scholarly journals Optimal Clone Number for Seed Orchards with Tested Clones

2005 ◽  
Vol 54 (1-6) ◽  
pp. 80-92 ◽  
Author(s):  
D. Lindgren ◽  
F. Prescher
Keyword(s):  
Loblolly Pine ◽  
Genetic Variance ◽  
Gene Diversity ◽  
Selection Criterion ◽  
Seed Orchard ◽  
Optimal Number ◽  
Sensitivity Analyses ◽  
Seed Orchards ◽  
Status Number ◽  
The Impact

Abstract The optimal number of clones in seed orchards is discussed. A model is constructed to maximize a goodness criterion (“benefit”) for seed orchards. This criterion is a function of: 1) the number of tested genotypes available for selection and planted in seed orchard; 2) the contribution to pollination from: a) the ramet itself; b) the closest neighbors; c) the rest of the orchard and sources outside the orchard (contamination); 3) variation among genotypes for fertility; 4) frequency of selfing; 5) production of selfed genotypes; 6) gene diversity (= status number); 7) influence of contamination; 8) genetic variation among candidates; 9) correlation between selection criterion (e.g. height in progeny test) and value for forestry (e.g. production in forests from the orchard); and 10) the number of clones harvested. Numeric values of the entries are discussed, and values were chosen to be relevant for scenarios with Swedish conifers (focusing on Scots pine) and for loblolly pine. Benefit was maximized considering the number of clones. The optimum was 16 clones for the Swedish scenario, while less for the loblolly pine scenario. The optimum was rather broad, thus it is not essential to deploy the exact optimum, and an approximate optimum will do. A sensitivity analyses was performed to evaluate the importance of the likely uncertainty and variation in different entries. Quantification of the benefit of gene diversity is important. Other significant considerations are the genetic variance in the goal character and the ability to predict it, as well as the impact of selfing and the variation in reproductive success between clones. Twenty clones is suggested as a thumb rule for Swedish conifers.

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 Integrating fecundity variation and genetic relatedness in estimating the gene diversity of seed crops: Pinus koraiensis seed orchard as an example

2017 ◽  
Vol 47 (3) ◽  
pp. 366-370 ◽  
Author(s):  
Ji-Min Park ◽  
Soon-Ho Kwon ◽  
He-Jin Lee ◽  
Sung-Joon Na ◽  
Yousry A. El-Kassaby ◽  
...  
Keyword(s):  
Genetic Gain ◽  
Genetic Relatedness ◽  
Gene Diversity ◽  
Seed Orchard ◽  
Cumulative Distribution ◽  
Pinus Koraiensis ◽  
Total Production ◽  
Clonal Seed Orchard ◽  
Status Number ◽  
Seed Crops

The genetic gain and gene diversity of seed crops from a 1.5-generation clonal seed orchard of Pinus koraiensis Siebold & Zucc. were estimated under consideration of parental genetic values and fecundity variation. Fecundity variation among clones was estimated for 5 consecutive years (2010–2014) as the sibling coefficient, which was drawn from clonal contribution to the total production of seed conelet. To monitor gene diversity, status number was estimated by the integration of fecundity variation and group coancestry. Group coancestry was calculated as the average of genetic relatedness (coancestry) among orchard clones. The averages of conelet production were high in 2010 and 2011, moderate in 2013 and 2014, and poor in 2012 with a grand mean of 13.7. Correlation analysis showed that good conelet producers consistently gave good production. Cumulative distribution of clonal conelet production was presented as a function of the total conelet yield, and this distribution indicated deviation from the expected clonal equal production. Group coancesrtry was 0.0096, indicating minimal loss of gene diversity. Status number and genetic gain were higher in good than in poor conelet production years, highlighting the importance of fecundity variation in determining the genetic gain and gene diversity of seed orchard crops.

scholarly journals Strategies for Optimal Deployment of Related Clones into Seed Orchards

2008 ◽  
Vol 57 (1-6) ◽  
pp. 119-127 ◽  
Author(s):  
D. Danusevičius ◽  
D. Lindgren
Keyword(s):  
Gene Diversity ◽  
Seed Orchard ◽  
Breeding Values ◽  
Truncation Selection ◽  
Deployment Strategy ◽  
Ranking Criteria ◽  
The Status ◽  
Sib Families ◽  
Optimal Deployment ◽  
Status Number

Abstract This study deals with how the deployed proportion of each candidate clone can be decided at the establishment of a seed orchard when the breeding values are available for each candidate in a population of unrelated half-sib families. The following deployment strategies were compared: (a) truncation selection by selecting the clones with the breeding values exceeding certain threshold and deploying equal number of ramets (Truncation strategy); (b) truncation selection by selecting only one best individual within each family (Truncation unrelated); (c) maximizing gain at a given effective clone number (Linear deployment); (d) linear deployment by selecting one best individual within each family (Linear deployment unrelated) and (e) maximizing net gain at a given gene diversity (Optimal proportions). The study focused on the latest alternative and described its superiority and characteristics for a number of possible typical cases. The genetic gain adjusted for predicted inbreeding depression (Net gain), gene diversity and effective clone number were considered as the main ranking criteria. The strategies optimizing the number of related individuals and the linear deployment strategy with restriction on relatedness returned the highest Net gain. If there is a large diversity to select from (the status number of the candidates is more than 8 times greater than the status number desired in the seed orchard), a relatively simple advice is to select the best individual within the best families and deploy the clones linearly according to their breeding values (the number of families selected depends on the desired status number). If the diversity available to select from is small, it seems recommendable to allow half-sibs among the selections and use the Optimal proportions deployment strategy. As the breeding cycles proceed, the status number of the candidate population will decrease and the Optimal proportions strategy is likely to become more favorable.

Flower Stimulation Treatments in a Loblolly Pine Seed Orchard

1991 ◽  
Vol 15 (1) ◽  
pp. 44-50 ◽  
Author(s):  
N. C. Wheeler ◽  
D. L. Bramlett
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Female Flower ◽  
Seed Orchard ◽  
Single Treatment ◽  
Considerable Effort ◽  
Seed Orchards ◽  
Flower Production ◽  
Pinus Taeda L ◽  
A Site

Abstract Flowering in conifer seed orchards may be sporadic and insufficient to meet reforestation needs at early ages. Consequently, considerable effort has been made to develop cultural treatments to enhance flowering in operational seed orchards. For a number of species, flower-promoting technology is well-defined. This study evaluated two known technologies, currently in use for other species, for flower-promoting effects in loblolly pine (Pinus taeda L.). A replicated experiment was installed in a 10-year-old, second-generation loblolly pine seed orchard at Lyons, GA. Overlapping, saw-cut girdles and stem-injected GA4/7 were applied alone, and in combination, to main boles of ramets of four clones. Timing of treatments was evaluated using four treatment dates. All treatments significantly enhanced female flower production, relative to controls, although girdling was clearly the most effective single treatment. There was no treatment effect on pollen production. Timing of treatment is important but may require evaluation on a site-by-site basis. Tree health 1 year after treatment was excellent, although clonal sensitivity to some treatments was noted. Use of flower stimulation techniques is recommended, particularly for younger loblolly pine orchards. South J. Appl. For. 15(1):44-50.

scholarly journals Systemic Insecticide Injections for Control of Cone and Seed Insects in Loblolly Pine Seed Orchards—2 Year Results

2002 ◽  
Vol 26 (3) ◽  
pp. 146-152 ◽  
Author(s):  
Donald M. Grosman ◽  
William W. Upton ◽  
Frank A. McCook ◽  
Ronald F. Billings
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Seed Orchard ◽  
Systemic Insecticide ◽  
East Texas ◽  
Emamectin Benzoate ◽  
Seed Orchards ◽  
Pinus Taeda L ◽  
Cone And Seed Insects ◽  
Seed Insects

Abstract Three systemic insecticide treatments, emamectin benzoate alone, imidacloprid alone, and a combination of emamectin benzoate and thiamethoxam, were injected one or two times into loblolly pine,Pinus taeda L., during a 2 yr period in a seed orchard in east Texas. Single injections of treatments containing emamectin benzoate reduced coneworm (Dioryctria spp.) damage by 94–97% during the study period. A second injection after 1 yr did not improve protection. Imidacloprid also significantly reduced coneworm damage in 1999, but not in 2000. Significant reductions in damage from pine seed bugs (Tetyra bipunctata Say andLeptoglossus corculus Herrich-Schaffer) and an increase in the number of full seeds per cone resulted from imidacloprid and thiamethoxam treatments and to a lesser extent from emamectin benzoate. Yearly injections of imidacloprid or thiamethoxam were required to maintain protection against seed bugs. The best overall treatment, two injections of emamectin benzoate plus thiamethoxam, reduced cone and seed losses from insects by 86%. South. J. Appl. For. 26(3):146–152.

scholarly journals Influence of Forestry Practices Cost on Financial Performance of Forestry Investments

Resources ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 28 ◽  
Author(s):  
Daniel Callaghan ◽  
Puskar Khanal ◽  
Thomas Straka ◽  
Donald Hagan
Keyword(s):  
Loblolly Pine ◽  
Site Preparation ◽  
Optimal Number ◽  
Discounted Cash Flow ◽  
Management Scenarios ◽  
Plantation Management ◽  
Forestry Practices ◽  
The Face ◽  
Rotation Age ◽  
The Impact

Understanding forestry practices cost is important for predicting the financial outcome of forest management activities. Assessing costs of practices that will be used in the future can be difficult and may result in over or underestimations of financial returns depending on the values used. We used historic real average rates of cost change for the southern United States to assess changes in the values of several loblolly pine plantation management scenarios over time through the use of discounted cash flow (DCF) analysis. Additionally, we analyzed the impact of certain practices cost changes on the financially optimal number of thinnings and rotation age. Findings indicated that declining costs for herbicide site preparation could all but offset the increasing costs of other practices and that a relatively slight increase in timber prices would more than compensate for increasing costs. Also, increasing thinning costs could exacerbate the effects of low sawtimber prices, further decreasing the viability of regimes with multiple thinnings. In the face of stagnant timber prices, the use of operator-select thinnings, and herbicide site preparation could stabilize the long-term financial value of plantation management.

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 Fertility Variation, Genetic Relatedness, and Their Impacts on Gene Diversity of Seeds From a Seed Orchard of Pinus thunbergii

2004 ◽  
Vol 53 (1-6) ◽  
pp. 202-206 ◽  
Author(s):  
K. S. Kang ◽  
D. Lindgren ◽  
T. J. Mullin
Keyword(s):  
Genetic Relatedness ◽  
Gene Diversity ◽  
Seed Orchard ◽  
Pinus Thunbergii ◽  
Clonal Seed Orchard ◽  
Fertility Variation ◽  
The Status ◽  
Status Number ◽  
Census Number ◽  
Natural Stands

AbstractClonal differences in the number of male and female strobili were determined for five consecutive years in a clonal seed orchard of Pinus thunbergii in Korea. The effects of relatedness and clonal differences in reproductive development on gene diversity of seed (in terms of accumulated relatedness by status number) were estimated. While clonal differences were found, fertility variation was not large through all studied years. The orchard clones were divided into different regions and locations based on the geographical distribution and distance of natural stands that plus trees were selected from. Assuming that there was no relatedness among regions, locations and clones, the status number (Ns) was varied from 47.6 to 55.5 for five successive years. On average (pooling), Nswas 92% of census number (N). Assumed relatedness among regions, locations and/or clones decreased the status number. Effect of parental selection on relatedness and orchard management was also discussed.

scholarly journals Efficiencies of Clonally Replicated and Seedling Testing for Spruce Breeding and Deployment Strategies

2009 ◽  
Vol 58 (1-6) ◽  
pp. 292-300
Author(s):  
Y. H. Weng ◽  
Y. S. Park ◽  
D. Simpson ◽  
T. J. Mullin
Keyword(s):  
Genetic Variance ◽  
Gene Diversity ◽  
Additive Genetic Variance ◽  
Seed Orchard ◽  
Narrow Sense ◽  
Family Selection ◽  
Narrow Sense Heritability ◽  
Additive Variance ◽  
Clonal Seed Orchard ◽  
Seedling Test

AbstractGenetic gains based on a genetic test using clonal replicates were compared to those based on a test using seedlings at the same gene diversity and testing effort levels using POPSIM™ Simulator. Three testing and deployment strategies targeting for white spruce (P. glauca [Moench] Voss) and black spruce (P. mariana (Mill.) B.S.P.) in New Brunswick were compared: seedling test with clonal seed orchard deployed as seedlings (CSO_ST), clonally replicated test with clonal seed orchard deployed as seedlings (CSO_CRT), and clonally replicated test deployed as a clone mix (MVF). The breeding populations (BP) were formed by balanced within-family selection and the production populations (PP) were selected by strong restriction on relatedness, i.e., no parent in common. Compared to the seedling test, the clonally replicated test resulted in faster accumulation of additive effects but quicker loss of additive variance in the BP, and this is particular true in the case of lower narrow-sense heritability or less non-additive genetic variance. The quicker loss in BP additive variance was overcompensated for by its faster accumulation in BP additive effect, resulting in higher gain in the clonally replicated test based PPs. Compared to the CSO_ST, the gain superiority of the CSO_CRT increased with generations, decreasing narrow-sense heritability or reducing the amount of non-additive variance. Implementing MVF was the most effective in terms of gain in most simulated cases and its superiority over the CSO_ST increased with generations, decreasing narrowsense heritability, or increasing non-additive genetic variance. Overall results demonstrated significant advantages of using clonally replicated test both for BP advancement and PP selection in most of the scenarios, suggesting that clonally replicated test should be incorporated into current spruce breeding strategies.

A Southwide Test of Bifenthrin (Capture®) for Cone and Seed Insect Control in Seed Orchards

1994 ◽  
Vol 18 (2) ◽  
pp. 72-75
Author(s):  
W. J. Lowe ◽  
L. R. Barber ◽  
R. S. Cameron ◽  
G. L. DeBarr ◽  
G. R. Hodge ◽  
...  
Keyword(s):  
South Carolina ◽  
Loblolly Pine ◽  
Seed Orchard ◽  
Slash Pine ◽  
Insect Control ◽  
Seed Orchards ◽  
Southern States ◽  
Pinus Taeda L ◽  
Cone And Seed Insects ◽  
Aerial Sprays

Abstract In 1991, a Southwide study to evaluate the efficacy of bifenthrin (Capture®) for cone and seed insect control was established in six loblolly pine (Pinus taeda L.) and three slash pine (P. elliottii Engelm.) seed orchards. A control (no treatment), Capture® (bifenthrin), and Guthion® (azinphosmethyl) treatments were established in each seed orchard. Five aerial sprays were used to apply the insecticides during the growing season. At each spray Guthion® was applied at 3 lb ai/ac. Capture® was applied at 0.2 lb ai/ac for the first spray and 0.1 lb ai/ac for the other four sprays. Under the conditions of this study, Capture® was as effective in controlling cone and seed insects as the standard operational Guthion® treatment. Insecticide treatment resulted in a 42% and 17% increase in the number of sound seeds produced per conelet for loblolly and slash pine, respectively. Local need registration (24C) exists in several states, and seed orchard managers can currently use Capture® in Alabama, Arkansas, Georgia, Louisiana, Mississippi, Oklahoma, South Carolina and Tennessee. Seed orchard managers in other southern states need to determine if a 24C label is available in their state prior to useage. South. J. Appl. For. 18(1):72-75.

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