Search Results

You are looking at 1 - 10 of 38 items for :

  • "genetic fingerprinting" x
  • Refine by Access: All x
Clear All
Free access

L.S. Boiteux, M.E.N. Fonseca, and P.W. Simon

Seven plant genomic DNA purification protocols were evaluated for genetic fingerprinting analysis using six tissues obtained from inbred carrot (Daucus carota L.) lines. Evaluations included 1) DNA yield, 2) DNA purity, 3) DNA cleavage with HindIII, 4) DNA integrity, and 5) DNA suitability for amplification in a random amplified polymorphic DNA (RAPD) system. Significant differences were observed among tissues and purification methods for the total amount of DNA. An extraction method using CTAB buffer + organic solvents gave the best results in DNA yield, purity, and HindIII cleavage when compared with the other six nonorganic extraction methods. Of the tissues examined, flowers yielded the most DNA (average value = 115 ng of DNA/mg of fresh tissue); followed by seeds (54 ng·mg-1), fresh leaves (48 ng·mg-1), lyophilized leaves (40 ng·mg-1), calli (22 ng·mg-1), and tap roots (4 ng·mg-1). For most of the preparations, the DNA showed no traces of degradation. However, DNA preparations were not consistently accessible to HindIII cleavage in all tissue-extraction method combinations. Uncut DNA was observed chiefly in extractions from flowers and fresh leaves suggesting a tissue-specific adverse effect on restriction endonuclease activity. Differences in RAPD band (amplicon) intensity and number were observed across tissues and DNA extraction methods using identical PCR conditions for RAPD. Callus was the best type of tissue for RAPD-based fingerprinting yielding a consistently higher number of more intense amplicons when compared to the other tissues. In flowers and seeds, only DNA obtained with the CTAB extraction method could be amplified. Polymorphisms deviating from genetic expectations were mainly observed in root and fresh leaf DNA, indicating that some RAPD markers may not present satisfactory levels of reproducibility. Judicious and uniform selection of DNA purification method as well as tissue source for DNA extraction are, therefore, important considerations for reliable RAPD-based DNA fingerprinting analysis in carrot. In addition, our studies allowed the identification of a better combination of procedures for use in routine manipulations of carrot DNA such as RFLP-RAPD-based cultivar fingerprinting, molecular mapping, screening of transgenic plants, construction of genomic libraries, and gene cloning.

Free access

Daniel J. Bell, Lisa J. Rowland, James J. Polashock, and Frank A. Drummond

Little is known of the genetic structure and variability of wild fields, or of the dramatic differences in yield among clones (genetic individuals), of lowbush blueberry (Vaccinium angustifolium Ait.), Maine's most economically important fruit crop. Express sequence tag-polymerase chain reaction (EST-PCR) markers that were originally developed for genetic mapping purposes in highbush blueberry (Vaccinium corymbosum L.) are shown here to be valuable for genetic fingerprinting and relationship studies in the related species, V. angustifolium. As part of an interspecific genetic relationship study, 14 genotypes, including at least two specimens of each of four closely related Vaccinium L. species (V. pallidum Ait., V. corymbosum, V. boreale Hall & Aald., and V. myrtilloides Michx.) and the only four pedigreed cultivars of V. angustifolium, grouped out as expected in a genetic similarity dendrogram (matrix “r” correlation = 0.91). This work is ultimately aimed at using these markers in exploring how genetic relationship affects yield among proximal and distant breeding individuals via controlled field hand crosses. To help address this issue, a separate group of six individuals of V. angustifolium from two managed fields were also genotyped using the EST-PCR markers. The markers were very effective at intraspecific discrimination of individuals within the same field.

Free access

Paul Skroch and Jim Nienhuis

The genetic variation in a population of one hundred Snap Bean varieties, including processing and garden types, was studied using RAPD markers. All one hundred genotypes were distinguished by unique combinations of banding patterns. These unique “fingerprints” were tested for repeatability. Certain bands were very reliable and can be used for varietal identification. The RAPD marker data was also used to estimate genetic relationships among a subset of the one hundred lines. The results of the analysis agreed with known pedigree information. These markers will allow more precise monitering and control of germplasm by those who are involved with the breeding and production of superior seed.

Free access

Mark S. Strefeler, Elizabeth Darmo, Roger L. Becker, and Elizabeth J. Katovich

Isozyme markers were used to identify several cultivars of purple loosestrife (Lythrum spp.) and interspecific hybrids. There were three zones of activity for phosphoglucomutase (PGM) and phosphoglucoisomerase (PGI) and two zones for malate dehydrogenase (MDH) in purple loosestrife cultivars. Allelic constitution could not be characterized due to the polyploid nature of purple loosestrife and the possibility of intergenic dimerization. Coefficients of genetic similarity were used to estimate the degree of relationship between purple loosestrife cultivars. Cluster analysis indicated that seven cultivars originating from L. salicaria L. were not distinguishable from eight cultivars originating from L. virgatum L., indicating possible limitations of isozyme analysis for cultivar differentiation based on species origin. All but two cultivars (`Morden Gleam' and `Morden Rose') could be distinguished from one another by isozyme phenotype. This result suggests that isozymes may be useful for cultivar fingerprinting if additional isozyme systems could be resolved. `Robert' appeared morphologically heterogeneous, and plants could be differentiated based on isozyme banding patterns. Also, two putative clones of `Stichflamme' (one marketed under its English synonym `Fire Candle') possessed distinct isozyme phenotypes, indicating a lack of clonal integrity.

Free access

Claudio Cantini, Antonio Cimato, Antonella Autino, Alessandro Redi, and Mauro Cresti

intracultivar diversity. Materials and Methods One hundred fifty-four accessions of Tuscan olive germplasm kept in the National Research Council of Italy collection at the Santa Paolina experimental farm in Follonica, Italy, were available for genetic

Free access

Jonathan Magby, Gayle M. Volk, Adam Henk, and Steve Miller

. Apple cultivars have been reliably identified using genetic fingerprinting techniques (microsatellites) because they have a high level of polymorphism, are codominant, and are inherited in a Mendelian fashion ( Wünsch and Hormaza, 2001 ). The goal of

Free access

Jean-Guy Parent and Danièl Pagé

Characterization and identification of 13 red raspberry (Rubus idaeus L.) and two purple raspberry (R. × neglectus Peck) cultivars were obtained by nonradioactive genetic fingerprinting. DNA from leaves was digested with Hae III and Hin f I restriction enzymes and probed with alkaline phosphatase-labeled oligonucleotide. All tested cultivars could be identified by a unique band pattern. No differences were noted within cultivars when the reproducibility of the fingerprints was evaluated by analyzing the effects of age of the raspberry plantation, developmental stage during the growing season, or position of the sampled leaf on stem. These results suggest that simple nonradioactive DNA fingerprinting can be routinely used to identify raspberry cultivars.

Free access

Elizabeth J. Parks and James W. Moyer

Fingerprinting using molecular markers is a highly effective method of cultivar identification that is a powerful aid to traditional methods based on morphology. Amplified fragment length polymorphism (AFLP) is a robust and reliable method for generating molecular markers that has been used to evaluate many crops for a variety of applications. In this study, AFLP was used to develop and validate robust genetic fingerprints for poinsettia (Euphorbia pulcherrima Willd. ex Klotzch) cultivars. Polymorphism selection was completed to facilitate the identification of useful polymorphisms and minimize future fingerprinting costs and time. Poinsettia is a highly variable crop subject to genetic drift and variable cultivars. Validation of polymorphisms to remove those associated with intracultivar variation improved the reliability of the fingerprinting. The result was a poinsettia AFLP database that defines the genetic fingerprints of 104 cultivars. Cluster analysis illustrated differentiation of most poinsettia cultivars tested. Selection of a subset of AFLP polymorphisms resulted in clustering of cultivars according to known origin and breeding program. This method has applications not only for cultivar identification for cultivar protection, and maintenance of cultivar uniformity, but also has the potential application of developing markers for important traits.

Free access

Stan C. Hokanson, Kelvin G. Grant, Elizabeth L. Ogden, and Lisa J. Rowland

Commercial strawberry plantings in the mid-Atlantic region are often quickly infected with one or more aphid-transmitted viruses, resulting in the loss of plant vigor, stunting, lowered yields, etc. To produce virus-free plant material for the strawberry industry and for cultivar development programs, heat therapy and/or meristem tip culture protocols are generally employed. One of the problems associated with meristem culturing is the potential for somaclonal mutations to occur in the meristem or surrounding proliferating tissue. As a result, distinct “bud lines” displaying functionally insignificant to distressingly high levels of phenotypic variation can arise from individual meristems. It would be desirable to differentiate these off-types by genetic fingerprinting to maintain trueness-to-type. Randomly amplified polymorphic DNA (RAPD) markers were evaluated for the potential to differentiate six pairs of strawberry bud lines that exhibit slight to fairly extreme levels of phenotypic variation. Reproducible RAPD marker profiles were generated using 10 primers in amplification reactions with genomic DNA obtained from multiple extractions. While five of the bud line pairs remained indistinguishable, three primers distinguished two variants of the Mohawk cultivar that are now in existence in the strawberry industry. Results suggest that typical somaclonal variation produced in the meristem culture process is of a magnitude that is not readily detectable with the RAPD protocol. The two Mohawk lines were probably produced by a higher magnitude mutation event than generally occurs or a cultivar mix-up.

Free access

Kang Hee Cho, Seo Jun Park, Su Jin Kim, Se Hee Kim, Han Chan Lee, Mi Young Kim, and Jae An Chun

Blueberry cultivars have traditionally been identified based on the evaluation of sets of morphological characters; however, distinguishing closely related cultivars remains difficult. In the present study, we developed DNA markers for the genetic fingerprinting of 45 blueberry cultivars, including 31 cultivars introduced from the United States Department of Agriculture. We obtained 210 random amplified of polymorphic DNA (RAPD) markers using 43 different primers. The number of polymorphic bands ranged from three (OPG-10 and OPQ-04) to eight (OPR-16), with an average of five. A cluster analysis performed with the unweighted pair group method using arithmetic averages produced genetic similarity values among the blueberry cultivars ranging from 0.53 to 0.85, with an average similarity of 0.68. A dendrogram clustered the 45 blueberry cultivars into two main clusters, with a similarity value of 0.65. Cluster I consisted of four rabbiteye cultivars (Pink Lemonade, Alapaha, Titan, and Vernon) and the Ashworth northern highbush cultivar. Cluster II consisted of 31 northern highbush cultivars, eight southern highbush blueberry cultivars, and Northland half-highbush blueberry cultivar. Fifty five RAPD fragments selected were sequenced to develop sequence-characterized amplified region (SCAR) markers, resulting in the successful conversion of 16 of 55 fragments into SCAR markers. An amplified polymorphic band has the same size as the RAPD fragment or smaller according to the primer combinations in the 16 SCAR markers. Among these markers, a combination of 11 SCAR markers provided sufficient polymorphisms to distinguish the blueberry cultivars investigated in this study. These newly developed markers could be a fast and reliable tool to identify blueberry cultivars.