visualized using MEGA version 4 ( Tamura et al., 2007 ). The correlation of genetic distances based on total markers or panels was assessed using Mantel test in PowerMarker. Discriminatory power of markers. Twenty-five genic SSRs were employed for WHICHLOCI
Xiaobai Li, Weirui Li, Chenlu Di, Ming Xie, Liang Jin, Cheng Huang and Dianxing Wu
Zhi-li Suo, Wen-ying Li, Juan Yao, Hui-jin Zhang, Zhi-ming Zhang and Di-xuan Zhao
Tree peony cultivars are usually classified according to flower characteristics (flower form and flower color) which are commonly affected by environmental influences and developmental levels. Judgment of flower forms may also depend on the observer. Precise and rapid cultivar identification methods are also required to manage cultivar collections as well as tree peony breeding programs. The objective of this paper is to analyze the discriminatory ability of leaf morphology and Intersimple sequence repeat (ISSR) marker systems for tree peony cultivars. As a result, although there exist large variations of leaf morphology of tree peony cultivars, the morphological characteristics of biternately compound leaves 3, 4, and 5 from the base of a shoot at the middle part of a plant are relatively stable with smaller variations within cultivars (2.7% to 27.1%, 16.8% on average) and with larger differentiations among cultivars (72.9% to 97.3%, 83.2% on average). Statistical and principal components analyses indicate that 12 leaf morphological characteristics are valuable for cultivar classification. ISSR markers present a precisely discriminatory power in tree peony cultivar classification without environmental influences. The cultivars with multiple flower forms, which makes it difficult to make judgment by means of a flower-form-based classification system, have been significantly characterized using leaf morphology or ISSR markers.
Ettore Barone, Luigi Di Marco, Francesco P. Marra and Maria Sidari
Canonical discriminant analysis (CDA) of morphometric data of buds, leaves, and fruit, as well as isozyme analysis (esterase, peroxydase, and acid phosphatase) of leaf samples, were used to identify eight male pistachio selections and 10 female pistachio cultivars. According to the CDA, 77% and 93% of the total variance was summarized by the first three canonical discriminant functions for the female and male selections, respectively. Fruit characteristics, particularly fruit fresh and dry weights and fruit length, accounted for most of the discriminatory power for the female cultivars, while the dimensions of the leaves, principally leaf rachis length, were the most effective discriminating characters for the males. Isozyme analysis showed a higher degree of polymorphism in the male than the female genetic pool. Hence, using only three enzymes, it was possible to identify all of the male selections, but only 50% of the females. Peroxidase polymorphism clearly demonstrated the greater phylogenetic distance between `Kerman' and the local cultivars, as well as between `Cerasola', a quite different cultivar with a reddish hull, and the others tested. The combination of CDA and isozyme analysis enhanced the possibility of uniquely identifying the female cultivars.
Mario I. Buteler, Don LaBonte and Raul Macchiavelli
The breeding of new sweetpotato varieties is a highly inefficient process, confounded by incompatibility, poor fertility, open-pollination, and its hexaploid nature. Upwards of 12 to 20 lines are currently combined in open-pollinated nurseries based on good horticultural characteristics. Most progeny after several years of selection can be traced back to just three or four maternal lines. A method that would identify the paternal parent of superior progeny would enable breeders the ability to combine parents that exhibit superior combining ability in more-efficient, smaller nurseries. The objective of this work is to explore by means of computer simulation the application of genealogy reconstruction techniques on hexaploid individuals with PCR-based data. The progeny obtained on each female parent is fractionally assigned to each male with non zero exclusion probability proportional to its paternity likelihood. Computer simulations show that at least five different alleles per loci are needed to reach a reasonable discriminatory level. Also, the number of loci scored should not be less than 20. An increment in the number of alleles or loci increases the discriminatory power; but, the number of alleles produces a far more important effect than the number of loci.
Mehmet Nuri Nas, Nedim Mutlu and Paul E. Read
RAPD and phenotypic analysis were conducted to assess clonal stability of hazelnuts generated from axillary buds cultured in vitro for long-term. The nuts produced on in vitro-propagated plants were indistinguishable from those of donor plants. With the exception of rare horizontal (plagiotropic) growth, all in vitro-propagated plants exhibited phenotypes similar to those of donor plants. RAPD analysis did not reveal any somaclonal variation between donor plants from which in vitro cultures were initiated and micropropagated plants (6-year cultures), and no somaclonal variation was detected among in vitro-propagated plants. However, polymorphism (15.6%) was detected between the parent plant and its in vitro-propagated progenies (from seedlings). These results show a good discriminatory power of RAPD to detect polymorphism between samples where it is expected, and it can be effectively used for genetic assessment of micropropagated hazelnut. No evidence of genetic or epigenetic changes was observed in long-term cultured hazelnut, and thus long-term in vitro culture of hazelnut does not seem to limit its clonal propagation.
Ambika B. Gaikwad, Tusar Kanti Behera, Anand K. Singh, Devanshi Chandel, Jawahir L. Karihaloo and Jack E. Staub
, however, could not give complete insight into the cultigens examined. The discriminatory power of amplified fragment length polymorphism (AFLP) is often found to be greater than that of RAPD and ISSR markers ( Powell et al., 1996 ; Vos et al., 1995 ) as a
Jacob Mashilo, Hussein Shimelis, Alfred Odindo and Beyene Amelework
reported the discriminatory power of these markers. Xu et al. (2011) also used SSR markers to determine the genetic diversity of bottle gourd genotypes from China. Bottle gourd is an under-researched genetic resource in South Africa ( van Rensburg et al
Li-Chun Huang and Tzu-Fang Yeh
measure of the discriminatory power of an independent variable across all the discriminant functions when more than one discriminant function is estimated. Relatively speaking, the greater the potency index, the stronger the discriminatory power with which
Jennifer A. Kimball, M. Carolina Zuleta, Matthew C. Martin, Kevin E. Kenworthy, Ambika Chandra and Susana R. Milla-Lewis
including: total number of bands, number of polymorphic bands, and the percentage of polymorphic bands. The discriminatory power of each PC was assessed by calculating the polymorphic information content (PIC) and marker index (MI) values. The mean PIC value
Briana L. Gross, Gayle M. Volk, Christopher M. Richards, Philip L. Forsline, Gennaro Fazio and C. Thomas Chao
differences resulting from instrumentation. Probability measurements and identification of “duplicates.” Basic diversity statistics, along with polymorphism information content and discriminatory power for each locus in the nine SSR data set, were calculated