yield and residue, respectively. Our data indicated significant variation in lentil germplasm for biomass, seed yield and residue amounts to warrant their use in the breeding program.     

Variation in shoot and root characteristics and their association with drought tolerance in lentil landraces

Lentil (Lens culinaris Medikus subsp. culinaris), generally grown as a rainfed crop, is often subjected to drought. Drought tolerance is closely related to the distribution of root systems in the soil. We studied seedling shoot and root characters in a set of eight randomly selected lentil genotypes collected from Ethiopia, India, Iran, Syria and ICARDA. Each group of genotypes represents a specific adaptation to the environmental conditions associated with its area of origin. The genotypes were evaluated during two seasons (1997 –1999) under field conditions. Thirty-five-day-old seedlings grown in pots in the open air were assessed for stem length, stem weight, taproot length, lateral root number, total root length and total root weight. Combined analyses over 2 years showed that these characters exhibited significant genotypic variability. Stem length, taproot length and lateral root number were highly correlated, both amongst themselves and with yield. High heritability estimates provided reliability in screening based on these traits. Regression analysis showed that stem length alone accounted for 85% of the variance that occurred in seed yield per plant. Cluster analysis showed that the landraces that originated in Iran and Syria, and the breeding lines developed at ICARDA are distinctly different from the lentil accessions that originated in countries at more southerly latitudes (India and Ethiopia). However, of the total of 40 genotypes, only one line (ILL 6002) was strikingly different from all other test genotypes. This line exhibited significantly superior root and shoot traits and yield, and, therefore, is a valuable germplasm for breeding drought tolerant cultivars.     

Character analysis and numerical classification in a wheat collection from Sicily

Summary A study was undertaken using 48 characters observed in plants, spikes and seeds in order to determine the amount of information of different characters and their taxonomic importance in tetraploid wheat samples from Sicily. A classification of the material was also attempted using similarity indices.The most important characters appear: leaf pubescence, glume colour and length, and seed colour. Using all characters, similarity indices among samples were computed and a classification was worked out. This classification, which is very similar to those proposed by various scientists, produces hierarchical groups, showing different levels of merging, and offers very interesting hypotheses on the evolution of the Siciliandurum wheats.

---

Merkmalsanalyse und numerische Klassifikation an einer Weizen-Kollektion aus Sizilien

Zusammenfassung Untersucht wurden 48 Pflanzen-, Ähren- und Kornmerkmale an Proben tetraploider Weizen aus Sizilien, um den Informationsgehalt unterschiedlicher Merkmale und ihren taxonomischen Wert zu erfassen. Anhand von Ähnlichkeitsindices wurde auch eine Klassifikation des Materials vorgenommen.Als bedeutsamste Merkmale erscheinen: Blattpubeszenz, Spelzenfarbe und-länge und Kornfarbe. Auf der Grundlage aller Merkmale wurden Ähnlichkeitsindices zwischen den Proben errechnet und eine Klassifikation ausgearbeitet. Diese ist den Klassifikationen anderer Wissenschaftler sehr ähnlich, ergibt hierarchische Gruppen mit unterschiedlichem Ähnlichkeitsniveau und ermöglicht die Aufstellung einer interessanten Hypothese zur Evolution der sizilianischendurum- Weizen.

---

48 , . . : , , . . , .

     

The use of characterisation data to establish the Indian mungbean core collection and assessment of genetic diversity

A representative core set of well characterised Indian mungbean collection was developed using information on passport, characterisation and evaluation data. Initial diversity groups of the accessions comprising the whole collection were formed based on six major crop growing zones and a separate group for a few accessions from diverse exotic sources. Principal components score strategy was found to be most useful in maximising the selection inertia than strictly random sampling in all individual groups. A total of 152 accessions were extracted and the validity of their representativeness was established by comparing its diversity with that of the whole collection. Shannon diversity index for qualitative characters and certain statistical parameters for quantitative variables were used for measuring the diversity of the accessions in the core set and that of the whole collection. The representative core set was subjected to multivariate analysis for assessment of genetic diversity and also the variation patterns for discriminating among accessions to facilitate the users for easy accessibility, and effective and efficient utilisation of the material.     

Molecular and phenotypic characterization of a collection of white grain sorghum [Sorghum bicolor (L.) Moench] for temperate climates

Genetic Resources and Crop Evolution - Sorghum [Sorghum bicolor (L.) Moench] is a subsistence crop and the main food for populations in arid or semiarid regions and it is appreciated for the...