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Filip Jovanović, Dragica Obratov-Petković, Ivana Bjedov, Ivana Živanović, Sonja Braunović, Tatjana Ćirković-Mitrović, and Gordana Tomović

(Amaryllidaceae). Proc. Balkan Bot. Congr. 28:205–210 Sneath, P.H.A. Sokal, R.R. 1973 Numerical taxonomy. W.H. Freeman, San Francisco, CA Stern, F.C. 1956 Snowdrops and snowflakes. Roy. Hort. Soc., London, UK Stjepanović-Veseličić, L. 1975 Fam. Amaryllidaceae

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S. Pereira-Lorenzo, J. Fernández-López, and J. Moreno-González

Two-hundred and ninety-five trees sampled from seventy-five local chestnut (Castanea sativa Mill.) cultivars in northwestern Spain, which had been previously studied morphologically, were further analyzed for five isoenzyme systems, encoded by seven loci. Objectives of this study were to 1) describe the intracultivar and intercultivar variability by isoenzyme analysis and to compare it with the morphological variation and 2) establish a classification of the cultivars and to discuss its relation to the morphological classification. Variability within and among cultivars was detected, confirming the previous morphological results. The level of the observed heterozygosity in this Spanish population was higher than expected and also higher than that found in other European populations. Because of the great diversity discovered, this material seems to be worthy for introducing and maintaining in a germplasm bank. Nineteen main clusters were identified for the twenty-three most widely distributed cultivars. On the average, 61% of the trees belonging to a specific cultivar was included in the same cluster. The remaining 39% was scattered in other clusters, which indicates intracultivar variability. Therefore there is opportunity for selection within cultivars. Two clusters included three important cultivars each. This suggests possible synonymies. No correlation between morphological traits and the isoenzymic alleles was detected. The isoenzyme technique identified a higher number of cultivars increasing the information obtained with morphological traits. Correlations between the frequency of some of the alleles and the altitude and other environmental variables suggest that selection of the best adapted genotypes has occurred.

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Pedro Revilla and W.F. Tracy

Sweet corn is one of the most important vegetable crops in the United States, however the morphology and phylogeny of open-pollinated sweet corn cultivars has not been studied. Fifty eight open-pollinated sweet corn cultivars were characterized with thirty-four descriptors to provide information for breeders interested in broadening the genetic base of sweet corn. Principal component analysis and cluster analysis were performed to classify sweet corn cultivars based on morphology. Also, relationships among morphological variables in this set of cultivars were determined. The general ordination of cultivars followed an axis representing earliness, and plant, leaf, and tassel size, while ear and kernel attributes were less variable. The morphological variability among all of the widely used sweet corn cultivars, except `Country Gentleman', was not greater than the variability found among the `Golden Bantam' strains. Based on morphology, 52 of the cultivars could be considered as one race, which we propose be called `Northeastern Sweets'. These may be a subset of the race `Northern Flint'. Five of the remaining cultivars are from the north-central or southwestern United States and may represent races from those areas. The sixth cultivar is `Country Gentleman', a commercially important sweet corn cultivar. Due to the importance of `Country Gentleman' and the introgression of nonsweet germplasm into modern sweet corn, we believe that sweet corn should be defined based on its use as a vegetable and on the presence of one or more genes that increase sugar levels in the endosperm.

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Terri Woods Starman and Shane Abbitt

The objective was to distinguish between series of cultivars of Pelargonium xhortorum (zonal geranium), Pelargonium hybrids (seed geranium), and Pelargonium peltatum (ivy leaf geranium) using DNA amplification fingerprinting (DAF) demonstrating the utility of DAF for patent protection to prevent infringement of inventor's rights. Leaf tissue of 10 plants of each cultivar of seedling geranium was bulked for DNA extraction, and cutting and ivy geranium cultivars were bulks of five plants of each cultivar. Isolated DNA from different cultivars of a series were bulked together in their respective series. Seedling geranium series included Dynamo, Glamour, Multibloom, Orbit, Pinto, and Ringo 2000. Cutting geranium series included Designer and Showcase. Ivy geraniums were from the Guillou group. Amplification was with one of two octamer primers, followed by reamplifying with one of four different mini hairpin primers. Gels were visually scored for presence or absence of bands. The four primers generated 336 bands. The average number of bands (_1000 bp) per primer was 40. Twenty percent of bands were polymorphic and distinguished between each series of cultivars. Genetic relationships were evaluated by SAHN cluster analysis based on the distance estimator of Dice using the NTSYS-pc program (Numerical taxonomy and multivariate analysis system, version 1.8). Series were grouped according to species. Seedling geraniums were in one large group, the two cutting geraniums were grouped together and the ivy leaf geraniums were a separate branch.

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Terri Woods Starman and Shane Abbitt

The objective was to distinguish between cultivars and evaluate genetic relatedness of poinsettia (Euphorbia pulcherrima) using two methods of DNA fingerprinting—DNA Amplification Fingerprinting (DAF) and Arbitrary Signatures from Amplification Profiles (ASAP). Eleven red poinsettia cultivars were studied, including `Celebrate 2', `Darlyne', `Freedom Red', `Lilo', `Nutcracker Red', `Peterstar Red', `Petoy', `Red Sails', `Supjibi', `V-14 Glory', and `V-17 Angelika'. Amplification was with 10 octamer primers. Gels were visually scored for presence or absence of bands. The 10 primers generated 336 bands. The average number of bands (≈1000 bp) per primer was 34 ranging from 19 to 43. Thirty-one percent of bands were polymorphic and distinguished between each cultivar. The number of unique profiles varied from two to nine. Genetic relationships were evaluated by SAHN cluster analysis based on the distance estimator of Jaccard using the NTSYS-pc program (Numerical taxonomy and multivariate analysis system, version 1.8). The resulting dendrogram closely agreed with known pedigree data. ASAP analysis was used to further assess cultivar identification of two cultivars that were genetically and morphologically similar. Markers were found that separated `Nutcracker Red' and `Peterstar Red'. ASAP analysis separated cultivars within the Freedom series that DAF failed to distinguish. Two cultivars in the Freedom series, `Jingle Bells' and `Marble', were characterized from other cultivars in the series with ASAP.

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S. Pereira-Lorenzo, J. Fernández-López, and J. Moreno-González

Different chestnut (Castanea sativa Mill.) cultivars are at present grown in the region of Galicia, northwestern Spain, but no distinguishing traits among cultivars have been defined so far. The objectives of this research were to 1) describe the intra and intercultivar variability of chestnut cultivars; 2) define primary morphological traits to be useful for a simple morphological classification system of the cultivars; and 3) study the association between some environmental variables and the morphological traits. Seventeen morphological traits in a sample of 373 trees belonging to 82 local cultivars of chestnut were studied by methods of numerical taxonomy, principal component and cluster analysis. These traits were selected from 135 previously studied as having possible discriminating taxonomic value. Significant variability among cultivars and among trees within cultivars was found for most of the traits. The trees were grouped according to the degree of dissimilarity on the basis of the Mahalanobis generalized distance. Most of the clones collected under a specific cultivar name were included within the same cluster group enabling us to classify 53 of the cultivars studied. A hierarchical classification system that identifies eight cultivar groups is proposed based on four discriminating levels: nut size, fruit shape, male flower type and length of burr spines. Most of the correlations between the environmental variables and the morphological traits were no significant or had a low value. The lack of correlation between the environmental variables and nut size indicates that this important trait is under strong genetic control, it is not influenced by environmental conditions and it is consistent throughout the area sampled.

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Paul W. Bosland and Jit B. Baral

accession, it was scored “1”; if the band was not present, it was scored “0.” A computer software, numeric taxonomy, and multivariate analysis system, NTSYSpc, analyzed the RAPD markers ( Rohlf, 1998 ). The “Simqual” program of NTSYSpc uses an algorithm to

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Zhiyong Wang, Paul Raymer, and Zhenbang Chen

standard)] × known nuclear DNA (1.20 pg for PI 365032). Data analysis. Each SSR band was visually coded as present (1) or absent (0). The distance matrix and dendrogram were constructed using the Numerical Taxonomy Multivariate Analysis System (NTSYS

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Paul W. Bosland, Danise Coon, and Gregory Reeves

”; if the band was not present, it was scored as “0.” Band intensity was not taken into account. Molecular analysis was repeated. The RAPD markers were analyzed by the computer software, numeric taxonomy, and multivariate analysis system [NTSYSpc 2

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Mahdi Fendri, Isabel Trujillo, Ahmed Trigui, María Isabel Rodríguez-García, and Juan de Dios Alché Ramírez

.J. 1998 NTSYS-pc. Numerical taxonomy and multivariate analysis system. Version 2.00 Exeter Software Publishers Ltd Setanket, NY Sefc, K.M. Lopes, M.S. Mendonca, D. Rodrigues Dos Santos, M. Laimer Da