scholarly journals Genetic Diversity of Seed Orchard Crops

10.5772/33802 ◽  
2012 ◽  
Author(s):  
Murat Ertekin
Keyword(s):  
Genetic Diversity ◽  
Seed Orchard

scholarly journals Comparison of Genetic Diversity in Naturally Regenerated Norway Spruce Stands and Seed Orchard Progeny Trials

Forests ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 926 ◽  
Author(s):  
Dainis Ruņģis ◽  
Solveiga Luguza ◽  
Endijs Bāders ◽  
Vilnis Šķipars ◽  
Āris Jansons
Keyword(s):  
Genetic Diversity ◽  
Norway Spruce ◽  
Gene Diversity ◽  
Seed Orchard ◽  
Seed Orchards ◽  
Spruce Stands ◽  
Ssr Loci ◽  
Naturally Regenerated Stands ◽  
Average Gene ◽  
Environmental Events

Forest ecosystems in Europe are expected to experience changes in temperature and water regimes associated with increased risks of extreme environmental events and disasters. Genetic diversity and relatedness has been linked to resilience of forest stands and landscapes. Genetic diversity indicators were compared between a Norway spruce population naturally regenerated after extensive windthrow and Norway spruce progeny populations derived from two seed orchards. In addition, genetic diversity in an undisturbed stand in a long established national park and a spruce genetic resource stand were analyzed. Populations were genotyped at 11 simple sequence repeat (SSR) loci. Average genetic diversity indicators were similar across populations. However, the total number of alleles, average number of alleles over all loci, effective number of alleles, average gene diversity, and average allelic richness were highest in the naturally regenerated population and lowest in one of the seed orchard progeny populations. The genetic diversity in progeny from seed orchards used for stand renewal is comparable to the genetic diversity in naturally regenerated stands. However, fluctuations in seed production between years can have a large impact on genetic diversity in seed orchard progeny. The use of improved Norway spruce germplasm deployed via clonal seed orchards for forest renewal can maintain similar levels of genetic diversity compared to naturally regenerated stands, while also increasing production and timber quality.

scholarly journals Fertility Variation and Genetic Diversity in a Clonal Seed Orchard of Cryptomeria japonica

2005 ◽  
Vol 54 (1-6) ◽  
pp. 104-107 ◽  
Author(s):  
K. S. Kang ◽  
Y. A. El-Kassaby ◽  
M. S. Chung ◽  
C. S. Kim ◽  
Y. J. Kang ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Cryptomeria Japonica ◽  
Seed Orchard ◽  
Clonal Seed Orchard ◽  
Fertility Variation ◽  
The Status ◽  
Status Number ◽  
Census Number ◽  
Male Strobilus ◽  
Male Strobili

Abstract Clonal differences in fertility (expressed as the number of female and male strobili) were determined for three consecutive years (2002-2004) in a clonal seed orchard of sugi (Cryptomeria japonica D. Don) in Korea. Fertility varied among clones and among years producing three-year averages of 196 and 652 for female and male strobili per ramet, respectively. Correlation between female and male strobilus production was positive over the three years and statistically significant in 2003, a good flowering year. Based on the observed fertility variation, the status numbers (Ns, measure of genetic diversity) were calculated and varied from 25.6 to 31.7 among the three studied years. On average (pooled), relative status number was 86% of the census number (N). Variation in female fertility was higher than that in male fertility, and this variation was reflected on female and male parents’ status numbers. Pooled Ns estimated from the three years was higher than that for any single year, implying that genetic diversity would increase when seeds collected from different years are pooled.

scholarly journals Genetic diversity of seeds from four German Douglas fir (Pseudotsuga menziesii) seed orchards

2021 ◽  
Author(s):  
Birte Pakull ◽  
Pascal Eusemann ◽  
Janine Wojacki ◽  
Diana Ahnert ◽  
Heike Liesebach
Keyword(s):  
Genetic Diversity ◽  
Pseudotsuga Menziesii ◽  
Seed Orchard ◽  
Small Population ◽  
Douglas Fir ◽  
Next Generation ◽  
Seed Orchards ◽  
Population Sizes ◽  
Spatial Isolation ◽  
Offspring Generation

AbstractIn Germany, Douglas fir (Pseudotsuga menziesii Franco) is seen as a valuable species for future cultivation in times of climate change. Local seed production in seed stands and seed orchards may secure that local adaptation is transferred to the next generation, but small population sizes could lower genetic diversity and thus future adaptability. Here we analyse the transfer of genetic diversity from parent to offspring generation in four older German seed orchards. We detected low pollen contamination rates due to high levels of spatial isolation. Even with a relatively low number of 40 clones, seed orchard design with randomized and repeated planting of clones led to low selfing rates, and despite uneven parental contributions, the number of successful parents and the level of genetic intermixture were high enough to allow the transfer of an adequate part of the genetic diversity to the next generation. Larger numbers, however, might be needed to reliably conserve the entire genetic diversity over succeeding generations. Conclusions on the establishment of future seed orchards and regarding areas requiring further research are drawn at the end of the paper.

Comparisons of genetic diversity in white spruce (Picea glauca) and jack pine (Pinus banksiana) seed orchards with natural populations

2001 ◽  
Vol 31 (6) ◽  
pp. 943-949 ◽  
Author(s):  
M J.W Godt ◽  
J L Hamrick ◽  
M A Edwards-Burke ◽  
J H Williams
Keyword(s):  
Genetic Diversity ◽  
Picea Glauca ◽  
Pinus Banksiana ◽  
Gene Diversity ◽  
Natural Populations ◽  
Source Area ◽  
White Spruce ◽  
Seed Orchard ◽  
Jack Pine ◽  
Seed Orchards

Genetic diversity within a white spruce (Picea glauca (Moench) Voss) seed orchard (consisting of 40 clones) and a jack pine (Pinus banksiana Lamb.) seed orchard (31 clones) was assessed and compared with genetic diversity in natural populations within the source area for the orchards. Genetic diversity was determined at 18 allozyme loci for seven white spruce populations and 27 loci for five jack pine populations, and the two orchards. Gene diversity maintained within the seed orchards (He = 0.157 for white spruce and 0.114 for jack pine) was similar to that found within the source area for each species (He = 0.164 and 0.114 for white spruce and jack pine, respectively). However, nine white spruce alleles and 12 jack pine alleles identified in the source area were not present in the seed orchards. These alleles occurred at low frequencies in the natural populations (mean frequency = 0.023 and 0.014 for white spruce and jack pine, respectively). Mean genetic identities between the seed orchards and their natural populations were high (>0.99), indicating that common allele occurrences and frequencies were similar between the orchards and their source area. One allele in the white spruce orchard and two in the jack pine seed orchard did not occur within the natural population samples. Simulations indicated that randomly reducing the number of clones within the seed orchards would decrease allelic richness slightly but would have little effect on overall gene diversity.

scholarly journals SNP-based analysis reveals unexpected features of genetic diversity, parental contributions and pollen contamination in a white spruce breeding program

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Esteban Galeano ◽  
Jean Bousquet ◽  
Barb R. Thomas
Keyword(s):  
Genetic Diversity ◽  
Population Size ◽  
Effective Population Size ◽  
White Spruce ◽  
Seed Orchard ◽  
Pedigree Reconstruction ◽  
Effective Population ◽  
Pollen Contamination ◽  
Contamination Levels ◽  
The Impact

AbstractAccurate monitoring of genetic diversity levels of seedlots and mating patterns of parents from seed orchards are crucial to ensure that tree breeding programs are long-lasting and will deliver anticipated genetic gains. We used SNP genotyping to characterize founder trees, five bulk seed orchard seedlots, and trees from progeny trials to assess pollen contamination and the impact of severe roguing on genetic diversity and parental contributions in a first-generation open-pollinated white spruce clonal seed orchard. After severe roguing (eliminating 65% of the seed orchard trees), we found a slight reduction in the Shannon Index and a slightly negative inbreeding coefficient, but a sharp decrease in effective population size (eightfold) concomitant with sharp increase in coancestry (eightfold). Pedigree reconstruction showed unequal parental contributions across years with pollen contamination levels between 12 and 51% (average 27%) among seedlots, and 7–68% (average 30%) among individual genotypes within a seedlot. These contamination levels were not correlated with estimates obtained using pollen flight traps. Levels of pollen contamination also showed a Pearson’s correlation of 0.92 with wind direction, likely from a pollen source 1 km away from the orchard under study. The achievement of 5% genetic gain in height at rotation through eliminating two-thirds of the orchard thus generated a loss in genetic diversity as determined by the reduction in effective population size. The use of genomic profiles revealed the considerable impact of roguing on genetic diversity, and pedigree reconstruction of full-sib families showed the unanticipated impact of pollen contamination from a previously unconsidered source.

scholarly journals High Levels of Outcrossing in a Family Trial of Western Australian Sandalwood (Santalum spicatum)

2007 ◽  
Vol 56 (1-6) ◽  
pp. 222-230 ◽  
Author(s):  
K. Muir ◽  
M. Byrne ◽  
E. Barbour ◽  
M. C. Cox ◽  
J. E. D. Fox
Keyword(s):  
Genetic Diversity ◽  
Mating System ◽  
Natural Populations ◽  
Seed Orchard ◽  
Seed Crop ◽  
The Mean ◽  
Santalum Spicatum ◽  
High Level ◽  
Western Australian ◽  
Seed Collections

Abstract The mating system of Western Australian sandalwood (Santalum spicatum) was investigated in seed collections from a family trial. The mean outcrossing rate was high (95.2%) although there was variation among families and one family showed particularly low outcrossing, high bi-parental inbreeding and high correlated paternity. Variation in flowering time between this family and others in the trial was the most likely cause of the high inbreeding and low number of fathers contributing to the seed crop in trees from this family. The high level of outcrossing in the rest of the families indicated that S. spicatum has a preferentially outcrossed mating system, but that it is capable of selfing when conditions are unsuitable for outcrossing. The seedling progeny showed no influence of inbreeding on seedling height at 4 months. Analysis of genetic diversity revealed high levels of genetic diversity have been captured in the seed crop from the trial, and this diversity is comparable to that identified in a previous study of natural populations from throughout the range of the species. These results indicated that production of seed through seed orchards will be a successful means of deployment of breeding gains in the species, however it is essential to ensure overlap in flowering times among different families planted in a seed orchard.

scholarly journals Clone Fertility and Genetic Diversity in a Black Pine Seed Orchard

2010 ◽  
Vol 59 (1-6) ◽  
pp. 145-150 ◽  
Author(s):  
M. Ertekin
Keyword(s):  
Genetic Diversity ◽  
Male Fertility ◽  
Seed Orchard ◽  
Clonal Variation ◽  
Black Pine ◽  
Fertility Variation ◽  
The Status ◽  
Status Number ◽  
Census Number ◽  
Male Strobili

AbstractClonal variation in the number of female and male strobili was studied for three consecutive years (2002-2004) in a clonal black pine seed orchard in Turkey. The data showed large differences in female and male fertility among clones in the three years. The correlation between female and male strobilus production was negative and statistically significant in 2004, a good-flowering year. Clonal fertility and fertility variation, expressed by the sibling coefficient and coefficient of variation in strobilus production among 30 clones, were reported. Fertility varied among clones and among years, producing three-year averages of 99.3 and 801.6 for female and male strobili per ramet, respectively. Male fertility variation was higher than was female fertility variation in the three years. The status number, a measure of genetic diversity, was calculated as 26.4 (2002), 23.9 (2003), and 24.0 (2004). On average, the relative status number, estimated based on total fertility, was 86% of the census number. Sexual asymmetry calculations showed that clonal contributions would be balanced between genders. Some management activities such as adjusting ramet number to balance clone contributions and mixing of seeds from consecutive years are suggested for the black pine seed orchard.

Sign in / Sign up

Export Citation Format

Share Document