scholarly journals 335 ORGANIZATION OF ARTICHOKE, CYNARA SCOLYMUS L., BASED ON RAPD MOLECULAR MARKER BANDING PATTERNS

HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 478e-478
Author(s):  
Jan G. Tivang ◽  
Neal DeVos ◽  
James Nienhuis ◽  
Paul Skroch

Individual heads (capitula) from five discrete artichoke, Cyara scolymus L., populations were evaluated using RAPD markers. One vegetatively-propagated cultivar; Green Globe; two seed-propagated cultivars, Imperial Star and Big Heart XR-1; and two breeding populations were examined. Twenty-seven RAPD primers were scored yielding 2 to 16 polymorphic bands resulting in a total of 178 bands. Our objective was to determine if RAPD markers could be used to distinguish between and within populations. The genetic relationships among populations as well as among individuals within each population were estimated using the ratio of discordant to total bands scored. Data reduction (MDS) provided a plot indicating five clusters corresponding to the five populations. Confirmation of the presence of five discrete clusters was obtained by analysis of variance of the marker frequencies. The genetic diversity index (GDI) was calculated for each populations as the pooled variance of band frequency for each population. The GDI values were highly correlated to the mean genetic distance within each population. The homogeneity of variance for the GDI values associated with each population were compared using the Siegel-Tukey test for homogeneity of spread.

Biologia ◽  
2011 ◽  
Vol 66 (2) ◽  
Author(s):  
Sanghamitra Samantaray ◽  
Tarun Patel ◽  
K. Geetha ◽  
Satyabrata Maiti

AbstractConservation of identified germplasm is an important component for efficient and effective management of plant genetic resources. Since Chlorophytum species are important medicinal plants, studies were carried out for identification and establish genetic relationships in three species of Chlorophytum and two high yielding genotypes of Chlorophtum borivilianum using RAPD markers. Out of one hundred primers tested, 47 decamers amplified a total of 454 distinct bands ranging from 0.25–3.0 kbp to identify and to evaluate genetic relationships between and among three species of Chlorophytum and two genotypes of Chlorophtum borivilianum. The cluster analysis indicated that three species of Chlorophytum and two genotypes (NRCCB-1 and NRCCB-2) of C. borivilianum formed two major clusters. The first major cluster constituted C. arundinaceum and C. tuberosum, and the second major cluster composed of two subclusters; the first subcluster represented NRCB-1 and NRCB-2 where as the second subcluster represented C. borivilianum. Thus, the RAPD markers have the potential for identification and characterization of genetic relatedness among the species and genotypes. C. borivilianum along with two genotypes also showed similar banding patterns which could be chosen as candidate markers for differentiating the other two species such as C. arundinaceum and C. tuberosum. This would helpful for breeding programmes and provides an important input in conservation biology.


2007 ◽  
Vol 55 (3) ◽  
pp. 375-382 ◽  
Author(s):  
S. Mamo ◽  
A. Ayana ◽  
T. Tesso

A study on the extent and pattern of genetic variability in late-maturing sorghum [ Sorghum bicolor (L.) Moench] landraces collected from the Wello and Hararge areas of Ethiopia was conducted using random amplified polymorphic DNA (RAPD) markers for 70 individuals representing 14 populations. Four oligonucleotide primers generated a total of 55 polymorphic bands with 13–19 bands per primer and a mean of 16 bands across the 70 individuals. The value of the Shannon diversity index among the populations (0.26) and between the two regions (0.24) was low to moderate, despite the high degree of polymorphic bands per primer. The mean genetic distance (0.25) between the populations was found to be low. The low genetic variation may be due to the reduced population size of late-maturing sorghum landraces in the two regions of Ethiopia because of farmers’ decisions in the process of planting, managing, harvesting and processing their crops. Partitioning of the genetic variation into variation between and within the population revealed that 92.9% and 7.10% of the variation was found to be between and within the populations, respectively. Cluster analysis of genetic distance estimates further confirmed a low level of differentiation in late-maturing sorghum populations both between and within the regions. The implications of the results for genetic conservation purposes are discussed.


1996 ◽  
Vol 121 (5) ◽  
pp. 783-788 ◽  
Author(s):  
Jan Tivang ◽  
Paul W. Skroch ◽  
James Nienhuis ◽  
Neal De Vos

The magnitude of genetic differences among and heterogeneity within globe artichoke cultivars is unknown. Variation among individual heads (capitula) from three artichoke cultivars and two breeding populations were evaluated using RAPD markers. One vegetatively propagated cultivar (`Green Globe'), two seed-propagated cultivars (`Imperial Star' and `Big Heart') and two breeding populations were examined. Two to thirteen polymorphic bands were observed for 27 RAPD primers, which resulted in 178 scored bands. Variation was found within and among all cultivars, and breeding populations indicating that all five groups represent heterogeneous populations with respect to RAPD markers. The genetic relationships among individual genotypes were estimated using the ratio of discordant bands to total bands scored. Multidimensional scaling of the relationship matrix showed five independent clusters corresponding to the three cultivars and two breeding populations. The integrity of the five clusters was confirmed using pooled chi-squares for fragment homogeneity. Average gene diversity (Hs) was calculated for each population sample, and a one-way analysis of variance showed significant differences among populations. `Big Heart' had an Hs value equivalent to the two breeding populations, while clonally propagated `Green Globe' and seed propagated `Imperial Star' had the lowest Hs values. The RAPD heterogeneity observed within clonally propagated `Green Globe' is consistent with phenotypic variability observed for this cultivar. Overall, the results demonstrate the utility of the RAPD technique for evaluating genetic relationships and contrasting levels of genetic diversity among populations of artichoke genotypes.


HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 573g-574
Author(s):  
Paul Skroch ◽  
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.


Encuentro ◽  
2016 ◽  
pp. 28-39
Author(s):  
Arlen Tijerino ◽  
Lourdes Callejas ◽  
David A. Cerda-Granados

The goal of this study was to assess the genetic diversity of Nicaraguan populations of Cedrela odorata using Random Amplified Polymorphic DNA (RAPD) markers. Thus, genomic DNA was isolated from leaf samples collected from ninety-two trees belonging to five Nicaraguan natural populations of C. odorata. The mean number of alleles per locus, effective number of alleles per locus, percentage of polymorphic loci, genetic diversity (He ) of Nei and diversity index (Ho ) of Shannon were estimated for each population assuming that the populations were in HardyWeinberg equilibrium. Total genetic diversity was partitioned in intrapopulational and interpopulational diversity using Nei’s genetic differentiation (GST) and through an Analysis of Molecular Variance (AMOVA). The ΦST matrix was used to construct a dendrogram by the neighbor-joining method. According to values of both He and Ho , Esquipulas (Deparment of Matagalpa) presented the lowest diversity level; while La Trinidad (Department of Estelí) showed the highest diversity level. Genetic differentiation was calculated obtaining a GST value of 13.36%. AMOVA also showed a similar differentiation value ΦST =13.81%). Neighbour-joining dendrogram clustered the five populations in two groups, where the group formed by La Trinidad and El Refugio (Department of Granada) presented the biggest differentiation. Correlation between genetic and geographical distances was not found.


Genetika ◽  
2014 ◽  
Vol 46 (3) ◽  
pp. 839-854 ◽  
Author(s):  
Vesna Peric ◽  
Ana Nikolic ◽  
Vojka Babic ◽  
Aleksanda Sudaric ◽  
Mirjana Srebric ◽  
...  

Modern agriculture, breeding procedures, as well as competition among breeding institutions contribute to further reduction of already narrowed diversity of soybean commercial varieties. The objective of the study was to characterize eighteen soybean cultivars from three different breeding programs for agro-morphological traits and to reveal genetic diversity using molecular markers. Morphological description was performed with 13 qualitative and 9 quantitative traits. The genetic relationships were estimated using 21 RAPD markers. PIC was calculated for RAPD data, while the diversity of qualitative traits was described by Shannon genetic diversity index. Cluster analysis based on qualitative morphological characters showed clear separation of genotypes on the basis of their plant growth type. PC analysis performed for quantitative traits divided genotypes according to their maturity group. Grouping pattern based on molecular marker data was in agreement with pedigree of cultivars. A great similarity was found, primarily between the varieties under the same institution, and then among all examined varieties. Comparison of three methods in the assessment of diversity indicated that morphological markers might provide useful information in breeding process and allow classification by pedigree to some extent, but RAPD markers were found to be superior in assessing differences among genetically very similar genotypes.


1997 ◽  
Vol 122 (6) ◽  
pp. 740-747 ◽  
Author(s):  
M.M. Paz ◽  
R.E. Veilleux

RAPD analysis was conducted on in vitro plantlets of Solanum phureja Juz. & Buk. monoploids and diploid heterozygous pollinators. Among 60 decamer primers screened, 11 did not show polymorphism while some primers produced complex banding patterns or faint bands that were difficult to score. Genetic distance estimates were based on 151 polymorphic RAPD markers of 208 bands scored using 33 primers. Simple matching and Jaccard coefficients were calculated to estimate genetic similarity (GS). Genetic distance (GD=1-GS) among genotypes ranged from 0.0 to 0.664. Cluster analysis yielded groups of genotypes that were consistent with known genomic compositions or genetic relationships inferred from their pedigree. Field evaluation of 14 F1 families resulting from five S. phureja doubled monoploids (DMs) crossed to three heterozygous pollinators (IDs) revealed significant differences in total tuber number, total tuber yield, average tuber mass, and vigor. Total tuber yield per family ranged from 174 to 404 g per plant and was significantly lower than the control `Kennebec'. The general combining ability of DM BARD 13-14/202 was superior to other DM parents. Specific combining ability was observed in progeny of AD2-4/3s.8 H ID 4. Among male parents, ID 8 performed better than ID 4 or ID 5. Using simple matching, the largest parental genetic distance was always associated with the highest total tuber yield among progenies of DM parents. A similar trend was obtained using Jaccard coefficients. Based on our results, RAPD markers may facilitate the identification of diverse parents to maximize the expression of heterosis in S. phureja hybrids.


1996 ◽  
Vol 75 (05) ◽  
pp. 772-777 ◽  
Author(s):  
Sybille Albrecht ◽  
Matthias Kotzsch ◽  
Gabriele Siegert ◽  
Thomas Luther ◽  
Heinz Großmann ◽  
...  

SummaryThe plasma tissue factor (TF) concentration was correlated to factor VII concentration (FVIIag) and factor VII activity (FVIIc) in 498 healthy volunteers ranging in age from 17 to 64 years. Immunoassays using monoclonal antibodies (mAbs) were developed for the determination of TF and FVIIag in plasma. The mAbs and the test systems were characterized. The mean value of the TF concentration was 172 ± 135 pg/ml. TF showed no age- and gender-related differences. For the total population, FVIIc, determined by a clotting test, was 110 ± 15% and the factor VIlag was 0.77 ± 0.19 μg/ml. FVII activity was significantly increased with age, whereas the concentration demonstrated no correlation to age in this population. FVII concentration is highly correlated with the activity as measured by clotting assay using rabbit thromboplastin. The ratio between FVIIc and FVIIag was not age-dependent, but demonstrated a significant difference between men and women. Between TF and FVII we could not detect a correlation.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Manjot Kaur Grewal ◽  
Shruti Chandra ◽  
Alan Bird ◽  
Glen Jeffery ◽  
Sobha Sivaprasad

AbstractTo evaluate the effect of aging, intra- and intersession repeatability and regional scotopic sensitivities in healthy and age-related macular degeneration (AMD) eyes. Intra- and intersession agreement and effect of age was measured in healthy individuals. The mean sensitivity (MS) and pointwise retinal sensitivities (PWS) within the central 24° with 505 nm (cyan) and 625 nm (red) stimuli were evaluated in 50 individuals (11 healthy and 39 AMD eyes). The overall intra- and intersession had excellent reliability (intraclass correlation coefficient, ICC > 0.90) and tests were highly correlated (Spearman rs = 0.75–0.86). Eyes with subretinal drusenoid deposit (SDD) had reduced PWS centrally, particularly at inferior and nasal retinal locations compared with controls and intermediate AMD (iAMD) without SDD. There was no difference in MS or PWS at any retinal location between iAMD without SDD and healthy individuals nor between iAMD with SDD and non-foveal atrophic AMD groups. Eyes with SDD have reduced rod function compared to iAMD without SDD and healthy eyes, but similar to eyes with non-foveal atrophy. Our results highlight rod dysfunction is not directly correlated with drusen load and SDD location.


2016 ◽  
Vol 3 (2) ◽  
pp. 1 ◽  
Author(s):  
Lighton Dube

<p>This study analyzes the degree of crop diversification and factors associated with crop diversification among 479 smallholder farmers in Manicaland and Masvingo provinces of Zimbabwe. The Herfindahl index used to estimate diversification, while the Tobit model evaluated factors associated with crop diversification.  The mean crop diversity index is 0.54. On average households in Nyanga and Bikita are the most diversified with indices of 0.48 and 0.49 respectively. The most specialized households are in Mutasa and Chiredzi with indices of 0.62. An analysis by gender shows that male headed households are slightly more diversified than female headed households. The Tobit model indicates that gender of head of household, education, number of livestock units, access to irrigation, membership to a farmers group, access to markets, farming experience, farms on flat terrain, farmer to farm extension, routine extension, agro-ecological zone and household income are significant contributors to increasing crop diversification. In turn, crop specialization is significantly associated with off-farm employment, soil fertility, farmers who are happy with extension contacts per year, farmers trained using the farmer field school approach and farmers who receive NGO extension support.</p>


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