bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic Variation of Anatolian Black Pine (Pinus nigra Arnold. subsp. pallasiana (Lamb.) Holmboe) in the Lakes District of Turkey
Authors: Gülcü S. , Üçler A. Ö. 
Published: October 2017

Abstract
In this study, morphological characteristics of juvenile 1- and 2-year-old seedlings of Anatolian black pine were studied to estimate the amount of genetic variation and heritability of seedling traits of the species in the Lakes District of Turkey. This nursery study involved 460 parent trees from 23 populations in a randomized complete block design. Traits studied were the number and length of cotyledons, hypocotyls and epicotyls lengths, weight and length of initial roots, height, root collar diameter, and stem and root fresh weights, and number of buds. Variation was higher among than within populations with individual tree heritability ranging from 0.09 to 0.76, whereas family mean heritability ranged from 0.16 to 0.80. Genetic and phenotypic correlations between juvenile and 1-year-old seedling traits were generally the same sign and magnitude. Variation and heritabilities were higher for growth-related traits than the number and length of embryonic tissues. The observed level of population differentiation was low, possibly due limited geographic sampling of populations, which spanned only 2° of latitudes and longitudes, and 300m in elevation. If the observed heritabilities for growth traits were sustained to tree maturity combined family and within family selection would be effective in improving growth of this species in the Lakes District of Turkey. A broader geographic sampling is recommended for better estimation of population differentiation and establishment of the geographic pattern of the species in this region.
Chromosomal Mapping of 18S-25S and 5S Ribosomal Genes on 15 Species of Fagaceae From Northern Thailand
Authors: Chokchaichamnankit P. , Anamthawat-Jónsson K. , Chulalaksananukul W. 
Published: October 2017

Abstract
Fifteen species of Fagaceae from Chiang Mai province, northern Thailand, were investigated: eight Castanopsis, four Lithocarpus and three Quercus species. The species were generally diploid with the chromosome number 2n = 24, and the basic number x =12 was confirmed in some species with meiosis. One tree belonging to Q. lenticellatus had 2n = 14. Chromosomal mapping of the highly repetitive 18S-25S and 5S ribosomal genes by fluorescence in situ hybridisation (FISH) was performed. Most species (from all three genera) showed four 18S-25S rDNA sites (two pairs: one subterminal major and one paracentromeric/intercalary minor loci) and two 5S rDNA sites (one pair: paracentromeric locus). Quercus kerrii also had two pairs of 18S-25S rDNA sites, but both were subterminal major loci. Two species, C. argentea and Q. brandisianus, only had one pair of 18S-25S rDNA sites. Two species, C. calathiformis and L. vestitus, showed an odd number of (unpaired) sites, and this indicated hybrid origin and/or polyploidy. Polyploid cells were detected in these species. The ribosomal gene maps based on both sequences together were genus-specific. In Castanopsis, the 18S-25S and the 5S genes were localized on three different chromosome pairs, and comprised species-specific maps. On the other hand, the ribosomal genes in Lithocarpus and Quercus were found only on two chromosome pairs, because one of the two 18S-25S rDNA loci was localized on the same chromosome as the 5S rDNA locus. The FISH markers may be used to clarify discrepancies arising from morphological assessments.
Triploid Induction in Populus alba x P. glandulosa by Chromosome Doubling of Female Gametes
Authors: Li Y. H. , Kang X. Y. , Wang S. D. , Zhang Z. H. , Chen H. W. 
Published: October 2017

Abstract
Efficient methods for obtaining unreduced female gametes are needed for triploid induction in Populus alba x P. glandulosa. A cytological study of MMCs and PMCs meiosis and staminate floral elongation revealed that there was a close association between MMCs meiotic stage and male bud phenology during development under the same environment conditions. Female buds of Populus alba x P. glandulosa were treated with 0.5% colchicine solution at the selected meiotic stages based on male bud phenology. The treated buds were pollinated with pollen of P. tomentosa. A high rate of unreduced female gametes occurred in late leptotene and pachytene stages of MMC, as evidenced by a relatively higher percentage of triploids in the progeny, when compared to progeny from colchincine application at other meiotic stages. The present results demonstrated that male bud phenology can be used to guide colchicine applications to female buds and cause a more efficient production of triploids.
Short Note: Development of Mitochondrial Markers for Population Genetics of Norway Spruce [Picea abies (L.) Karst.]
Authors: Maghuly F. , Burg K. , Pinsker W. , Nittinger F. , Praznik W. , Fluch S. 
Published: October 2017

AbstractNorway spruce is an important commercial tree species in northern and central Europe. Pure mitochondrial DNA isolated from tissue culture materials grown in the dark were used to construct a partial mitochondrial library. 100 clones were randomly selected and 19 markers were isolated. Three of these markers proved to be polymorphic and two showed maternal inheritance in controlled crosses. These markers will be useful for population genetic studies in P. abies.
Inheritance and Genetic Gain in Wood Stiffness in Radiata Pine Assessed Acoustically in Young Standing Trees
Authors: Matheson A. C. , Gapare W. J. , Ilic J. , Wu H. X. 
Published: October 2017

AbstractWood stiffness, measured in terms of its modulus of elasticity (MoE) is an important characteristic of radiata pine for structural products. To select high stiffness radiata pine for breeding purpose, rapid, inexpensive methods for measuring wood stiffness are desirable. In this study, we explored acoustic instruments to measure stiffness of young standing trees in radiata pine and examined inheritance and genetic gain for stiffness in an Australian national breeding program. Time of flight of sound waves was recorded in standing trees in two progeny trials, one in eastern Victoria (Flynn) aged 8 years and the other in South Australia (Kromelite) aged 7 years. Average time of flight at Kromelite was higher than at Flynn, (519 μs/metre compared to 463 μs/metre) which corresponds to 3.7 GPa and 4.7 GPa for MoE, respectively. Heritability for time of flight was higher at Flynn (h2= 0.67 ± 0.10) than at Kromelite (h2= 0.30 ± 0.14). Selection of the best 10% for time of flight based on pooled data would result in 21% genetic gain in wood stiffness.
Spontaneous Hybridization between Pinus sylvestris L. and P. mugo Turra in Slovakia
Authors: Kormutak A. , Demankova B. , Gömöry D. 
Published: October 2017

Abstract
Molecular evidence for spontaneous hybridization between Pinus sylvestris L. and P. mugo Turra in the putative hybrid swarm populations of the species in Slovakia was provided based on PCR-RFLP analysis of the cpDNA trnV-trnH region. Species-specific restriction profiles generated by Hinf I digests of the cpDNA products reliably identified P. sylvestris and P. mugo haplotypes of the embryos from open pollination. Simultaneous analysis of the respective cpDNA region in megagametophytes and embryos of individual seeds along with needles of a given maternal tree has enabled to score either the P. sylvestris or P. mugo haplotypes in the embryos illustrating hybridization patterns between the two species. Data obtained in this way indicate a relatively extensive hybridization which takes place between P. sylvestris and P. mugo. The extent of hybridization varied among populations as evidenced by the 41.1-58.7% proportion of hybrid embryos registered on the locality Habovka, and by the 8.3% and 2.7% proportions of hybrid embryos on the localities Tisovnica and Sucha Hora, respectively. The approach itself is recommended as a convenient method for monitoring the hybridization patterns in sympatric zones of the studied pine species.
Primer Note: A New Set of Highly Polymorphic Nuclear Microsatellite Markers for Nothofagus nervosa and Related South American Species
Authors: Marchelli P. , Caron H. , Azpilicueta M. M. , Gallo L. A. 
Published: October 2017

Abstract
Nothofagus is the main component of southern South American temperate forests. Overexploitation in the past has led to the loss of 40% of the original distribution range. Genetic diversity as well as biological processes shaping the distribution of the genetic variation (e.g. gene flow) constitutes basic knowledge for the implementation of conservation measures and for the definition of Evolutionary Significant Units. Nuclear microsatellites are the marker of choice for gene flow and fine-scale genetic structure studies. We enlarged a previous set of microsatellites (SSRs) for South American Nothofagus species, with special concern to Nothofagus nervosa (Phil.) Dim. et Mil. Five new SSRs are presented with allele numbers up to 12 in a single population. The primers transferred well to five related species (N. obliqua (Mirb.) Oerst, N. glauca (Phil.) Krasser, N. dombeyi (Mirb.) Oerst , N. pumilio (Poepp et Endl.) Krasser and N. antarctica (G. Forster) Oerst, with allele numbers up to 11. The high level of polymorphism promises a sufficient power for gene flow and parentage analyses.
Genetic Diversity and Population Structure of Apricot (Prunus armeniaca L.) from Northern Pakistan using Simple Sequence Repeats
Authors: Ali Khan M. , Maghuly F. , Borroto-Fernandez E. G. , Pedryc A. , Katinger H. , Laimer M. 
Published: October 2017

Abstract
A collection of 44 P. armeniaca accessions and three related species, from diverse geographic areas, covering the entire Northern hemisphere with emphasis on Pakistani apricots, was screened with 10 SSR primer pairs developed in apricot, to characterize the cultivars and establish their genetic relationship. Given the fact that the Central Asian region is considered a center of origin of apricot, particular attention was devoted to accessions from the Hunza region of Pakistan. The primers correctly amplified a repeatable polymorphic pattern, which unequivocally distinguished all genotypes under study. Altogether 123 alleles were identified with an average of 12.30 alleles per locus. The observed heterozygosity for individual loci ranged from 0.28 to 0.77 with an average of 0.64. A neighbour joining method identified four groups from: (A) Central Asia, (B) Irano-Caucasia, (C) Continental Europe and (D) North America. The dendrogram confirms the historic dissemination pathways of apricot from its centre of origin in Asia to the West. Apricot cultivars from the Hunza region (Northern Pakistan) revealed a high variability, as genetic diversity is still conserved due to the traditional practice of planting seeds from the best trees.
Genetic Variation in an International Provenance-Progeny Test of Pinus caribaea Mor. var. bahamensis Bar. et Gol., in São Paulo, Brazil
Authors: Sebbenn A. M. , Arantes F. C. , Boas O. V. , Freitas M. L. M. 
Published: October 2017

Abstract
A combined provenance-progeny test of Pinus caribaea var. bahamensis was established in Paraguaçu Paulista Experimental Station, São Paulo State, Brazil, in a “compact family” blocks design with 14 provenances, 2 to 10 families per provenance, 5 individuals per subplot, and 7 replications. Variation among and within island, provenances and families and genetic parameters for d.b.h., height, and real volume were investigated, about 15 years after planting. Analysis of variation for all studied traits revealed significant differences among islands, provenances within island and families within islands, suggesting the possibility of increasing the timber yield through selection of the more productive provenances and families within the best island. Genetic correlations on growth traits were high and statistically significant, indicating that substantial gains could be made through indirect selection for one trait based on direct selection for another. Norman Castle provenance from Abaco Island performed best for d.b.h. height and volume, while San Andros and Little Harbour Cay, both from Andros Island performed worst for d.b.h. and height, respectively, and South Riding from Grand Bahamas Island performed worst for volume. The best provenance growth compared to that P. elliottii var. elliottii species at the same experimental site suggests that P. caribaea var. bahamensis has high silvicultural potential for the Paraguaçu Paulista region.
Spatial Genetic Structure Within Two Contrasting Stands of Scots Pine (Pinus sylvestris L.)
Authors: Chybicki I. J. , Dzialuk A. , Trojankiewicz M. , Slawski M. , Burczyk J. 
Published: October 2017

AbstractWhen considering neutral nuclear markers, genetic differentiation of Scots pine (Pinus sylvestris L.) populations is known to be low. The homogeneity arises particularly as an effect of common ancestry in a recent evolutionary history as well as an extensive gene flow, especially through pollen. However, within populations several other forces may shape the spatial distribution of genetic variation, including establishment history, environmental and silvicultural selection. These local forces are known to produce non-random spatial patterns of genetic variation, however little is known on fine-scale spatial genetic structure of Scots pine. In this study, two stands of this species with different establishment histories, selected within one larger population located in northern Poland were genotyped and analysed for genetic variation and within-stand spatial genetic structure. Results revealed no differences in genetic variation, although stands are separated about 60 km, suggesting that the two populations share a common genetic pool. The spatial genetic structure in both stands was found to be slightly different and was attributed to differences in the mode of populations’ establishments. Finally, results confirmed that gene flow in Scots pine is extensive, causing genetic homogeneity within a single population.
A Strategy for the Second Breeding Cycle of Larix x marschlinsii in Québec, Canada Including Experiments to Guide Interspecific Tree Breeding Programme
Authors: Perron M. 
Published: October 2017

AbstractA strategy for the genetic improvement of Larix decidua P. Mill., L. kaempferi (Lamb.) Carrière and their hybrid (L. x marschlinsii Coaz) in Québec, Canada, was set up to provide short and long-term genetic gains, as well as basic populations for some fundamental experiments. A reciprocal recurrent selection with forward selection strategy (RRS-FS) will be applied by using a pollen mix breeding with a partial population paternity analysis (PMX/WPPA). The genetic mechanisms responsible for heterosis among trees remain poorly understood. This complicates the implementation of multi-species genetic improvement programmes seeking to achieve the full benefits of interspecific hybridization. Various strategies to exploit heterosis are outlined. To expand our knowledge and guide our future choices, basic research has been integrated directly into breeding and testing activities, as well as through experiments integrated within activities leading to recommendations about the top-ranked families to be used in reforestation (cuttings). These experiments can also serve as the basis for future studies seeking a better understanding of heterosis through molecular genetics.
Genetic Variation in Resistance Against Heterobasidion annosum (Fr.) Bref. in Picea abies (L.) Karst. Expressed After Inoculation of Neighboring Stumps
Authors: Wellendorf H. , Thomsen I. M. 
Published: October 2017

Abstract
Based on the well-established knowledge that important spread of H. annosum is performed through spore infection of stumps and subsequent spread of mycelium to neighboring trees at points of root contact, an inoculation experiment was established in three adjacent fully pedigreed 17-year old Norway spruce field trials. In June 1995, every third row was cut and stump-inoculated with conidia belonging to the two contrasting types, P and S. 5 years later the remaining trees were evaluated by clear-cutting and mapping of rot occurrence. 34% of the trees were attacked. For each host-tree, the most likely source of infestation (i.e. possible inoculated donor-stump 5 years earlier) was evaluated based on orientation of the rot on the stump surface supplemented with samples of re-isolation of H. annosum of the two types. According to these estimates, the tested S-type turned out to be more aggressive towards Norway spruce than the tested P-type. Genetic variation in resistance was most convincingly detected in the most informative trial F175B. The pattern of genetic variation in the two roles as donor and host seems to differ. However, genetic variation was also expressed as general resistance, which is defined as the combined effect of donor stump, living host and across the two tested types of H. annosum. No indication of host x pathogen interaction was detected. This evidence combined with the general experience that resistance against root rot pathogens usually is partial and based on the cumulative effects of several genes, suggests that sustainable genetic gains in relative resistance may be obtainable in breeding programs of Norway spruce. The developed experimental set-up represents a useful concept for screening existing genetic trials for field resistance within a time scale of 5-6 years.
Genetic Variation in Two Rare Endemic Mexican Trees, Magnolia sharpii and Magnolia schiedeana
Authors: Newton A. C. , Gow J. , Robertson A. , Williams-Linera G. , Ramírez-Marcial N. , González-Espinosa M. , Allnutt T. R. , Ennos R. 
Published: October 2017

AbstractPatterns of genetic variation were examined within two endemic tree species restricted to Mexican cloud forest, Magnolia sharpii and Magnolia schiedeana. Leaf samples collected from natural populations were analysed using PCR RFLP of cpDNA, Inter-SSR and isozyme genetic markers, which were used to test a series of hypotheses regarding patterns of intraspecific variation within the two species. Genetic diversity estimates derived from Inter-SSR markers (mean Spop of 0.56 and 0.50 for M. sharpii and M. schiedeana respectively) are comparable to values obtained for other tree species. As predicted on the basis of its larger geographic range, the degree of population differentiation was found to be higher within M. schiedeana than M. sharpii, with 12.9% and 3.4% of total variation recorded between populations for the two species respectively using isozymes, and 26% and 11% using Inter- SSR markers. Isozyme analyses indicated negative Fisvalues, which may be suggestive of inbreeding in populations of M. sharpii, but provided less evidence of inbreeding in M. schiedeana. On the basis of PCR RFLP analysis of cpDNA, two chloroplast types were differentiated, type A being recorded for all of the individuals of both species, with the exception of one population of M. schiedeana that was fixed for type B. These results are consistent with recent evidence suggesting that some endemic plant taxa are able to maintain relatively high diversity within populations despite the occurrence of inbreeding and genetic drift, and that species with wider geographic ranges tend to exhibit relatively high genetic differentiation among populations. Conservation strategies for these species need to take into account the significant genetic differences recorded among the populations studied.
What do we Lose with Online-Only Surveys? Estimating the Bias in Selected Political Variables Due to Online Mode Restriction
Authors: Pforr Klaus , Dannwolf Tanja 
Published: October 2017

Abstract
This paper adds to the discussion on the value of online surveys for political science research. Mainly because of the lower costs, collecting survey data over the web has become increasingly popular in recent years, despite the higher sampling and coverage error in web-only surveys, especially online access polls. Recruiting respondents for the actual panel surveys based on a representative sample using a different mode is regarded as a solution to the sampling problem. Two approaches have been used to tackle the problem of coverage error: Providing respondents with computers (e.g. LISS, ELIPPS, GIP) and offering a different mode than online to respondents, thereby adopting a mixed mode design (e.g. paper as in GALLUP, GESIS Panel). The literature suggests that offering participation in the respondent’s preferred mode affects response rates positively but not much is known about respondents’ reasoning to choose a specific mode. We argue that it is important to understand this decision to evaluate the selection into online surveys and the consequences this has for data quality. We investigate this question by drawing on data from the GESIS Panel face-to-face recruitment interview for building a mixed mode access panel (paper and web) in Germany that gave a mode choice to internet users. Our results suggest that web literacy, age and education alone do not explain the mode choice but that affinity towards the technology related to the online mode has an independent effect. In a second step, we analyse the effect of this selection mechanism on answers to questions on typical variables used in political participation research such as media competence, political interest and civic duty in the subsequent mixed mode survey. We assess the added value of adopting a mixed-mode strategy. The results inform the evaluation of biases in unimode online surveys.
Purification and characterization of Rhizoctonia solani AG-4 strain ZB-34 α-amylase produced by solid-state fermentation using corn bran
Authors: Uzun Umit , Demirci Erkol , Yildirim Akatin Melike 
Published: October 2017

Abstract

Background
Aim of the study was to produce α-amylase cheaply from Rhizoctonia solani AG-4 strain ZB-34 by solid-state fermentation and investigate its suitability for some industries.

Methods

Rhizoctonia solani AG-4 strain ZB-34 α-amylase was purified with starch affinity method.

Results
The best production of enzyme was achieved by using corn bran. Optimum pH and temperature were 5.5 and 50°C, respectively. V
max and K
0.5 were determined as 238.8 U/mg protein and 0.03% from substrate-activity curve. Activity was maintained about 100% in the tested pHs after 1 day incubation. The enzyme conserved full of its activity at 4 and 28°C for 120 min. Mn2+, Ca2+, Tween 20, Triton X-100 and Triton X-114 activated the enzyme. The enzyme was highly active in the presence of some commercial detergents. The chocolate stains on the cotton fabrics were more effectively cleaned with the combination of a commercial detergent and purified enzyme. The purified enzyme also clarified the raw apple juice and desized the cotton fabrics.

Conclusion
The results showed that Rhizoctonia solani AG-4 strain ZB-34 α-amylase might have potential application as a detergent additive. In addition, its activity between pH 4.0 and 7.0 may facilitate its use in the food and fruit processing industries.