Genetic diversity and phylogenetic relationships among the annual Cicer species as revealed by isozyme polymorphism     

M. Labdi  L. D. Robertson  K. B. Singh  A. Charrier 《Euphytica》1996,88(3):181-188

Summary There are few estimates of genetic variability within and among populations of the nine annual Cicer species and for the wild species this information is based on few accessions. The present study was undertaken to examine genetic variation within and between annual Cicer species. One hundred and thirty-nine accessions of nine annual Cicer species were used for electrophoretic analysis at ICARDA. High levels of polymorphism in all eight wild annual Cicer species was found. This is in contrast to earlier research which had shown high polymorphism only in C. reticulatum. Cicer reticulatum had the highest proportion of polymorphic loci. However, for the cultigen, among 14 loci assayed, only two were polymorphic, ADH and PGD2. The nine species formed four phylogenetic groups based on the neighbor-joining method. The first group comprised C. arietinum, C. Reticulatum and C. echinospermum, the second C. bijugum, C. judaicum and C. pinnatifidum, the third C. chorassanicum and C. yamashitae; and the fourth group consisted of one species, C. cuneatum. The phylogenetic tree developed from the neighbor-joining technique illustrated that C. reticulatum is the probable progenitor of C. arietinum and that C. echinospermum split off from a common ancestor at an earlier stage in the evolutionary history of Cicer. Genetic diversity data showed that the greatest diversity was within C. reticulatum and the lowest with the cultigen, C. arientinum. With the exception of C. reticulatum, genetic diversity increased with genetic distance from the cultigen. Little geographic variation in genetic diversity was found.  相似文献   

Analysis of a backcross population from a multi-copy transgenic Brassica napus line     

Adrian D. Bavage  Emily Buck  Philip Dale  Catherine Moyes  Ian Senior 《Euphytica》2002,124(3):333-340

Brassica napus is one of the crops at the forefront of biotechnological development. The procedures used to produce transgenic varieties are all prone to generating plants with multiple transgene copies. There has been considereable interest in the behaviour of such multi-copy lines because gene dosage rarely appears to correlate simply with gene expression. Here we report the analysis of a population of 107 progeny from a B. napus transformant containing multiple copies of a GUS marker gene construct. A total of 12 GUS sequence copies were identified including one that was non-functional. The expression of GUS increased with increasing copy number but this increase only made up a small proportion of the total variation between lines. There was no evidence of interaction between the various GUS copies and they appeared to segregate independently. The variation between progeny lines indicated that the number of gene copies was not a good guide to the expression of the gene product and hence that the expression of the gene in progeny from a multiple-copy parent could not be predicted. The importance of these findings in relation to plant breeding and the risk assessment process is discussed. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Variation in cold tolerance and spring growth among Italian white clover populations     

Paolo Annicchiarico  Rosemary P. Collins  Flavio Fornasier  Ian Rhodes 《Euphytica》2001,122(2):407-416

Seven populations collected at different altitudes in northern Italy, two Ladino breeding populations and two control cultivars (AberHerald and Grasslands Huia) of white clover (Trifolium repens L.) were included in a series of experiments analysing: (i) levels of cold tolerance using artificial and field-based methods; (ii) relationships between these measures of cold tolerance; (iii) components of spring yield, various physiological traits, and their relationships with cold tolerance. Rates of seedling and growing point mortality in the populations over winter, assessed in separate field experiments, were closely related (r = 0.85). Grasslands Huia showed the highest death rates, and material originating from high altitudes the lowest. The LT₅₀ value, i.e., the temperature at which 50% of the growing points would die, estimated by an artificial freezing test, was significantly correlated with field-based measures of seedling (r = 0.64) and growing point (r = 0.84) mortality. The existence of these correlations is of potential interest for the development of indirect selection criteria for complex and expensive-to-evaluate traits such as winter survival in field plots. Besides being reliable, in this study the artificial assessment was also sensitive, providing a greater degree of separation of the populations means than field-based measures. Of the several physiological traits (water content,concentrations of water soluble and total non-structural carbohydrate, and water soluble protein content of stolons) measured at a mid-winter sampling date under field conditions, the only character showing significant variation between populations was soluble protein content. There was a slight trend for material with a higher protein content to exhibit greater field-based values of cold tolerance. High altitude populations tended to have low spring yields. The highest spring yield was found in one of the Ladino populations. The study identified two populations which combined, to differing extents, cold tolerance and spring yield characteristics that would be of potential use in breeding for specified agronomic/climatic zones. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Genetic diversity and taxonomic relationships within the genus Lens as revealed by allozyme polymorphism     

Morag E. Ferguson  Larry D. Robertson 《Euphytica》1996,91(2):163-172

Summary A survey of allozyme polymorphism at 11 loci was carried out on 439 accessions from the genus Lens. This comprised 153 Lens culinaris subsp. orientalis, 35 L. odemensis, 117 L. ervoides, 32 L. nigricans, 2 of a differentiated cytotype of L. nigricans and 100 landrace accessions of the cultivated lentil (L. culinaris subsp. culinaris), from 10 different countries. The aim of the survey was to determine intra-specific genetic diversity and species relationships, based on phylogenetic and phenetic analyses, particularly regarding the position of L. odemensis and the differentiated cytotype of L. nigricans. Diversity was described by three statistics. The level of diversity in the cultivated taxon was lower than in any of the wild species according to two of these statistics, the percentage of polymorphic loci and mean number of alleles per locus. For the third measure (Nei's mean genetic diversity) it was only greater than L. ervoides. Genetic diversity statistics of the wild species indicated differences in the nature of between-population genetic diversity within the different taxa. Phylogenetic analysis suggests that L. odemensis and L. ervoides evolved from a common ancestor, and L. culinaris subsp. orientalis subsequently evolved from L. odemensis. Phenetic analysis, however, places L. odemensis closer to L. culinaris subsp. orientalis than to L. ervoides. Nei's mean genetic distance of L. odemensis from both L. culinaris subsp. culinaris (0.204) and L. culinaris subsp. orientalis (0.110) was greater than the distance between them (0.062). This evidence is not conclusive in determining whether L. odemensis should retain its specific status. Further crossability studies should be carried out on a range of genotypes to assess the potential for gene flow. The evidence presented shows the differentiated cytotype of L. nigricans to be quite distinct from other L. nigricans accessions, both phenetically and phylogenetically. This indicates that the differentiated cytotype of L. nigricans may constitute a new taxon. Discriminant function analysis reveals that isozymes may be useful in validating species classification.  相似文献   

Analysis and Use of Interpool-Crosses (Mediterranean × Central European) in Faba Beans (Vicia faba L.) I. Performance of Mediterranean and Central European Faba Beans in Syria and Germany     

E. V. Kitttlitz    K. I. M. Ibrahim    P. Ruckenbauer  L. D. Robertson 《Plant Breeding》1993,110(4):307-314

The Central European and the Mediterranean Vicia faba gene pools carry different traits favourable for selecting cultivars with a high and stable yield performance. Interpool crosses, therefore, should provide interesting new basic material, although lack of adaptation of each “exotic” parent and linkage of genes may act against the introgression of favourable genes. In a first approach, five German and five Syrian parents (bred by ICARDA) of an interpool-crossing programme were tested in two years in both regions of origin. The Syrian cultivars proved to be fairly well adapted in the German trials, while the German cultivars were highly unadapted to the Syrian conditions. The advantage of interpool-crosses for both gene pools is discussed and recommendations on the further breeding strategy for adaptation of interpool-cross-progenies are given.  相似文献   

Patterns of variation in flowering and seed set of meadowfoam     

Canhong Cheng  Ian L. Gordon 《Euphytica》2003,131(1):105-111

Patterns of flowering and seed set were explored by principal component (PC) analysis of counts of fresh flowers, total flowers and seeds at four observation times. This pattern analysis was attempted because of the complicated rhythms of flowering and seed set over an extended period. The approach was considered superior to regressions (over time) for this data because of these pattern complexities, and because these were few time-nodes. Also it avoided the need to find optimum regression functions. Parsimony was achieved with a two-component ordination based on truncation at 70% of the total variance. The results for all characters showed that the first component concentrated on the middle period of flowering/seed set, and de-emphasized the early phase. The second component emphasized the extremities of the flowering/seed set span. The first component accounted for a large proportion of total variance (45.5% to 69.2%), which indicated its importance. The general meaning of the first component was ‘median flowering’, ‘general flower production’ and ‘median-to-late seed set’ for these characters fresh flowers, total flowers and seed set, respectively. The results showed that PC analysis successfully summarized the complex patterns of flowering/seed set and revealed the pattern differences between plants. It was apparent that no particular pattern of general flowering and seed set could be regarded as ‘typical’ in meadowfoam. It was confirmed that the population was diverse, this being typical of segregating plants within a randomly fertilized population. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

An assessment of the genetic relationship between sweet and grain sorghums, within Sorghum bicolor ssp. bicolor (L.) Moench, using AFLP markers     

Kimberley B. Ritter  C. Lynne McIntyre  Ian D. Godwin  David R. Jordan  Scott C. Chapman 《Euphytica》2007,157(1-2):161-176

Compared to grain sorghums, sweet sorghums typically have lower grain yield and thick, tall stalks which accumulate high levels of sugar (sucrose, fructose and glucose). Unlike commercial grain sorghum (S. bicolor ssp. bicolor) cultivars, which are usually F₁ hybrids, commercial sweet sorghums were selected as wild accessions or have undergone limited plant breeding. Although all sweet sorghums are classified within S. bicolor ssp. bicolor, their genetic relationship with grain sorghums is yet to be investigated. Ninety-five genotypes, including 31 sweet sorghums and 64 grain sorghums, representing all five races within the subspecies bicolor, were screened with 277 polymorphic amplified fragment length polymorphism (AFLP) markers. Cluster analysis separated older sweet sorghum accessions (collected in mid 1800s) from those developed and released during the early to mid 1900s. These groups were emphasised in a principle component analysis of the results such that sweet sorghum lines were largely distinguished from the others, particularly by a group of markers located on sorghum chromosomes SBI-08 and SBI-10. Other studies have shown that QTL and ESTs for sugar-related traits, as well as for height and anthesis, map to SBI-10. Although the clusters obtained did not group clearly on the basis of racial classification, the sweet sorghum lines often cluster with grain sorghums of similar racial origin thus suggesting that sweet sorghum is of polyphyletic origin within S. bicolor ssp. bicolor  相似文献   

Diversity and distribution of Victoria Land biota     

Byron J. Adams  Richard D. Bardgett  Diana H. Wall  Stuart Bamforth  Craig Cary  Laurie Connell  Jack W. Fell  Ian D. Hogg  Anthony O’Donnell  Rodney D. Seppelt 《Soil biology & biochemistry》2006,38(10):3003-3018

Understanding the relationship between soil biodiversity and ecosystem functioning is critical to predicting and monitoring the effects of ecosystem changes on important soil processes. However, most of Earth's soils are too biologically diverse to identify each species present and determine their functional role in food webs. The soil ecosystems of Victoria Land (VL) Antarctica are functionally and biotically simple, and serve as in situ models for determining the relationship between biodiversity and ecosystem processes. For a few VL taxa (microarthropods, nematodes, algae, mosses and lichens), species diversity has been intensively assessed in highly localized habitats, but little is known of how community assemblages vary across broader spatial scales, or across latitudinal and environmental gradients. The composition of tardigrade, rotifer, protist, fungal and prokaryote communities is emerging. The latter groups are the least studied, but potentially the most diverse. Endemism is highest for microarthropods and nematodes, less so for tardigrades and rotifers, and apparently low for mosses, lichens, protists, fungi and prokaryotes. Much of what is known about VL diversity and distribution occurs in an evolutionary and ecological vacuum; links between taxa and functional role in ecosystems are poorly known and future studies must utilize phylogenetic information to infer patterns of community assembly, speciation, extinction, population processes and biogeography. However, a comprehensive compilation of all the species that participate in soil ecosystem processes, and their distribution across regional and landscape scales is immediately achievable in VL with the resources, tools, and expertise currently available. We suggest that the soil ecosystems of VL should play a major role in exploring the relationship between biodiversity and ecosystem functioning, and in monitoring the effects of environmental change on soil processes in real time and space.  相似文献   

Usefulness of near-infrared reflectance (NIR) spectroscopy and chemometrics to discriminate fishmeal batches made with different fish species   总被引：1，自引：0，他引：1  

Cozzolino D  Chree A  Scaife JR  Murray I 《Journal of agricultural and food chemistry》2005,53(11):4459-4463

Near-infrared reflectance (NIR) spectroscopy combined with chemometrics was used to identify and authenticate fishmeal batches made with different fish species. Samples from a commercial fishmeal factory (n = 60) were scanned in the NIR region (1100-2500 nm) in a monochromator instrument in reflectance. Principal component analysis (PCA), dummy partial least-squares regression (DPLS), and linear discriminant analysis (LDA) based on PCA scores were used to identify the origin of fishmeal produced using different fish species. Cross-validation was used as validation method when classification models were developed. DPLS correctly classified 80 and 82% of the fishmeal samples. LDA calibration models correctly classified >80% of fishmeal samples according to fish species The results demonstrated the usefulness of NIR spectra combined with chemometrics as an objective and rapid method for the authentication and identification of fish species used to manufacture the fishmeal.  相似文献   

Pea (Pisum sativum L.) protease inhibitors from the Bowman-Birk class influence the growth of human colorectal adenocarcinoma HT29 cells in vitro   总被引：1，自引：0，他引：1  

Clemente A  Gee JM  Johnson IT  Mackenzie DA  Domoney C 《Journal of agricultural and food chemistry》2005,53(23):8979-8986

The Bowman-Birk trypsin-chymotrypsin inhibitor (BBI) from soybean has been described as a potential cancer chemopreventive agent. We have compared the effects of BBI with those of two variant recombinant pea (Pisum sativum L.) seed protease inhibitors, rTI1B and rTI2B, homologous to BBI but differing in inhibitory activity, on the growth of human colorectal adenocarcinoma HT29 cells in vitro. A significant and dose-dependent decrease in the growth of HT29 cells was observed using all protease inhibitors, with rTI1B showing the largest decrease (IC50 = 46 microM). Inclusion of the pan-caspase inhibitor, Boc-D-FMK, did not negate the effects of rTI1B or rTI2B in the cell assays. The relative effectiveness of rTI1B and rTI2B may correlate with a variant amino acid sequence within their respective chymotrypsin inhibitory domain, in agreement with a chymotrypsin-like protease as a potential target.  相似文献