scholarly journals Genetic variability of Scots pine (Pinus sylvestris L.) in maternal regions of provenance

2015 ◽  
Vol 57 (2) ◽  
pp. 112-119 ◽  
Author(s):  
Paweł Przybylski ◽  
Jan Matras ◽  
Małgorzata Sułkowska

Abstract The analysis of chosen selected Scots Pine (Pinus sylvestris L.), populations representing different seed regions: 107 (Międzyzdroje), 305 (Woziwoda), 206 (Strzałowo), 208 (Białowieża), 504 (Bolesławiec), 606 (Józefów) were performed using 10 isoensyme markers: Gdh (E.C.1.4.1.2), Sdh-A, Sdh-B (E.C.1.1.1.25), Pgd-B (E.C.1.1.1.44), Mdh-A, Mdh-C (E.C.1.1.1.37), Got-A, Got-B, Got-C (E.C.2.6.1.1), Dia-C (E.C.1.8.1.4). There were calculated following genetic parameters: allelic frequencies, observed and expected heterozygosities, and Wright’s fixation indexes. In populations, the results of analysis indicated presence of rare alleles. In all study populations, the average effective number of alleles per locus was 1.46 and was lower than expected number of alleles per locus of 1.93. The results for the effective number of alleles of the population per locus were as follows: Strzałowo and Białowieża 1.54, Bolesławiec 1.48, Jozefów 1.44, Świnoujście 1.42, Woziwoda 1.35. Average observed heterozygosity in the studied populations was calculated at the level of 0.26 and it was lower than the expected heterozygosity at 0.28. For populations, the level of heterozygosities were as follow: Strzałowo 0.35, Bolesławiec and Białowieża 0.25, Józefów 0.27, Świnoujście 0.23, Woziwoda 0.26. In particular loci level of heterozygosity was different, as the most heterozygous Mdh-C locus was estimated, while minimum Got-C. Significant differences in allele frequency of Hardy-Weinberg deviation equilibrium were found in 10 cases: Strzałowo (Got-C), Bolesławiec (Got-B), Białowieża (Got-B, Gdh), Józefów (Mdh-C), Międzyzdroje (Got-B, Got-C, Mdh-C), Woziwoda (Got-C, Gdh). All studied populations had a lower effective number of alleles per locus (Ne) comparing to the observed number of alleles (Na). Wright’s fixation indices were negative for populations: Strzałowo (-0.09), Józefów (-0.03), Międzyzdroje (-0.01) and positive for: Białowieża (0.12), Woziwoda and Bolesławiec (0.07). The extremely high Wright’s fixation index (0.12) was observed for Białowieża population.

2007 ◽  
Vol 37 (2) ◽  
pp. 395-403 ◽  
Author(s):  
P. Belletti ◽  
I. Monteleone ◽  
D. Ferrazzini

Genetic diversity and differentiation of 12 native populations of sycamore ( Acer pseudoplatanus L.) from northwestern Italy were investigated by means of variation detected in 10 polymorphic isozyme systems encoded by 16 loci. The trees showed relatively large genetic variability (mean number of alleles per locus = 2.78, effective number of alleles per locus = 1.47, percentage of polymorphic loci = 96.9, expected heterozygosity = 0.280) but small interpopulational variation (FST = 0.019), suggesting the presence of a single gene pool. A slight excess of heterozygotes was found, and the overall inbreeding coefficient (FIS) was –0.038. There was a positive correlation between the age of the individuals sampled and heterozygosity, suggesting the occurrence of natural selection against homozygotes. No significant correlation was detected between genetic and geographic distances of populations, confirming the lack of any barriers to gene flow. Estimate of the mean effective number of migrants exchanged between populations was 4.399, based on the private alleles method. The contribution of the results in relation to terms of the most appropriate strategies to preserve genetic variability of sycamore and to collect forest reproductive material is discussed.


2015 ◽  
Vol 76 (3) ◽  
pp. 240-249
Author(s):  
Paweł Przybylski

Abstract Scots pine (Pinus sylvestris L.) is the most common species in Poland’s forest stands. The mode of pine stands renovation requires that silviculture practitioners have continuous access to seed banks. Orchard-grown seeds are predicted to constitute an increasingly larger part of the average demand for pine seeds in Poland. Seed orchards, due to a limited number of maternal trees as well as the irregularity of their blooming and pollination, enhance the risk of genetic diversity reduction in planted forest stands. This is of particular importance in the context of dynamic climate change. Markers based on microsatellite DNA fragments are effective tools for monitoring genetic variability. In the present study, three different microsatellite DNA fragments were used: SPAC 12.5, SPAG 7.14 and SPAC 11.4. The main objective of this research was to study genetic variability in one of the biggest seed orchards in Poland, located in the Forest District Susz. The obtained results indicated heterozygosity loss within the orchard, proving the existence of specimen selection effects on genetic variability. Hence, it seems quite important to take account of molecular genetic variability of maternal trees in future breeding strategies.


2020 ◽  
Vol 45 (1) ◽  
pp. 51-60
Author(s):  
A. Mohammed ◽  
A. O. Raji ◽  
J. U. Igwebuike

The genetic variability of some Nigerian breeds of sheep at the IGF 1 locus was investigate blood samples from 150 sheep (50 each of Yankasa, Balami and Uda sheep) were collected from the Maiduguri abbatoir and analysed at the Biotechnology centre of the University of Maiduguri. A relatively high level of genetic variability was detected in Nigerian sheep; the mean observed heterozygosity (Ho) and expected heterozygosity (He) values were 0.433 and 0.476, respectively. Comparison of expected heterozygosity of alleles between the populations showed that yankasa was the most heterozygous of the sheep populations though the unbiased expected heterozygosity (0.503) for the Yankasa was the same as that of the Balami. All populations were 100% polymorphic at the IGF 1 locus with fixation index ranging from -0.169 to 0.378 and a mean of 0.093, which suggests a general pattern of random mating. Similarly, low mean values for Fis (0.093), F (0.089), Fis (0.089), Fit (0.130) and Fst (0.045) supports the assertion that inbreeding was limited due to outcrossing with relatively high level of gene-flow (Nm = 5.292). The analysis of molecular variance (AMOVA) revealed that only 1% of the total variations observed in the sampled populations is accounted for by the population differences while individual differences accounted for 85%. The UPGMA phylogenetic tree revealed that the Uda and Yankasa populations are closer to each than each is to Balami. Thus, it can be concluded that sufficient genetic variation exist in the studied Nigerian sheep breeds and these populations are unlikely to decline due to inbreeding.  


2014 ◽  
Vol 75 (1) ◽  
pp. 47-54 ◽  
Author(s):  
Justyna Anna Nowakowska ◽  
Tadeusz Zachara ◽  
Agata Konecka

Abstract The genetic variability and biodiversity of tree populations ensure the stability and sustainability of forest ecosystems. New research tools based on molecular DNA markers enable precise characterisation of forest genetic resources, i.e. detection of different allele frequencies in mature trees and progeny populations. The paper describes the genetic structure of mature stands of Scots pine (Pinus sylvestris L.) in Oława Forest District and Norway spruce (Picea abies L. Karst.) in Jawor Forest District and stands of their respective progeny. In the Scots pine stand, there was a slight increase (0.6%) in heterozygosity level and a larger increase (4.9%) in the inbreeding coefficient of progeny trees. In the Norway spruce stand, despite a small reduction (0.9%) in heterozygosity, a similar increase (4.6%) in the inbreeding coefficient of progeny was revealed. In both stands, allele richness and the partition probability of basic clustering were high. Both pine and spruce adults and progeny trees were characterised by high levels of genetic similarity (96% and 79%, respectively). Gene flow between the mature and progeny populations was high (Nm > 1) for both Scots pine and Norway spruce. Conservation of the gene pool within forest tree stands requires an increase in the proportion of natural regeneration. To estimate the extent to which genes are transmitted between adult trees and their progeny, more studies are needed, especially taking into account the influence of silviculture measures, like selective tree cutting, on the genetic variability of the younger generation. These results confirm that the gene pool was conserved when transmitted between the stands studied, as well as highlight the usefulness of such a study for silvicultural purposes


2006 ◽  
Vol 55 (1-6) ◽  
pp. 84-92 ◽  
Author(s):  
Anders Fries ◽  
Tore Ericsson

Abstract Wood density was analysed and annual ring width was measured on increment cores from 1400 trees in a 30-year-old full-sib progeny test of Scots pine (Pinus sylvestris L.) in north Sweden. Genetic parameters for wood density were analysed separately for ten outer annual rings, and for simple averages of the five most recent years. The evaluation included genetic correlations with height and stem diameter. Heritabilities of density estimated separately for each annual ring was 0.14-0.26 without any age trend, and jointly for the ten or five latest rings 0.30-0.33; for height growth it was 0.30-0.42 and for stem diameter 0.11-0.13. Additive genetic correlations with height and stem diameter were negative with the simplest statistical model (ȓA = -0.425 and 0.511, respectively) but vanished or diminished when ring width was added as covariate. Density breeding values calculated for the parent trees for each of ten annual rings separately varied considerably between parent trees and between years, tending to increase with increasing age, with a substantial increase between the ages 14 to 16 years from the pith. This age fits well with literature data on the change from juvenile to mature wood. The genetic correlation for wood density between rings from different years was high: ȓA = 0.8 ten years apart, increasing to 1.0 for neighbouring rings. The high genetic correlations for wood density between the innermost and outermost annual rings indicate possible strong covariation between juvenile and/or transition wood and mature wood. The annual variation in wood density in relation to genetic regulation, phenology, environmental conditions, and development from juvenile to mature age is discussed.


2022 ◽  
Vol 52 (5) ◽  
Author(s):  
Joel Domínguez-Viveros ◽  
Antonio Reyes-Cerón ◽  
Juan Fernando Saiz-Pineda ◽  
Cesar Villegas-Gutiérrez ◽  
Guadalupe Nelson Aguilar-Palma ◽  
...  

ABSTRACT: This study analyzed the Sardo Negro breed pedigree (41,521 animals registered from 1958 to 2019) to determine its structure, evolution, and genetic variability (GV). The population genetic parameters evaluated were effective number of founders (fe) and ancestors (fa), pedigree integrity, additive genetic relationship (AGR); number of complete generations (NCG), maximum generations traced (NMGT), and equivalent complete generations (NECG); effective population size (Ne), inbreeding coefficient (F), and generation interval (GI). The average GI was 7.45 years. A total of 7,804 founders and 4,856 ancestors were identified for a fe of 185 and a fa of 97. The average and maximum values of NCG, NECG, and NMGT were 1.6 and 5.0, 2.5 and 6.5, 4.3 and 12, with Ne estimates of 15.9, 25.9, and 69.0, respectively. The increase in F, linked to Ne, ranged from 0.72% to 3.1% per generation. The average values for F and AGR were 3.6% and 1.0%, respectively. The proportion of inbred individuals was 32.0%, with F values ranging from 0.01 to 62.2% and an average of 11.3%. The rate of inbred population was 1.3% per year. The annual rate of AGR was 0.04%. For the continuity and projection of the breed, the evolution of F as a function of Ne and the possible implications of the selection schemes must be considered. The genetic variability sustained over time results from the Ne.


2014 ◽  
Vol 63 (3-4) ◽  
pp. 315-324 ◽  
Author(s):  
Jerzy Szweykowski ◽  
Wiesław Prus-Głowacki ◽  
Jerzy Hrynkiewicz

The comparison of the genetic stucture of the population of Scots pine from Szczeliniec Wielki Mt. with the population of its progeny and three other populations from the same geographic region shows great similarity of both populations as far as the frequencies of genes and genotypes are concerned. Also other genetic parameters, such as heterozygosity, genotypic polymorphism indices and a number of alleles per locus were in both populations very similar. It seems that our data proved that the provenance trial experiments reflect rather closely the genetic structure of maternal populations. The fact that the population from Szczeliniec Wielki and its "replica" are genetically most similar to the geographically closest population from Bystrzyca Kłodzka leads to the conclusion, that these populations are of common origin. Though the relic character of the population from Szczeliniec can not be excluded. The morphological distinctness of the population from Szczeliniec is caused by a modifying influence of environmental conditions.


2009 ◽  
Vol 128 (4) ◽  
pp. 377-386 ◽  
Author(s):  
Marta Scalfi ◽  
Andrea Piotti ◽  
Massimo Rossi ◽  
Paolo Piovani

2018 ◽  
Vol 61 (4) ◽  
pp. 469-473 ◽  
Author(s):  
Fariborz Asroush ◽  
Seyed-Ziaeddin Mirhoseini ◽  
Nejat Badbarin ◽  
Alireza Seidavi ◽  
Vincenzo Tufarelli ◽  
...  

Abstract. The use of molecular markers can support the management of endangered populations and should be combined with appropriate breeding strategies to improve productive traits avoiding the decline of the breed. The genetic variability at 10 microsatellite loci were investigated in a sample of 100 unrelated Markhoz goats (77 females and 23 males). The investigated population was reared at the Sanandaj Markhoz goat Performance Testing Station in Kurdistan, Iran. Markhoz goat, a multipurpose breed, is one of the most valuable genetic resources in Iran. All the studied loci were found to be polymorphic and a total number of 52 alleles were identified with an average number of alleles of 5.2. Moreover, some population genetic indices, such as observed and expected heterozygosity, observed and expected number of alleles, Shannon's index, Nei's expected heterozygosity, and polymorphism information content were also calculated. Despite the decreasing population size, Markhoz goat genetic diversity is still conserved. The breed seems to have a good level of genetic variability and, as a consequence, a potential margin of adaptability to environment and for future genetic improvement.


Sign in / Sign up

Export Citation Format

Share Document