scholarly journals Sexual Asymmetry based on Flowering Assessment in a Clonal Seed Orchard of Pinus densiflora

2004 ◽  
Vol 53 (1-6) ◽  
pp. 55-59 ◽  
Author(s):  
W.Y. Choi ◽  
K. S. Kang ◽  
K.W. Jang ◽  
S. U. Han ◽  
C. S. Kim
Keyword(s):  
Relative Frequency ◽  
Pinus Densiflora ◽  
Seed Orchard ◽  
Arithmetic Mean ◽  
Effective Number ◽  
Effective Population ◽  
Yearly Variation ◽  
Clonal Seed Orchard ◽  
Male Strobilus ◽  
Population Numbers

AbstractTwo equations were formulated in order to estimate the degree of sexual asymmetry for monoecious species. The concepts of the equations were formulated on the basis of the effective population numbers of female and male parents [i.e, As(v)], and the differences of relative frequency between genders [i.e., As(x)]. These equations were applied to estimate the degree of sexual asymmetry based on the empirical data of flowering assessment in a clonal seed orchard of Pinus densiflora. The yearly variation in the production of female and male strobili was found. The effective population numbers at gamete levels (vfand vm) and clone level (vb) varied among 8 observation years. Both As(x)and As(v)were negatively correlated with effective numbers at gamete and clone levels. Averages of female and male strobilus production and estimates of sexual asymmetry were negatively correlated but the correlation was not significant. The correlations among effective number of clone (vb), arithmetic mean of female and male effective numbers (va) and estimate of sexual asymmetry [As(x)] were strong and significant. Relatively larger difference between vb and va were found when higher level of sexual asymmetry were observed.

Mating system estimates and effective population numbers for an isolated noble fir (Abiesprocera) clonal seed orchard in Denmark

1996 ◽  
Vol 26 (7) ◽  
pp. 1135-1141 ◽  
Author(s):  
Hans R. Siegismund ◽  
Erik D. Kjær ◽  
Ulrik Bräuner Nielsen
Keyword(s):  
Mating System ◽  
Seed Orchard ◽  
Allele Frequencies ◽  
Homogeneous Distribution ◽  
Effective Population ◽  
Population Number ◽  
Clonal Seed Orchard ◽  
Isozyme Loci ◽  
Noble Fir ◽  
Population Numbers

The mating system of a seed orchard of noble fir (Abiesprocera Rehd.) in Denmark was analyzed, with variation being found at two unlinked isozyme loci. Comparison of allele frequencies in the pollen pool fertilizing the upper and the lower parts of the trees showed a homogeneous distribution. There was no difference in the outcrossing rates estimated for cones harvested at the top and the lowermost branches carrying cones. Both were slightly greater than 1, as was the combined estimate that did not differ significantly from 1. The clones present in the seed orchard are outcrossing, and the allele frequencies found in the pollen pool agree with the frequencies found in the clones of the seed orchard on average. However, the allele frequencies varied significantly between the 20 families, suggesting that the pollen pool has been variable within the seed orchard. The inbreeding and variance effective population numbers were estimated by assuming that the differences in flowering reflected variation in gamete contribution from the clones to the offspring. The inbreeding effective population number was found to be 65% of the total number of clones. The variance effective population number was 121% of the number of clones when it was assumed that a large number of offspring were harvested from every clone.

Paternity analysis with microsatellites in a Danish Abies nordmanniana clonal seed orchard reveals dysfunctions

2006 ◽  
Vol 36 (4) ◽  
pp. 1054-1058 ◽  
Author(s):  
O K Hansen ◽  
E D Kjær
Keyword(s):  
Asymptotic Variance ◽  
Seed Orchard ◽  
Paternity Analysis ◽  
Effective Population ◽  
Population Number ◽  
Clonal Seed Orchard ◽  
Relative Contribution ◽  
Male Gametes ◽  
Abies Nordmanniana ◽  
The Status

A paternity analysis using five microsatellite markers was conducted in a Danish clonal seed orchard with 13 Abies nordmanniana (Stev.) Spach clones. The purpose was to investigate potential seed-orchard dysfunctions, with special emphasis on nonequal pollen contributions and selfing. Male paternity was found for 232 seedlings germinated from seeds collected on three ramets, each of eight clones, and the relative contribution of each clone to the gene pool of male gametes was calculated. Furthermore, 49 ramets were genotyped to check for erroneous grafting. The effect of an unbalanced male contribution was quantified by means of two measures: (1) the status number (NS), which reflects buildup of coancestry in the seed-orchard crop as a result of a low number of clones and an unequal male contribution, and (2) the asymptotic variance effective population number (Ne(v)). The contributions by pollen donors from the 13 clones were highly skewed. Three clones were fathers to more than 75% of the progenies, while making up only 24% of the ramets in the seed orchard. Four clones sired no progenies at all. The unequal contribution on the male side corresponded to NS = 4.2 and Ne(v) = 5.8. Some selfing was observed, which may give rise to concern if clonal seed orchards with few clones are established. The estimated maximum pollen contamination from outside the seed orchard was 4.3%. No grafting–labelling errors were identified.

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 Gender, reproductive output covariation and their role on gene diversity of Pinus koraiensis seed orchard crops

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Ji-Min Park ◽  
Hye-In Kang ◽  
Da-Bin Yeom ◽  
Kyu-Suk Kang ◽  
Yousry A. El-Kassaby ◽  
...  
Keyword(s):  
Gene Diversity ◽  
Fundamental Equation ◽  
Seed Orchard ◽  
Pinus Koraiensis ◽  
Effective Number ◽  
Effective Population ◽  
Management Options ◽  
Fertility Variation ◽  
Census Number ◽  
Seed Crops

Abstract Background Gender and fertility variation have an impact on mating dynamics in a population because they affect the gene exchange among parental members and the genetic composition of the resultant seed crops. Fertility is the proportional gametic contribution of parents to their progeny. An effective number of parents, derivative of effective population size, is the probability that two alleles randomly chosen from the gamete gene pool originated from the same parent. The effective number of parents is directly related to the fertility variation among parents, which should be monitored for manipulating gene diversity of seed crops. We formulated a fundamental equation of estimating the effective number of parents and applied it to a seed production population. Results Effective number of parents (Np) was derived from fertility variation (Ψ) considering covariance (correlation coefficient, r) between maternal and paternal fertility. The Ψ was calculated from the coefficient of variation in reproductive outputs and divided into female (ψf) and male (ψm) fertility variation in the population under study. The Np was estimated from the parental Ψ estimated by the fertility variation of maternal (ψf) and paternal (ψm) parents. The gene diversity of seed crops was monitored by Ψ and Np. in a 1.5 generation Pinus koraiensis seed orchard as a case of monoecious species. A large variation of female and male strobili production was observed among the studied 52 parents over four consecutive years, showing statistically significant differences across all studied years. Parental balance curve showed greater distortion in paternal than maternal parents. The Ψ ranged from 1.879 to 4.035 with greater ψm than ψf, and the Np varied from 14.8 to 36.8. When pooled, the relative effective number of parents was improved as 80.0% of the census number. Conclusions We recommend the use of fertility variation (i.e., CV, Ψ), Person’s product-moment correlation (r), and effective number of parents (Np) as tools for gauging gene diversity of seed crops in production populations. For increasing Np and gene diversity, additional management options such as mixing seed-lots, equal cone harvest and application of supplemental-mass-pollination are recommended.

Development of flowering and the effect of pruning in a clonal seed orchard of lodgepole pine

1994 ◽  
Vol 24 (1) ◽  
pp. 71-76 ◽  
Author(s):  
Anders Fries
Keyword(s):  
Population Size ◽  
Effective Population Size ◽  
Lodgepole Pine ◽  
Seed Orchard ◽  
Effective Population ◽  
Clonal Seed Orchard ◽  
Crown Volume ◽  
Female Flowering ◽  
Male Strobili

The development of female and male flowering among 20 clones was studied in a clonal seed orchard of lodgepole pine (Pinuscontorta var. latifolia Engelm.) in central Sweden. Flowering in relation to height, crown volume, and pruning was also studied. Twelve years after grafting (7 years after field planting), female flowering averaged 43 strobili per graft while male strobili were few. Eighteen years from grafting, the number of female and male strobuli were 143 and 142, respectively. The female effective population size was around 80% of maximum and was stable during the whole period. The male effective population size increased from 25 to 68%. Index of monoecy increased from 58 to 81% of maximum. The results indicate that at around 18 years after grafting, female and male flowering were satisfactorily distributed among the clones. There were no clonal correlations between male flowering and female flowering, while correlations between years for those traits separately were strong. Male flowering showed stronger correlation to the size of the graft than female flowering.

scholarly journals Gender, reproductive output covariation and their role on gene diversity of Pinus koraiensis seed orchard crops

2020 ◽  
Author(s):  
Kyu-Suk Kang ◽  
Ji-Min Park ◽  
Hye-In Kang ◽  
Da-Bin Yeom ◽  
Yousry A. El-Kassaby ◽  
...  
Keyword(s):  
Gene Diversity ◽  
Fundamental Equation ◽  
Seed Orchard ◽  
Pinus Koraiensis ◽  
Effective Number ◽  
Effective Population ◽  
Management Options ◽  
Fertility Variation ◽  
Census Number ◽  
Seed Crops

Abstract Background: Gender and fertility variation have an impact on mating dynamics in a population because they affect the gene exchange among parental members and the genetic composition of the resultant seed crops. Fertility is the proportional gametic contribution of parents to their progeny. An effective number of parents, derivative of effective population size, is the probability that two alleles randomly chosen from the gamete gene pool originated from the same parent. The effective number of parents is directly related to the fertility variation among parents, which should be monitored for manipulating gene diversity of seed crops. We formulated a fundamental equation of estimating the effective number of parents and applied it to a seed production population.Results: Effective number of parents (Np) was derived from fertility variation (Y) considering covariance (correlation coefficient, r) between maternal and paternal fertility. The Y was calculated from the coefficient of variation in reproductive outputs and divided into female (yf) and male (ym) fertility variation in the population under study. The Np was estimated from the parental Y estimated by the fertility variation of maternal (yf) and paternal (ym) parents. The gene diversity of seed crops was monitored by Y and Np. in a 1.5 generation Pinus koraiensis seed orchard as a case of monoecious species. A large variation of female and male strobili production was observed among the studied 52 parents for four consecutive years, showing statistically significant across all studied years. Parental balance curve showed greater distortion in paternal parents than maternal parents. The Y ranged from 1.879 to 4.035 with greater ym than yf, and the Np varied from 14.8 to 36.8. When pooled, the relative effective number of parents was improved as 80.0% of the census number. Conclusions: We recommend the use of fertility variation (i.e., CV, Y), Person’s product-moment correlation (r) and effective number of parents (Np) as tools for gauging gene diversity of seed crops in production populations. For increasing Np and gene diversity, additional management options such as mixing seed-lots, equal cone harvest and application of supplemental-mass-pollination are recommended.

Clonal and annual variation of flower production and composition of gamete gene pool in a clonal seed orchard of Pinus densiflora

2000 ◽  
Vol 30 (8) ◽  
pp. 1275-1280 ◽  
Author(s):  
Kyu-Suk Kang
Keyword(s):  
Pinus Densiflora ◽  
Rank Correlation ◽  
Correlation Coefficients ◽  
Seed Orchard ◽  
Flower Production ◽  
Clonal Seed Orchard ◽  
Spearman’S Rank Correlation ◽  
Total Female ◽  
Male Flowers ◽  
Male Strobili

The numbers of female and male strobili were assessed for 99 clones in a Pinus densiflora Sieb. et Zucc. seed orchard for four consecutive years. The data showed that differences for the production of both female and male strobili among clones were very large and statistically significant for all years examined. The most abundant quartile of clones produced 48.1 and 37.3% of the total female and male strobili, respectively, averaged over the 4-year period. Differences in female strobilus production among clones were more variable than in male. Pearson's correlations between years for flower production were positive for all combinations of years. Spearman's rank correlation coefficients between years with moderate female flowers were highly significant. Both correlations between female and male flowers were moderate and positive for all 4 years. Broad-sense heritabilities for flower production on an individual ramet basis varied from 0.19 to 0.41, while those on a clone-mean basis were much higher, from 0.57 to 0.80. Maleness index showed that sexual symmetry in good and poor flower years deviated more from the ideal panmictic situation than that in intermediate years. Parental balance curves showed that orchard clones contributed more equally to the seed crop when flower production was moderate.

scholarly journals Variation in Clone Fertility and its Effect on the Gene Diversity of Seeds From a Seed Orchard of Chamaecyparis obtusa in Korea

2007 ◽  
Vol 56 (1-6) ◽  
pp. 134-137 ◽  
Author(s):  
K. S. Kang ◽  
T. J. Mullin
Keyword(s):  
Gene Diversity ◽  
Seed Orchard ◽  
Chamaecyparis Obtusa ◽  
Clonal Seed Orchard ◽  
Fertility Variation ◽  
The Status ◽  
Status Number ◽  
Census Number ◽  
One Year ◽  
Male Strobilus

Abstract Male and female strobilus production was assessed annually over a four-year period for a clonal seed orchard of hinoki (Chamaecyparis obtusa Endl.) in Korea. Clonal fertility and fertility variation, expressed by both sibling coefficient and coefficient of variation in strobilus production among 50 orchard clones, were reported. Fertility varied among clones and among years producing four-year averages per ramet of 510.2 and 1050.6 for female and male strobili, respectively. The correlation between female and male strobilus production was positive in each of the four years studied and, with the exception of one year, statistically significant. The clonal status number (Ns), a measure of gene diversity, was calculated based on the observed clonal fertility variation and varied from 28.0 (N = 50) in the poorest flowering year (2002) to 46.7 in the best year (2005). On average (pooled), the relative status number was 95% of the census number (N). Variation in female fertility was generally higher than that for male fertility, and this variation was reflected in the status numbers of female and male parents. The pooled Ns estimated from all four years was higher than that for any single year, implying that gene diversity would increase when seeds collected from different years are pooled. Sexual asymmetry calculations showed that clonal contributions would be balanced between genders.

Relatedness and status number in seed orchard crops

1998 ◽  
Vol 28 (2) ◽  
pp. 276-283 ◽  
Author(s):  
D Lindgren ◽  
T J Mullin
Keyword(s):  
Gender Differences ◽  
Reproductive Success ◽  
Population Size ◽  
Effective Population Size ◽  
Seed Orchard ◽  
Reference Population ◽  
Sexual Cycle ◽  
Effective Number ◽  
Effective Population ◽  
Status Number

Status number is a measure of effective population size that is based on current relatedness only. Formulae are developed for group coancestry (=average coancestry) and status number for seed orchard crops. The formulae consider (1) differences in reproductive success among orchard genotypes, (2) relatedness between pairs of orchard genotypes, (3) inbreeding of orchard genotypes, (4) influence of pollen contamination (considering its relatedness both to itself and to the genotypes in the orchard), and (5) gender differences and sexual asymmetries of orchard genotypes. Properties of status number and other measures of effective number are discussed. They may refer to rate or state, to the reference population or the development of an idealized population, and to different moments in the sexual cycle.

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