Varietal identification of cyclamen and petunia is important for flower seed production because these crops are marketed as hybrids and genetic purity determinations assure the purity of the seed lot and the success of hybridization. Random amplified polymorphic DNA (RAPD) banding patterns have been shown to be useful in identifying genotypes of various crops. This molecular biology technique was applied to five commercial cyclamen and six petunia hybrids. Using bulk seed/seedling samples, the varieties could be differentiated. However, when individual seeds of the cyclamen hybrid were tested, differing polymorphisms were observed. These variations were attributed to genetic variability in the inbred parents. We conclude that the genetic purity of cyclamen seeds can be improved and that the use of RAPDs can assist breeders of hybrid flowering crops in better monitoring seed quality.
Jianhua Zhang and Miller B. McDonald
Jaladet M.S. Jubrael, Sripada M. Udupa, and Michael Baum
Currently, the identification and characterization of date palm varieties rely on a small number of morphological traits, mainly of fruit, which are complex and greatly influenced by the environment. As a result, different varietal names may actually refer to the same variety while different varieties may have the same name. Therefore, new descriptors like molecular markers are required to identify, characterize, and estimate genetic diversity in this crop. Here we used amplified fragment length polymorphism (AFLP) markers to discriminate 18 Iraqi date palm varieties and to estimate the genetic relationship among the varieties. A total of 122 polymorphic AFLP loci were scored, with an average of 17.4 polymorphic loci per primer combination. The use of any one of the four combinations, P101(aacg)/M95(aaaa), P74(ggt)/M95(aaaa), P73(ggg)/M95(aaaa), or P100(aacc)/M95(aaaa), was sufficient to uniquely identify all the varieties. Jaccard's genetic similarity index ranged from 0.108 to 0.756, indicating moderate to diverse relationships. Estimation of average proportion of fixed recessive AFLP loci indicated that most of the loci in variety `Chipchab' were fixed, whereas most of the loci in `Jamal Al-Dean' could be heterozygous and in-between in other varieties. Unweighted pair group method with arithmatic mean (UPGMA) analysis ordered the date palm varieties first into two broad groups at 27% similarity levels. One group consisted of seven varieties and the second group consisted of the remaining 11 varieties of date palm. These results showed that the AFLP technique is an efficient method for varietal identification and estimating genetic relationships in date palm.
M. Dolores Loureiro, M. Carmen Martínez, Jean-Michel Boursiquot, and Patrice This
`Albariño' (Vitis vinifera L.) is an important grape cultivar in Spain, morphologically diverse but subject to much misnaming. The objectives of the present work were to correct some of the more common misnamings concerning `Albariño' and to evaluate the genetic variability within this cultivar by analyzing DNA polymorphisms using randomly amplified polymorphic DNA (RAPD) markers and microsatellite techniques. Several accessions of `Albariño' (16 accessions from Misión Biológica de Galicia, one accession from El Encin, one accession from Rancho de la Merced), related cultivars (`Alvarinho', `Caíño blanco', `Cainho branco', `Loureiro'), and cultivars presumably identical to misnomers (`Savagnin blanc' and `Gewürztraminer') were analyzed using 20 RAPD markers and six microsatellite loci. Both techniques revealed polymorphism among `Albariño', `Caíño blanco', `Albariño' from Rancho de la Merced and `Loureiro'. No polymorphism was detected among the 16 `Albariño' accessions from Galicia, the `Albariño' accession from El Encin and `Alvarinho', nor among the `Albariño' accession from Rancho de la Merced, `Savagnin blanc' and `Gewürztraminer', nor between `Caíño blanco' and `Cainho branco'. These results enabled us to clarify the main misnomers concerning these cultivars. The absence of polymorphism among the true `Albariño' accessions did not allow the detection of any clonal variation. The suitability of both techniques for defining the cultivar level for grapevine is discussed.
Patricia Sweeney, Robert Golembiewski, and Karl Danneberger
Random amplified polymorphic DNA (RAPD) markers from leaf tissue extractions are effective for discrimination of turfgrass varieties. The usefulness of RAPD markers for turfgrass variety identification can be enhanced by use of seed rather than leaf tissue for DNA extraction. To determine whether DNA extracted from turfgrass seed was suitable for amplification, DNA was extracted from bulk samples and individual seeds of bermudagrass [Cynodon dactylon (L.) Pers.], chewings fescue (Festuca rubra var. commutata Gaud.), Poa annua L., Poa supina Schrad., creeping bentgrass [Agrostis stolonifera L. var. palustrus (Huds.) Farw.], Kentucky bluegrass (Poa pratensis L.), perennial ryegrass (Lolium perenne L.), and tall fescue (Festuca arundinacea Schreb.). All samples were successfully amplified using an arbitrary primer. Amplification intensity varied among species. With an almost infinite number of arbitrary primers available, it is likely that suitable primers can be found to amplify DNA from most turfgrass species. Amplification of turfgrass seed DNA, whether bulk or individual seed, is possible and should prove more useful than amplification of leaf tissue DNA for discrimination of turfgrass varieties.
Tilin Fang, Yanqi Wu, Shiva Makaju, Todd Tribble, Dennis L. Martin, and Justin Q. Moss
. The 11 SSR primer pairs (PPs) used for varietal identification by Wang et al. (2010) and additional 35 SSR PPs [no. 12–46 ( Table 2 )] were selected based on the amplification efficiency and polymorphism from initial screening. PCR was conducted
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.
.S. transition zone, turf bermudagrasses have been increasingly used on sports fields; however, accurate varietal identification is challenging. Using simple sequence repeat DNA markers, Fang et al. (p. 714) reported that the favored bermudagrass on the
Carmen Soria, Juan J. Medina, Pedro Domínguez, María T. Ariza, Luis Miranda, Rosalía Villalba, Josefa Gálvez, José F. Sánchez-Sevilla, Iraida Amaya, Rafael Sesmero, and José M. López-Aranda
-Aranda, J.M. Valpuesta, V. Sánchez-Sevilla, J.F. 2006 EST-derived polymorphic microsatellites from cultivated strawberry ( Fragaria ×ananassa ) are useful for diversity studies and varietal identification among Fragaria species Mol
Imen Rekik, Amelia Salimonti, Naziha Grati Kamoun, Innocenzo Muzzalupo, Oliver Lepais, Sophie Gerber, Enzo Perri, and Ahmed Rebai
markers ( Grati Kamoun et al., 2006 ; Taamalli et al., 2006 ) and simple sequence repeat (SSR) markers ( Taamalli et al., 2006 , 2007 ). However, there is still a need for better genetic diversity assessment and varietal identification using high
Maria G. Emmanouilidou, Marios C. Kyriacou, and Isabel Trujillo
protocols for varietal identification. In this regard, a protocol recently has been established based on the integrated use of morphological and molecular markers (microsatellites) to facilitate the identification of the varieties present in olive gene banks